Exclude CODEOWNERS from language statistics

update: bump PacketEvents to version 2.11.2

.gitattributes

@@ -0,0 +1 @@
+.gitea/CODEOWNERS linguist-detectable=false

.gitea/CODEOWNERS

@@ -0,0 +1,3 @@
+# Pull requests request review from the eligible staff team(s).
+# One approval from either an Admin or Developer satisfies branch protection.
+*   @trueog/Admins @trueog/Developers

.github/workflows/build-gradle.yml

@@ -0,0 +1,208 @@
+name: Build and Version Update
+
+permissions:
+  contents: write
+
+on:
+  push:
+    branches:
+      - main
+      - merge
+      - dev
+      - fabric-experimental-gradle
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout main repository
+        uses: actions/checkout@v2
+
+      # 2. Install JDK 21 – NO Gradle cache here
+      - name: Set up JDK
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: 21
+          cache: ''                          # ← disable Maven/Gradle cache
+
+      # 3. Set up Gradle + dependency cache
+      - name: Set up Gradle
+        uses: gradle/actions/setup-gradle@v5
+
+      - name: Generate build number
+        id: buildnumber
+        uses: einaregilsson/build-number@v3
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Update version in build.gradle.kts
+        id: update_version
+        run: |
+          # Read current fullVersion from build.gradle.kts
+          FULL_VERSION=$(grep 'val fullVersion =' build.gradle.kts | awk -F '"' '{print $2}')
+          IFS='.' read -ra VERSION_PARTS <<< "$FULL_VERSION"
+          PATCH=$((VERSION_PARTS[2] + 1))
+          NEW_VERSION="${VERSION_PARTS[0]}.${VERSION_PARTS[1]}.$PATCH-dev-b${{ steps.buildnumber.outputs.build_number }}"
+          echo "NEW_VERSION=${NEW_VERSION}" >> $GITHUB_ENV
+          
+          # Update fullVersion in build.gradle
+          sed -i "s/val fullVersion = \".*\"/val fullVersion = \"$NEW_VERSION\"/" build.gradle.kts
+          
+          # Ensure snapshot is set to false
+          sed -i "s/val snapshot = .*/val snapshot = false/" build.gradle.kts
+
+      - name: Build without PE shaded
+        run: ./gradlew build -PshadePE=false -x test
+        env:
+          GITHUB_REPOSITORY: ${{ github.repository }}
+
+      - name: Build with PE shaded Gradle
+        run: ./gradlew build -PshadePE=true -x test
+        env:
+          GITHUB_REPOSITORY: ${{ github.repository }}
+
+      # Get the Hashes of the Original and Lite JARs
+      - name: Calculate Hashes
+        run: |
+          # Calculate hash for the original JAR
+          BUKKIT_HASH=$(sha256sum bukkit/build/libs/knockbacksync-bukkit-${{ env.NEW_VERSION }}.jar | awk '{print $1}')
+          echo "BUKKIT_HASH=$BUKKIT_HASH" >> $GITHUB_ENV
+          # Calculate hash for the lite JAR
+          BUKKIT_LITE_HASH=$(sha256sum bukkit/build/libs/knockbacksync-bukkit-lite-${{ env.NEW_VERSION }}.jar | awk '{print $1}')
+          echo "BUKKIT_LITE_HASH=$BUKKIT_LITE_HASH" >> $GITHUB_ENV
+          # Calculate hash for the lite JAR
+          FABRIC_HASH=$(sha256sum fabric/build/libs/knockbacksync-fabric-${{ env.NEW_VERSION }}.jar | awk '{print $1}')
+          echo "FABRIC_HASH=$FABRIC_HASH" >> $GITHUB_ENV
+
+      # Download, update, and re-upload dev-builds.txt
+      - name: Update dev-builds.txt
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        run: |
+          # Download the current dev-builds.txt
+          curl -L -o dev-builds.txt https://github.com/${{ github.repository }}/releases/latest/download/dev-builds.txt
+          
+          # Create a copy of the original file
+          cp dev-builds.txt dev-builds.txt.original
+          
+          # Ensure the file ends with a newline
+          sed -i -e '$a\' dev-builds.txt
+          
+          # Function to add hash if it doesn't exist
+          add_hash_if_new() {
+            if ! grep -q "$1" dev-builds.txt; then
+              echo "$1" >> dev-builds.txt
+            fi
+          }
+          
+          # Add new hashes if they don't exist
+          add_hash_if_new "${{ env.BUKKIT_HASH }}"
+          add_hash_if_new "${{ env.BUKKIT_LITE_HASH }}"
+          add_hash_if_new "${{ env.FABRIC_HASH }}"
+          
+          # Check if the file has changed
+          if cmp -s dev-builds.txt dev-builds.txt.original; then
+            echo "No changes to dev-builds.txt, skipping upload."
+          else
+            echo "Changes detected in dev-builds.txt, uploading new version."
+          
+            # Get the latest release ID
+            RELEASE_ID=$(curl -s "https://api.github.com/repos/${{ github.repository }}/releases/latest" | jq -r .id)
+          
+            # Delete the old dev-builds.txt asset
+            ASSET_ID=$(curl -s -H "Authorization: token $GITHUB_TOKEN" \
+              "https://api.github.com/repos/${{ github.repository }}/releases/$RELEASE_ID/assets" | \
+              jq -r '.[] | select(.name == "dev-builds.txt") | .id')
+            if [ ! -z "$ASSET_ID" ]; then
+              curl -X DELETE -H "Authorization: token $GITHUB_TOKEN" \
+                "https://api.github.com/repos/${{ github.repository }}/releases/assets/$ASSET_ID"
+            fi
+          
+            # Upload the new dev-builds.txt
+            curl -X POST -H "Authorization: token $GITHUB_TOKEN" \
+              -H "Content-Type: application/octet-stream" \
+              --data-binary @dev-builds.txt \
+              "https://uploads.github.com/repos/${{ github.repository }}/releases/$RELEASE_ID/assets?name=dev-builds.txt"
+          fi
+          
+          # Clean up
+          rm dev-builds.txt.original
+
+      - name: Upload Bukkit Artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: knockbacksync-bukkit-${{ env.NEW_VERSION }}.jar
+          path: bukkit/build/libs/knockbacksync-bukkit-${{ env.NEW_VERSION }}.jar
+          retention-days: 90
+
+      - name: Upload Bukkit Lite Artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: knockbacksync-bukkit-lite-${{ env.NEW_VERSION }}.jar
+          path: bukkit/build/libs/knockbacksync-bukkit-lite-${{ env.NEW_VERSION }}.jar
+          retention-days: 90
+
+      - name: Upload Fabric Artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: knockbacksync-fabric-${{ env.NEW_VERSION }}.jar
+          path: fabric/build/libs/knockbacksync-fabric-${{ env.NEW_VERSION }}.jar
+          retention-days: 90
+
+      - uses: Kir-Antipov/mc-publish@v3.3
+        with:
+          modrinth-id: ${{ vars.MODRINTH_ID  }}
+          modrinth-featured: true
+          modrinth-unfeature-mode: subset
+          modrinth-token: ${{ secrets.MODRINTH_TOKEN }}
+
+          files: |
+            bukkit/build/libs/knockbacksync-bukkit-${{ env.NEW_VERSION }}.jar
+            bukkit/build/libs/knockbacksync-bukkit-lite-${{ env.NEW_VERSION }}.jar
+
+          name: KnockbackSync-${{ env.NEW_VERSION }}
+          version: ${{ env.NEW_VERSION }}
+          version-type: alpha
+
+          loaders: |
+            bukkit
+            spigot
+            paper
+            folia
+            purpur
+
+          game-versions: |
+            >=1.12.2
+
+          retry-attempts: 2
+          retry-delay: 10000
+          fail-mode: fail
+
+      - uses: Kir-Antipov/mc-publish@v3.3
+        with:
+          modrinth-id: ${{ vars.MODRINTH_ID }}
+          modrinth-featured: true
+          modrinth-unfeature-mode: subset
+          modrinth-token: ${{ secrets.MODRINTH_TOKEN }}
+
+          files: |
+            fabric/build/libs/knockbacksync-fabric-${{ env.NEW_VERSION }}.jar
+
+          name: KnockbackSync-${{ env.NEW_VERSION }}
+          version: ${{ env.NEW_VERSION }}
+          version-type: alpha
+
+          loaders: |
+            fabric
+
+          game-versions: |
+            1.21.11
+
+          dependencies: |
+            fabric-api
+
+          retry-attempts: 2
+          retry-delay: 10000
+          fail-mode: fail

.gitignore

@@ -6,3 +6,13 @@ dependency-reduced-pom.xml
 
 # Ignore maven build files
 target/
+
+# Eclipse files
+.classpath
+.project
+.settings/
+
+.gradle/
+build/
+
+run/

COPYING

@@ -1,674 +0,0 @@
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-    (at your option) any later version.
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-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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-
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-parts of the General Public License.  Of course, your program's commands
-might be different; for a GUI interface, you would use an "about box".
-
-  You should also get your employer (if you work as a programmer) or school,
-if any, to sign a "copyright disclaimer" for the program, if necessary.
-For more information on this, and how to apply and follow the GNU GPL, see
-<https://www.gnu.org/licenses/>.
-
-  The GNU General Public License does not permit incorporating your program
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-may consider it more useful to permit linking proprietary applications with
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-Public License instead of this License.  But first, please read
-<https://www.gnu.org/licenses/why-not-lgpl.html>.

DEVELOPER-NOTES.md

@@ -0,0 +1,35 @@
+## Project Structure
+
+- `common` submodule contains shared code for all platforms.
+  - It contains the interfaces and abstractions for
+    - Permissions
+    - Scheduling
+    - Players
+    - Blocks
+    - Worlds/Levels
+    - The Server
+  - In addition to the interfaces, the code also contains the implementations for
+    - Commands
+      - Commands use incendio's `cloud` command system. All you have to do to add platform support is to create a CommandManager and call register(). 
+    - Handling Events
+    - Gathering Statistics
+- `fabric` contains code for latest fabric version (currently 1.21)
+- `bukkit` contains bukkit-specific code
+
+If you want to add support for a new platform, simply make a new submodule and implement the interfaces for.
+- Scheduling Tasks
+- Checking for Permissions
+- Listening for events and calling the right handler
+- Players + Blocks + World + Server
+- Metrics
+
+You will need to handle events when Players:
+- join/leave
+- are damaged
+- take velocity (knock back)
+
+If you find your platform is lacking events, take a look at how the PlayerVelocityEvent is implemented fabric for some direction of what to do
+
+
+## List of version and platform-specific caveats
+- Runnable and manual ping does not work on fabric right now due b/c packetevents. Ping measurement will be less accurate

KnockbackSync.iml

@@ -5,6 +5,7 @@
       <configuration>
         <autoDetectTypes>
           <platformType>SPIGOT</platformType>
+          <platformType>ADVENTURE</platformType>
         </autoDetectTypes>
         <projectReimportVersion>1</projectReimportVersion>
       </configuration>

NOTICE

@@ -0,0 +1,37 @@
+KnockbackSync
+=============
+
+KnockbackSync is licensed under the GNU General Public License v3.0 or later.
+See README.md (section "License") and https://www.gnu.org/licenses/gpl-3.0.en.html.
+
+Bundled / ported third-party code
+----------------------------------
+
+This distribution contains a port of the 1.8 melee knockback formula from:
+
+    BukkitOldCombatMechanics (OldCombatMechanics)
+    Copyright (c) the OldCombatMechanics contributors (kernitus et al.)
+    https://github.com/kernitus/BukkitOldCombatMechanics
+    Licensed under the Mozilla Public License, Version 2.0 (MPL-2.0)
+    https://mozilla.org/MPL/2.0/
+
+The ported code lives in:
+
+    common/src/main/java/me/caseload/knockbacksync/util/LegacyKnockback.java
+
+It is derived from OldCombatMechanics' module
+`kernitus.plugin.OldCombatMechanics.module.ModulePlayerKnockback`.
+
+License compatibility
+---------------------
+
+The OldCombatMechanics source files are distributed under the standard MPL-2.0
+notice (Exhibit A) and do NOT carry the "Incompatible With Secondary Licenses"
+notice (Exhibit B). Under MPL-2.0 section 3.3, such Covered Software may be
+distributed as part of a Larger Work governed by a "Secondary License" — which
+MPL-2.0 section 1.12 defines to include the GNU General Public License, Version
+3. Accordingly, the ported file may be combined with and distributed alongside
+the GPL-3.0-or-later code that makes up the rest of KnockbackSync.
+
+The terms of the MPL-2.0 continue to govern the ported file itself; its MPL
+header is retained. The combined/Larger Work is offered under GPL-3.0-or-later.

README.md

@@ -1,29 +1,15 @@
-Minecraft doesn’t factor in network latency when determining a player's actions on the server.
-This causes the server to receive outdated information that doesn’t reflect the player's clientside position.
-As a result, players take negative velocity when they're on the ground clientside, but not serverside.
+# KnockbackSync-OG
 
-This plugin handles knockback as if it were calculated clientside, ensuring that no player is at a disadvantage,
-regardless of their own or their opponent’s connection.
-
-Showcase: https://www.youtube.com/watch?v=SVokpr3v-TA
-
-Official Discord: https://discord.gg/nnpqpAtyVW
-
-## Frequently Asked Questions (FAQ)
-
-### Does this change put high ping players at a disadvantage?
-**It depends on the player.** Some may notice a difference if they're used to relying on high ping to reduce knockback. For others, it could actually be an advantage.
-
-### How does this change benefit high ping players?
-**Knockback control.** For example, it will be easier to escape crit chains and punish crit.
-
-### Why was the configurability of ping offset removed?
-**It promotes consistency across all servers.** Extensive testing with top players has shown that an offset of 25 provides a balanced experience for everyone.
-
-### How do I change the ping offset?
-**You must run a modified build of KnockbackSync.** The variable can be changed inside of the [PlayerData](src/main/java/me/caseload/knockbacksync/manager/PlayerData.java) class.
+Soft fork of KnockbackSync to ensure compatibility with OldCombatMechanics on Purpur 1.19.4.
 
 ## License
 GNU General Public License v3.0 or later
 
-See [COPYING](COPYING) to see the full text.
+See [LICENSE](https://www.gnu.org/licenses/gpl-3.0.en.html) to see the full text.
+
+The optional legacy (1.8) knockback formula
+(`common/src/main/java/me/caseload/knockbacksync/util/LegacyKnockback.java`) is a
+port from [OldCombatMechanics](https://github.com/kernitus/BukkitOldCombatMechanics),
+which is licensed under the Mozilla Public License 2.0 (MPL-2.0). MPL-2.0 permits
+combining that code into this GPL-3.0-or-later work as a Larger Work (MPL-2.0
+§3.3 / §1.12). See the [NOTICE](NOTICE) file for details.

build.gradle.kts

@@ -0,0 +1,105 @@
+import java.io.ByteArrayOutputStream
+import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
+
+plugins {
+    id("java")
+    eclipse
+    id("com.gradleup.shadow") version "9.2.2" apply false
+}
+
+fun getGitCommitHash(project: Project): String? {
+    // Only try to get the hash if the .git directory exists
+    if (!project.file(".git").isDirectory) {
+        return null
+    }
+    return try {
+        val process = ProcessBuilder("git", "rev-parse", "--short", "HEAD")
+            .redirectOutput(ProcessBuilder.Redirect.PIPE)
+            .redirectError(ProcessBuilder.Redirect.PIPE)
+            .start()
+
+        process.waitFor(5, TimeUnit.SECONDS)
+
+        if (process.exitValue() == 0) {
+            process.inputStream.bufferedReader().readText().trim().takeIf { it.isNotEmpty() }
+        } else {
+            null
+        }
+    } catch (e: Exception) {
+        null
+    }
+}
+
+val fullVersion = "1.3.5"
+val snapshot = true
+val githubRepo = System.getenv("GITHUB_REPOSITORY") ?: project.findProperty("githubRepo").toString()
+
+// Suite default external provider; shaded standalone via -PshadePE=true.
+extra["shadePE"] = project.findProperty("shadePE")?.toString()?.toBoolean()
+    ?: System.getenv("SHADE_PE")?.toBoolean()
+    ?: false
+
+extra["relocate"] = project.findProperty("relocate")?.toString()?.toBoolean()
+    ?: System.getenv("RELOCATE_JAR")?.toBoolean()
+    ?: true
+
+allprojects {
+    fun getVersionMeta(includeHash: Boolean): String {
+        if (!snapshot) {
+            return ""
+        }
+        val commitHash = if (includeHash) {
+            getGitCommitHash(project)?.let { "+$it" } ?: ""
+        } else {
+            ""
+        }
+        return "$commitHash-SNAPSHOT"
+    }
+
+    group = "me.caseload.knockbacksync"
+    version = "$fullVersion${getVersionMeta(true)}"
+    ext["versionNoHash"] = "$fullVersion${getVersionMeta(false)}"
+    ext["githubRepo"] = githubRepo
+
+    repositories {
+//        mavenLocal()
+        maven("https://repo.grim.ac/snapshots")
+        mavenCentral()
+        maven("https://hub.spigotmc.org/nexus/content/repositories/snapshots/")
+        maven("https://repo.codemc.io/repository/maven-releases/")
+        maven("https://repo.opencollab.dev/maven-snapshots/")
+        maven("https://repo.papermc.io/repository/maven-public/")
+        maven(url = "https://maven.fabricmc.net/") {
+            name = "Fabric"
+        }
+        maven("https://libraries.minecraft.net/")
+        maven("https://maven.neoforged.net/releases")
+    }
+}
+
+subprojects {
+    apply(plugin = "java")
+
+    java {
+        sourceCompatibility = JavaVersion.VERSION_1_8
+        targetCompatibility = JavaVersion.VERSION_1_8
+    }
+}
+
+tasks.jar {
+    // The root project has no plugin entrypoint; do not emit an empty deployable-looking JAR.
+    enabled = false
+}
+
+val copyBukkitPluginJar by tasks.registering(Copy::class) {
+    val bukkitShadowJar = project(":bukkit").tasks.named<ShadowJar>("shadowJar")
+
+    dependsOn(bukkitShadowJar)
+    from(bukkitShadowJar.flatMap { it.archiveFile })
+    into(layout.buildDirectory.dir("libs"))
+    rename { "KnockbackSync-OG-$fullVersion${if (snapshot) "-SNAPSHOT" else ""}.jar" }
+}
+
+tasks.assemble {
+    dependsOn(copyBukkitPluginJar)
+}

bukkit/build.gradle.kts

@@ -0,0 +1,90 @@
+import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
+
+plugins {
+    id("com.gradleup.shadow")
+}
+
+val shadePE: Boolean by rootProject.extra
+
+base {
+    archivesName.set("${rootProject.property("archives_base_name")}-bukkit${if (shadePE) "" else "-lite"}")
+}
+
+val shadeThisThing: Configuration by configurations.creating {
+    isCanBeConsumed = true
+    isTransitive = true
+}
+
+// TODO migrate to only including sources sets for compile, test and javadoc tasks
+tasks.withType<JavaCompile>().configureEach {
+    source(project(":common").sourceSets.main.get().allSource)
+}
+
+tasks.withType<Javadoc>().configureEach {
+    source(project(":common").sourceSets.main.get().allJava)
+}
+
+tasks.named<JavaCompile>("compileTestJava") {
+    exclude("**/*")
+}
+
+dependencies {
+    implementation(project(":common"))
+
+    compileOnly("org.spigotmc:spigot-api:1.18.2-R0.1-SNAPSHOT")
+    compileOnly("org.geysermc.floodgate:api:2.0-SNAPSHOT")
+    compileOnly("io.netty:netty-all:4.1.72.Final")
+
+    compileOnly("org.projectlombok:lombok:1.18.34")
+    annotationProcessor("org.projectlombok:lombok:1.18.34")
+
+    shadeThisThing(implementation("org.kohsuke:github-api:1.326")!!)
+    if (shadePE) {
+        shadeThisThing(implementation("com.github.retrooper:packetevents-spigot:2.11.2")!!)
+    } else {
+        compileOnly("com.github.retrooper:packetevents-spigot:2.11.2")
+    }
+    shadeThisThing(implementation("org.incendo:cloud-paper:2.0.0-beta.14")!!)
+    shadeThisThing(implementation("org.incendo:cloud-core:2.0.0")!!)
+
+    // Required for 1.14.4 support because gson is too old to have JosnParser.parseString()
+    shadeThisThing(implementation("com.google.code.gson:gson:2.11.0")!!)
+}
+
+tasks.withType<ShadowJar> {
+    manifest {
+        attributes["paperweight-mappings-namespace"] = "mojang"
+    }
+
+    // Remove the -all suffix from the output JAR file name
+    archiveClassifier.set("")
+
+    configurations = listOf(shadeThisThing)
+    enableAutoRelocation = true
+    relocationPrefix = "${project.property("maven_group")}.${project.property("archives_base_name")}.shaded"
+}
+
+tasks.jar {
+    // The shaded archive is the runtime plugin; do not emit a misleading thin plugin JAR.
+    enabled = false
+}
+
+tasks.build {
+    dependsOn(tasks.shadowJar)
+}
+
+tasks.processResources {
+    from(project(":common").sourceSets.main.get().resources)
+    inputs.property("version", project.version)
+    inputs.property("shadePE", shadePE) // Add shadePE as an input to trigger reprocessing if it changes
+    filteringCharset = "UTF-8"
+
+
+    filesMatching("plugin.yml") {
+        expand(
+            "version" to project.version,
+            // Bukkit accepts `depend` only; `depends` is silently ignored.
+            "depend" to if (shadePE) "[]" else listOf("PacketEvents")
+        )
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/BukkitBase.java

@@ -0,0 +1,272 @@
+package me.caseload.knockbacksync;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import com.github.retrooper.packetevents.protocol.world.Location;
+import io.github.retrooper.packetevents.factory.spigot.SpigotPacketEventsBuilder;
+import me.caseload.knockbacksync.common.BuildConfig;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.listener.bukkit.*;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.permission.PermissionChecker;
+import me.caseload.knockbacksync.permission.PluginPermissionChecker;
+import me.caseload.knockbacksync.scheduler.BukkitSchedulerAdapter;
+import me.caseload.knockbacksync.scheduler.FoliaSchedulerAdapter;
+import me.caseload.knockbacksync.sender.BukkitPlayerSelectorParser;
+import me.caseload.knockbacksync.sender.BukkitSenderFactory;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.stats.custom.BukkitStatsManager;
+import me.caseload.knockbacksync.stats.custom.PluginJarHashProvider;
+import me.caseload.knockbacksync.world.BukkitServer;
+import org.bukkit.Bukkit;
+import org.bukkit.Server;
+import org.bukkit.World;
+import org.bukkit.configuration.file.FileConfiguration;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.entity.Player;
+import org.bukkit.event.Listener;
+import org.bukkit.plugin.PluginManager;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.bukkit.util.Vector;
+import org.incendo.cloud.bukkit.CloudBukkitCapabilities;
+import org.incendo.cloud.execution.ExecutionCoordinator;
+import org.incendo.cloud.paper.LegacyPaperCommandManager;
+
+import java.io.File;
+import java.io.InputStream;
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.invoke.MethodType;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.net.URL;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.Map;
+import java.util.logging.Logger;
+
+public class BukkitBase extends Base {
+
+    private final JavaPlugin plugin;
+    private final BukkitSenderFactory bukkitSenderFactory = new BukkitSenderFactory(this);
+    private final PluginPermissionChecker permissionChecker = new PluginPermissionChecker();
+
+    private int playerUpdateInterval;
+
+    private final MethodHandle tickRateMethodHandle;
+
+    public BukkitBase(JavaPlugin plugin) {
+        this.plugin = plugin;
+        super.configManager = new ConfigManager();
+        super.playerSelectorParser = new BukkitPlayerSelectorParser<>();
+        super.statsManager = new BukkitStatsManager(plugin);
+        super.platformServer = new BukkitServer();
+        super.pluginJarHashProvider = new PluginJarHashProvider(this.getClass().getProtectionDomain().getCodeSource().getLocation());
+        this.playerUpdateInterval = this.getConfigManager().getConfigWrapper().getInt("entity_tick_intervals.player", 2);
+
+        MethodHandle handle = null;
+        try {
+            Server craftServer = Bukkit.getServer();
+            MethodHandles.Lookup lookup = MethodHandles.lookup();
+
+            // Get handle for getServerTickManager
+            MethodHandle getServerTickManager = lookup.findVirtual(craftServer.getClass(),
+                    "getServerTickManager", MethodType.methodType(Object.class));
+
+            Object serverTickManager = getServerTickManager.invoke(craftServer);
+
+            // Get handle for getTickRate
+            handle = lookup.findVirtual(serverTickManager.getClass(),
+                    "getTickRate", MethodType.methodType(float.class));
+
+        } catch (Throwable t) {
+            // If anything fails, handle will remain null
+        }
+        this.tickRateMethodHandle = handle;
+    }
+
+    @Override
+    public Logger getLogger() {
+        return this.plugin.getLogger();
+    }
+
+    @Override
+    public File getDataFolder() {
+        return this.plugin.getDataFolder();
+    }
+
+    @Override
+    public InputStream getResource(String filename) {
+        return this.plugin.getResource(filename);
+    }
+
+    @Override
+    public void load() {
+        // External-provider mode delegates PacketEvents lifecycle to the installed PE plugin.
+        if (!BuildConfig.SHADE_PE) {
+            return;
+        }
+        PacketEvents.setAPI(SpigotPacketEventsBuilder.build(this.plugin));
+        PacketEvents.getAPI().load();
+    }
+
+    @Override
+    public void enable() {
+        super.enable();
+        super.eventBus.registerListeners(this);
+        if (PacketEvents.getAPI().getServerManager().getVersion().isNewerThanOrEquals(ServerVersion.V_1_20_5) && this.getPlatform() == Platform.BUKKIT) {
+            scheduler.runTaskTimerAsynchronously(this::setUpdateIntervals, 1, 1);
+        }
+    }
+
+    @Override
+    public void initializeScheduler() {
+        switch (getPlatform()) {
+            case BUKKIT:
+                super.scheduler = new BukkitSchedulerAdapter(this.plugin);
+                break;
+            case FOLIA:
+                super.scheduler = new FoliaSchedulerAdapter(this.plugin);
+                break;
+        }
+    }
+
+    @Override
+    protected void registerPlatformListeners() {
+        registerPluginListeners(
+                new BukkitPlayerDamageListener(),
+                new BukkitPlayerKnockbackListener(),
+                new me.caseload.knockbacksync.listener.bukkit.KnockbackResistanceNullifier()
+        );
+        // Reconcile away any leftover owned knockback-resistance marker for players already
+        // online (e.g. across a /reload), so none is stranded.
+        me.caseload.knockbacksync.listener.bukkit.KnockbackResistanceNullifier.cleanupAll();
+    }
+
+    @Override
+    protected void registerCommands() {
+        super.commandManager = new LegacyPaperCommandManager<>(
+                this.plugin,
+                ExecutionCoordinator.simpleCoordinator(),
+                bukkitSenderFactory
+        );
+        if (commandManager instanceof LegacyPaperCommandManager) {
+            LegacyPaperCommandManager<Sender> legacyPaperCommandManager = (LegacyPaperCommandManager<Sender>) commandManager;
+            if (legacyPaperCommandManager.hasCapability(CloudBukkitCapabilities.NATIVE_BRIGADIER)) {
+                legacyPaperCommandManager.registerBrigadier();
+            } else if (commandManager.hasCapability(CloudBukkitCapabilities.ASYNCHRONOUS_COMPLETION)) {
+                legacyPaperCommandManager.registerAsynchronousCompletions();
+            }
+        }
+        super.registerCommands();
+    }
+
+    @Override
+    protected String getVersion() {
+        return this.plugin.getDescription().getVersion();
+    }
+
+    @Override
+    public void saveDefaultConfig() {
+        this.plugin.saveDefaultConfig();
+    }
+
+    @Override
+    public PermissionChecker getPermissionChecker() {
+        return permissionChecker;
+    }
+
+    @Override
+    public float getTickRate() {
+        if (tickRateMethodHandle != null) {
+            try {
+                return (float) tickRateMethodHandle.invoke();
+            } catch (Throwable t) {
+                return 20.0f;
+            }
+        }
+        return 20.0f;
+    }
+
+    public URL getJarURL() {
+        try {
+            String path = getClass().getProtectionDomain().getCodeSource().getLocation().getPath();
+            File pluginJarFile = new File(path);
+
+            return Paths.get(getDataFolder().getParentFile().getAbsolutePath(), pluginJarFile.getName()).toUri().toURL();
+        } catch (Exception e) {
+            LOGGER.severe("Couldn't find plugin file: " + e.getMessage());
+            return null;
+        }
+    }
+
+    private void registerPluginListeners(Listener... listeners) {
+        PluginManager pluginManager = this.plugin.getServer().getPluginManager();
+        for (Listener listener : listeners)
+            pluginManager.registerEvents(listener, this.plugin);
+    }
+
+    public BukkitSenderFactory getSenderFactory() {
+        return this.bukkitSenderFactory;
+    }
+
+    public void setUpdateIntervals() {
+        try {
+            for (World world : Bukkit.getWorlds()) {
+                Method getWorldHandleMethod = world.getClass().getMethod("getHandle");
+                Object serverLevel = getWorldHandleMethod.invoke(world);
+
+                // Get ChunkMap
+                Method getChunkSource = serverLevel.getClass().getMethod("getChunkSource");
+                Object chunkSource = getChunkSource.invoke(serverLevel);
+                Field chunkMapField = chunkSource.getClass().getDeclaredField("chunkMap");
+                chunkMapField.setAccessible(true);
+                Object chunkMap = chunkMapField.get(chunkSource);
+
+                // Get entityMap from ChunkMap
+                Field entityMapField = chunkMap.getClass().getDeclaredField("entityMap");
+                entityMapField.setAccessible(true);
+                Map<Integer, ?> entityMap = (Map<Integer, ?>) entityMapField.get(chunkMap);
+                for (Player player : Bukkit.getOnlinePlayers()) {
+                    Object trackedEntity = entityMap.get(player.getEntityId());
+                    if (trackedEntity == null)
+                        continue;
+
+                    Field serverEntityField = trackedEntity.getClass().getDeclaredField("serverEntity");
+                    serverEntityField.setAccessible(true);
+                    Object serverEntity = serverEntityField.get(trackedEntity);
+
+                    Field updateIntervalField = serverEntity.getClass().getDeclaredField("updateInterval");
+                    updateIntervalField.setAccessible(true);
+                    updateIntervalField.set(serverEntity, playerUpdateInterval);
+                }
+            }
+        } catch (NoSuchMethodException | InvocationTargetException | IllegalAccessException | NoSuchFieldException e) {
+            throw new IllegalStateException("Unable to use reflection to modify updateIntervals" + e);
+        }
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReload(ConfigReloadEvent event) {
+        playerUpdateInterval = event.getConfigManager().getConfigWrapper().getInt("entity_tick_intervals.player", 2);
+    }
+
+    public void restartServer() {
+        Bukkit.dispatchCommand(Bukkit.getConsoleSender(), "restart");
+    }
+
+    public boolean hasRestartScript() {
+        File spigotFile = new File("spigot.yml");
+        if (!spigotFile.exists())
+            return false;
+
+        FileConfiguration spigotConfig = YamlConfiguration.loadConfiguration(spigotFile);
+        String scriptValue = spigotConfig.getString("settings.restart-script");
+        if (scriptValue == null || scriptValue.isEmpty())
+            return false;
+
+        return Paths.get(scriptValue).toAbsolutePath().normalize().toFile().exists();
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/BukkitLoaderPlugin.java

@@ -0,0 +1,33 @@
+package me.caseload.knockbacksync;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import me.caseload.knockbacksync.common.BuildConfig;
+import org.bukkit.plugin.java.JavaPlugin;
+
+public final class BukkitLoaderPlugin extends JavaPlugin {
+
+    private final Base core = new BukkitBase(this);
+
+    @Override
+    public void onLoad() {
+        core.load();
+    }
+
+    @Override
+    public void onEnable() {
+        core.enable();
+    }
+
+    @Override
+    public void onDisable() {
+        // Reconcile away any leftover owned knockback-resistance marker so no player is left
+        // with reduced resistance after the plugin unloads.
+        me.caseload.knockbacksync.listener.bukkit.KnockbackResistanceNullifier.cleanupAll();
+        // Drop listener handles before any lifecycle decision; the shared API may outlive this plugin.
+        core.unregisterPacketListeners();
+        // Terminate only when this plugin owns the PacketEvents lifecycle (shaded build).
+        if (BuildConfig.SHADE_PE) {
+            PacketEvents.getAPI().terminate();
+        }
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/api/KnockbackSyncRodApi.java

@@ -0,0 +1,67 @@
+package me.caseload.knockbacksync.api;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import org.bukkit.entity.Player;
+import org.bukkit.util.Vector;
+
+/**
+ * Stable, reflection-friendly entry point for other plugins (notably OldCombatMechanics'
+ * old-fishing-knockback module) to hand KnockbackSync a pre-computed knockback vector, so that
+ * KnockbackSync owns the final velocity and applies the same latency Y-correction it gives melee
+ * knockback.
+ *
+ * <p>Why this exists: a fishing-rod hit reaches KnockbackSync as an ordinary player-vs-player
+ * damage event. KnockbackSync cannot tell it apart from a sword hit, so it computes a melee vector
+ * and the caller's own {@code setVelocity} either fights it or is re-corrected with melee-tuned
+ * latency logic — the rod pop ends up flattened/inconsistent under latency. Routing the
+ * bobber-direction vector through here makes the rod feel like 1.8, latency-synced like melee.</p>
+ *
+ * <p>Resolved by callers via reflection; keep the class name, package, and method signature
+ * stable.</p>
+ */
+public final class KnockbackSyncRodApi {
+
+    private KnockbackSyncRodApi() {
+    }
+
+    /**
+     * Registers a fishing-rod knockback vector for {@code victim}, to be applied and latency-synced
+     * by the {@code PlayerVelocityEvent} produced by the caller's subsequent damage tick.
+     *
+     * <p>MUST be called on the main thread, immediately before the caller deals the rod's damage.</p>
+     *
+     * @param victim        the player being knocked back
+     * @param rodKnockback  the 1.8 bobber-direction knockback vector
+     * @return {@code true} if KnockbackSync will own this knockback (caller must NOT also call
+     *         {@code setVelocity}); {@code false} if KnockbackSync is disabled or not tracking this
+     *         player, in which case the caller should apply the knockback itself.
+     */
+    public static boolean applyRodKnockback(Player victim, Vector rodKnockback) {
+        if (victim == null || rodKnockback == null) return false;
+
+        final Base base = Base.INSTANCE;
+        if (base == null) return false;
+
+        final ConfigManager config = base.getConfigManager();
+        if (config == null || !config.isToggled() || !config.isLegacyKnockbackEnabled())
+            return false;
+
+        final User user = new BukkitPlayer(victim).getUser();
+        if (user == null) return false;
+
+        final PlayerData playerData = PlayerDataManager.getPlayerData(user);
+        if (playerData == null) return false; // not tracked (exempt/Geyser/etc.) — caller falls back
+
+        final Vector3d kb = new Vector3d(rodKnockback.getX(), rodKnockback.getY(), rodKnockback.getZ());
+        playerData.setRodKnockback(kb);
+        // On-ground sync should target the rod's vertical, mirroring the melee damage path.
+        playerData.setVerticalVelocity(kb.getY());
+        return true;
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/listener/bukkit/BukkitPlayerDamageListener.java

@@ -0,0 +1,67 @@
+package me.caseload.knockbacksync.listener.bukkit;
+
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.listener.PlayerDamageListener;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.util.MultiLibUtil;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.entity.EntityDamageByEntityEvent;
+
+public class BukkitPlayerDamageListener extends PlayerDamageListener implements Listener {
+
+    /**
+     * D3 — projectile PvP knockback-resistance nullification.
+     *
+     * <p>For a hit that {@link PvpSource} classifies as {@code PROJECTILE} PvP, zero the
+     * victim's effective knockback resistance BEFORE vanilla computes the knockback, so a
+     * netherite victim takes full (diamond-level) projectile knockback. Runs at {@code LOW}
+     * so it precedes OCM's {@code projectile-knockback} damage raise ({@code NORMAL}) and
+     * vanilla knockback. The decision is gated on classification + config only — never on the
+     * current event damage, because OCM may not have raised snowball/egg/ender-pearl damage
+     * yet at this priority.</p>
+     */
+    @EventHandler(priority = EventPriority.LOW, ignoreCancelled = true)
+    public void onProjectilePvpDamage(EntityDamageByEntityEvent event) {
+        final ConfigManager config = Base.INSTANCE.getConfigManager();
+        // Single source of truth: active only when toggled on, legacy knockback enabled,
+        // and knockback resistance is NOT being kept (matching OCM's default).
+        if (!config.isToggled() || !config.isLegacyKnockbackEnabled() || config.isLegacyKnockbackResistanceEnabled())
+            return;
+
+        if (PvpSource.classify(event) != PvpSource.Type.PROJECTILE)
+            return;
+
+        final Player victim = (Player) event.getEntity();
+        if (MultiLibUtil.isExternalPlayer(victim))
+            return;
+
+        KnockbackResistanceNullifier.nullify(victim);
+    }
+
+    /**
+     * Melee PvP: KnockbackSync owns the 1.8 melee velocity via {@code LegacyKnockback}
+     * (applied at {@code PlayerVelocityEvent}), so melee already delivers full knockback
+     * without touching the resistance attribute. The previous {@code stripKnockbackResistance()}
+     * (which removed the victim's {@code KNOCKBACK_RESISTANCE} modifiers and never restored them,
+     * leaking into PvE) has been deleted. Projectile/explosion/fishing hits are NOT routed
+     * through this melee path (their damager is not a player), so no stale legacy-knockback
+     * vector can be stored for them.
+     */
+    @EventHandler(ignoreCancelled = true)
+    public void onPlayerDamage(EntityDamageByEntityEvent event) {
+        Entity victim = event.getEntity();
+        Entity attacker = event.getDamager();
+        if (!(victim instanceof Player) || !(attacker instanceof Player))
+            return;
+
+        if (MultiLibUtil.isExternalPlayer((Player) victim))
+            return;
+
+        onPlayerDamage(new BukkitPlayer((Player) victim), new BukkitPlayer((Player) attacker));
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/listener/bukkit/BukkitPlayerKnockbackListener.java

@@ -0,0 +1,48 @@
+package me.caseload.knockbacksync.listener.bukkit;
+
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.listener.PlayerKnockbackListener;
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.util.MultiLibUtil;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+import org.bukkit.event.entity.EntityDamageByEntityEvent;
+import org.bukkit.event.entity.EntityDamageEvent;
+import org.bukkit.event.player.PlayerVelocityEvent;
+import org.bukkit.util.Vector;
+
+public class BukkitPlayerKnockbackListener extends PlayerKnockbackListener implements Listener {
+
+    // HIGHEST so KnockbackSync is the last writer in the event chain: it owns the final
+    // melee velocity. We read and write the EVENT velocity (not player.getVelocity()/
+    // player.setVelocity()) so we integrate with the chain instead of fighting it. See
+    // knockback-sync issue #7 (kernitus, Krymonota, Axionize).
+    @EventHandler(priority = EventPriority.HIGHEST, ignoreCancelled = true)
+    public void onPlayerVelocity(PlayerVelocityEvent event) {
+        Player victim = event.getPlayer();
+        EntityDamageEvent entityDamageEvent = victim.getLastDamageCause();
+        if (entityDamageEvent == null)
+            return;
+
+        EntityDamageEvent.DamageCause damageCause = entityDamageEvent.getCause();
+        if (damageCause != EntityDamageEvent.DamageCause.ENTITY_ATTACK)
+            return;
+
+        Entity attacker = ((EntityDamageByEntityEvent) entityDamageEvent).getDamager();
+        if (!(attacker instanceof Player))
+            return;
+
+        if (MultiLibUtil.isExternalPlayer(victim))
+            return;
+
+        Vector eventVelocity = event.getVelocity();
+        Vector3d result = onPlayerVelocity(new BukkitPlayer(victim),
+                new Vector3d(eventVelocity.getX(), eventVelocity.getY(), eventVelocity.getZ()));
+
+        if (result != null)
+            event.setVelocity(new Vector(result.getX(), result.getY(), result.getZ()));
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/listener/bukkit/KnockbackResistanceNullifier.java

@@ -0,0 +1,121 @@
+package me.caseload.knockbacksync.listener.bukkit;
+
+import me.caseload.knockbacksync.Base;
+import org.bukkit.Bukkit;
+import org.bukkit.attribute.Attribute;
+import org.bukkit.attribute.AttributeInstance;
+import org.bukkit.attribute.AttributeModifier;
+import org.bukkit.entity.Player;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerJoinEvent;
+import org.bukkit.event.player.PlayerQuitEvent;
+
+import java.util.UUID;
+
+/**
+ * D3 — Resistance Nullification (M1).
+ *
+ * <p>For player-vs-player projectile hits (classified by {@link PvpSource}), forces the
+ * victim's effective {@code generic.knockback_resistance} to 0 for the duration of the
+ * hit by adding a single plugin-owned {@code MULTIPLY_SCALAR_1} {@code -1.0} modifier,
+ * lets vanilla compute full knockback, then removes the owned marker on the next tick.
+ * Equipment and other plugins' modifiers are never read, captured, or removed — only the
+ * owned marker (identified by a constant UUID) is added/removed.</p>
+ *
+ * <p>Melee PvP is owned by {@code LegacyKnockback} (which already ignores resistance when
+ * {@code enable_knockback_resistance=false}) and needs no attribute work; fishing PvP is
+ * owned by OCM's {@code old-fishing-knockback}. Explosions are out of scope on 1.19.4.</p>
+ *
+ * <p>The marker is permanent NMS state until removed, so a leftover marker is reconciled
+ * away on join/quit and on plugin enable/disable (see {@link #cleanupAll()}), guaranteeing
+ * a player is never left permanently with reduced resistance.</p>
+ */
+public final class KnockbackResistanceNullifier implements Listener {
+
+    // Constant, plugin-owned modifier identity. Add skips if this UUID is already present;
+    // removal matches by this UUID. Equipment/foreign modifiers are never touched.
+    private static final UUID MODIFIER_UUID = UUID.fromString("7b2a1c84-4d3e-4f0a-9c6b-1e5a9d8c7f30");
+    private static final String MODIFIER_NAME = "knockbacksync_pvp_kb_nullify";
+
+    // Mirrors the previous stripKnockbackResistance guard: if the attribute is unavailable
+    // on this server version, disable for the session and warn once (no per-hit log spam).
+    private static volatile boolean unsupported = false;
+
+    /**
+     * Force the victim's effective knockback resistance to 0 for the current hit by adding the
+     * owned marker, then schedule its removal on the next tick. Idempotent and re-entrancy safe:
+     * if the marker is already present (e.g. a second hit in the same tick) the add is skipped.
+     *
+     * <p>Must be called before vanilla computes the hit's knockback (i.e. during the damage
+     * event at an early priority).</p>
+     */
+    public static void nullify(Player victim) {
+        final AttributeInstance attribute = resolve(victim);
+        if (attribute == null) return;
+        if (hasOwnedModifier(attribute)) return;
+
+        try {
+            attribute.addModifier(new AttributeModifier(
+                    MODIFIER_UUID, MODIFIER_NAME, -1.0, AttributeModifier.Operation.MULTIPLY_SCALAR_1));
+        } catch (IllegalArgumentException alreadyApplied) {
+            return; // raced — modifier already present; nothing to add
+        }
+
+        // Remove on the NEXT tick. Same-event (MONITOR/finally) removal is forbidden: vanilla
+        // computes the knockback after the event returns, so an in-event removal would restore
+        // the attribute before vanilla reads it. On the non-Folia target this is a main-thread
+        // next-tick task; it stays compile-safe (no Player#getScheduler()).
+        Base.INSTANCE.getScheduler().runTaskLater(() -> remove(victim), 1L);
+    }
+
+    /** Remove the owned marker if present. Idempotent; never touches foreign/equipment modifiers. */
+    public static void remove(Player victim) {
+        final AttributeInstance attribute = resolve(victim);
+        if (attribute == null) return;
+        for (AttributeModifier modifier : attribute.getModifiers()) {
+            if (MODIFIER_UUID.equals(modifier.getUniqueId())) {
+                attribute.removeModifier(modifier);
+            }
+        }
+    }
+
+    /** Strip the owned marker from every online player (plugin enable/disable reconciliation). */
+    public static void cleanupAll() {
+        for (Player player : Bukkit.getOnlinePlayers()) {
+            remove(player);
+        }
+    }
+
+    private static boolean hasOwnedModifier(AttributeInstance attribute) {
+        for (AttributeModifier modifier : attribute.getModifiers()) {
+            if (MODIFIER_UUID.equals(modifier.getUniqueId())) return true;
+        }
+        return false;
+    }
+
+    private static AttributeInstance resolve(Player victim) {
+        if (unsupported || victim == null) return null;
+        try {
+            return victim.getAttribute(Attribute.GENERIC_KNOCKBACK_RESISTANCE);
+        } catch (Throwable t) {
+            unsupported = true;
+            Base.INSTANCE.getLogger().warning(
+                    "Could not access KNOCKBACK_RESISTANCE attribute; PvP knockback-resistance "
+                            + "nullification disabled for this session: " + t.getMessage());
+            return null;
+        }
+    }
+
+    // ── R7 fail-safe: reconcile away any leftover owned marker ──────────────────────────────
+
+    @EventHandler
+    public void onJoin(PlayerJoinEvent event) {
+        remove(event.getPlayer());
+    }
+
+    @EventHandler
+    public void onQuit(PlayerQuitEvent event) {
+        remove(event.getPlayer());
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/listener/bukkit/PvpSource.java

@@ -0,0 +1,85 @@
+package me.caseload.knockbacksync.listener.bukkit;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import org.bukkit.entity.Entity;
+import org.bukkit.entity.Player;
+import org.bukkit.entity.Projectile;
+import org.bukkit.event.entity.EntityDamageByEntityEvent;
+import org.bukkit.projectiles.ProjectileSource;
+
+/**
+ * D1 — PvP Source Attribution.
+ *
+ * <p>Classifies a damage event on a player victim into a source class so the
+ * knockback-resistance nullifier (D3) knows whether and how to act. Attribution is
+ * self-inclusive: the victim's own projectile (e.g. their own arrow) still counts as
+ * PvP. This classifier only answers "is this player-attributed, and by what source
+ * class?" — it does not modify damage or knockback.</p>
+ *
+ * <p>Scope note (Purpur 1.19.4 target): netherite {@code generic.knockback_resistance}
+ * only reduces knockback applied through {@code LivingEntity.knockback(...)} (melee and
+ * projectile). Explosion knockback is not reduced by it on 1.19.4 (Blast Protection
+ * governs that), and wind charges do not exist, so explosion/wind-charge sources are
+ * classified {@link Type#NONE}.</p>
+ */
+public final class PvpSource {
+
+    public enum Type {
+        /** Direct player melee. Owned by {@code LegacyKnockback}; no attribute nullification. */
+        MELEE,
+        /** Player-shot projectile (arrow, spectral arrow, trident, snowball, egg, ender pearl, ...). Nullified by D3. */
+        PROJECTILE,
+        /** Fishing-rod hit (OCM {@code old-fishing-knockback}); owned by the rod sync. No nullification. */
+        FISHING,
+        /** Not attributable to a player (mob, environment, explosion, ...). */
+        NONE
+    }
+
+    private PvpSource() {
+    }
+
+    /**
+     * @param event a damage-by-entity event (the caller has not necessarily checked the victim type)
+     * @return the PvP source class; {@link Type#NONE} when the damage is not attributable to a player
+     */
+    public static Type classify(EntityDamageByEntityEvent event) {
+        if (!(event.getEntity() instanceof Player)) return Type.NONE;
+        final Player victim = (Player) event.getEntity();
+        final Entity damager = event.getDamager();
+
+        // Direct player damager: either a melee hit, or an OCM fishing-rod hit.
+        // old-fishing-knockback deals its damage via damage(victim, rodder), so the
+        // damager is the rodding player (not the bobber). Distinguish the rod hit via
+        // the rod-pending marker KnockbackSync stores for the rod path. Both MELEE and
+        // FISHING are owned elsewhere and get no attribute nullification, so a mislabel
+        // between the two cannot change knockback behaviour.
+        if (damager instanceof Player) {
+            return isRodPending(victim) ? Type.FISHING : Type.MELEE;
+        }
+
+        // Player-shot projectile, resolved generically via ProjectileSource so any
+        // player-shot projectile type is covered without a per-type list (including
+        // types absent from the compile-time API). Self-inclusive: the shooter may be
+        // the victim. A non-player projectile source (e.g. a dispenser's
+        // BlockProjectileSource) or a null shooter is not PvP. Note: the ender pearl's
+        // post-teleport fall damage is a separate non-by-entity event, so it never
+        // reaches this projectile branch.
+        if (damager instanceof Projectile) {
+            final ProjectileSource shooter = ((Projectile) damager).getShooter();
+            return (shooter instanceof Player) ? Type.PROJECTILE : Type.NONE;
+        }
+
+        // Explosions (TNT, end crystal, fireball), mobs, environment: out of scope on 1.19.4.
+        return Type.NONE;
+    }
+
+    private static boolean isRodPending(Player victim) {
+        final User user = new BukkitPlayer(victim).getUser();
+        if (user == null) return false;
+        final PlayerData data = PlayerDataManager.getPlayerData(user);
+        return data != null && data.isRodKnockbackPending();
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/permission/PluginPermissionChecker.java

@@ -0,0 +1,39 @@
+package me.caseload.knockbacksync.permission;
+
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.sender.Sender;
+import org.bukkit.command.CommandSender;
+import org.bukkit.entity.Player;
+
+public class PluginPermissionChecker implements PermissionChecker {
+
+//    Method getBukkitSenderMethod;
+//
+//    public PluginPermissionChecker() {
+//        try {
+//            getBukkitSenderMethod = CommandSourceStack.class.getMethod("getBukkitSender");
+//        } catch (NoSuchMethodException e) {
+//            e.printStackTrace();
+//        }
+//    }
+
+    // Currently shouldn't be called
+    @Override
+    public boolean hasPermission(Object nativeType, String s, boolean defaultIfUnset) {
+        if (nativeType instanceof CommandSender) {
+            return ((CommandSender) nativeType).hasPermission(s);
+        }
+        throw new IllegalArgumentException("Attempted to check permission of an object that wasn't a platformplayer or Sender. This should never happen on Bukkit!");
+    }
+
+    @Override
+    public boolean hasPermission(Sender source, String s, boolean defaultIfUnset) {
+        return source.hasPermission(s, defaultIfUnset);
+    }
+
+    @Override
+    public boolean hasPermission(PlatformPlayer platformPlayer, String s) {
+        return ((BukkitPlayer) platformPlayer).bukkitPlayer.hasPermission(s);
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/player/BukkitPlayer.java

@@ -0,0 +1,245 @@
+package me.caseload.knockbacksync.player;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.protocol.world.BoundingBox;
+import com.github.retrooper.packetevents.util.Vector3d;
+import com.google.common.base.Preconditions;
+import me.caseload.knockbacksync.BukkitBase;
+import me.caseload.knockbacksync.Platform;
+import me.caseload.knockbacksync.world.FoliaWorld;
+import me.caseload.knockbacksync.world.PlatformWorld;
+import me.caseload.knockbacksync.world.SpigotWorld;
+import org.bukkit.Bukkit;
+import org.bukkit.enchantments.Enchantment;
+import org.bukkit.entity.Player;
+import org.bukkit.potion.PotionEffect;
+import org.bukkit.potion.PotionEffectType;
+import org.bukkit.util.Vector;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.UUID;
+
+public class BukkitPlayer implements PlatformPlayer {
+    public final Player bukkitPlayer;
+    public final User user;
+    private String clientBrand = "vanilla";
+
+    // Reflection variables
+    private static Class<?> craftPlayerClass;
+    private static Method getHandleMethod;
+    private static Method getAttackStrengthScaleMethod;
+    private static final ServerVersion currentVersion = PacketEvents.getAPI().getServerManager().getVersion();
+
+    // 1.12.2 support
+    static {
+        try {
+            // Check the current server version
+
+            // If the version is greater than 1.14.4, use the Player method directly
+            if (currentVersion.isOlderThan(ServerVersion.V_1_15)) {
+                Object server = Bukkit.getServer().getClass().getDeclaredMethod("getServer").invoke(Bukkit.getServer());
+                String nmsPackage = server.getClass().getPackage().getName();
+                String bukkitPackage = Bukkit.getServer().getClass().getPackage().getName();
+
+                // Step 1: Load the CraftPlayer class
+                craftPlayerClass = Class.forName(bukkitPackage + ".entity.CraftPlayer");
+                // Step 2: Get the getHandle method
+                getHandleMethod = craftPlayerClass.getMethod("getHandle");
+                // Step 3: Get the getAttackStrengthScale method from the EntityPlayer class
+                Class<?> entityPlayerClass = Class.forName(nmsPackage + ".EntityPlayer");
+                String getAttackStrengthScaleMethodName = "";
+
+                // Determine the method name based on the version
+                if (currentVersion.isOlderThan(ServerVersion.V_1_13)) {
+                    getAttackStrengthScaleMethodName = "n";
+                } else if (currentVersion.isOlderThan(ServerVersion.V_1_14)) {
+                    getAttackStrengthScaleMethodName = "r";
+                } else if (currentVersion.isOlderThan(ServerVersion.V_1_15)) {
+                    getAttackStrengthScaleMethodName = "s";
+                }
+
+                // Get the attack strength scale method for EntityPlayer
+                getAttackStrengthScaleMethod = entityPlayerClass.getMethod(getAttackStrengthScaleMethodName, float.class);
+                getAttackStrengthScaleMethod.setAccessible(true);
+            }
+        } catch (ClassNotFoundException | NoSuchMethodException e) {
+            throw new IllegalStateException("Method of Class required to support this version not found via reflection" + e);
+        } catch (InvocationTargetException | IllegalAccessException e) {
+            throw new RuntimeException("Cannot access required methods via reflection to support this version" + e);
+        }
+    }
+
+    public BukkitPlayer(Player player) {
+        Preconditions.checkArgument(player != null);
+        this.bukkitPlayer = player;
+        this.user = PacketEvents.getAPI().getPlayerManager().getUser(bukkitPlayer);
+    }
+
+    @Override
+    public UUID getUUID() {
+        return bukkitPlayer.getUniqueId();
+    }
+
+    @Override
+    public String getName() {
+        return bukkitPlayer.getName();
+    }
+
+    @Override
+    public double getX() {
+        return bukkitPlayer.getLocation().getX();
+    }
+
+    @Override
+    public double getY() {
+        return bukkitPlayer.getLocation().getY();
+    }
+
+    @Override
+    public double getZ() {
+        return bukkitPlayer.getLocation().getZ();
+    }
+
+    @Override
+    public float getPitch() {
+        return bukkitPlayer.getLocation().getPitch();
+    }
+
+    @Override
+    public float getYaw() {
+        return bukkitPlayer.getLocation().getYaw();
+    }
+
+    @Override
+    public boolean isOnGround() {
+    /* Inconsistent with Entity.isOnGround()
+    /  Checks to see if this player is currently standing on a block.
+    /  This information may not be reliable, as it is a state provided by the client, and may therefore not be accurate.
+    /  It can also easily be spoofed. We may want to cast to LivingEntity and call isOnGround() instead
+    */
+        return bukkitPlayer.isOnGround();
+    }
+
+
+    @Override
+    public int getPing() {
+        if (currentVersion.isNewerThanOrEquals(ServerVersion.V_1_16_5)) {
+            return bukkitPlayer.getPing();
+        } else {
+            return PacketEvents.getAPI().getPlayerManager().getPing(bukkitPlayer);
+        }
+    }
+
+    @Override
+    public boolean isGliding() {
+        return bukkitPlayer.isGliding();
+    }
+
+    @Override
+    public PlatformWorld getWorld() {
+        return BukkitBase.INSTANCE.getPlatform() == Platform.FOLIA ? new FoliaWorld(bukkitPlayer.getWorld()): new SpigotWorld(bukkitPlayer.getWorld());
+    }
+
+    @Override
+    public Vector3d getLocation() {
+        org.bukkit.Location location = bukkitPlayer.getLocation();
+        return new Vector3d(location.getX(), location.getY(), location.getZ());
+    }
+
+    @Override
+    public void sendMessage(@NotNull String s) {
+        bukkitPlayer.sendMessage(s);
+    }
+
+    @Override
+    public double getAttackCooldown() {
+        if (currentVersion.isNewerThan(ServerVersion.V_1_14_4)) {
+            return bukkitPlayer.getAttackCooldown();
+        } else {
+            try {
+                // Step 1: Get the CraftPlayer instance
+                // Step 2: Get the handle (NMS EntityPlayer)
+                Object entityPlayer = getHandleMethod.invoke(bukkitPlayer);
+                // Step 3: Invoke the getAttackStrengthScale method
+                return (float) getAttackStrengthScaleMethod.invoke(entityPlayer, 0.5f);
+            } catch (Exception e) {
+                throw new IllegalStateException("This plugin will not work. NMS mapping for getAttackCooldown() failed!");
+            }
+        }
+    }
+
+    @Override
+    public boolean isSprinting() {
+        return bukkitPlayer.isSprinting();
+    }
+
+    @Override
+    public int getMainHandKnockbackLevel() {
+        return bukkitPlayer.getInventory().getItemInMainHand().getEnchantmentLevel(Enchantment.KNOCKBACK);
+    }
+
+    @Override
+    public int getWeaponKnockbackLevel() {
+        // OCM parity: use the main hand item, or the off hand when the main hand is empty.
+        org.bukkit.inventory.ItemStack mainHand = bukkitPlayer.getInventory().getItemInMainHand();
+        org.bukkit.inventory.ItemStack weapon = mainHand.getType() == org.bukkit.Material.AIR
+                ? bukkitPlayer.getInventory().getItemInOffHand()
+                : mainHand;
+        return weapon.getEnchantmentLevel(Enchantment.KNOCKBACK);
+    }
+
+    @Override
+    public @Nullable Integer getNoDamageTicks() {
+        return bukkitPlayer.getNoDamageTicks();
+    }
+
+    @Override
+    public void setVelocity(Vector3d adjustedVelocity) {
+        bukkitPlayer.setVelocity(new Vector(adjustedVelocity.x, adjustedVelocity.y, adjustedVelocity.z));
+    }
+
+    @Override
+    public Vector3d getVelocity() {
+        final Vector bukkitVelocity = bukkitPlayer.getVelocity();
+        return new Vector3d(bukkitVelocity.getX(), bukkitVelocity.getY(), bukkitVelocity.getZ());
+    }
+
+    @Override
+    public double getJumpPower() {
+        double jumpVelocity = 0.42;
+
+        PotionEffect jumpEffect = bukkitPlayer.getPotionEffect(PotionEffectType.JUMP);
+        if (jumpEffect != null) {
+            int amplifier = jumpEffect.getAmplifier();
+            jumpVelocity += (amplifier + 1) * 0.1F;
+        }
+
+        return jumpVelocity;
+    }
+
+    @Override
+    public BoundingBox getBoundingBox() {
+        org.bukkit.util.BoundingBox boundingBox = bukkitPlayer.getBoundingBox();
+        return new BoundingBox(boundingBox.getMinX(), boundingBox.getMinY(), boundingBox.getMinZ(), boundingBox.getMaxX(), boundingBox.getMaxY(), boundingBox.getMaxZ());
+    }
+
+    @Override
+    public @Nullable User getUser() {
+        return this.user;
+    }
+
+    @Override
+    public void setClientBrand(String brand) {
+        this.clientBrand = brand;
+    }
+
+    @Override
+    public String getClientBrand() {
+        return this.clientBrand;
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/scheduler/BukkitSchedulerAdapter.java

@@ -0,0 +1,51 @@
+package me.caseload.knockbacksync.scheduler;
+
+import org.bukkit.Bukkit;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.scheduler.BukkitScheduler;
+
+public class BukkitSchedulerAdapter implements SchedulerAdapter {
+    private final Plugin plugin;
+    private final BukkitScheduler scheduler;
+
+    public BukkitSchedulerAdapter(Plugin plugin) {
+        this.plugin = plugin;
+        this.scheduler = Bukkit.getScheduler();
+    }
+
+    @Override
+    public AbstractTaskHandle runTask(Runnable task) {
+        return new BukkitTaskHandle(scheduler.runTask(plugin, task));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskAsynchronously(Runnable task) {
+        return new BukkitTaskHandle(scheduler.runTaskAsynchronously(plugin, task));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskLater(Runnable task, long delayTicks) {
+        return new BukkitTaskHandle(scheduler.runTaskLater(plugin, task, delayTicks));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskTimer(Runnable task, long delayTicks, long periodTicks) {
+        return new BukkitTaskHandle(scheduler.runTaskTimer(plugin, task, delayTicks, periodTicks));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskLaterAsynchronously(Runnable task, long delay) {
+        return new BukkitTaskHandle(scheduler.runTaskLaterAsynchronously(plugin, task, delay));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskTimerAsynchronously(Runnable task, long delay, long period) {
+        return new BukkitTaskHandle(scheduler.runTaskTimerAsynchronously(plugin, task, delay, period));
+    }
+
+    // Bukkit should take care of this for us automatically
+    @Override
+    public void shutdown() {
+
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/scheduler/BukkitTaskHandle.java

@@ -0,0 +1,29 @@
+package me.caseload.knockbacksync.scheduler;
+
+import org.bukkit.plugin.Plugin;
+import org.bukkit.scheduler.BukkitTask;
+import org.jetbrains.annotations.NotNull;
+
+public class BukkitTaskHandle implements AbstractTaskHandle {
+    private final BukkitTask bukkitTask;
+    private boolean cancelled;
+
+    public BukkitTaskHandle(@NotNull BukkitTask bukkitTask) {
+        this.bukkitTask = bukkitTask;
+    }
+
+    public Plugin getOwner() {
+        return this.bukkitTask.getOwner();
+    }
+
+    @Override
+    public boolean getCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void cancel() {
+        this.bukkitTask.cancel();
+        this.cancelled = true;
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/scheduler/FoliaSchedulerAdapter.java

@@ -0,0 +1,51 @@
+package me.caseload.knockbacksync.scheduler;
+
+import io.github.retrooper.packetevents.util.folia.FoliaScheduler;
+import io.github.retrooper.packetevents.util.folia.GlobalRegionScheduler;
+import org.bukkit.plugin.Plugin;
+
+import java.util.concurrent.TimeUnit;
+
+public class FoliaSchedulerAdapter implements SchedulerAdapter {
+    private final Plugin plugin;
+
+    public FoliaSchedulerAdapter(Plugin plugin) {
+        this.plugin = plugin;
+    }
+
+    @Override
+    public AbstractTaskHandle runTask(Runnable task) {
+        return new FoliaTaskHandle(FoliaScheduler.getGlobalRegionScheduler().run(plugin, scheduledTask -> task.run()));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskAsynchronously(Runnable task) {
+        return new FoliaTaskHandle(FoliaScheduler.getAsyncScheduler().runNow(plugin, scheduledTask -> task.run()));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskLater(Runnable task, long delayTicks) {
+        return new FoliaTaskHandle(FoliaScheduler.getGlobalRegionScheduler().runDelayed(plugin, scheduledTask -> task.run(), delayTicks));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskTimer(Runnable task, long delayTicks, long periodTicks) {
+        return new FoliaTaskHandle(FoliaScheduler.getGlobalRegionScheduler().runAtFixedRate(plugin, scheduledTask -> task.run(), delayTicks, periodTicks));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskLaterAsynchronously(Runnable task, long delay) {
+        return new FoliaTaskHandle(FoliaScheduler.getAsyncScheduler().runDelayed(plugin, scheduledTask -> task.run(), delay * 50, TimeUnit.MILLISECONDS));
+    }
+
+    @Override
+    public AbstractTaskHandle runTaskTimerAsynchronously(Runnable task, long delay, long period) {
+        return new FoliaTaskHandle(FoliaScheduler.getAsyncScheduler().runAtFixedRate(plugin, scheduledTask -> task.run(), delay, period));
+    }
+
+    // Folia takes care of this
+    @Override
+    public void shutdown() {
+
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/scheduler/FoliaTaskHandle.java

@@ -0,0 +1,29 @@
+package me.caseload.knockbacksync.scheduler;
+
+import io.github.retrooper.packetevents.util.folia.TaskWrapper;
+import org.bukkit.plugin.Plugin;
+import org.jetbrains.annotations.NotNull;
+public class FoliaTaskHandle implements AbstractTaskHandle {
+
+    private final TaskWrapper scheduledTask; // Store as Object instead of ScheduledTask
+    private boolean cancelled;
+
+    public FoliaTaskHandle(@NotNull TaskWrapper scheduledTask) {
+        this.scheduledTask = scheduledTask;
+    }
+
+    public Plugin getOwner() {
+        return scheduledTask.getOwner();
+    }
+
+    @Override
+    public boolean getCancelled() {
+        return this.cancelled;
+    }
+
+    @Override
+    public void cancel() {
+        scheduledTask.cancel();
+        this.cancelled = true;
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/sender/BukkitPlayerSelectorAdapter.java

@@ -0,0 +1,36 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.command.generic.PlayerSelector;
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+
+import java.util.Collection;
+import java.util.Collections;
+
+public class BukkitPlayerSelectorAdapter implements PlayerSelector {
+    private final org.incendo.cloud.bukkit.data.SinglePlayerSelector bukkitSelector;
+
+    public BukkitPlayerSelectorAdapter(org.incendo.cloud.bukkit.data.SinglePlayerSelector bukkitSelector) {
+        this.bukkitSelector = bukkitSelector;
+    }
+
+    @Override
+    public boolean isSingle() {
+        return true;
+    }
+
+    @Override
+    public PlatformPlayer getSinglePlayer() {
+        return new BukkitPlayer(bukkitSelector.single());
+    }
+
+    @Override
+    public Collection<PlatformPlayer> getPlayers() {
+        return Collections.singletonList(new BukkitPlayer(bukkitSelector.single()));
+    }
+
+    @Override
+    public String inputString() {
+        return bukkitSelector.inputString();
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/sender/BukkitPlayerSelectorParser.java

@@ -0,0 +1,28 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.command.generic.AbstractPlayerSelectorParser;
+import me.caseload.knockbacksync.command.generic.PlayerSelector;
+import org.incendo.cloud.bukkit.parser.selector.SinglePlayerSelectorParser;
+import org.incendo.cloud.context.CommandContext;
+import org.incendo.cloud.parser.ParserDescriptor;
+
+import java.util.concurrent.CompletableFuture;
+
+public class BukkitPlayerSelectorParser<C> extends AbstractPlayerSelectorParser<C> {
+
+    @Override
+    public ParserDescriptor<C, PlayerSelector> descriptor() {
+        return createDescriptor();
+    }
+
+    @Override
+    protected ParserDescriptor<C, ?> getPlatformSpecificDescriptor() {
+        return SinglePlayerSelectorParser.singlePlayerSelectorParser();
+    }
+
+    @Override
+    protected CompletableFuture<PlayerSelector> adaptToCommonSelector(CommandContext<C> context, Object platformSpecificSelector) {
+        return CompletableFuture.completedFuture(new BukkitPlayerSelectorAdapter((org.incendo.cloud.bukkit.data.SinglePlayerSelector) platformSpecificSelector));
+    }
+
+}

bukkit/src/main/java/me/caseload/knockbacksync/sender/BukkitSenderFactory.java

@@ -0,0 +1,88 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.BukkitBase;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.ConsoleCommandSender;
+import org.bukkit.command.RemoteConsoleCommandSender;
+import org.bukkit.entity.Player;
+import org.bukkit.permissions.Permission;
+import org.bukkit.permissions.PermissionDefault;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.incendo.cloud.SenderMapper;
+
+import java.util.UUID;
+
+public class BukkitSenderFactory extends SenderFactory<BukkitBase, CommandSender> implements SenderMapper<CommandSender, Sender> {
+//    private final BukkitAudiences audiences;
+
+    public BukkitSenderFactory(BukkitBase kbSyncBukkitBase) {
+        super(kbSyncBukkitBase);
+//        this.audiences = BukkitAudiences.create(kbSyncBukkitBase.getLoader());
+    }
+
+    @Override
+    protected String getName(CommandSender sender) {
+        if (sender instanceof Player) {
+            return sender.getName();
+        }
+        return Sender.CONSOLE_NAME;
+    }
+
+    @Override
+    protected UUID getUniqueId(CommandSender sender) {
+        if (sender instanceof Player) {
+            return ((Player) sender).getUniqueId();
+        }
+        return Sender.CONSOLE_UUID;
+    }
+
+    @Override
+    protected void sendMessage(CommandSender sender, String message) {
+        sender.sendMessage(message);
+    }
+
+//    @Override
+//    protected void sendMessage(CommandSender sender, Component message) {
+//        // we can safely send async for players and the console - otherwise, send it sync
+//        if (sender instanceof Player || sender instanceof ConsoleCommandSender || sender instanceof RemoteConsoleCommandSender) {
+//            this.audiences.sender(sender).sendMessage(message);
+//        } else {
+//            getPlugin().getBootstrap().getScheduler().executeSync(() -> this.audiences.sender(sender).sendMessage(message));
+//        }
+//    }
+
+    @Override
+    protected boolean hasPermission(CommandSender sender, String node) {
+        return sender.hasPermission(node);
+    }
+
+    @Override
+    protected boolean hasPermission(CommandSender sender, String node, boolean defaultIfUnset) {
+        return sender.hasPermission(new Permission(node, defaultIfUnset ? PermissionDefault.TRUE : PermissionDefault.FALSE));
+    }
+
+    @Override
+    protected void performCommand(CommandSender sender, String command) {
+        //
+    }
+
+    @Override
+    protected boolean isConsole(CommandSender sender) {
+        return sender instanceof ConsoleCommandSender || sender instanceof RemoteConsoleCommandSender;
+    }
+
+    @Override
+    public @NonNull Sender map(@NonNull CommandSender base) {
+        return this.wrap(base);
+    }
+
+    @Override
+    public @NonNull CommandSender reverse(@NonNull Sender mapped) {
+        return this.unwrap(mapped);
+    }
+
+    @Override
+    public void close() throws Exception {
+
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/stats/custom/BukkitStatsManager.java

@@ -0,0 +1,11 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import me.caseload.knockbacksync.Base;
+import org.bukkit.plugin.Plugin;
+
+public class BukkitStatsManager extends StatsManager {
+
+    public BukkitStatsManager(Plugin plugin) {
+        super(new MetricsBukkit(plugin, 23568));
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/stats/custom/MetricsBukkit.java

@@ -0,0 +1,156 @@
+package me.caseload.knockbacksync.stats.custom;
+
+
+/*
+ * This Metrics class was auto-generated and can be copied into your project if you are
+ * not using a build tool like Gradle or Maven for dependency management.
+ *
+ * IMPORTANT: You are not allowed to modify this class, except changing the package.
+ *
+ * Disallowed modifications include but are not limited to:
+ *  - Remove the option for users to opt-out
+ *  - Change the frequency for data submission
+ *  - Obfuscate the code (every obfuscator should allow you to make an exception for specific files)
+ *  - Reformat the code (if you use a linter, add an exception)
+ *
+ * Violations will result in a ban of your plugin and account from bStats.
+ */
+
+import me.caseload.knockbacksync.BukkitLoaderPlugin;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.stats.CustomChart;
+import me.caseload.knockbacksync.stats.JsonObjectBuilder;
+import org.bukkit.Bukkit;
+import org.bukkit.configuration.file.YamlConfiguration;
+import org.bukkit.entity.Player;
+import org.bukkit.plugin.Plugin;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.Method;
+import java.util.Collection;
+import java.util.UUID;
+import java.util.logging.Level;
+
+public class MetricsBukkit implements Metrics {
+
+    private final Plugin plugin;
+    private final MetricsBase metricsBase;
+
+
+    public MetricsBukkit(Plugin plugin, int serviceId) {
+        this.plugin = plugin;
+        // Get the config file
+        File bStatsFolder = new File(plugin.getDataFolder().getParentFile(), "bStats");
+        File configFile = new File(bStatsFolder, "config.yml");
+        YamlConfiguration config = YamlConfiguration.loadConfiguration(configFile);
+        if (!config.isSet("serverUuid")) {
+            config.addDefault("enabled", true);
+            config.addDefault("serverUuid", UUID.randomUUID().toString());
+            config.addDefault("logFailedRequests", false);
+            config.addDefault("logSentData", false);
+            config.addDefault("logResponseStatusText", false);
+            // Inform the server owners about bStats
+            config
+                    .options()
+                    .header(
+                            "bStats (https://bStats.org) collects some basic information for plugin authors, like how\n"
+                                    + "many people use their plugin and their total player count. It's recommended to keep bStats\n"
+                                    + "enabled, but if you're not comfortable with this, you can turn this setting off. There is no\n"
+                                    + "performance penalty associated with having metrics enabled, and data sent to bStats is fully\n"
+                                    + "anonymous.")
+                    .copyDefaults(true);
+            try {
+                config.save(configFile);
+            } catch (IOException ignored) {
+            }
+        }
+        // Load the data
+        boolean enabled = config.getBoolean("enabled", true);
+        String serverUUID = config.getString("serverUuid");
+        boolean logErrors = config.getBoolean("logFailedRequests", false);
+        boolean logSentData = config.getBoolean("logSentData", false);
+        boolean logResponseStatusText = config.getBoolean("logResponseStatusText", false);
+//        boolean isFolia = false;
+//        try {
+//            isFolia = Class.forName("io.papermc.paper.threadedregions.RegionizedServer") != null;
+//        } catch (Exception e) {
+//        }
+        metricsBase =
+                new // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        // See https://github.com/Bastian/bstats-metrics/pull/126
+                        MetricsBase(
+                        "bukkit",
+                        serverUUID,
+                        serviceId,
+                        enabled,
+                        this::appendPlatformData,
+                        this::appendServiceData,
+                        submitDataTask -> Base.INSTANCE.getScheduler().runTask(submitDataTask),
+//                        isFolia
+//                                ? null
+//                                : submitDataTask -> Bukkit.getScheduler().runTask(plugin, submitDataTask),
+                        plugin::isEnabled,
+                        (message, error) -> this.plugin.getLogger().log(Level.WARNING, message, error),
+                        (message) -> this.plugin.getLogger().log(Level.INFO, message),
+                        logErrors,
+                        logSentData,
+                        logResponseStatusText,
+                        false);
+    }
+
+    /**
+     * Shuts down the underlying scheduler service.
+     */
+    @Override
+    public void shutdown() {
+        metricsBase.shutdown();
+    }
+
+    /**
+     * Adds a custom chart.
+     *
+     * @param chart The chart to add.
+     */
+    public void addCustomChart(CustomChart chart) {
+        metricsBase.addCustomChart(chart);
+    }
+
+    private void appendPlatformData(JsonObjectBuilder builder) {
+        builder.appendField("playerAmount", getPlayerAmount());
+        builder.appendField("onlineMode", Bukkit.getOnlineMode() ? 1 : 0);
+        builder.appendField("bukkitVersion", Bukkit.getVersion());
+        builder.appendField("bukkitName", Bukkit.getName());
+        builder.appendField("javaVersion", System.getProperty("java.version"));
+        builder.appendField("osName", System.getProperty("os.name"));
+        builder.appendField("osArch", System.getProperty("os.arch"));
+        builder.appendField("osVersion", System.getProperty("os.version"));
+        builder.appendField("coreCount", Runtime.getRuntime().availableProcessors());
+    }
+
+    private void appendServiceData(JsonObjectBuilder builder) {
+        builder.appendField("pluginVersion", plugin.getDescription().getVersion());
+    }
+
+    private int getPlayerAmount() {
+        try {
+            // Around MC 1.8 the return type was changed from an array to a collection,
+            // This fixes java.lang.NoSuchMethodError:
+            // org.bukkit.Bukkit.getOnlinePlayers()Ljava/util/Collection;
+            Method onlinePlayersMethod = Class.forName("org.bukkit.Server").getMethod("getOnlinePlayers");
+            return onlinePlayersMethod.getReturnType().equals(Collection.class)
+                    ? ((Collection<?>) onlinePlayersMethod.invoke(Bukkit.getServer())).size()
+                    : ((Player[]) onlinePlayersMethod.invoke(Bukkit.getServer())).length;
+        } catch (Exception e) {
+            // Just use the new method if the reflection failed
+            return Bukkit.getOnlinePlayers().size();
+        }
+    }
+}
+
+

bukkit/src/main/java/me/caseload/knockbacksync/util/MultiLibUtil.java

@@ -0,0 +1,32 @@
+package me.caseload.knockbacksync.util;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import org.bukkit.entity.Player;
+
+import java.lang.reflect.Method;
+
+public class MultiLibUtil {
+
+    public final static Method externalPlayerMethod = getMethod(Player.class, "isExternalPlayer");
+
+    public static Method getMethod(Class<?> clazz, String methodName) {
+        try {
+            return clazz.getMethod(methodName);
+        } catch (NoSuchMethodException e) {
+            return null;
+        }
+    }
+
+    // TODO: cache external players for better performance, but this only matters for people using multi-lib
+    public static boolean isExternalPlayer(Player player) {
+        if (externalPlayerMethod == null || (PacketEvents.getAPI().getServerManager().getVersion().isOlderThan(ServerVersion.V_1_18)))
+            return false;
+        try {
+            return (boolean) externalPlayerMethod.invoke(player);
+        } catch (Exception e) {
+            e.printStackTrace();
+            return false;
+        }
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/world/BukkitServer.java

@@ -0,0 +1,28 @@
+package me.caseload.knockbacksync.world;
+
+import me.caseload.knockbacksync.player.BukkitPlayer;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import org.bukkit.Bukkit;
+import org.bukkit.entity.Player;
+
+import java.util.Collection;
+import java.util.UUID;
+import java.util.stream.Collectors;
+
+public class BukkitServer implements PlatformServer {
+    public Collection<PlatformPlayer> getOnlinePlayers() {
+        return Bukkit.getOnlinePlayers().stream()
+                .map(BukkitPlayer::new)
+                .collect(Collectors.toList());
+    }
+
+    @Override
+    public PlatformPlayer getPlayer(UUID uuid) {
+        return new BukkitPlayer(Bukkit.getPlayer(uuid));
+    }
+
+    @Override
+    public PlatformPlayer getPlayer(Object nativePlatformPlayer) {
+        return new BukkitPlayer((Player) nativePlatformPlayer);
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/world/FoliaWorld.java

@@ -0,0 +1,18 @@
+package me.caseload.knockbacksync.world;
+
+import com.github.retrooper.packetevents.protocol.world.states.WrappedBlockState;
+import io.github.retrooper.packetevents.util.SpigotConversionUtil;
+import org.bukkit.World;
+import org.bukkit.block.BlockState;
+
+public class FoliaWorld extends SpigotWorld {
+    public FoliaWorld(World world) {
+        super(world);
+    }
+
+    @Override
+    public WrappedBlockState getBlockStateAt(int x, int y, int z) {
+        BlockState block = this.world.getBlockState(x, y, z);
+        return SpigotConversionUtil.fromBukkitBlockData(block.getBlockData());
+    }
+}

bukkit/src/main/java/me/caseload/knockbacksync/world/SpigotWorld.java

@@ -0,0 +1,169 @@
+package me.caseload.knockbacksync.world;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import com.github.retrooper.packetevents.protocol.world.BlockFace;
+import com.github.retrooper.packetevents.protocol.world.states.WrappedBlockState;
+import com.github.retrooper.packetevents.util.Vector3d;
+import com.github.retrooper.packetevents.util.Vector3i;
+import io.github.retrooper.packetevents.util.SpigotConversionUtil;
+import me.caseload.knockbacksync.world.raytrace.FluidHandling;
+import me.caseload.knockbacksync.world.raytrace.RayTraceResult;
+import org.bukkit.Bukkit;
+import org.bukkit.FluidCollisionMode;
+import org.bukkit.World;
+import org.bukkit.block.Block;
+import org.bukkit.util.Vector;
+
+import java.lang.reflect.Method;
+
+public class SpigotWorld implements PlatformWorld {
+    protected final World world;
+
+    // Reflection variables
+    private static Class<?> craftWorldClass;
+    private static Class<?> vec3DClass;
+    private static Class<?> movingObjectPositionClass;
+    private static Class<?> enumDirectionClass;
+    private static Method craftWorldGetHandleMethod;
+    private static Method rayTraceMethod;
+    private static Method vec3DAddMethod;
+
+    static {
+        if (PacketEvents.getAPI().getServerManager().getVersion().isOlderThan(ServerVersion.V_1_13)) {
+            try {
+                Object server = Bukkit.getServer().getClass().getDeclaredMethod("getServer").invoke(Bukkit.getServer());
+                String nmsPackage = server.getClass().getPackage().getName();
+                String bukkitPackage = Bukkit.getServer().getClass().getPackage().getName();
+
+                // Load necessary classes dynamically for Minecraft 1.12.2
+                craftWorldClass = Class.forName(bukkitPackage + ".CraftWorld");
+                vec3DClass = Class.forName(nmsPackage + ".Vec3D");
+                movingObjectPositionClass = Class.forName(nmsPackage + ".MovingObjectPosition");
+                enumDirectionClass = Class.forName(nmsPackage + ".EnumDirection");
+
+//                CraftWorld
+
+                // Get method
+                craftWorldGetHandleMethod = craftWorldClass.getMethod("getHandle");
+                rayTraceMethod = Class.forName(nmsPackage + ".World").getMethod("rayTrace", vec3DClass, vec3DClass, boolean.class, boolean.class, boolean.class);
+                vec3DAddMethod = vec3DClass.getMethod("add", double.class, double.class, double.class);
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    public SpigotWorld(World world) {
+        this.world = world;
+    }
+
+    private static BlockFace getBlockFaceFrom(org.bukkit.block.BlockFace direction) {
+        switch (direction) {
+            case NORTH:
+                return BlockFace.NORTH;
+            case SOUTH:
+                return BlockFace.SOUTH;
+            case EAST:
+                return BlockFace.EAST;
+            case WEST:
+                return BlockFace.WEST;
+            case UP:
+                return BlockFace.UP;
+            case DOWN:
+                return BlockFace.DOWN;
+            default:
+                return null;
+        }
+    }
+
+    @Override
+    public WrappedBlockState getBlockStateAt(int x, int y, int z) {
+        Block block = world.getBlockAt(x, y, z);
+        return SpigotConversionUtil.fromBukkitBlockData(block.getBlockData());
+    }
+
+    @Override
+    public WrappedBlockState getBlockStateAt(Vector3d loc) {
+        return getBlockStateAt((int) Math.floor(loc.x), (int) Math.floor(loc.y), (int) Math.floor(loc.z));
+    }
+
+    @Override
+    public RayTraceResult rayTraceBlocks(Vector3d start, Vector3d direction, double maxDistance, FluidHandling fluidHandling, boolean ignorePassableBlocks) {
+        if (PacketEvents.getAPI().getServerManager().getVersion().isNewerThan(ServerVersion.V_1_12_2)) {
+            Vector startVec = new Vector(start.getX(), start.getY(), start.getZ());
+            Vector directionVec = new Vector(direction.getX(), direction.getY(), direction.getZ());
+
+            FluidCollisionMode fluidMode = (fluidHandling == FluidHandling.NONE) ? FluidCollisionMode.NEVER :
+                    (fluidHandling == FluidHandling.SOURCE_ONLY) ? FluidCollisionMode.SOURCE_ONLY :
+                            FluidCollisionMode.ALWAYS;
+
+            org.bukkit.util.RayTraceResult result = world.rayTraceBlocks(startVec.toLocation(world), directionVec, maxDistance, fluidMode, ignorePassableBlocks);
+
+            if (result == null) return null;
+
+            return new RayTraceResult(
+                    new Vector3d(result.getHitPosition().getX(), result.getHitPosition().getY(), result.getHitPosition().getZ()),
+                    getBlockFaceFrom(result.getHitBlockFace()),
+                    new Vector3i(result.getHitBlock().getX(), result.getHitBlock().getY(), result.getHitBlock().getZ()),
+                    result.getHitBlock() != null ? SpigotConversionUtil.fromBukkitBlockData(result.getHitBlock().getBlockData()) : null
+            );
+            // Only tested on 1.12.2
+        } else {
+            try {
+                // Create start and end positions
+                Object startPos = vec3DClass.getConstructor(double.class, double.class, double.class)
+                        .newInstance(start.getX(), start.getY(), start.getZ());
+                Object endPos = vec3DAddMethod.invoke(startPos, direction.getX(), direction.getY(), direction.getZ());
+
+                // Call rayTrace method
+                Object hitResult = rayTraceMethod.invoke(craftWorldGetHandleMethod.invoke(world), startPos, endPos, false, true, false);
+                if (hitResult == null) return null;
+
+                // Extract hit position and direction
+                Vector3d hitPosition = new Vector3d(
+                        (double) hitResult.getClass().getField("pos").get(hitResult),
+                        (double) hitResult.getClass().getField("pos").get(hitResult).getClass().getField("y").get(hitResult.getClass().getField("pos").get(hitResult)),
+                        (double) hitResult.getClass().getField("pos").get(hitResult).getClass().getField("z").get(hitResult.getClass().getField("pos").get(hitResult))
+                );
+
+                Object hitDirection = hitResult.getClass().getField("direction").get(hitResult);
+                Object hitBlock = hitResult.getClass().getField("e").get(hitResult); // e = BlockHitResult
+
+                return new RayTraceResult(
+                        hitPosition,
+                        getHitBlockFace(hitDirection),
+                        new Vector3i((int) hitBlock.getClass().getField("x").get(hitBlock),
+                                (int) hitBlock.getClass().getField("y").get(hitBlock),
+                                (int) hitBlock.getClass().getField("z").get(hitBlock)),
+                        hitBlock != null ? WrappedBlockState.getByString(hitBlock.getClass().getField("type").get(hitBlock).toString()) : null
+                );
+            } catch (Exception e) {
+                e.printStackTrace();
+                return null; // Return null if there was an error during ray tracing
+            }
+        }
+    }
+
+    private static BlockFace getHitBlockFace(Object enumDirection) {
+        try {
+            // Match the EnumDirection to the corresponding BlockFace
+            if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("NORTH").get(null))) {
+                return BlockFace.NORTH;
+            } else if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("SOUTH").get(null))) {
+                return BlockFace.SOUTH;
+            } else if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("EAST").get(null))) {
+                return BlockFace.EAST;
+            } else if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("WEST").get(null))) {
+                return BlockFace.WEST;
+            } else if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("UP").get(null))) {
+                return BlockFace.UP;
+            } else if (enumDirection.equals(SpigotWorld.enumDirectionClass.getField("DOWN").get(null))) {
+                return BlockFace.DOWN;
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        throw new IllegalStateException("Unexpected value: " + enumDirection);
+    }
+}

bukkit/src/main/resources/plugin.yml

@@ -0,0 +1,23 @@
+name: KnockbackSync-OG
+version: ${version}
+main: me.caseload.knockbacksync.BukkitLoaderPlugin
+api-version: '1.13' # We actually support 1.12.2, api-version was added later though
+authors: [ Caseload, Axionize ]
+description: Synchronizes player knockback for smoother gameplay.
+folia-supported: true
+depend: ${depend}
+permissions:
+  knockbacksync.update:
+    default: op
+  knockbacksync.toggle.global:
+    default: op
+  knockbacksync.toggle.other:
+    default: op
+  knockbacksync.toggle.self:
+    default: op
+  knockbacksync.ping:
+    default: op
+  knockbacksync.reload:
+    default: op
+  knockbacksync.toggleoffground:
+    default: op

common/build.gradle.kts

@@ -0,0 +1,35 @@
+plugins {
+    id("com.github.gmazzo.buildconfig") version "3.1.0"
+}
+
+val shadePE: Boolean by rootProject.extra
+
+dependencies {
+    // True compileOnly deps
+    compileOnly("org.geysermc.floodgate:api:2.0-SNAPSHOT")
+    compileOnly("io.netty:netty-all:4.1.72.Final")
+    compileOnly("org.projectlombok:lombok:1.18.34")
+    annotationProcessor("org.projectlombok:lombok:1.18.34")
+
+    // Upstream 2.11.2 API; runtime impl is the externally installed True-OG fork or the shaded bundle.
+    if (shadePE) {
+        implementation("com.github.retrooper:packetevents-api:2.11.2")
+    } else {
+        compileOnly("com.github.retrooper:packetevents-api:2.11.2")
+    }
+
+    implementation("org.yaml:snakeyaml:2.0")
+    implementation("org.kohsuke:github-api:1.326") {
+        exclude(group = "commons-io", module = "commons-io")
+        exclude(group = "org.apache.commons", module = "commons-lang3")
+    }
+
+    implementation("org.incendo:cloud-core:2.0.0")
+    implementation("org.incendo:cloud-minecraft-extras:2.0.0-beta.10")
+}
+
+buildConfig {
+    buildConfigField("String", "GITHUB_REPO", "\"${project.rootProject.ext["githubRepo"]}\"")
+    // Exposes shadePE to source code as a compile-time constant.
+    buildConfigField("boolean", "SHADE_PE", shadePE.toString())
+}

common/src/main/java/me/caseload/knockbacksync/Base.java

@@ -0,0 +1,319 @@
+package me.caseload.knockbacksync;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.event.PacketListenerCommon;
+import lombok.Getter;
+import me.caseload.knockbacksync.command.MainCommand;
+import me.caseload.knockbacksync.common.BuildConfig;
+import me.caseload.knockbacksync.command.generic.AbstractPlayerSelectorParser;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.command.subcommand.PingCommand;
+import me.caseload.knockbacksync.command.subcommand.ReloadCommand;
+import me.caseload.knockbacksync.command.subcommand.StatusCommand;
+import me.caseload.knockbacksync.command.subcommand.ToggleCommand;
+import me.caseload.knockbacksync.command.subcommand.ToggleOffGroundSubcommand;
+import me.caseload.knockbacksync.event.Event;
+import me.caseload.knockbacksync.event.EventBus;
+import me.caseload.knockbacksync.event.OptimizedEventBus;
+import me.caseload.knockbacksync.listener.packetevents.*;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.permission.PermissionChecker;
+import me.caseload.knockbacksync.scheduler.SchedulerAdapter;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.stats.custom.ClientBrandsPie;
+import me.caseload.knockbacksync.stats.custom.PluginJarHashProvider;
+import me.caseload.knockbacksync.stats.custom.StatsManager;
+import me.caseload.knockbacksync.world.PlatformServer;
+import org.incendo.cloud.CommandManager;
+import org.kohsuke.github.GitHub;
+
+import java.io.DataInputStream;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.InputStream;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.net.URLDecoder;
+import java.nio.file.Paths;
+import java.util.*;
+import java.util.logging.Logger;
+
+// Base class
+public abstract class Base {
+    public static Logger LOGGER;
+    public static Base INSTANCE;
+
+    @Getter private final Platform platform;
+    @Getter protected StatsManager statsManager;
+    @Getter protected PlatformServer platformServer;
+    @Getter protected PluginJarHashProvider pluginJarHashProvider;
+    @Getter protected SchedulerAdapter scheduler;
+    @Getter protected ConfigManager configManager;
+    @Getter protected CommandManager<Sender> commandManager;
+    @Getter protected final EventBus eventBus = new OptimizedEventBus();
+
+    @Getter
+    protected AbstractPlayerSelectorParser<Sender> playerSelectorParser;
+
+    // Tracked so onDisable can unregister exactly the listeners registered against the shared provider.
+    private final java.util.List<PacketListenerCommon> peListenerHandles = new java.util.ArrayList<>();
+
+    protected Base() {
+        this.platform = detectPlatform();
+        INSTANCE = this;
+    }
+
+    private Platform detectPlatform() {
+        final Map<String, Platform> platforms = Collections.unmodifiableMap(new HashMap<String, Platform>() {{
+            put("io.papermc.paper.threadedregions.RegionizedServer", Platform.FOLIA);
+            put("org.bukkit.Bukkit", Platform.BUKKIT);
+            put("net.fabricmc.loader.api.FabricLoader", Platform.FABRIC);
+        }});
+
+        return platforms.entrySet().stream()
+                .filter(entry -> isClassPresent(entry.getKey()))
+                .map(Map.Entry::getValue)
+                .findFirst()
+                .orElseThrow(() -> new IllegalStateException("Unknown platform!"));
+    }
+
+    private boolean isClassPresent(String className) {
+        try {
+            Class.forName(className);
+            return true;
+        } catch (ClassNotFoundException ignored) {
+            return false;
+        }
+    }
+
+    public abstract Logger getLogger();
+
+    public abstract File getDataFolder();
+
+    public abstract InputStream getResource(String filename);
+
+    public abstract void load();
+
+    public void enable() {
+        LOGGER = getLogger();
+        saveDefaultConfig();
+        initializePacketEvents();
+        registerCommonListeners();
+        registerPlatformListeners();
+        registerCommands();
+        initializeScheduler();
+        configManager.loadConfig(false);
+        statsManager.init();
+        checkForUpdates();
+    }
+
+    public abstract void initializeScheduler();
+
+    public void initializePacketEvents() {
+        // External-provider mode skips lifecycle ownership entirely.
+        if (!BuildConfig.SHADE_PE) {
+            return;
+        }
+        PacketEvents.getAPI().getSettings()
+                .checkForUpdates(false)
+                .debug(false);
+
+        PacketEvents.getAPI().init();
+    }
+
+    protected void registerCommonListeners() {
+        registerTrackedPacketListener(new AttributeChangeListener());
+        registerTrackedPacketListener(new PingSendListener());
+        registerTrackedPacketListener(new PingReceiveListener());
+        registerTrackedPacketListener(new PacketPlayerJoinQuit());
+        registerTrackedPacketListener(new ClientBrandListener());
+        Event.setEventBus(eventBus);
+    }
+
+    /** Register a PacketEvents listener and remember its handle for unregister on disable. */
+    protected void registerTrackedPacketListener(PacketListenerCommon listener) {
+        PacketEvents.getAPI().getEventManager().registerListener(listener);
+        peListenerHandles.add(listener);
+    }
+
+    /** Unregister every tracked PacketEvents listener. */
+    public void unregisterPacketListeners() {
+        for (PacketListenerCommon handle : peListenerHandles) {
+            try {
+                PacketEvents.getAPI().getEventManager().unregisterListener(handle);
+            } catch (Throwable t) {
+                if (LOGGER != null) {
+                    LOGGER.warning("Failed to unregister PE listener: " + t.getMessage());
+                }
+            }
+        }
+        peListenerHandles.clear();
+    }
+
+    protected abstract void registerPlatformListeners();
+
+    protected void registerCommands() {
+        List<BuilderCommand> list = Arrays.asList(
+                new MainCommand(),
+                new ReloadCommand(),
+                new PingCommand(),
+                new StatusCommand(),
+                new ToggleOffGroundSubcommand(),
+                new ToggleCommand()
+        );
+        list.forEach(command -> command.register(commandManager));
+    }
+
+    protected abstract String getVersion();
+
+    protected void checkForUpdates() {
+        getLogger().info("Checking for updates...");
+
+        scheduler.runTaskAsynchronously(() -> {
+            try {
+                GitHub github = GitHub.connectAnonymously();
+                String latestVersion = github.getRepository("CASELOAD7000/knockback-sync")
+                        .getLatestRelease()
+                        .getTagName();
+
+                String currentVersion = getVersion();
+
+                int comparisonResult = compareVersions(currentVersion, latestVersion);
+
+                if (comparisonResult < 0) {
+                    LOGGER.warning("You are running an older version. A new update is available for download at: https://github.com/CASELOAD7000/knockback-sync/releases/latest");
+                    configManager.setUpdateAvailable(true);
+                } else if (comparisonResult > 0) {
+                    if (currentVersion.contains("-dev")) 
+                        LOGGER.info("You are running a development build newer than the latest release.");
+                    else {
+                        LOGGER.info("You are running a version newer than the latest release.");
+                    }
+                } else {
+                    LOGGER.info("You are running the latest release.");
+                }
+
+                if (configManager.isUpdateAvailable() && configManager.isAutoUpdate()) {
+                    LOGGER.info("Updating...");
+                    byte[] bytes = downloadLatestRelease(github);
+                    updatePlugin(bytes);
+
+                    if (hasRestartScript())
+                        scheduler.runTask(this::restartServer);
+                    else {
+                        // Yeah
+                    }
+                }
+            } catch (Exception e) {
+                LOGGER.severe("Failed to check for updates: " + e.getMessage());
+            }
+        });
+    }
+
+    private void updatePlugin(byte[] pluginBytes) throws URISyntaxException {
+        File file = new File(getJarURL().toURI());
+
+        try (FileOutputStream outputStream = new FileOutputStream(file)) {
+            outputStream.write(pluginBytes);
+            LOGGER.info("Successfully updated the plugin!");
+        } catch (Exception e) {
+            LOGGER.severe("Failed to update: " + e.getMessage());
+        }
+    }
+
+    private byte[] downloadLatestRelease(GitHub github) {
+        try {
+            return github.getRepository("CASELOAD7000/knockback-sync")
+                    .getLatestRelease()
+                    .getAssets().stream()
+                    .filter(asset -> asset.getName().endsWith(".jar")
+                            && asset.getName().contains(platform.equals(Platform.FABRIC)
+                            ? "fabric" : "bukkit"))
+                    .findFirst()
+                    .map(asset -> {
+                        try (InputStream inputStream = new URL(asset.getBrowserDownloadUrl()).openStream()) {
+                            inputStream.reset();
+                            byte[] bytes = new byte[inputStream.available()];
+                            DataInputStream dataInputStream = new DataInputStream(inputStream);
+                            dataInputStream.readFully(bytes);
+                            return bytes;
+                        } catch (Exception e) {
+                            LOGGER.severe("Failed to download latest release: " + e.getMessage());
+                            return null;
+                        }
+                    }).orElse(null);
+        } catch (Exception e) {
+            LOGGER.severe("Failed to locate latest release: " + e.getMessage());
+            return null;
+        }
+    }
+
+    private int compareVersions(String version1, String version2) {
+        String[] v1Parts = version1.split("[-.]");
+        String[] v2Parts = version2.split("[-.]");
+
+        int length = Math.min(v1Parts.length, v2Parts.length);
+
+        for (int i = 0; i < length; i++) {
+            int comparison = compareVersionPart(v1Parts[i], v2Parts[i]);
+            if (comparison != 0) {
+                return comparison;
+            }
+        }
+
+        // If we're here, all compared parts are equal
+        if (v1Parts.length != v2Parts.length) {
+            return compareSpecialVersions(v1Parts, v2Parts);
+        }
+
+        return 0; // Versions are equal
+    }
+
+    private int compareVersionPart(String part1, String part2) {
+        try {
+            int v1 = Integer.parseInt(part1);
+            int v2 = Integer.parseInt(part2);
+            return Integer.compare(v1, v2);
+        } catch (NumberFormatException e) {
+            // If parts are not numbers, compare them based on dev < snapshot < release
+            return compareSpecialPart(part1, part2);
+        }
+    }
+
+    private int compareSpecialPart(String part1, String part2) {
+        if (part1.equals(part2)) return 0;
+        if (part1.startsWith("dev")) return part2.startsWith("dev") ? 0 : -1;
+        if (part2.startsWith("dev")) return 1;
+        if (part1.equals("SNAPSHOT")) return part2.equals("SNAPSHOT") ? 0 : -1;
+        if (part2.equals("SNAPSHOT")) return 1;
+        return part1.compareTo(part2);
+    }
+
+    private int compareSpecialVersions(String[] v1Parts, String[] v2Parts) {
+        if (v1Parts.length > v2Parts.length) {
+            String specialPart = v1Parts[v2Parts.length];
+            if (specialPart.startsWith("dev")) return -1;
+            if (specialPart.equals("SNAPSHOT")) return -1;
+            return 1; // Assume it's a release version part
+        } else {
+            String specialPart = v2Parts[v1Parts.length];
+            if (specialPart.startsWith("dev")) return 1;
+            if (specialPart.equals("SNAPSHOT")) return 1;
+            return -1; // Assume it's a release version part
+        }
+    }
+
+    public abstract void saveDefaultConfig();
+
+    public abstract PermissionChecker getPermissionChecker();
+
+    public abstract float getTickRate();
+
+    public abstract URL getJarURL();
+
+    public abstract void restartServer();
+
+    public abstract boolean hasRestartScript();
+}
+
+

common/src/main/java/me/caseload/knockbacksync/ConfigWrapper.java

@@ -0,0 +1,95 @@
+package me.caseload.knockbacksync;
+
+import me.caseload.knockbacksync.util.NumberConversions;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+public class ConfigWrapper {
+    private final Map<String, Object> configMap;
+
+    public ConfigWrapper(Map<String, Object> configMap) {
+        this.configMap = configMap;
+    }
+
+    public String getString(String path, String def) {
+        Object value = getValue(path);
+        return value instanceof String ? (String) value : def;
+    }
+
+    public boolean getBoolean(String path, boolean def) {
+        Object value = getValue(path);
+        return value instanceof Boolean ? (Boolean) value : def;
+    }
+
+    public int getInt(String path, int def) {
+        Object value = getValue(path);
+        return NumberConversions.toInt(value, def);
+    }
+
+    public long getLong(String path, long def) {
+        Object value = getValue(path);
+        return NumberConversions.toLong(value, def);
+    }
+
+    public double getDouble(String path, double def) {
+        Object value = getValue(path);
+        if (value instanceof Number) return ((Number) value).doubleValue();
+        if (value instanceof String) {
+            try {
+                return Double.parseDouble((String) value);
+            } catch (NumberFormatException ignored) {
+                return def;
+            }
+        }
+        return def;
+    }
+
+    public void set(String path, Object value) {
+        setValue(path, value);
+    }
+
+    private Object getValue(String path) {
+        String[] parts = path.split("\\.");
+        Object current = configMap;
+        for (String part : parts) {
+            if (current instanceof Map) {
+                current = ((Map<?, ?>) current).get(part);
+            } else {
+                return null; // Path not found
+            }
+        }
+        return current;
+    }
+
+    private void setValue(String path, Object value) {
+        String[] parts = path.split("\\.");
+        Map<String, Object> current = configMap;
+        for (int i = 0; i < parts.length - 1; i++) {
+            String part = parts[i];
+            if (!current.containsKey(part) || !(current.get(part) instanceof Map)) {
+                current.put(part, new HashMap<>());
+            }
+            current = (Map<String, Object>) current.get(part);
+        }
+        current.put(parts[parts.length - 1], value);
+    }
+
+    public boolean contains(String path) {
+        return getValue(path) != null;
+    }
+
+    public Object get(String path) {
+        return getValue(path);
+    }
+
+    public Set<String> getKeys(String path) {
+        Object value = getValue(path);
+        if (value instanceof Map) {
+            return ((Map<String, Object>) value).keySet();
+        }
+        return new HashSet<>();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/Platform.java

@@ -0,0 +1,7 @@
+package me.caseload.knockbacksync;
+
+public enum Platform {
+    FABRIC,
+    BUKKIT,
+    FOLIA
+}

common/src/main/java/me/caseload/knockbacksync/command/MainCommand.java

@@ -0,0 +1,22 @@
+package me.caseload.knockbacksync.command;
+
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+
+public class MainCommand implements BuilderCommand {
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+                manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                        .handler(context -> {
+                            context.sender().sendMessage(
+                                    ChatUtil.translateAlternateColorCodes(
+                                            '&',
+                                            "&6This server is running the &eKnockbackSync &6plugin. &bhttps://github.com/CASELOAD7000/knockback-sync"
+                                    )
+                            );
+                        })
+        );
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/generic/AbstractPlayerSelectorParser.java

@@ -0,0 +1,23 @@
+package me.caseload.knockbacksync.command.generic;
+
+import org.incendo.cloud.context.CommandContext;
+import org.incendo.cloud.parser.ParserDescriptor;
+
+import java.util.concurrent.CompletableFuture;
+
+public abstract class AbstractPlayerSelectorParser<C> {
+
+    public abstract ParserDescriptor<C, PlayerSelector> descriptor();
+
+    protected abstract ParserDescriptor<C, ?> getPlatformSpecificDescriptor();
+
+    protected abstract CompletableFuture<PlayerSelector> adaptToCommonSelector(CommandContext<C> context, Object platformSpecificSelector);
+
+    // Helper method to create the ParserDescriptor
+    protected ParserDescriptor<C, PlayerSelector> createDescriptor() {
+        return ParserDescriptor.of(
+                getPlatformSpecificDescriptor().parser().mapSuccess(this::adaptToCommonSelector),
+                PlayerSelector.class
+        );
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/generic/BuilderCommand.java

@@ -0,0 +1,9 @@
+package me.caseload.knockbacksync.command.generic;
+
+import me.caseload.knockbacksync.sender.Sender;
+import org.incendo.cloud.CommandManager;
+
+public interface BuilderCommand {
+
+    void register(CommandManager<Sender> manager);
+}

common/src/main/java/me/caseload/knockbacksync/command/generic/PlayerSelector.java

@@ -0,0 +1,15 @@
+package me.caseload.knockbacksync.command.generic;
+
+import me.caseload.knockbacksync.player.PlatformPlayer;
+
+import java.util.Collection;
+
+public interface PlayerSelector {
+    boolean isSingle();
+
+    PlatformPlayer getSinglePlayer(); // Throws an exception if not a single selection
+
+    Collection<PlatformPlayer> getPlayers();
+
+    String inputString();
+}

common/src/main/java/me/caseload/knockbacksync/command/subcommand/PingCommand.java

@@ -0,0 +1,129 @@
+package me.caseload.knockbacksync.command.subcommand;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.ConfigWrapper;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.command.generic.PlayerSelector;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+import org.incendo.cloud.permission.PredicatePermission;
+
+import java.util.UUID;
+import java.util.function.Predicate;
+
+public class PingCommand implements BuilderCommand {
+
+    private static final ConfigManager configManager = Base.INSTANCE.getConfigManager();
+
+    private String pingSelfAvailableMessage;
+    private String pingSelfUnavailableMessage;
+    private String pingOtherAvailableMessage;
+    private String pingOtherUnavailableMessage;
+
+    private String mustSpecifyPlayerFromConsoleMessage;
+    private String knockbacksyncDisabledForYouMessage;
+    private String knockbacksyncDisabledForTargetMessage;
+
+    public PingCommand() {
+        loadConfig();
+    }
+
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+            manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                .permission((sender -> {
+                    final String permission = "knockbacksync.ping";
+                    Predicate<Sender> senderPredicate = (s) -> {
+                        return s.hasPermission(permission, true);
+                    };
+
+                    return PredicatePermission.of(senderPredicate).testPermission(sender);
+                }))
+                .literal("ping")
+                .optional("target", Base.INSTANCE.getPlayerSelectorParser().descriptor())
+                .handler(context -> {
+                    PlayerSelector targetSelector = context.getOrDefault("target", null);
+
+                    if (targetSelector == null) {
+                        if (context.sender().isConsole()) {
+                            context.sender().sendMessage(ChatUtil.translateAlternateColorCodes('&', mustSpecifyPlayerFromConsoleMessage));
+                        } else {
+                            context.sender().sendMessage(getPingMessage(context.sender().getUniqueId(), context.sender().getName(), null, null));
+                        }
+                    } else {
+                        context.sender().sendMessage(getPingMessage(context.sender().getUniqueId(), context.sender().getName(), targetSelector.getSinglePlayer().getUUID(), targetSelector.getSinglePlayer().getName()));
+                    }
+                })
+        );
+        Base.INSTANCE.getEventBus().registerListeners(this);
+    }
+    private void loadConfig() {
+        ConfigWrapper configWrapper = configManager.getConfigWrapper();
+        pingSelfAvailableMessage = configWrapper.getString("messages.ping.self.available",
+                "Your real ping is &b%ping%&rms. Jitter: &b%jitter%&rms. Spike: &b%spike%&r. Compensated ping: &b%compensated%&rms.");
+        pingSelfUnavailableMessage = configWrapper.getString("messages.ping.self.unavailable",
+                "Accurate ping unavailable. Your estimated ping is &b%ping%&rms.");
+        pingOtherAvailableMessage = configWrapper.getString("messages.ping.other.available",
+                "%player%'s real ping is &b%ping%&rms. Jitter: &b%jitter%&rms. Spike: &b%spike%&r. Compensated ping: &b%compensated%&rms.");
+        pingOtherUnavailableMessage = configWrapper.getString("messages.ping.other.unavailable",
+                "Accurate ping unavailable. %player%'s estimated ping is &b%ping%&rms.");
+        mustSpecifyPlayerFromConsoleMessage = configWrapper.getString("messages.console.must_specify_player",
+                "&cYou must specify a player to use the knockbacksync ping command from the console.");
+        knockbacksyncDisabledForYouMessage = configWrapper.getString("messages.disabled.self",
+                "&cKnockback synchronization is currently disabled for you!");
+        knockbacksyncDisabledForTargetMessage = configWrapper.getString("messages.disabled.target",
+                "&cKnockback synchronization is currently disabled for the target player.");
+    }
+
+    private String getPingMessage(UUID senderUUID, String senderName, UUID targetUUID, String targetName) {
+        boolean isSelf = senderUUID.equals(targetUUID) || targetUUID == null;
+        String message;
+        if (isSelf) {
+            message = knockbacksyncDisabledForYouMessage;
+            targetUUID = senderUUID;
+            targetName = senderName;
+        } else {
+            message = knockbacksyncDisabledForTargetMessage;
+        }
+
+        User targetUser = Base.INSTANCE.getPlatformServer().getPlayer(targetUUID).getUser();
+        if (targetUser == null)
+            return ChatUtil.translateAlternateColorCodes('&',
+                    configManager.getPlayerDisconnectedWhileExecutingCommand()
+            ).replace("%player%", targetName);
+
+        PlayerData playerData = PlayerDataManager.getPlayerData(targetUser);
+        if (playerData == null)
+            return ChatUtil.translateAlternateColorCodes('&', message);
+
+        String rawReturnString;
+        if (playerData.getPing() == null) {
+            rawReturnString = isSelf ? pingSelfUnavailableMessage : pingOtherUnavailableMessage;
+        } else {
+            rawReturnString = isSelf ? pingSelfAvailableMessage : pingOtherAvailableMessage;
+        }
+
+        rawReturnString = rawReturnString
+                .replace("%player%", playerData.getPlatformPlayer().getName())
+                .replace("%ping%", playerData.getPing() == null ?
+                        String.valueOf(playerData.getPlatformPlayer().getPing()) :
+                        String.format("%.3f", playerData.getPing()))
+                .replace("%jitter%", String.format("%.3f", playerData.getJitter()))
+                .replace("%spike%", String.valueOf(playerData.isSpike()))
+                .replace("%compensated%", String.format("%.3f", playerData.getCompensatedPing()));
+
+        return ChatUtil.translateAlternateColorCodes('&', rawReturnString);
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReload(ConfigReloadEvent event) {
+        loadConfig();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/subcommand/ReloadCommand.java

@@ -0,0 +1,50 @@
+package me.caseload.knockbacksync.command.subcommand;
+
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+import org.incendo.cloud.permission.PredicatePermission;
+
+import java.util.function.Predicate;
+
+public class ReloadCommand implements BuilderCommand {
+
+    private static final ConfigManager configManager = Base.INSTANCE.getConfigManager();
+    private String rawReloadMessage = configManager.getConfigWrapper().getString("messages.reload.success", "&aSuccessfully reloaded KnockbackSync.");
+
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+            manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                    .literal("reload")
+                    .permission((sender -> {
+                        final String permission = "knockbacksync.reload";
+                        Predicate<Sender> senderPredicate = (s) -> {
+                            return s.hasPermission(permission, false);
+                        };
+
+                            return PredicatePermission.of(senderPredicate).testPermission(sender);
+                        }))
+                        .handler(context -> {
+                            configManager.loadConfig(true);
+
+                            // Fire the ConfigReloadEvent
+                            new ConfigReloadEvent(configManager).post();
+
+                            String reloadMessage = ChatUtil.translateAlternateColorCodes('&', rawReloadMessage);
+
+                            context.sender().sendMessage(reloadMessage);
+                        })
+        );
+        Base.INSTANCE.getEventBus().registerListeners(this);
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReload(ConfigReloadEvent event) {
+        rawReloadMessage = event.getConfigManager().getConfigWrapper().getString("messages.reload.success", "&aSuccessfully reloaded KnockbackSync.");
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/subcommand/StatusCommand.java

@@ -0,0 +1,132 @@
+package me.caseload.knockbacksync.command.subcommand;
+
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.ConfigWrapper;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.command.generic.PlayerSelector;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+import org.incendo.cloud.permission.PredicatePermission;
+
+import java.util.function.Predicate;
+
+public class StatusCommand implements BuilderCommand {
+
+    private static final ConfigManager configManager = Base.INSTANCE.getConfigManager();
+    private static final String STATUS_SELF_PERMISSION = "knockbacksync.status.self";
+    private static final String STATUS_OTHER_PERMISSION = "knockbacksync.status.other";
+
+    private String globalStatusEnabledMessage;
+    private String globalStatusDisabledMessage;
+    private String globalOffGroundStatusEnabledMessage;
+    private String globalOffGroundStatusDisabledMessage;
+    private String playerStatusEnabledMessage;
+    private String playerStatusDisabledMessage;
+    private String playerStatusGlobalDisabledMessage;
+    private String noSelfPermissionMessage;
+    private String noOtherPermissionMessage;
+
+    public StatusCommand() {
+        updateConfigValues();
+    }
+
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+                manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                        .literal("status")
+                        .optional("target", Base.INSTANCE.getPlayerSelectorParser().descriptor())
+                        .permission((sender -> {
+                            Predicate<Sender> senderPredicate = (s) -> {
+                                return s.hasPermission(STATUS_SELF_PERMISSION, true) || sender.hasPermission(STATUS_OTHER_PERMISSION, false);
+                            };
+
+                            return PredicatePermission.of(senderPredicate).testPermission(sender);
+                        }))
+                        .handler(context -> {
+                            Sender sender = context.sender();
+                            PlayerSelector targetSelector = context.getOrDefault("target", null);
+                            if (targetSelector == null) {
+                                // Show global status
+                                boolean globalStatus = configManager.isToggled();
+                                sender.sendMessage(
+                                        ChatUtil.translateAlternateColorCodes('&',
+                                                (globalStatus ? globalStatusEnabledMessage : globalStatusDisabledMessage))
+                                        + "\n"
+                                        + ChatUtil.translateAlternateColorCodes('&',
+                                                ToggleOffGroundSubcommand.offGroundSyncEnabled ? globalOffGroundStatusEnabledMessage : globalOffGroundStatusDisabledMessage)
+                                );
+
+                                    if (sender.hasPermission(STATUS_SELF_PERMISSION, true)) {
+                                        // Show player status for the sender (no target specified)
+                                        if (!sender.isConsole()) {
+                                            showPlayerStatus(sender, Base.INSTANCE.getPlatformServer().getPlayer(sender.getUniqueId()));
+                                        }
+                                    } else {
+                                        sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', noSelfPermissionMessage));
+                                    }
+                            } else {
+                                if (sender.hasPermission(STATUS_OTHER_PERMISSION, true)) {
+                                    PlatformPlayer target = targetSelector.getSinglePlayer();
+                                    showPlayerStatus(sender, target);
+                                } else {
+                                    sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', noOtherPermissionMessage));
+                                }
+                            }
+                        })
+        );
+        Base.INSTANCE.getEventBus().registerListeners(this);
+    }
+
+    private void showPlayerStatus(Sender sender, PlatformPlayer target) {
+        if (target.getUser() == null) {
+            String message = ChatUtil.translateAlternateColorCodes('&',
+                    configManager.getPlayerDisconnectedWhileExecutingCommand()
+            ).replace("%player%", target.getName());
+            sender.sendMessage(message);
+        }
+
+        boolean globalStatus = configManager.isToggled();
+        boolean playerStatus = PlayerDataManager.containsPlayerData(target.getUser());
+
+        String statusMessage;
+        if (!globalStatus) {
+            statusMessage = playerStatusGlobalDisabledMessage.replace("%player%", target.getName());
+        } else {
+           statusMessage = (playerStatus ? this.playerStatusEnabledMessage : this.playerStatusDisabledMessage).replace("%player%", target.getName());
+        }
+        sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', statusMessage));
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReload(ConfigReloadEvent event) {
+        updateConfigValues();
+    }
+
+    private void updateConfigValues() {
+        ConfigWrapper config = configManager.getConfigWrapper();
+        this.globalStatusEnabledMessage = config.getString("messages.status.global.enabled",
+                "&eKnockbackSync global status: &aEnabled");
+        this.globalStatusDisabledMessage = config.getString("messages.status.global.disabled",
+                "&eKnockbackSync global status: &cDisabled");
+        this.globalOffGroundStatusEnabledMessage = config.getString("messages.status.offground.enabled",
+                "&eKnockbackSync off-ground status: &aEnabled");
+        this.globalOffGroundStatusDisabledMessage = config.getString("messages.status.offground.disabled",
+                "&eKnockbackSync off-ground status: &cDisabled");
+        this.playerStatusEnabledMessage = config.getString("messages.status.player.enabled",
+                "&e%player%'s KnockbackSync status: &aEnabled");
+        this.playerStatusDisabledMessage = config.getString("messages.status.player.disabled",
+                "&e%player%'s KnockbackSync status: &cDisabled");
+        this.playerStatusGlobalDisabledMessage = config.getString("messages.status.player.global_disabled",
+                "&e%player%'s KnockbackSync status: &cDisabled (Global toggle is off)");
+        this.noSelfPermissionMessage = config.getString("messages.status.permission.no_self",
+                "&cYou do not have permission to check your knockbacksync status.");
+        this.noOtherPermissionMessage = config.getString("messages.status.permission.no_other",
+                "&cYou do not have permission to check the status of other players!");
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/subcommand/ToggleCommand.java

@@ -0,0 +1,150 @@
+package me.caseload.knockbacksync.command.subcommand;
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.ConfigWrapper;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.command.generic.PlayerSelector;
+import me.caseload.knockbacksync.event.events.ToggleOnOffEvent;
+import me.caseload.knockbacksync.manager.CombatManager;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.permission.PermissionChecker;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+import org.incendo.cloud.permission.PredicatePermission;
+
+import java.util.function.Predicate;
+
+public class ToggleCommand implements BuilderCommand {
+
+    private static final ConfigManager configManager = Base.INSTANCE.getConfigManager();
+    private static final PermissionChecker permissionChecker = Base.INSTANCE.getPermissionChecker();
+    private static final String TOGGLE_GLOBAL_PERMISSION = "knockbacksync.toggle.global";
+    private static final String TOGGLE_SELF_PERMISSION = "knockbacksync.toggle.self";
+    private static final String TOGGLE_OTHER_PERMISSION = "knockbacksync.toggle.other";
+
+    private String noGlobalPermissionMessage;
+    private String noSelfPermissionMessage;
+    private String noOtherPermissionMessage;
+    private String serverDisabledMessage;
+
+    public ToggleCommand() {
+        loadConfig();
+    }
+
+    private void loadConfig() {
+        ConfigWrapper configWrapper = configManager.getConfigWrapper();
+        noGlobalPermissionMessage = configWrapper.getString("messages.toggle.permission.no_global",
+                "&cYou don't have permission to toggle the global setting.");
+        noSelfPermissionMessage = configWrapper.getString("messages.toggle.permission.no_self",
+                "&cYou do not have permission to toggle your knockback.");
+        noOtherPermissionMessage = configWrapper.getString("messages.toggle.permission.no_other",
+                "&cYou do not have permission to toggle the knockback of other player's.");
+        serverDisabledMessage = configWrapper.getString("messages.toggle.server_disabled",
+                "&cKnockbacksync is currently disabled on this server. Contact your server administrator for more information.");
+    }
+
+    @Override
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+            manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                .literal("toggle")
+                .optional("target", Base.INSTANCE.getPlayerSelectorParser().descriptor())
+                    .permission((sender -> {
+                        Predicate<Sender> senderPredicate = (s) -> {
+                            return s.hasPermission(TOGGLE_GLOBAL_PERMISSION, false)
+                                    || sender.hasPermission(TOGGLE_SELF_PERMISSION, false)
+                                    || sender.hasPermission(TOGGLE_OTHER_PERMISSION, false);
+                        };
+
+                        return PredicatePermission.of(senderPredicate).testPermission(sender);
+                    }))
+                .handler(context -> {
+                    Sender sender = context.sender();
+                    PlayerSelector targetSelector = context.getOrDefault("target", null);
+                    if (targetSelector == null) {
+                        // Global toggle
+                        if (permissionChecker.hasPermission(sender, TOGGLE_GLOBAL_PERMISSION, false)) {
+                            toggleGlobalKnockback(sender);
+                        } else {
+                            sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', noGlobalPermissionMessage));
+                        }
+                    } else {
+                        PlatformPlayer target = targetSelector.getSinglePlayer();
+                        boolean senderIsTarget = sender.getUniqueId() == target.getUUID();
+                        if (!senderIsTarget && !permissionChecker.hasPermission(sender, TOGGLE_OTHER_PERMISSION, false)) {
+                            sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', noOtherPermissionMessage));
+                            return;
+                        } else if (senderIsTarget && !permissionChecker.hasPermission(sender, TOGGLE_SELF_PERMISSION, true)) {
+                            sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', noSelfPermissionMessage));
+                            return;
+                        }
+
+                        if (!configManager.isToggled()) {
+                            sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', serverDisabledMessage));
+                        } else {
+                            togglePlayerKnockback(target, sender);
+                        }
+                    }
+                })
+        );
+    }
+
+
+    private static void toggleGlobalKnockback(Sender sender) {
+        boolean toggledState = !configManager.isToggled();
+        ToggleOnOffEvent toggleOnOffEvent = new ToggleOnOffEvent(toggledState);
+        toggleOnOffEvent.post();
+        if (toggleOnOffEvent.isCancelled())
+            return;
+
+        toggledState = toggleOnOffEvent.getStatus();
+        configManager.setToggled(toggledState);
+
+        configManager.getConfigWrapper().set("enabled", toggledState);
+        configManager.saveConfig();
+
+        String message = ChatUtil.translateAlternateColorCodes('&',
+                toggledState ? configManager.getEnableMessage() : configManager.getDisableMessage()
+        );
+        sender.sendMessage(ChatUtil.translateAlternateColorCodes('&', message));
+    }
+
+    private static void togglePlayerKnockback(PlatformPlayer target, Sender sender) {
+        User user = target.getUser();
+        if (user == null) {
+            String message = ChatUtil.translateAlternateColorCodes('&',
+                    configManager.getPlayerDisconnectedWhileExecutingCommand()
+            ).replace("%player%", target.getName());
+            sender.sendMessage(message);
+        }
+
+        if (PlayerDataManager.shouldExempt(target.getUUID())) {
+            String message = ChatUtil.translateAlternateColorCodes('&',
+                    configManager.getPlayerIneligibleMessage()
+            ).replace("%player%", target.getName());
+
+            sender.sendMessage(message);
+            return;
+        }
+
+        boolean hasPlayerData = PlayerDataManager.containsPlayerData(user);
+        if (hasPlayerData) {
+            if (CombatManager.getPlayers().contains(user)) {
+                CombatManager.removePlayer(user);
+            }
+            PlayerDataManager.removePlayerData(user);
+        } else {
+            PlayerDataManager.addPlayerData(user, target);
+        }
+
+        String message = ChatUtil.translateAlternateColorCodes('&',
+                hasPlayerData ? configManager.getPlayerDisableMessage() : configManager.
+                        getPlayerEnableMessage()
+        ).replace("%player%", target.getName());
+
+        sender.sendMessage(message);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/command/subcommand/ToggleOffGroundSubcommand.java

@@ -0,0 +1,61 @@
+package me.caseload.knockbacksync.command.subcommand;
+
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.ConfigWrapper;
+import me.caseload.knockbacksync.command.generic.BuilderCommand;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.sender.Sender;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.incendo.cloud.CommandManager;
+import org.incendo.cloud.permission.PredicatePermission;
+
+import java.util.function.Predicate;
+
+public class ToggleOffGroundSubcommand implements BuilderCommand {
+
+    public static boolean offGroundSyncEnabled = true;
+    private String offGroundSyncEnableMessage;
+    private String offGroundSyncDisableMessage;
+
+    public ToggleOffGroundSubcommand() {
+        loadConfigSettings();
+    }
+
+    public void register(CommandManager<Sender> manager) {
+        manager.command(
+            manager.commandBuilder("knockbacksync", "kbsync", "kbs")
+                .literal("toggleoffground")
+                .permission((sender -> {
+                    final String permission = "knockbacksync.toggleoffground";
+                    Predicate<Sender> senderPredicate = (s) -> {
+                        return s.hasPermission(permission, false);
+                    };
+
+                    return PredicatePermission.of(senderPredicate).testPermission(sender);
+                }))
+                .handler(commandContext -> {
+                    offGroundSyncEnabled = !offGroundSyncEnabled;
+                    Base.INSTANCE.getConfigManager().getConfigWrapper().set("enable_offground_synchronization", offGroundSyncEnabled);
+                    Base.INSTANCE.getConfigManager().saveConfig();
+                    String message = ChatUtil.translateAlternateColorCodes('&',
+                            offGroundSyncEnabled ? offGroundSyncEnableMessage : offGroundSyncDisableMessage);
+                    commandContext.sender().sendMessage(message);
+                }));
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReloadEvent(ConfigReloadEvent event) {
+        loadConfigSettings();
+    }
+
+    private void loadConfigSettings() {
+        ConfigWrapper configWrapper = Base.INSTANCE.getConfigManager().getConfigWrapper();
+        offGroundSyncEnabled = configWrapper.getBoolean("enable_offground_synchronization", true);
+        this.offGroundSyncEnableMessage = configWrapper.getString("messages.offground.enable",
+                "&aSuccessfully enabled offground synchronization.");
+        this.offGroundSyncDisableMessage = configWrapper.getString("messages.offground.disable",
+                "&cSuccessfully disabled offground synchronization.");
+    }
+}

common/src/main/java/me/caseload/knockbacksync/config/YamlConfiguration.java

@@ -0,0 +1,177 @@
+package me.caseload.knockbacksync.config;
+
+import lombok.Getter;
+import lombok.Setter;
+import org.yaml.snakeyaml.DumperOptions;
+import org.yaml.snakeyaml.Yaml;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.*;
+
+public class YamlConfiguration {
+    private final File file;
+    private final Yaml yaml;
+    @Getter
+    @Setter
+    private Map<String, Object> data;
+    private String fileContents;
+
+    public YamlConfiguration(File file) {
+        this.file = file;
+        DumperOptions options = new DumperOptions();
+        options.setDefaultFlowStyle(DumperOptions.FlowStyle.BLOCK);
+        options.setPrettyFlow(true);
+        options.setWidth(Integer.MAX_VALUE);
+        this.yaml = new Yaml(options);
+    }
+
+    public void load() throws IOException {
+        if (!file.exists()) {
+            data = new LinkedHashMap<>();
+            return;
+        }
+
+        fileContents = new String(Files.readAllBytes(file.toPath()), StandardCharsets.UTF_8);
+        data = yaml.load(fileContents);
+        if (data == null) {
+            data = new LinkedHashMap<>();
+        }
+    }
+
+    public void save() throws IOException {
+        if (!file.exists()) {
+            file.getParentFile().mkdirs();
+            file.createNewFile();
+        }
+
+        String dump = yaml.dump(data);
+
+        if (fileContents != null) {
+            Map<String, YamlElement> oldElements = parseYaml(fileContents);
+            Map<String, YamlElement> newElements = parseYaml(dump);
+
+            StringBuilder result = new StringBuilder();
+            buildOutput(oldElements, newElements, result);
+            dump = result.toString();
+        }
+
+        try (Writer writer = new OutputStreamWriter(Files.newOutputStream(file.toPath()), StandardCharsets.UTF_8)) {
+            writer.write(dump);
+        }
+    }
+
+    private static class YamlElement {
+        String key;
+        String value;
+        int indent;
+        boolean isComment;
+        List<YamlElement> children = new ArrayList<>();
+
+        YamlElement(String line, int indent) {
+            this.indent = indent;
+            if (line.trim().startsWith("#")) {
+                this.isComment = true;
+                this.value = line;
+            } else {
+                this.isComment = false;
+                String[] parts = line.split(":", 2);
+                this.key = parts[0].trim();
+                this.value = parts.length > 1 ? parts[1].trim() : "";
+            }
+        }
+    }
+
+    private Map<String, YamlElement> parseYaml(String content) {
+        Map<String, YamlElement> elements = new LinkedHashMap<>();
+        Stack<YamlElement> stack = new Stack<>();
+        String[] lines = content.split("\n");
+
+        for (String line : lines) {
+            if (line.trim().isEmpty()) continue;
+
+            int indent = getIndentation(line);
+            YamlElement element = new YamlElement(line, indent);
+
+            while (!stack.isEmpty() && stack.peek().indent >= indent) {
+                stack.pop();
+            }
+
+            if (stack.isEmpty()) {
+                if (!element.isComment) {
+                    elements.put(element.key, element);
+                } else {
+                    elements.put("comment" + elements.size(), element);
+                }
+            } else {
+                stack.peek().children.add(element);
+            }
+
+            if (!element.isComment && element.value.isEmpty()) {
+                stack.push(element);
+            }
+        }
+
+        return elements;
+    }
+
+    private void buildOutput(Map<String, YamlElement> oldElements, Map<String, YamlElement> newElements, StringBuilder result) {
+        for (YamlElement element : oldElements.values()) {
+            if (element.isComment) {
+                result.append(element.value).append("\n");
+            } else {
+                YamlElement newElement = newElements.get(element.key);
+                if (newElement != null) {
+                    String indent = createIndent(element.indent);
+                    result.append(indent).append(element.key).append(":");
+
+                    if (!newElement.value.isEmpty()) {
+                        result.append(" ").append(newElement.value);
+                    }
+                    result.append("\n");
+
+                    if (!element.children.isEmpty()) {
+                        Map<String, YamlElement> oldChildren = new LinkedHashMap<>();
+                        Map<String, YamlElement> newChildren = new LinkedHashMap<>();
+
+                        for (YamlElement child : element.children) {
+                            if (!child.isComment) {
+                                oldChildren.put(child.key, child);
+                            } else {
+                                oldChildren.put("comment" + oldChildren.size(), child);
+                            }
+                        }
+
+                        for (YamlElement child : newElement.children) {
+                            if (!child.isComment) {
+                                newChildren.put(child.key, child);
+                            }
+                        }
+
+                        buildOutput(oldChildren, newChildren, result);
+                    }
+                }
+            }
+        }
+    }
+
+    private int getIndentation(String line) {
+        int indent = 0;
+        while (indent < line.length() && line.charAt(indent) == ' ') {
+            indent++;
+        }
+        return indent;
+    }
+
+    private String createIndent(int count) {
+        StringBuilder sb = new StringBuilder(count);
+        for (int i = 0; i < count; i++) {
+            sb.append(' ');
+        }
+        return sb.toString();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/event/Event.java

@@ -0,0 +1,23 @@
+package me.caseload.knockbacksync.event;
+
+import lombok.Setter;
+import me.caseload.knockbacksync.event.OptimizedEventBus;
+
+public abstract class Event {
+    @Setter
+    private static EventBus eventBus;
+    @Setter
+    private boolean cancelled = false;
+
+    public void post() {
+        if (eventBus != null) {
+            eventBus.post(this);
+        } else {
+            throw new IllegalStateException("EventBus has not been set");
+        }
+    }
+
+    public boolean isCancelled() {
+        return cancelled;
+    }
+}

common/src/main/java/me/caseload/knockbacksync/event/EventBus.java

@@ -0,0 +1,13 @@
+package me.caseload.knockbacksync.event;
+
+public interface EventBus {
+    void registerListeners(Object listener);
+
+    void registerStaticListeners(Class<?> clazz);
+
+    void unregisterListeners(Object listener);
+
+    void unregisterStaticListeners(Class<?> clazz);
+
+    void post(Event event);
+}

common/src/main/java/me/caseload/knockbacksync/event/KBSyncEventHandler.java

@@ -0,0 +1,12 @@
+package me.caseload.knockbacksync.event;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface KBSyncEventHandler {
+    int priority() default 0;
+}

common/src/main/java/me/caseload/knockbacksync/event/OptimizedEventBus.java

@@ -0,0 +1,101 @@
+package me.caseload.knockbacksync.event;
+
+import java.lang.invoke.MethodHandle;
+import java.lang.invoke.MethodHandles;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+public class OptimizedEventBus implements EventBus {
+    // ordinarily this would just be a hashmap since we don't modify it on different threads, but Folia forces us to make it concurrent
+    private final Map<Class<? extends Event>, List<OptimizedListener>> listenerMap = new ConcurrentHashMap<>();
+    private final MethodHandles.Lookup lookup = MethodHandles.lookup();
+
+    @Override
+    public void registerListeners(Object listener) {
+        registerMethods(listener, listener.getClass());
+    }
+
+    @Override
+    public void registerStaticListeners(Class<?> clazz) {
+        registerMethods(null, clazz);
+    }
+
+    private void registerMethods(Object instance, Class<?> clazz) {
+        for (Method method : clazz.getDeclaredMethods()) {
+            KBSyncEventHandler annotation = method.getAnnotation(KBSyncEventHandler.class);
+            if (annotation != null && method.getParameterCount() == 1) {
+                Class<?> eventType = method.getParameterTypes()[0];
+                if (Event.class.isAssignableFrom(eventType)) {
+                    try {
+                        // Skip instance methods when registering static listeners
+                        if (instance == null && !Modifier.isStatic(method.getModifiers())) {
+                            continue;
+                        }
+
+                        MethodHandle handle = lookup.unreflect(method);
+                        OptimizedListener optimizedListener = new OptimizedListener(instance, handle, annotation.priority(), method.getDeclaringClass());
+                        // Yes the CopyOnWriteArrayList is slow, yes we need to for thread safety on Folia, we'll replace when performance problems actually crop up
+                        listenerMap.computeIfAbsent((Class<? extends Event>) eventType, k -> new CopyOnWriteArrayList<>()).add(optimizedListener);
+                    } catch (IllegalAccessException e) {
+                        e.printStackTrace();
+                    }
+                }
+            }
+        }
+        // Sort listeners by priority
+        listenerMap.values().forEach(list -> list.sort((a, b) -> Integer.compare(b.priority, a.priority)));
+    }
+
+    @Override
+    public void unregisterListeners(Object listener) {
+        listenerMap.values().forEach(list -> list.removeIf(l -> l.instance == listener));
+    }
+
+    @Override
+    public void unregisterStaticListeners(Class<?> clazz) {
+        listenerMap.values().forEach(list -> list.removeIf(l -> l.instance == null && l.declaringClass == clazz));
+    }
+
+    @Override
+    public void post(Event event) {
+        List<OptimizedListener> listeners = listenerMap.get(event.getClass());
+        if (listeners != null) {
+            for (OptimizedListener listener : listeners) {
+                try {
+                    if (listener.instance != null) {
+                        // Instance method
+                        listener.handle.invoke(listener.instance, event);
+                    } else {
+                        // Static method
+                        listener.handle.invoke(event);
+                    }
+                    if (event.isCancelled()) {
+                        break;
+                    }
+                } catch (Throwable throwable) {
+                    throwable.printStackTrace();
+                }
+            }
+        }
+    }
+
+    private static class OptimizedListener {
+        final Object instance; // null for static methods
+        final MethodHandle handle;
+        final int priority;
+        final Class<?> declaringClass;
+
+        OptimizedListener(Object instance, MethodHandle handle, int priority, Class<?> declaringClass) {
+            this.instance = instance;
+            this.handle = handle;
+            this.priority = priority;
+            this.declaringClass = declaringClass;
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/event/events/ConfigReloadEvent.java

@@ -0,0 +1,15 @@
+package me.caseload.knockbacksync.event.events;
+
+import lombok.Getter;
+import me.caseload.knockbacksync.event.Event;
+import me.caseload.knockbacksync.manager.ConfigManager;
+
+@Getter
+public class ConfigReloadEvent extends Event {
+    private final ConfigManager configManager;
+
+    public ConfigReloadEvent(ConfigManager configManager) {
+        this.configManager = configManager;
+    }
+
+}

common/src/main/java/me/caseload/knockbacksync/event/events/ToggleOnOffEvent.java

@@ -0,0 +1,24 @@
+package me.caseload.knockbacksync.event.events;
+
+import me.caseload.knockbacksync.event.Event;
+
+public class ToggleOnOffEvent extends Event {
+
+    private boolean newEnabledState;
+
+    public ToggleOnOffEvent(boolean newEnabledState) {
+        this.newEnabledState = newEnabledState;
+    }
+
+    public boolean getStatus() {
+        return newEnabledState;
+    }
+
+    public void setStatus(boolean newEnabledState) {
+        this.newEnabledState = newEnabledState;
+    }
+    @Override
+    public void setCancelled(boolean cancelled) {
+        super.setCancelled(cancelled);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/listener/PlayerDamageListener.java

@@ -0,0 +1,47 @@
+package me.caseload.knockbacksync.listener;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.util.LegacyKnockback;
+
+public abstract class PlayerDamageListener {
+    public void onPlayerDamage(PlatformPlayer victim, PlatformPlayer attacker) {
+        ConfigManager config = Base.INSTANCE.getConfigManager();
+        if (!config.isToggled())
+            return;
+
+        User user = victim.getUser();
+        if (user == null) return; // Prevent errors with players disconnecting while this is running (or with fake player?)
+
+        PlayerData playerData = PlayerDataManager.getPlayerData(user);
+        if (playerData == null)
+            return;
+
+        if (config.isLegacyKnockbackEnabled()) {
+            if (playerData.isRodKnockbackPending()) {
+                // A fishing-rod (bobber-direction) knockback was already supplied for this hit via
+                // the rod API. Keep it instead of overwriting with the melee formula; the velocity
+                // event still owns + latency-syncs it. Its vertical was set by the API call.
+            } else {
+                // KnockbackSync owns the full 1.8 melee velocity. Compute it now (we have the
+                // attacker here) and store it for the PlayerVelocityEvent to apply + sync.
+                Vector3d legacy = LegacyKnockback.compute(victim, attacker, playerData, config);
+                playerData.setLegacyKnockback(legacy);
+                // On-ground sync should target the legacy vertical value, not the 1.9 one.
+                playerData.setVerticalVelocity(legacy.getY());
+            }
+        } else {
+            playerData.setVerticalVelocity(playerData.calculateVerticalVelocity(attacker)); // do not move this calculation
+        }
+        playerData.setLastDamageTicks(victim.getNoDamageTicks());
+        playerData.updateCombat();
+
+        if (!Base.INSTANCE.getConfigManager().isRunnableEnabled())
+            playerData.sendPing(true);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/listener/PlayerKnockbackListener.java

@@ -0,0 +1,82 @@
+package me.caseload.knockbacksync.listener;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.protocol.world.states.WrappedBlockState;
+import com.github.retrooper.packetevents.protocol.world.states.type.StateTypes;
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import org.jetbrains.annotations.Nullable;
+
+public abstract class PlayerKnockbackListener {
+
+    /**
+     * Computes the melee velocity to apply to the victim.
+     *
+     * <p>The returned value, when non-null, MUST be written back by the platform layer.
+     * Bukkit writes it to the {@code PlayerVelocityEvent} (so KnockbackSync is the last,
+     * authoritative writer in the event chain rather than reading/writing the player's
+     * live velocity out-of-band — see issue #7).</p>
+     *
+     * <p>When legacy (1.8) knockback is enabled, the 1.8 vector computed at damage time
+     * replaces vanilla X/Z/Y, and latency Y-correction is applied on top of it. In that
+     * mode this method always returns a velocity (the raw 1.8 vector when no correction
+     * applies), so KnockbackSync owns the final melee velocity.</p>
+     *
+     * @return the velocity to apply, or {@code null} to leave the velocity unchanged.
+     */
+    @Nullable
+    public Vector3d onPlayerVelocity(PlatformPlayer victim, Vector3d velocity) {
+        ConfigManager config = Base.INSTANCE.getConfigManager();
+        if (!config.isToggled())
+            return null;
+
+        User user = victim.getUser();
+        if (user == null) return null; // Prevent errors with players disconnecting while this is running (or with fake player?)
+
+        PlayerData victimPlayerData = PlayerDataManager.getPlayerData(user);
+        if (victimPlayerData == null)
+            return null;
+
+        // Legacy 1.8 knockback: KnockbackSync owns the melee velocity. The 1.8 vector
+        // (computed at damage time) replaces vanilla X/Z/Y. We still apply latency
+        // Y-correction on top when conditions allow; otherwise the raw 1.8 vector is
+        // applied. legacyKb == null means either legacy is off or none is pending, in
+        // which case behaviour falls back to the original (Y-sync of the event velocity).
+        Vector3d legacyKb = config.isLegacyKnockbackEnabled() ? victimPlayerData.consumeLegacyKnockback() : null;
+        Vector3d base = (legacyKb != null) ? legacyKb : velocity;
+
+        if (victimPlayerData.getNotNullPing() < PlayerData.PING_OFFSET)
+            return legacyKb;
+
+        double distanceToGround = victimPlayerData.getDistanceToGround();
+        if (distanceToGround <= 0)
+            return legacyKb; // minecraft already does the work for us
+
+        WrappedBlockState blockState = victim.getWorld().getBlockStateAt(victim.getLocation());
+        if (victim.isGliding() ||
+                blockState.getType() == StateTypes.WATER ||
+                blockState.getType() == StateTypes.LAVA ||
+                blockState.getType() == StateTypes.COBWEB ||
+                blockState.getType() == StateTypes.SCAFFOLDING)
+            return legacyKb;
+
+        Vector3d adjustedVelocity;
+        if (victimPlayerData.isOnGroundClientSide(base.getY(), distanceToGround)) {
+            Integer damageTicks = victimPlayerData.getLastDamageTicks();
+            if (damageTicks != null && damageTicks > 8)
+                return legacyKb;
+
+            adjustedVelocity = base.withY(victimPlayerData.getVerticalVelocity()); // Should be impossible to produce a NPE in this context
+        }
+        else if (victimPlayerData.isOffGroundSyncEnabled())
+            adjustedVelocity = base.withY(victimPlayerData.getCompensatedOffGroundVelocity());
+        else
+            return legacyKb;
+
+        return adjustedVelocity;
+    }
+}

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/AttributeChangeListener.java

@@ -1,15 +1,16 @@
-package me.caseload.knockbacksync.listener;
+package me.caseload.knockbacksync.listener.packetevents;
 
 import com.github.retrooper.packetevents.event.PacketListenerAbstract;
 import com.github.retrooper.packetevents.event.PacketSendEvent;
 import com.github.retrooper.packetevents.protocol.attribute.Attributes;
 import com.github.retrooper.packetevents.protocol.packettype.PacketType;
 import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
 import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerUpdateAttributes;
-import me.caseload.knockbacksync.manager.PlayerData;
+import me.caseload.knockbacksync.Base;
 import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlayerData;
 import me.caseload.knockbacksync.util.MathUtil;
-import org.bukkit.entity.Player;
 
 import java.util.List;
 import java.util.UUID;
@@ -19,9 +20,9 @@ public class AttributeChangeListener extends PacketListenerAbstract {
     public static final UUID SPRINTING_MODIFIER_UUID =
             UUID.fromString("662A6B8D-DA3E-4C1C-8813-96EA6097278D");
 
-    double minGravity = -1;
-    double maxGravity = 1;
-    double defaultGravity = 0.08;
+    final double minGravity = -1;
+    final double maxGravity = 1;
+    final double defaultGravity = 0.08;
     double currentGravity;
 
     public AttributeChangeListener() {
@@ -30,23 +31,23 @@ public class AttributeChangeListener extends PacketListenerAbstract {
 
     @Override
     public void onPacketSend(PacketSendEvent event) {
-        // Intercept the packet that updates entity properties (attributes)
-        if (event.getPacketType() != PacketType.Play.Server.UPDATE_ATTRIBUTES)
-            return;
+        if (!Base.INSTANCE.getConfigManager().isToggled()) return;
 
-        WrapperPlayServerUpdateAttributes packet = new WrapperPlayServerUpdateAttributes(event);
+        if (event.getPacketType() == PacketType.Play.Server.UPDATE_ATTRIBUTES) {
 
-        // Check if the entity is a player
-        Player player = event.getPlayer();
-        if (player == null || !PlayerDataManager.containsPlayerData(player.getUniqueId()))
-            return;
+            WrapperPlayServerUpdateAttributes packet = new WrapperPlayServerUpdateAttributes(event);
 
-        // Get the attributes from the packet
-        for (WrapperPlayServerUpdateAttributes.Property property : packet.getProperties()) {
-            // You can now check for specific attributes
-            if (property.getAttribute().equals(Attributes.GENERIC_GRAVITY)) {
-                onPlayerGravityChange(player, calculateValueWithModifiers(property));
-                break;
+            User user = event.getUser();
+            if (!PlayerDataManager.containsPlayerData(user)) return;
+
+            // Get the attributes from the packet
+            for (WrapperPlayServerUpdateAttributes.Property property : packet.getProperties()) {
+                // You can now check for specific attributes
+                if (property.getAttribute().equals(Attributes.GENERIC_GRAVITY)) {
+                    onPlayerGravityChange(user, calculateValueWithModifiers(property));
+                } else if (property.getAttribute().equals(Attributes.GENERIC_KNOCKBACK_RESISTANCE)) {
+                    onPlayerKnockBackChange(user, calculateValueWithModifiers(property));
+                }
             }
         }
     }
@@ -86,12 +87,17 @@ public class AttributeChangeListener extends PacketListenerAbstract {
 
     // Yes this is not properly latency compensated, that would require including a proper simulation engine
     // Laggy players will just have to deal with being on the wrong gravity for a few hundred ms, too bad!
-    public void onPlayerGravityChange(Player player, double newGravity) {
-        PlayerData playerData = PlayerDataManager.getPlayerData(player.getUniqueId());
+    public void onPlayerGravityChange(User user, double newGravity) {
+        PlayerData playerData = PlayerDataManager.getPlayerData(user);
         if (playerData.getClientVersion().isNewerThanOrEquals(ClientVersion.V_1_20_5)) {
-            playerData.setGravity(newGravity);
+            playerData.setGravityAttribute(newGravity);
         } else {
             currentGravity = defaultGravity;
         }
     }
+
+    private void onPlayerKnockBackChange(User user, double newKnockbackResistance) {
+        PlayerData playerData = PlayerDataManager.getPlayerData(user);
+        playerData.setKnockbackResistanceAttribute(newKnockbackResistance);
+    }
 }

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/ClientBrandListener.java

@@ -0,0 +1,41 @@
+package me.caseload.knockbacksync.listener.packetevents;
+
+import com.github.retrooper.packetevents.event.PacketListenerAbstract;
+import com.github.retrooper.packetevents.event.PacketReceiveEvent;
+import com.github.retrooper.packetevents.protocol.packettype.PacketType;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPluginMessage;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlayerData;
+
+public class ClientBrandListener extends PacketListenerAbstract {
+    String brand = "vanilla";
+    boolean hasBrand = false;
+
+    @Override
+    public void onPacketReceive(final PacketReceiveEvent event) {
+        if (event.getPacketType() == PacketType.Play.Client.PLUGIN_MESSAGE) {
+            WrapperPlayClientPluginMessage packet = new WrapperPlayClientPluginMessage(event);
+            String channelName = packet.getChannelName();
+            handle(channelName, packet.getData());
+            PlayerData playerData = PlayerDataManager.getPlayerData(event.getUser());
+            if (playerData == null) return;
+            playerData.getPlatformPlayer().setClientBrand(brand);
+        }
+    }
+
+    public void handle(String channel, byte[] data) {
+        if (channel.equalsIgnoreCase("minecraft:brand") || // 1.13+
+                channel.equals("MC|Brand")) { // 1.12
+            if (data.length > 64 || data.length == 0) {
+                brand = "sent " + data.length + " bytes as brand";
+            } else if (!hasBrand) {
+                byte[] minusLength = new byte[data.length - 1];
+                System.arraycopy(data, 1, minusLength, 0, minusLength.length);
+                brand = new String(minusLength).replace(" (Velocity)", ""); //removes velocity's brand suffix
+            }
+            hasBrand = true;
+        }
+    }
+}
+

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/PacketPlayerJoinQuit.java

@@ -0,0 +1,51 @@
+package me.caseload.knockbacksync.listener.packetevents;
+
+import com.github.retrooper.packetevents.event.PacketListenerAbstract;
+import com.github.retrooper.packetevents.event.UserDisconnectEvent;
+import com.github.retrooper.packetevents.event.UserLoginEvent;
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.google.common.base.Preconditions;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.util.ChatUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.UUID;
+
+public class PacketPlayerJoinQuit extends PacketListenerAbstract {
+    @Override
+    public void onUserLogin(UserLoginEvent event) {
+        Object nativePlayerObject = event.getPlayer();
+        Preconditions.checkArgument(nativePlayerObject != null);
+
+        @NotNull PlatformPlayer platformPlayer = Base.INSTANCE.getPlatformServer().getPlayer(nativePlayerObject);
+        onPlayerJoin(event.getUser(), platformPlayer);
+    }
+
+    @Override
+    public void onUserDisconnect(UserDisconnectEvent event) {
+        onPlayerQuit(event.getUser());
+    }
+
+    public void onPlayerJoin(User user, PlatformPlayer player) {
+        PlayerDataManager.addPlayerData(user, player);
+
+        if (Base.INSTANCE.getConfigManager().isUpdateAvailable() && Base.INSTANCE.getConfigManager().isNotifyUpdate() && Base.INSTANCE.getPermissionChecker().hasPermission(player, "knockbacksync.update"))
+            player.sendMessage(ChatUtil.translateAlternateColorCodes(
+                    '&',
+                    "&6An updated version of &eKnockbackSync &6is now available for download at: &bhttps://github.com/CASELOAD7000/knockback-sync/releases/latest"
+            ));
+    }
+
+    public void onPlayerQuit(@NotNull User user) {
+        PlayerData playerData = PlayerDataManager.getPlayerData(user);
+        if (playerData == null)
+            return;
+
+        playerData.quitCombat(true);
+        PlayerDataManager.removePlayerData(user);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/PingReceiveListener.java

@@ -0,0 +1,101 @@
+package me.caseload.knockbacksync.listener.packetevents;
+
+import com.github.retrooper.packetevents.event.*;
+import com.github.retrooper.packetevents.protocol.packettype.PacketType;
+import com.github.retrooper.packetevents.protocol.packettype.PacketTypeCommon;
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientKeepAlive;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPong;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientWindowConfirmation;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PingStrategy;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.util.data.Pair;
+
+import java.util.Queue;
+import java.util.UUID;
+
+public class PingReceiveListener extends PacketListenerAbstract {
+
+    public PingReceiveListener() {
+        super(PacketListenerPriority.LOWEST);
+    }
+
+    @Override
+    public void onPacketReceive(PacketReceiveEvent event) {
+        // Do not immediately return if KB sync is disabled. This is because if we send a packet, disable the plugin
+        // And then receive a response we have to ensure that if the packet was sent by us we cancel it
+        // otherwise the server will likely kick the player
+        PacketTypeCommon packetType = event.getPacketType();
+        User user = event.getUser();
+        if (user == null) return;
+        PlayerData playerData = PlayerDataManager.getPlayerData(user);
+        if (playerData == null) return;
+
+        // Cancel echoes of injected packets before any strategy check: on 1.20.2+ an unexpected keepalive is an instant "Timed out" kick, so a strategy switch mid-flight must not leak one.
+        if (packetType == PacketType.Play.Client.KEEP_ALIVE) {
+            WrapperPlayClientKeepAlive keepAlive = new WrapperPlayClientKeepAlive(event);
+            long receivedId = keepAlive.getId();
+
+            if (playerData.didWeSendThatPacket(receivedId))
+                event.setCancelled(true);
+
+            if (playerData.pingStrategy == PingStrategy.KEEPALIVE)
+                handlePingCalculationPackets(playerData, receivedId, playerData.keepaliveMap);
+        } else if (packetType == PacketType.Play.Client.PONG) {
+            WrapperPlayClientPong pong = new WrapperPlayClientPong(event);
+            int id = pong.getId();
+
+            if (playerData.didWeSendThatPacket(id))
+                event.setCancelled(true);
+
+            if (playerData.pingStrategy == PingStrategy.TRANSACTION)
+                handlePingCalculationPackets(playerData, id, playerData.transactionsSent);
+        } else if (packetType == PacketType.Play.Client.WINDOW_CONFIRMATION) {
+            WrapperPlayClientWindowConfirmation windowConfirmation = new WrapperPlayClientWindowConfirmation(event);
+            int id = windowConfirmation.getActionId();
+
+            if (playerData.didWeSendThatPacket(id))
+                event.setCancelled(true);
+
+            if (playerData.pingStrategy == PingStrategy.TRANSACTION)
+                handlePingCalculationPackets(playerData, id, playerData.transactionsSent);
+        }
+    }
+
+    private <T extends Number> void handlePingCalculationPackets(PlayerData playerData, long id, Queue<Pair<T, Long>> packetSentList) {
+//        System.out.println("Received response ID: " + id + " Queue size before: " + packetSentList.size());
+//        System.out.println("Current queue contents: " + packetSentList.toString());
+
+        if (!Base.INSTANCE.getConfigManager().isToggled()) return;
+
+        Pair<T, Long> data = null;
+        int cleared = 0;
+        // Keep polling until we find the matching ID
+        do {
+            data = packetSentList.poll();
+            cleared++;
+
+            if (data == null) {
+//                System.out.println("No data found in queue!");
+                break;
+            }
+
+//            System.out.println("Cleared entry " + cleared + ": ID=" + data.getFirst() + " Time=" + data.getSecond());
+
+            long pingNanos = (System.nanoTime() - data.getSecond());
+            double diffMillisDouble = pingNanos / 1_000_000.0;
+
+            playerData.setPreviousPing(playerData.getPing());
+            playerData.setPing(diffMillisDouble);
+
+            playerData.getJitterCalculator().addPing(pingNanos);
+            double jitter = playerData.getJitterCalculator().calculateJitter();
+            playerData.setJitter(jitter);
+
+        } while (data.getFirst().longValue() != id);
+
+//        System.out.println("Finished processing - Cleared " + cleared + " entries. Queue size after: " + packetSentList.size());
+    }
+}

common/src/main/java/me/caseload/knockbacksync/listener/packetevents/PingSendListener.java

@@ -0,0 +1,57 @@
+package me.caseload.knockbacksync.listener.packetevents;
+
+import com.github.retrooper.packetevents.event.*;
+import com.github.retrooper.packetevents.protocol.packettype.PacketType;
+import com.github.retrooper.packetevents.protocol.packettype.PacketTypeCommon;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientKeepAlive;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientPong;
+import com.github.retrooper.packetevents.wrapper.play.client.WrapperPlayClientWindowConfirmation;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerKeepAlive;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerPing;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerWindowConfirmation;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PingStrategy;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.util.data.Pair;
+
+import java.util.Queue;
+import java.util.UUID;
+
+public class PingSendListener extends PacketListenerAbstract {
+
+    public PingSendListener() {
+        // See all actually outgoing, not cancelled, ping packets
+        super(PacketListenerPriority.MONITOR);
+    }
+
+    @Override
+    public void onPacketSend(PacketSendEvent event) {
+        if (!Base.INSTANCE.getConfigManager().isToggled()) return;
+        if (event.isCancelled()) return;
+
+        PacketTypeCommon packetType = event.getPacketType();
+        UUID playerUUID = event.getUser().getUUID();
+        if (playerUUID == null) return;
+        PlayerData playerData = PlayerDataManager.getPlayerData(event.getUser());
+        if (playerData == null) return;
+
+        if (playerData.pingStrategy == PingStrategy.KEEPALIVE && packetType.equals(PacketType.Play.Server.KEEP_ALIVE)) {
+            WrapperPlayServerKeepAlive keepAlive = new WrapperPlayServerKeepAlive(event);
+            long id = keepAlive.getId();
+
+//            System.out.println("Adding ping to queue - ID: " + id + " Time: " + System.nanoTime() + " Queue size before: " + playerData.keepaliveMap.size());
+            playerData.keepaliveMap.add(new Pair<>(id, System.nanoTime()));
+        } else if (playerData.pingStrategy == PingStrategy.TRANSACTION && packetType.equals(PacketType.Play.Server.PING)) {
+            WrapperPlayServerPing ping = new WrapperPlayServerPing(event);
+            int id = ping.getId();
+
+            playerData.transactionsSent.add(new Pair<>(id, System.nanoTime()));
+        } else if (playerData.pingStrategy == PingStrategy.TRANSACTION && packetType.equals(PacketType.Play.Server.WINDOW_CONFIRMATION)) {
+            WrapperPlayServerWindowConfirmation confirmation = new WrapperPlayServerWindowConfirmation(event);
+            int id = confirmation.getActionId();
+
+            playerData.transactionsSent.add(new Pair<>(id, System.nanoTime()));
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/manager/CombatManager.java

@@ -0,0 +1,25 @@
+package me.caseload.knockbacksync.manager;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.Set;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class CombatManager {
+
+    private static final Set<@NotNull User> combatPlayers = ConcurrentHashMap.newKeySet();
+
+    public static @NotNull Set<@NotNull User> getPlayers() {
+        return combatPlayers;
+    }
+
+    public static void addPlayer(@NotNull User user) {
+        combatPlayers.add(user);
+    }
+
+    public static void removePlayer(@NotNull User user) {
+        combatPlayers.remove(user);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/manager/ConfigManager.java

@@ -0,0 +1,199 @@
+package me.caseload.knockbacksync.manager;
+
+import lombok.Getter;
+import lombok.Setter;
+import me.caseload.knockbacksync.ConfigWrapper;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.Platform;
+import me.caseload.knockbacksync.config.YamlConfiguration;
+import me.caseload.knockbacksync.runnable.PingRunnable;
+import me.caseload.knockbacksync.scheduler.AbstractTaskHandle;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.util.HashMap;
+import java.util.Map;
+
+@Getter
+@Setter
+public class ConfigManager {
+
+    public static final long CONFIG_VERSION = 9;
+
+    private boolean toggled;
+    private boolean runnableEnabled;
+    private boolean updateAvailable;
+    private boolean notifyUpdate;
+    private boolean autoUpdate;
+
+    // Legacy (1.8) knockback: makes KnockbackSync the single owner of melee velocity,
+    // reproducing OldCombatMechanics' old-player-knockback values while still latency-syncing.
+    private boolean legacyKnockbackEnabled;
+    private double legacyKnockbackHorizontal;
+    private double legacyKnockbackVertical;
+    private double legacyKnockbackVerticalLimit;
+    private double legacyKnockbackExtraHorizontal;
+    private double legacyKnockbackExtraVertical;
+    private boolean legacyKnockbackResistanceEnabled;
+
+    private long runnableInterval;
+    private long combatTimer;
+    private long spikeThreshold;
+
+    private String enableMessage;
+    private String disableMessage;
+    private String playerEnableMessage;
+    private String playerDisableMessage;
+    private String playerIneligibleMessage;
+    private String playerDisconnectedWhileExecutingCommand;
+
+    private AbstractTaskHandle pingTask;
+
+    private Map<String, Object> config;
+    private File configFile;
+    private ConfigWrapper configWrapper; // Cache the ConfigWrapper instance
+    private YamlConfiguration yamlConfig;
+
+    public ConfigManager() {
+        Base instance = Base.INSTANCE;
+        configFile = new File(instance.getDataFolder(), "config.yml");
+        yamlConfig = new YamlConfiguration(configFile);
+    }
+
+    public ConfigWrapper getConfigWrapper() {
+        if (configWrapper == null) {
+            reloadConfig();
+        }
+        return configWrapper;
+    }
+
+    public void reloadConfig() {
+        try {
+            if (!configFile.exists()) {
+                Base.INSTANCE.saveDefaultConfig();
+            }
+            yamlConfig.load();
+            config = yamlConfig.getData();
+            configWrapper = new ConfigWrapper(config);
+        } catch (IOException e) {
+            e.printStackTrace();
+            config = new HashMap<>();
+            configWrapper = new ConfigWrapper(config);
+        }
+    }
+
+    public void saveConfig() {
+        try {
+            yamlConfig.setData(config);
+            yamlConfig.save();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+
+    public void loadConfig(boolean reloadConfig) {
+        if (reloadConfig || config == null) {
+            reloadConfig();
+        }
+
+        ConfigWrapper configWrapper = getConfigWrapper(); // Use cached ConfigWrapper
+
+        updateConfig();
+
+        toggled = configWrapper.getBoolean("enabled", true);
+
+        boolean newRunnableEnabled = configWrapper.getBoolean("runnable.enabled", true);
+        // Always stop the previous ping task on reload (reschedule below only if still enabled); gating the cancel on staying enabled leaked the task when disabling via reload.
+        if (pingTask != null) { // null on first startup
+            pingTask.cancel();
+            pingTask = null;
+        }
+
+        runnableEnabled = newRunnableEnabled;
+        runnableInterval = configWrapper.getLong("runnable.interval", 5L);
+
+        if (runnableEnabled) {
+            long initialDelay = 0L;
+            long pingTaskRunnableInterval = runnableInterval;
+            // Folia does not allow 0 ticks of wait time
+            if (Base.INSTANCE.getPlatform() == Platform.FOLIA) {
+                initialDelay = 1L;
+                pingTaskRunnableInterval = Math.max(pingTaskRunnableInterval, 1L);
+            }
+            pingTask = Base.INSTANCE.getScheduler().runTaskTimerAsynchronously(new PingRunnable(), initialDelay, pingTaskRunnableInterval);
+        }
+
+        legacyKnockbackEnabled = configWrapper.getBoolean("legacy_knockback.enabled", false);
+        legacyKnockbackHorizontal = configWrapper.getDouble("legacy_knockback.horizontal", 0.4);
+        legacyKnockbackVertical = configWrapper.getDouble("legacy_knockback.vertical", 0.4);
+        legacyKnockbackVerticalLimit = configWrapper.getDouble("legacy_knockback.vertical_limit", 0.4);
+        legacyKnockbackExtraHorizontal = configWrapper.getDouble("legacy_knockback.extra_horizontal", 0.5);
+        legacyKnockbackExtraVertical = configWrapper.getDouble("legacy_knockback.extra_vertical", 0.1);
+        legacyKnockbackResistanceEnabled = configWrapper.getBoolean("legacy_knockback.enable_knockback_resistance", false);
+
+        notifyUpdate = configWrapper.getBoolean("notify_updates", true);
+        autoUpdate = configWrapper.getBoolean("auto_update", true);
+        combatTimer = configWrapper.getLong("runnable.combat_timer", 30L);
+        spikeThreshold = configWrapper.getLong("spike_threshold", 20L);
+        enableMessage = configWrapper.getString("messages.toggle.global.enable", "&aSuccessfully enabled KnockbackSync.");
+        disableMessage = configWrapper.getString("messages.toggle.global.disable", "&cSuccessfully disabled KnockbackSync.");
+        playerEnableMessage = configWrapper.getString("messages.toggle.player.enable", "&aSuccessfully enabled KnockbackSync for %player%.");
+        playerDisableMessage = configWrapper.getString("messages.toggle.player.disable", "&aSuccessfully &cdisabled &aKnockbackSync for %player%.");
+        playerIneligibleMessage = configWrapper.getString("messages.toggle.player.ineligible", "&c%player% is ineligible for KnockbackSync. If you believe this is in error, please contact your server administrators.");
+        playerDisconnectedWhileExecutingCommand = configWrapper.getString("messages.toggle.player.disconnected-while-executing-command", "&c%player% disconnected while executing command.");
+    }
+
+    public void updateConfig() {
+        ConfigWrapper oldConfig = getConfigWrapper();
+        long oldConfigVersion = oldConfig.getLong("config_version", 0);
+
+        if (oldConfigVersion < CONFIG_VERSION) {
+            // Backup old config with comments
+            File backupFile = new File(configFile.getParentFile(), "config-version-" + oldConfigVersion + ".yml");
+            try {
+                Files.move(configFile.toPath(), backupFile.toPath());
+                Base.INSTANCE.getLogger().info("Backed up old config to " + backupFile.getName());
+            } catch (IOException e) {
+                Base.INSTANCE.getLogger().warning("Failed to backup old config: " + e.getMessage());
+            }
+
+            // Store old values
+            Map<String, Object> oldValues = new HashMap<>(config);
+
+            // Create new config with default values
+            Base.INSTANCE.saveDefaultConfig();
+            reloadConfig();
+
+            // Transfer existing settings
+            ConfigWrapper newConfig = getConfigWrapper();
+            transferAllSettings(oldConfig, newConfig);
+
+            // Set new config version
+            newConfig.set("config_version", CONFIG_VERSION);
+
+            // Save updated config
+            saveConfig();
+
+            Base.INSTANCE.getLogger().info("Config updated to version " + CONFIG_VERSION);
+        }
+    }
+
+    private void transferAllSettings(ConfigWrapper oldConfig, ConfigWrapper newConfig) {
+        transferSettingsRecursive(oldConfig, newConfig, ".");
+    }
+
+    private void transferSettingsRecursive(ConfigWrapper oldConfig, ConfigWrapper newConfig, String currentPath) {
+        for (String key : oldConfig.getKeys(currentPath)) {
+            String fullPath = currentPath.isEmpty() || currentPath.equals(".") ? key : currentPath + "." + key;
+            if (newConfig.contains(fullPath)) {
+                Object value = oldConfig.get(fullPath);
+                if (value instanceof Map) {
+                    transferSettingsRecursive(oldConfig, newConfig, fullPath);
+                } else {
+                    newConfig.set(fullPath, value);
+                }
+            }
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/manager/PlayerDataManager.java

@@ -0,0 +1,51 @@
+package me.caseload.knockbacksync.manager;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.util.FloodgateUtil;
+import me.caseload.knockbacksync.util.GeyserUtil;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentHashMap;
+
+public class PlayerDataManager {
+
+    private static final Map<User, PlayerData> playerDataMap = new ConcurrentHashMap<>();
+
+    public static @Nullable PlayerData getPlayerData(@NotNull User user) {
+        return playerDataMap.get(user);
+    }
+
+    public static void addPlayerData(@NotNull User user, @NotNull PlatformPlayer platformPlayer) {
+        if (!shouldExempt(platformPlayer.getUUID())) {
+            PlayerData playerData = new PlayerData(user, platformPlayer);
+            playerDataMap.put(user, playerData);
+            Base.INSTANCE.getEventBus().registerListeners(playerData);
+        }
+    }
+
+    public static void removePlayerData(@NotNull User user) {
+        PlayerData playerData = playerDataMap.remove(user);
+        if (playerData != null)
+            Base.INSTANCE.getEventBus().unregisterListeners(playerData);
+    }
+
+    public static boolean containsPlayerData(@NotNull User user) {
+        return playerDataMap.containsKey(user);
+    }
+
+    public static boolean shouldExempt(@NotNull UUID uuid) {
+        // Geyser players don't have Java movement
+        return GeyserUtil.isGeyserPlayer(uuid)
+                // Floodgate is the authentication system for Geyser on servers that use Geyser as a proxy instead of installing it as a plugin directly on the server
+                || FloodgateUtil.isFloodgatePlayer(uuid)
+                // Geyser formatted player string
+                // This will never happen for Java players, as the first character in the 3rd group is always 4 (xxxxxxxx-xxxx-4xxx-xxxx-xxxxxxxxxxxx)
+                || uuid.toString().startsWith("00000000-0000-0000-0009");
+    }
+}

common/src/main/java/me/caseload/knockbacksync/permission/PermissionChecker.java

@@ -0,0 +1,12 @@
+package me.caseload.knockbacksync.permission;
+
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.sender.Sender;
+
+public interface PermissionChecker {
+    boolean hasPermission(Object nativeType, String s, boolean defaultIfUnset);
+
+    boolean hasPermission(Sender source, String s, boolean defaultIfUnset);
+
+    boolean hasPermission(PlatformPlayer platform, String s);
+}

common/src/main/java/me/caseload/knockbacksync/player/JitterCalculator.java

@@ -0,0 +1,58 @@
+package me.caseload.knockbacksync.player;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class JitterCalculator {
+    private final int SAMPLE_SIZE = 15;
+    private final Queue<Long> pings = new LinkedList<>();
+
+    public void addPing(long pingTime) {
+        pings.offer(pingTime);
+        if (pings.size() > SAMPLE_SIZE) {
+            pings.poll();
+        }
+    }
+
+    public double calculateJitter() {
+        if (pings.size() < 2) return 0;
+
+        List<Long> sortedPings = new ArrayList<>(pings);
+        Collections.sort(sortedPings);
+
+        // Calculate IQR
+        int q1Index = sortedPings.size() / 4;
+        int q3Index = q1Index * 3;
+        long q1 = sortedPings.get(q1Index);
+        long q3 = sortedPings.get(q3Index);
+        long iqr = q3 - q1;
+
+        // Filter outliers
+        double lowerBound = q1 - 1.5 * iqr;
+        double upperBound = q3 + 1.5 * iqr;
+        List<Long> filteredPings = sortedPings.stream()
+                .filter(p -> p >= lowerBound && p <= upperBound)
+                .collect(Collectors.toList());
+
+        // Calculate standard deviation
+        double mean = filteredPings.stream().mapToLong(Long::longValue).average().orElse(0);
+        double variance = filteredPings.stream()
+                .mapToDouble(p -> Math.pow(p - mean, 2))
+                .average().orElse(0);
+        double stdDev = Math.sqrt(variance);
+
+        // Calculate mean jitter
+        double meanJitter = 0;
+        Long prevPing = null;
+        for (Long ping : filteredPings) {
+            if (prevPing != null) {
+                meanJitter += Math.abs(ping - prevPing);
+            }
+            prevPing = ping;
+        }
+        meanJitter /= (filteredPings.size() - 1);
+
+        // You can return different jitter metrics based on your needs
+        return stdDev / 1_000_000.0; // or meanJitter, or both
+    }
+}

common/src/main/java/me/caseload/knockbacksync/player/PingStrategy.java

@@ -0,0 +1,6 @@
+package me.caseload.knockbacksync.player;
+
+public enum PingStrategy {
+    KEEPALIVE,
+    TRANSACTION
+}

common/src/main/java/me/caseload/knockbacksync/player/PlatformPlayer.java

@@ -0,0 +1,76 @@
+package me.caseload.knockbacksync.player;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.protocol.world.BoundingBox;
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.world.PlatformWorld;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.util.UUID;
+
+public interface PlatformPlayer {
+    UUID getUUID();
+
+    String getName();
+
+    double getX();
+
+    double getY();
+
+    double getZ();
+
+    float getPitch();
+
+    float getYaw();
+
+    boolean isOnGround();
+
+    int getPing();
+
+    boolean isGliding();
+
+    PlatformWorld getWorld();
+
+    Vector3d getLocation();
+
+    void sendMessage(@NotNull String s);
+
+    double getAttackCooldown();
+
+    boolean isSprinting();
+
+    int getMainHandKnockbackLevel();
+
+    /**
+     * Knockback enchant level used for legacy (1.8) knockback bonus calculation.
+     * Mirrors OldCombatMechanics: the main hand item, or the off hand item when the
+     * main hand is empty. Defaults to the main hand level for platforms that do not
+     * override it.
+     */
+    default int getWeaponKnockbackLevel() {
+        return getMainHandKnockbackLevel();
+    }
+
+    @Nullable Integer getNoDamageTicks();
+
+    void setVelocity(Vector3d adjustedVelocity);
+
+    Vector3d getVelocity();
+
+    double getJumpPower();
+
+    BoundingBox getBoundingBox();
+
+    /**
+     * If a player disconnects while we are running the constructor of a PlatformPlayer
+     * PacketEvents.getAPI().getPlayerManager().getUser(bukkitPlayer) may return null
+     * This will make the internal field null and thus this function may return null.
+     */
+    @Nullable User getUser();
+
+    void setClientBrand(String brand);
+
+    String getClientBrand();
+    // Add more methods as needed
+}

common/src/main/java/me/caseload/knockbacksync/player/PlayerData.java

@@ -0,0 +1,436 @@
+package me.caseload.knockbacksync.player;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.manager.player.PlayerManager;
+import com.github.retrooper.packetevents.manager.server.ServerVersion;
+import com.github.retrooper.packetevents.netty.channel.ChannelHelper;
+import com.github.retrooper.packetevents.protocol.ConnectionState;
+import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
+import com.github.retrooper.packetevents.protocol.world.BoundingBox;
+import com.github.retrooper.packetevents.util.Vector3d;
+import com.github.retrooper.packetevents.wrapper.PacketWrapper;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerKeepAlive;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerPing;
+import com.github.retrooper.packetevents.wrapper.play.server.WrapperPlayServerWindowConfirmation;
+import lombok.Getter;
+import lombok.Setter;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.command.subcommand.ToggleOffGroundSubcommand;
+import me.caseload.knockbacksync.event.KBSyncEventHandler;
+import me.caseload.knockbacksync.event.events.ConfigReloadEvent;
+import me.caseload.knockbacksync.event.events.ToggleOnOffEvent;
+import me.caseload.knockbacksync.manager.CombatManager;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.scheduler.AbstractTaskHandle;
+import me.caseload.knockbacksync.scheduler.NettyTaskHandle;
+import me.caseload.knockbacksync.util.MathUtil;
+import me.caseload.knockbacksync.util.data.Pair;
+import me.caseload.knockbacksync.world.PlatformWorld;
+import me.caseload.knockbacksync.world.raytrace.FluidHandling;
+import me.caseload.knockbacksync.world.raytrace.RayTraceResult;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+import java.lang.reflect.Field;
+import io.netty.channel.Channel;
+import java.util.*;
+import java.util.concurrent.ConcurrentLinkedQueue;
+import java.util.concurrent.TimeUnit;
+
+@Getter
+public class PlayerData {
+
+    // Please read the GitHub FAQ before adjusting.
+    private static final short MAIN_THREAD_TRANSACTION_ID = 31407;
+    private static final short NETTY_THREAD_TRANSACTION_ID = 31408;
+    public static final long PING_OFFSET = 25;
+
+    private static Field playerField;
+
+    public final Queue<Pair<Integer, Long>> transactionsSent = new ConcurrentLinkedQueue<>();
+    public final Queue<Pair<Long, Long>> keepaliveMap = new ConcurrentLinkedQueue<>();
+
+    static {
+        try {
+            switch (Base.INSTANCE.getPlatform()) {
+                case BUKKIT:
+                case FOLIA:
+                    Class<?> bukkitPlayerClass = Class.forName("me.caseload.knockbacksync.player.BukkitPlayer");
+                    playerField = bukkitPlayerClass.getDeclaredField("bukkitPlayer");
+                    break;
+                case FABRIC:
+                    Class<?> fabricPlayerClass = Class.forName("me.caseload.knockbacksync.player.FabricPlayer");
+                    playerField = fabricPlayerClass.getDeclaredField("fabricPlayer");
+                    break;
+                default:
+                    throw new IllegalStateException("Unexpected platform: " + Base.INSTANCE.getPlatform());
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        }
+        playerField.setAccessible(true); // May not be needed since it's already public
+    }
+
+    public final User user;
+    private final PlatformPlayer platformPlayer;
+    private final UUID uuid;
+    @NotNull private final Random random = new Random();
+    public long lastKeepAliveID = 0;
+    @Getter private final JitterCalculator jitterCalculator = new JitterCalculator();
+    @Setter private double jitter;
+    @Nullable private AbstractTaskHandle combatTask;
+    @NotNull private final Object combatTaskLock = new Object(); // Lock object for synchronization
+    @Nullable @Setter private Double ping, previousPing;
+    @Nullable @Setter private Double verticalVelocity;
+    @Nullable @Setter private Integer lastDamageTicks;
+    // Legacy (1.8) knockback computed at damage time, consumed by the next PlayerVelocityEvent.
+    // Guarded by a short expiry so a stale value never affects an unrelated velocity event.
+    @Nullable private Vector3d legacyKnockback;
+    private long legacyKnockbackExpiryNanos;
+    // True when the pending legacyKnockback is a fishing-rod (bobber-direction) vector supplied
+    // via the rod API rather than the melee formula. Lets the damage listener keep the rod vector
+    // instead of overwriting it with melee, while still latency-syncing it. See api.KnockbackSyncRodApi.
+    private boolean legacyKnockbackIsRod;
+    @Setter private double gravityAttribute = 0.08;
+    @Setter private double knockbackResistanceAttribute = 0.0;
+    public PingStrategy pingStrategy; // this is currently shared between all instances, but can be made per-player later
+
+    public PlayerData(User user, PlatformPlayer platformPlayer) {
+        this.uuid = platformPlayer.getUUID();
+        this.user = user;
+        this.platformPlayer = platformPlayer;
+        this.pingStrategy = loadPingStrategy(Base.INSTANCE.getConfigManager());
+    }
+
+    /**
+     * Stores the legacy (1.8) knockback to apply on the next PlayerVelocityEvent.
+     * Expires shortly after so it can never be applied to an unrelated velocity event
+     * (explosions, other plugins, etc.) if the expected velocity event never fires.
+     */
+    public void setLegacyKnockback(@Nullable Vector3d legacyKnockback) {
+        this.legacyKnockback = legacyKnockback;
+        this.legacyKnockbackIsRod = false;
+        // 100ms window: damage and the resulting velocity event fire in the same tick.
+        this.legacyKnockbackExpiryNanos = System.nanoTime() + 100_000_000L;
+    }
+
+    /**
+     * Stores a fishing-rod (bobber-direction) knockback to apply + latency-sync on the next
+     * PlayerVelocityEvent, flagged so the damage listener keeps it instead of overwriting it with
+     * the melee formula. Must be set immediately before the rod's damage tick. See
+     * {@code api.KnockbackSyncRodApi}.
+     */
+    public void setRodKnockback(@NotNull Vector3d rodKnockback) {
+        this.legacyKnockback = rodKnockback;
+        this.legacyKnockbackIsRod = true;
+        this.legacyKnockbackExpiryNanos = System.nanoTime() + 100_000_000L;
+    }
+
+    /**
+     * @return true if an unexpired fishing-rod knockback is pending (so the damage listener must
+     * not overwrite it with melee knockback).
+     */
+    public boolean isRodKnockbackPending() {
+        return peekLegacyKnockback() != null && legacyKnockbackIsRod;
+    }
+
+    /**
+     * @return the pending legacy knockback if present and not expired, otherwise {@code null}.
+     */
+    @Nullable
+    public Vector3d peekLegacyKnockback() {
+        if (legacyKnockback == null) return null;
+        if (System.nanoTime() > legacyKnockbackExpiryNanos) {
+            legacyKnockback = null;
+            legacyKnockbackIsRod = false;
+            return null;
+        }
+        return legacyKnockback;
+    }
+
+    /**
+     * Returns and clears the pending legacy knockback (if present and not expired).
+     */
+    @Nullable
+    public Vector3d consumeLegacyKnockback() {
+        Vector3d v = peekLegacyKnockback();
+        legacyKnockback = null;
+        legacyKnockbackIsRod = false;
+        return v;
+    }
+
+    public double getNotNullPing() {
+        return ping != null ? ping : platformPlayer.getPing();
+    }
+
+    public double getNotNullPreviousPing() {
+        return previousPing != null ? previousPing : platformPlayer.getPing();
+    }
+
+    /**
+     * Calculates the player's ping with compensation for lag spikes.
+     * A hardcoded offset is applied for several reasons,
+     * read the GitHub FAQ before adjusting.
+     *
+     * @return The compensated ping, with a minimum of 1.
+     */
+    public double getCompensatedPing() {
+        double ping = getNotNullPing();
+        double previousPing = getNotNullPreviousPing();
+        double spikeCompensatedPing = (ping - previousPing > Base.INSTANCE.getConfigManager().getSpikeThreshold()) ? previousPing : ping;
+
+        return Math.max(1, spikeCompensatedPing - PING_OFFSET);
+    }
+
+    public int getCompensatedTicks() {
+        return (int) Math.ceil(getCompensatedPing() * Base.INSTANCE.getTickRate() / 1000); // Multiply ping by seconds per tick
+    }
+
+    public int getTicks() {
+        return (int) Math.ceil(getNotNullPing() * Base.INSTANCE.getTickRate() / 1000); // Multiply ping by seconds per tick
+    }
+
+    public boolean isSpike() {
+        return (getNotNullPing() - getNotNullPreviousPing()) > Base.INSTANCE.getConfigManager().getSpikeThreshold();
+    }
+
+    public void sendPing(boolean async) {
+        if (user == null || user.getEncoderState() != ConnectionState.PLAY) return;
+
+       switch (pingStrategy) {
+           case KEEPALIVE:
+               long keepAliveID = async ? NETTY_THREAD_TRANSACTION_ID : MAIN_THREAD_TRANSACTION_ID;
+               if (async) {
+                   ChannelHelper.runInEventLoop(user.getChannel(), () -> {
+                       // We call sendPacket instead of writePacket because it flushes immediately
+                       // Making our time measurement more accurate since we don't call, System.nanoTime(), wait until flush
+                       // And then actually send packet
+                       user.sendPacket(new WrapperPlayServerKeepAlive(keepAliveID));
+                   });
+               } else {
+                   user.sendPacket(new WrapperPlayServerKeepAlive(keepAliveID));
+               }
+               break;
+           case TRANSACTION:
+               PacketWrapper<?> packet;
+               short pingTransactionID = async ? NETTY_THREAD_TRANSACTION_ID : MAIN_THREAD_TRANSACTION_ID;
+               if (PacketEvents.getAPI().getServerManager().getVersion().isNewerThanOrEquals(ServerVersion.V_1_17)) {
+                   packet = new WrapperPlayServerPing(pingTransactionID);
+               } else {
+                   packet = new WrapperPlayServerWindowConfirmation((byte) 0, pingTransactionID, false);
+               }
+
+               // sendPacket (write + flush) rather than writePacket: an unflushed write sits in the channel until the next flush and inflates the measured ping.
+               if (async) {
+                   ChannelHelper.runInEventLoop(user.getChannel(), () -> {
+                       user.sendPacket(packet);
+                   });
+               } else {
+                   user.sendPacket(packet);
+               }
+               break;
+       }
+    }
+
+    /**
+     * Determines if the Player is on the ground clientside, but not serverside
+     * <p>
+     * Returns <code>ping ≥ (tMax + tFall)</code> and <code>gDist ≤ 1.3</code>
+     * <p>
+     * Where:
+     * <ul>
+     *   <li><code>ping</code>: Estimated latency</li>
+     *   <li><code>tMax</code>: Time to reach maximum upward velocity</li>
+     *   <li><code>tFall</code>: Time to fall to the ground</li>
+     *   <li><code>gDist</code>: Distance to the ground</li>
+     * </ul>
+     *
+     * @param verticalVelocity The Player's current vertical velocity.
+     * @return <code>true</code> if the Player is on the ground; <code>false</code> otherwise.
+     */
+    public boolean isOnGroundClientSide(double verticalVelocity, double distanceToGround) {
+        int tMax = verticalVelocity > 0 ? MathUtil.calculateTimeToMaxVelocity(verticalVelocity, gravityAttribute) : 0;
+        if (tMax == -1)
+            return false; // reached the max tick limit, not safe to predict
+
+        double mH = verticalVelocity > 0 ? MathUtil.calculateDistanceTraveled(verticalVelocity, tMax, gravityAttribute) : 0;
+        int tFall = MathUtil.calculateFallTime(verticalVelocity, mH + distanceToGround, gravityAttribute);
+
+        if (tFall == -1)
+            return false; // reached the max tick limit, not safe to predict
+
+        return (tMax + tFall) - getCompensatedTicks() <= 0 && distanceToGround <= 1.3;
+    }
+
+    /**
+     * Gets whether or not offGroundSynchronization is enabled for the player.
+     * @return <code>true</code> if enabled; <code>false</code> otherwise.
+     */
+    public boolean isOffGroundSyncEnabled() {
+        // TODO, per-player offground sync toggles?
+        return ToggleOffGroundSubcommand.offGroundSyncEnabled;
+    }
+
+    /**
+     * Gets the compensated off-ground velocity.
+     * This is used to make knockback feel more accurate off-ground.
+     *
+     * @return Compensated Y axis velocity
+     */
+    public double getCompensatedOffGroundVelocity() {
+        return MathUtil.getCompensatedVerticalVelocity(platformPlayer.getVelocity().getY(), getGravityAttribute(), getTicks());
+    }
+
+    /**
+     * Ray traces from each corner of the player's bounding box to the ground,
+     * returning the smallest distance, with a maximum limit of 5 blocks.
+     *
+     * @return The distance to the ground in blocks
+     */
+    public double getDistanceToGround() {
+        double collisionDist = 5;
+
+        PlatformWorld world = platformPlayer.getWorld();
+
+        for (Vector3d corner : getBBCorners()) {
+            RayTraceResult result = world.rayTraceBlocks(corner, new Vector3d(0, -1, 0), 5, FluidHandling.NONE, true);
+
+            if (result == null || result.getHitBlock() == null)
+                continue;
+
+            collisionDist = Math.min(collisionDist, corner.getY() - result.getHitBlockPosition().getY());
+        }
+
+        return collisionDist - 1;
+    }
+
+    /**
+     * Gets the corners of the Player's bounding box.
+     *
+     * @return An array of locations representing the corners of the bounding box.
+     */
+    private Vector3d[] getBBCorners() {
+        BoundingBox boundingBox = platformPlayer.getBoundingBox();
+        Vector3d location = platformPlayer.getLocation();
+
+        double adjustment = 0.01; // To ensure the bounding box isn't clipping inside a wall
+
+        return new Vector3d[] {
+                new Vector3d(boundingBox.getMinX() + adjustment, location.getY(), boundingBox.getMinZ() + adjustment),
+                new Vector3d(boundingBox.getMinX() + adjustment, location.getY(), boundingBox.getMaxZ() - adjustment),
+                new Vector3d(boundingBox.getMaxX() - adjustment, location.getY(), boundingBox.getMinZ() + adjustment),
+                new Vector3d(boundingBox.getMaxX() - adjustment, location.getY(), boundingBox.getMaxZ() - adjustment)
+        };
+    }
+
+    /**
+     * Calculates the positive vertical velocity.
+     * This is used to switch falling knockback to rising knockback.
+     *
+     * @param attacker The player who is attacking.
+     * @return The calculated positive vertical velocity, consistent with vanilla behavior.
+     */
+    public double calculateVerticalVelocity(PlatformPlayer attacker) {
+        double yAxis = attacker.getAttackCooldown() > 0.848 ? 0.4 : 0.36080000519752503;
+
+        if (!attacker.isSprinting()) {
+            yAxis = 0.36080000519752503;
+            double resistanceFactor = 0.04000000119 * knockbackResistanceAttribute * 10;
+            yAxis -= resistanceFactor;
+        }
+
+        // vertical velocity is always 0.4 when you have knockback level higher than 0
+        if (attacker.getMainHandKnockbackLevel() > 0)
+            yAxis = 0.4;
+
+        return yAxis;
+    }
+
+    public void updateCombat() {
+        Channel channel = (Channel) user.getChannel();
+        channel.eventLoop().execute(() -> {
+            if (combatTask != null) {
+                combatTask.cancel();
+            }
+            combatTask = newCombatTask(channel);
+            CombatManager.addPlayer(user);
+        });
+    }
+
+    /**
+     * Cancels the combatTask quit task. This prevents quitCombat() from being called later against a new combat task
+     * Or against a player that has disconnected already
+     * @param async Whether we are already in the players netty thread
+     */
+    public void quitCombat(boolean async) {
+        Channel channel = (Channel) user.getChannel();
+        Runnable runnable = () -> {
+            if (combatTask != null) {
+                combatTask.cancel();
+                combatTask = null;
+            }
+            CombatManager.removePlayer(user);
+        };
+        if (async) {
+            channel.eventLoop().execute(runnable);
+        } else {
+            runnable.run();
+        }
+    }
+
+    @NotNull
+    private AbstractTaskHandle newCombatTask(Channel channel) {
+        return new NettyTaskHandle(channel.eventLoop().schedule(() -> quitCombat(false), convertTicksToMilliseconds(Base.INSTANCE.getConfigManager().getCombatTimer()), TimeUnit.MILLISECONDS));
+    }
+
+    public ClientVersion getClientVersion() {
+        if (user == null)
+            return ClientVersion.UNKNOWN;
+        ClientVersion ver = user.getClientVersion();
+        if (ver == null) {
+            // If temporarily null, assume server version...
+            return ClientVersion.getById(PacketEvents.getAPI().getServerManager().getVersion().getProtocolVersion());
+        }
+        return ver;
+    }
+
+    public long getKeepAliveSendTime() {
+        return lastKeepAliveID;
+    }
+
+    public boolean didWeSendThatPacket(long receivedId) {
+        return receivedId == NETTY_THREAD_TRANSACTION_ID || receivedId == MAIN_THREAD_TRANSACTION_ID;
+    }
+
+    @KBSyncEventHandler
+    public void onToggledEvent(ToggleOnOffEvent event) {
+        if (!event.getStatus()) {
+            transactionsSent.clear();
+            keepaliveMap.clear();
+        }
+    }
+
+    @KBSyncEventHandler
+    public void onConfigReloadEvent(ConfigReloadEvent event) {
+        this.pingStrategy = loadPingStrategy(event.getConfigManager());
+    }
+
+    private PingStrategy loadPingStrategy(ConfigManager  configManager) {
+        // Default PING: vanilla ignores unintercepted pong echoes, while unintercepted keepalive echoes kick ("Timed out") on 1.20.2+.
+        String pingStrategy = configManager.getConfigWrapper().getString("ping_strategy", "PING");
+        switch (pingStrategy) {
+            case "KEEPALIVE":
+                return PingStrategy.KEEPALIVE;
+            case "PING":
+            case "TRANSACTION":
+                return PingStrategy.TRANSACTION;
+            default:
+                throw new IllegalStateException("Unknown ping_strategy: " + pingStrategy);
+        }
+    }
+
+    private long convertTicksToMilliseconds(long ticks) {
+        return ticks * 50;
+    }
+}

common/src/main/java/me/caseload/knockbacksync/runnable/PingRunnable.java

@@ -0,0 +1,24 @@
+package me.caseload.knockbacksync.runnable;
+
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.CombatManager;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlayerData;
+
+import java.util.UUID;
+
+public class PingRunnable implements Runnable {
+
+    @Override
+    public void run() {
+        if (!Base.INSTANCE.getConfigManager().isToggled())
+            return;
+
+        for (User user : CombatManager.getPlayers()) {
+            PlayerData playerData = PlayerDataManager.getPlayerData(user);
+            if (playerData != null)
+                playerData.sendPing(true);
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/scheduler/AbstractTaskHandle.java

@@ -0,0 +1,8 @@
+package me.caseload.knockbacksync.scheduler;
+
+public interface AbstractTaskHandle {
+
+    boolean getCancelled();
+
+    void cancel();
+}

common/src/main/java/me/caseload/knockbacksync/scheduler/NettyTaskHandle.java

@@ -0,0 +1,22 @@
+package me.caseload.knockbacksync.scheduler;
+
+import io.netty.util.concurrent.ScheduledFuture;
+
+public class NettyTaskHandle implements AbstractTaskHandle {
+
+    private final ScheduledFuture scheduledFuture;
+
+    public NettyTaskHandle(ScheduledFuture<?> scheduledFuture) {
+        this.scheduledFuture = scheduledFuture;
+    }
+
+    @Override
+    public boolean getCancelled() {
+        return scheduledFuture.isCancelled();
+    }
+
+    @Override
+    public void cancel() {
+        scheduledFuture.cancel(true);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/scheduler/SchedulerAdapter.java

@@ -0,0 +1,17 @@
+package me.caseload.knockbacksync.scheduler;
+
+public interface SchedulerAdapter {
+    AbstractTaskHandle runTask(Runnable task);
+
+    AbstractTaskHandle runTaskAsynchronously(Runnable task);
+
+    AbstractTaskHandle runTaskLater(Runnable task, long delayTicks);
+
+    AbstractTaskHandle runTaskTimer(Runnable task, long delayTicks, long periodTicks);
+
+    AbstractTaskHandle runTaskLaterAsynchronously(Runnable task, long delay);
+
+    AbstractTaskHandle runTaskTimerAsynchronously(Runnable task, long delay, long period);
+
+    void shutdown();
+}

common/src/main/java/me/caseload/knockbacksync/sender/AbstractSender.java

@@ -0,0 +1,93 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.Base;
+
+import java.util.UUID;
+
+/**
+ * Simple implementation of {@link Sender} using a {@link SenderFactory}
+ *
+ * @param <T> the command sender type
+ */
+public final class AbstractSender<T> implements Sender {
+    private final Base plugin;
+    private final SenderFactory<?, T> factory;
+    private final T sender;
+
+    private final UUID uniqueId;
+    private final String name;
+    private final boolean isConsole;
+
+    AbstractSender(Base plugin, SenderFactory<?, T> factory, T sender) {
+        this.plugin = plugin;
+        this.factory = factory;
+        this.sender = sender;
+        this.uniqueId = factory.getUniqueId(this.sender);
+        this.name = factory.getName(this.sender);
+        this.isConsole = this.factory.isConsole(this.sender);
+    }
+
+    @Override
+    public Base getPlugin() {
+        return this.plugin;
+    }
+
+    @Override
+    public UUID getUniqueId() {
+        return this.uniqueId;
+    }
+
+    @Override
+    public String getName() {
+        return this.name;
+    }
+
+    @Override
+    public void sendMessage(String message) {
+        this.factory.sendMessage(this.sender, message);
+    }
+
+    @Override
+    public boolean hasPermission(String permission) {
+        return isConsole() || this.factory.hasPermission(this.sender, permission);
+    }
+
+    @Override
+    public boolean hasPermission(String permission, boolean defaultIfUnset) {
+        return isConsole() || this.factory.hasPermission(this.sender, permission, defaultIfUnset);
+    }
+
+    @Override
+    public void performCommand(String commandLine) {
+        this.factory.performCommand(this.sender, commandLine);
+    }
+
+    @Override
+    public boolean isConsole() {
+        return this.isConsole;
+    }
+
+    @Override
+    public boolean isValid() {
+        return true;
+//        return isConsole() || this.plugin.getBootstrap().isPlayerOnline(this.uniqueId);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (o == this) return true;
+        if (!(o instanceof AbstractSender)) return false;
+        final AbstractSender<?> that = (AbstractSender<?>) o;
+        return this.getUniqueId().equals(that.getUniqueId());
+    }
+
+    @Override
+    public int hashCode() {
+        return this.uniqueId.hashCode();
+    }
+
+    @Override
+    public T getSender() {
+        return sender;
+    }
+}

common/src/main/java/me/caseload/knockbacksync/sender/Sender.java

@@ -0,0 +1,92 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.Base;
+
+import java.util.UUID;
+
+/**
+ * Wrapper interface to represent a CommandSender/CommandSource within the common command implementations.
+ */
+public interface Sender {
+
+    /**
+     * The uuid used by the console sender.
+     */
+    UUID CONSOLE_UUID = new UUID(0, 0); // 00000000-0000-0000-0000-000000000000
+    /**
+     * The name used by the console sender.
+     */
+    String CONSOLE_NAME = "Console";
+
+    /**
+     * Gets the plugin instance the sender is from.
+     *
+     * @return the plugin
+     */
+    Base getPlugin();
+
+    /**
+     * Gets the sender's username
+     *
+     * @return a friendly username for the sender
+     */
+    String getName();
+
+    /**
+     * Gets a string representing the senders username, and their current location
+     * within the network.
+     *
+     * @return a friendly identifier for the sender
+     */
+
+    /**
+     * Gets the sender's unique id.
+     *
+     * <p>See {@link #CONSOLE_UUID} for the console's UUID representation.</p>
+     *
+     * @return the sender's uuid
+     */
+    UUID getUniqueId();
+
+    /**
+     * Send a json message to the Sender.
+     *
+     * @param message the message to send.
+     */
+    void sendMessage(String message);
+
+    /**
+     * Check if the Sender has a permission.
+     *
+     * @param permission the permission to check for
+     * @return true if the sender has the permission
+     */
+    boolean hasPermission(String permission);
+
+    boolean hasPermission(String permission, boolean defaultIfUnset);
+
+    /**
+     * Makes the sender perform a command.
+     *
+     * @param commandLine the command
+     */
+    void performCommand(String commandLine);
+
+    /**
+     * Gets whether this sender is the console
+     *
+     * @return if the sender is the console
+     */
+    boolean isConsole();
+
+    /**
+     * Gets whether this sender is still valid & receiving messages.
+     *
+     * @return if this sender is valid
+     */
+    default boolean isValid() {
+        return true;
+    }
+
+    Object getSender();
+}

common/src/main/java/me/caseload/knockbacksync/sender/SenderFactory.java

@@ -0,0 +1,53 @@
+package me.caseload.knockbacksync.sender;
+
+import me.caseload.knockbacksync.Base;
+
+import java.util.Objects;
+import java.util.UUID;
+
+/**
+ * Factory class to make a thread-safe sender instance
+ *
+ * @param <P> the plugin type
+ * @param <T> the command sender type
+ */
+public abstract class SenderFactory<P extends Base, T> implements AutoCloseable {
+    private final P plugin;
+
+    public SenderFactory(P plugin) {
+        this.plugin = plugin;
+    }
+
+    protected P getPlugin() {
+        return this.plugin;
+    }
+
+    protected abstract UUID getUniqueId(T sender);
+
+    protected abstract String getName(T sender);
+
+    protected abstract void sendMessage(T sender, String message);
+
+    protected abstract boolean hasPermission(T sender, String node);
+
+    protected abstract boolean hasPermission(T sender, String node, boolean defaultIfUnset);
+
+    protected abstract void performCommand(T sender, String command);
+
+    protected abstract boolean isConsole(T sender);
+
+    protected boolean shouldSplitNewlines(T sender) {
+        return isConsole(sender);
+    }
+
+    public final Sender wrap(T sender) {
+        Objects.requireNonNull(sender, "sender");
+        return new AbstractSender<>(this.plugin, this, sender);
+    }
+
+    @SuppressWarnings("unchecked")
+    public final T unwrap(Sender sender) {
+        Objects.requireNonNull(sender, "sender");
+        return (T) sender.getSender();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/AdvancedBarChart.java

@@ -0,0 +1,44 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+public class AdvancedBarChart extends CustomChart {
+
+    private final Callable<Map<String, int[]>> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public AdvancedBarChart(String chartId, Callable<Map<String, int[]>> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
+        Map<String, int[]> map = callable.call();
+        if (map == null || map.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        boolean allSkipped = true;
+        for (Map.Entry<String, int[]> entry : map.entrySet()) {
+            if (entry.getValue().length == 0) {
+                // Skip this invalid
+                continue;
+            }
+            allSkipped = false;
+            valuesBuilder.appendField(entry.getKey(), entry.getValue());
+        }
+        if (allSkipped) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/AdvancedPie.java

@@ -0,0 +1,44 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+public class AdvancedPie extends CustomChart {
+
+    private final Callable<Map<String, Integer>> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public AdvancedPie(String chartId, Callable<Map<String, Integer>> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
+        Map<String, Integer> map = callable.call();
+        if (map == null || map.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        boolean allSkipped = true;
+        for (Map.Entry<String, Integer> entry : map.entrySet()) {
+            if (entry.getValue() == 0) {
+                // Skip this invalid
+                continue;
+            }
+            allSkipped = false;
+            valuesBuilder.appendField(entry.getKey(), entry.getValue());
+        }
+        if (allSkipped) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/CustomChart.java

@@ -0,0 +1,37 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.function.BiConsumer;
+
+public abstract class CustomChart {
+
+    private final String chartId;
+
+    protected CustomChart(String chartId) {
+        if (chartId == null) {
+            throw new IllegalArgumentException("chartId must not be null");
+        }
+        this.chartId = chartId;
+    }
+
+    public JsonObjectBuilder.JsonObject getRequestJsonObject(
+            BiConsumer<String, Throwable> errorLogger, boolean logErrors) {
+        JsonObjectBuilder builder = new JsonObjectBuilder();
+        builder.appendField("chartId", chartId);
+        try {
+            JsonObjectBuilder.JsonObject data = getChartData();
+            if (data == null) {
+                // If the data is null we don't send the chart.
+                return null;
+            }
+            builder.appendField("data", data);
+        } catch (Throwable t) {
+            if (logErrors) {
+                errorLogger.accept("Failed to get data for custom chart with id " + chartId, t);
+            }
+            return null;
+        }
+        return builder.build();
+    }
+
+    protected abstract JsonObjectBuilder.JsonObject getChartData() throws Exception;
+}

common/src/main/java/me/caseload/knockbacksync/stats/DrilldownPie.java

@@ -0,0 +1,48 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+public class DrilldownPie extends CustomChart {
+
+    private final Callable<Map<String, Map<String, Integer>>> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public DrilldownPie(String chartId, Callable<Map<String, Map<String, Integer>>> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    public JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
+        Map<String, Map<String, Integer>> map = callable.call();
+        if (map == null || map.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        boolean reallyAllSkipped = true;
+        for (Map.Entry<String, Map<String, Integer>> entryValues : map.entrySet()) {
+            JsonObjectBuilder valueBuilder = new JsonObjectBuilder();
+            boolean allSkipped = true;
+            for (Map.Entry<String, Integer> valueEntry : map.get(entryValues.getKey()).entrySet()) {
+                valueBuilder.appendField(valueEntry.getKey(), valueEntry.getValue());
+                allSkipped = false;
+            }
+            if (!allSkipped) {
+                reallyAllSkipped = false;
+                valuesBuilder.appendField(entryValues.getKey(), valueBuilder.build());
+            }
+        }
+        if (reallyAllSkipped) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/JsonObjectBuilder.java

@@ -0,0 +1,210 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Arrays;
+import java.util.stream.Collectors;
+
+/**
+ * An extremely simple JSON builder.
+ *
+ * <p>While this class is neither feature-rich nor the most performant one, it's sufficient enough
+ * for its use-case.
+ */
+public class JsonObjectBuilder {
+
+    private StringBuilder builder = new StringBuilder();
+
+    private boolean hasAtLeastOneField = false;
+
+    public JsonObjectBuilder() {
+        builder.append("{");
+    }
+
+    /**
+     * Escapes the given string like stated in https://www.ietf.org/rfc/rfc4627.txt.
+     *
+     * <p>This method escapes only the necessary characters '"', '\'. and '\u0000' - '\u001F'.
+     * Compact escapes are not used (e.g., '\n' is escaped as "\u000a" and not as "\n").
+     *
+     * @param value The value to escape.
+     * @return The escaped value.
+     */
+    private static String escape(String value) {
+        final StringBuilder builder = new StringBuilder();
+        for (int i = 0; i < value.length(); i++) {
+            char c = value.charAt(i);
+            if (c == '"') {
+                builder.append("\\\"");
+            } else if (c == '\\') {
+                builder.append("\\\\");
+            } else if (c <= '\u000F') {
+                builder.append("\\u000").append(Integer.toHexString(c));
+            } else if (c <= '\u001F') {
+                builder.append("\\u00").append(Integer.toHexString(c));
+            } else {
+                builder.append(c);
+            }
+        }
+        return builder.toString();
+    }
+
+    /**
+     * Appends a null field to the JSON.
+     *
+     * @param key The key of the field.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendNull(String key) {
+        appendFieldUnescaped(key, "null");
+        return this;
+    }
+
+    /**
+     * Appends a string field to the JSON.
+     *
+     * @param key   The key of the field.
+     * @param value The value of the field.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, String value) {
+        if (value == null) {
+            throw new IllegalArgumentException("JSON value must not be null");
+        }
+        appendFieldUnescaped(key, "\"" + escape(value) + "\"");
+        return this;
+    }
+
+    /**
+     * Appends an integer field to the JSON.
+     *
+     * @param key   The key of the field.
+     * @param value The value of the field.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, int value) {
+        appendFieldUnescaped(key, String.valueOf(value));
+        return this;
+    }
+
+    /**
+     * Appends an object to the JSON.
+     *
+     * @param key    The key of the field.
+     * @param object The object.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, JsonObject object) {
+        if (object == null) {
+            throw new IllegalArgumentException("JSON object must not be null");
+        }
+        appendFieldUnescaped(key, object.toString());
+        return this;
+    }
+
+    /**
+     * Appends a string array to the JSON.
+     *
+     * @param key    The key of the field.
+     * @param values The string array.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, String[] values) {
+        if (values == null) {
+            throw new IllegalArgumentException("JSON values must not be null");
+        }
+        String escapedValues =
+                Arrays.stream(values)
+                        .map(value -> "\"" + escape(value) + "\"")
+                        .collect(Collectors.joining(","));
+        appendFieldUnescaped(key, "[" + escapedValues + "]");
+        return this;
+    }
+
+    /**
+     * Appends an integer array to the JSON.
+     *
+     * @param key    The key of the field.
+     * @param values The integer array.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, int[] values) {
+        if (values == null) {
+            throw new IllegalArgumentException("JSON values must not be null");
+        }
+        String escapedValues =
+                Arrays.stream(values).mapToObj(String::valueOf).collect(Collectors.joining(","));
+        appendFieldUnescaped(key, "[" + escapedValues + "]");
+        return this;
+    }
+
+    /**
+     * Appends an object array to the JSON.
+     *
+     * @param key    The key of the field.
+     * @param values The integer array.
+     * @return A reference to this object.
+     */
+    public JsonObjectBuilder appendField(String key, JsonObject[] values) {
+        if (values == null) {
+            throw new IllegalArgumentException("JSON values must not be null");
+        }
+        String escapedValues =
+                Arrays.stream(values).map(JsonObject::toString).collect(Collectors.joining(","));
+        appendFieldUnescaped(key, "[" + escapedValues + "]");
+        return this;
+    }
+
+    /**
+     * Appends a field to the object.
+     *
+     * @param key          The key of the field.
+     * @param escapedValue The escaped value of the field.
+     */
+    private void appendFieldUnescaped(String key, String escapedValue) {
+        if (builder == null) {
+            throw new IllegalStateException("JSON has already been built");
+        }
+        if (key == null) {
+            throw new IllegalArgumentException("JSON key must not be null");
+        }
+        if (hasAtLeastOneField) {
+            builder.append(",");
+        }
+        builder.append("\"").append(escape(key)).append("\":").append(escapedValue);
+        hasAtLeastOneField = true;
+    }
+
+    /**
+     * Builds the JSON string and invalidates this builder.
+     *
+     * @return The built JSON string.
+     */
+    public JsonObject build() {
+        if (builder == null) {
+            throw new IllegalStateException("JSON has already been built");
+        }
+        JsonObject object = new JsonObject(builder.append("}").toString());
+        builder = null;
+        return object;
+    }
+
+    /**
+     * A super simple representation of a JSON object.
+     *
+     * <p>This class only exists to make methods of the {@link JsonObjectBuilder} type-safe and not
+     * allow a raw string inputs for methods like {@link JsonObjectBuilder#appendField(String,
+     * JsonObject)}.
+     */
+    public static class JsonObject {
+
+        private final String value;
+
+        private JsonObject(String value) {
+            this.value = value;
+        }
+
+        @Override
+        public String toString() {
+            return value;
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/MultiLineChart.java

@@ -0,0 +1,44 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+public class MultiLineChart extends CustomChart {
+
+    private final Callable<Map<String, Integer>> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public MultiLineChart(String chartId, Callable<Map<String, Integer>> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
+        Map<String, Integer> map = callable.call();
+        if (map == null || map.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        boolean allSkipped = true;
+        for (Map.Entry<String, Integer> entry : map.entrySet()) {
+            if (entry.getValue() == 0) {
+                // Skip this invalid
+                continue;
+            }
+            allSkipped = false;
+            valuesBuilder.appendField(entry.getKey(), entry.getValue());
+        }
+        if (allSkipped) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/SimpleBarChart.java

@@ -0,0 +1,34 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.Map;
+import java.util.concurrent.Callable;
+
+public class SimpleBarChart extends CustomChart {
+
+    private final Callable<Map<String, Integer>> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public SimpleBarChart(String chartId, Callable<Map<String, Integer>> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        JsonObjectBuilder valuesBuilder = new JsonObjectBuilder();
+        Map<String, Integer> map = callable.call();
+        if (map == null || map.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        for (Map.Entry<String, Integer> entry : map.entrySet()) {
+            valuesBuilder.appendField(entry.getKey(), new int[]{entry.getValue()});
+        }
+        return new JsonObjectBuilder().appendField("values", valuesBuilder.build()).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/SimplePie.java

@@ -0,0 +1,29 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.concurrent.Callable;
+
+public class SimplePie extends CustomChart {
+
+    private final Callable<String> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public SimplePie(String chartId, Callable<String> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        String value = callable.call();
+        if (value == null || value.isEmpty()) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("value", value).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/SingleLineChart.java

@@ -0,0 +1,29 @@
+package me.caseload.knockbacksync.stats;
+
+import java.util.concurrent.Callable;
+
+public class SingleLineChart extends CustomChart {
+
+    private final Callable<Integer> callable;
+
+    /**
+     * Class constructor.
+     *
+     * @param chartId  The id of the chart.
+     * @param callable The callable which is used to request the chart data.
+     */
+    public SingleLineChart(String chartId, Callable<Integer> callable) {
+        super(chartId);
+        this.callable = callable;
+    }
+
+    @Override
+    protected JsonObjectBuilder.JsonObject getChartData() throws Exception {
+        int value = callable.call();
+        if (value == 0) {
+            // Null = skip the chart
+            return null;
+        }
+        return new JsonObjectBuilder().appendField("value", value).build();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/BuildTypePie.java

@@ -1,30 +1,25 @@
-package me.caseload.knockbacksync.stats;
+package me.caseload.knockbacksync.stats.custom;
 
 import com.google.gson.JsonObject;
 import com.google.gson.JsonParser;
-import me.caseload.knockbacksync.KnockbackSync;
-import org.bstats.charts.SimplePie;
-import org.bukkit.Bukkit;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.common.BuildConfig;
+import me.caseload.knockbacksync.stats.SimplePie;
 import org.kohsuke.github.GHAsset;
 import org.kohsuke.github.GHRelease;
 import org.kohsuke.github.GitHub;
 
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
-import java.io.InputStream;
+import java.io.*;
 import java.net.URL;
-import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.nio.file.Paths;
-import java.security.MessageDigest;
 import java.util.List;
 
 public class BuildTypePie extends SimplePie {
 
     private static final String RELEASES_FILE = "releases.txt";
     private static final String DEV_BUILDS_FILE = "dev-builds.txt";
-    private static final File dataFolder = KnockbackSync.INSTANCE.getDataFolder();
+    private static final File dataFolder = Base.INSTANCE.getDataFolder();
     private static String cachedBuildType = null;
 
     public BuildTypePie() {
@@ -40,7 +35,7 @@ public class BuildTypePie extends SimplePie {
 
     private static String calculateBuildType() {
         try {
-            String currentHash = getPluginJarHash();
+            String currentHash = Base.INSTANCE.getPluginJarHashProvider().getPluginJarHash();
             downloadBuildFiles();
 
             if (isHashInFile(currentHash, new File(dataFolder, RELEASES_FILE))) {
@@ -58,23 +53,26 @@ public class BuildTypePie extends SimplePie {
 
     private static void downloadBuildFiles() throws IOException {
         GitHub gitHub = GitHub.connectAnonymously();
-        GHRelease latestRelease = gitHub.getRepository("Axionize/knockback-sync")
+        GHRelease latestRelease = gitHub.getRepository(BuildConfig.GITHUB_REPO)
                 .getLatestRelease();
         List<GHAsset> assets = latestRelease.listAssets().toList();
         for (GHAsset asset : assets) {
             if (asset.getName().equals(RELEASES_FILE) || asset.getName().equals(DEV_BUILDS_FILE)) {
-                KnockbackSync.INSTANCE.getLogger().info("Downloading: " + asset.getName());
+                Base.INSTANCE.getLogger().info("Downloading: " + asset.getName());
 
                 String jsonContent = readStringFromURL(asset.getUrl().toString());
                 JsonObject jsonObject = JsonParser.parseString(jsonContent).getAsJsonObject();
                 String downloadUrl = jsonObject.get("browser_download_url").getAsString();
 
-                try (InputStream inputStream = new URL(downloadUrl).openStream();
-                     FileOutputStream outputStream = new FileOutputStream(new File(dataFolder, asset.getName()))) {
-                    inputStream.transferTo(outputStream);
+                try (InputStream inputStream = new URL(downloadUrl).openStream(); FileOutputStream outputStream = new FileOutputStream(new File(dataFolder, asset.getName()))) {
+                    byte[] buffer = new byte[4096];
+                    int bytesRead;
+                    while ((bytesRead = inputStream.read(buffer)) != -1) {
+                        outputStream.write(buffer, 0, bytesRead);
+                    }
                 }
 
-                KnockbackSync.INSTANCE.getLogger().info("Downloaded: " + asset.getName());
+                Base.INSTANCE.getLogger().info("Downloaded: " + asset.getName());
             }
         }
     }
@@ -87,29 +85,15 @@ public class BuildTypePie extends SimplePie {
         return lines.contains(hash);
     }
 
-    private static String getPluginJarHash() throws Exception {
-        URL jarUrl = Bukkit.getPluginManager().getPlugin("KnockbackSync").getClass().getProtectionDomain().getCodeSource().getLocation();
-        MessageDigest digest = MessageDigest.getInstance("SHA-256");
-        try (InputStream is = jarUrl.openStream()) {
-            byte[] buffer = new byte[8192];
-            int read;
-            while ((read = is.read(buffer)) > 0) {
-                digest.update(buffer, 0, read);
-            }
-        }
-        byte[] hash = digest.digest();
-        StringBuilder hexString = new StringBuilder();
-        for (byte b : hash) {
-            String hex = Integer.toHexString(0xff & b);
-            if (hex.length() == 1) hexString.append('0');
-            hexString.append(hex);
-        }
-        return hexString.toString();
-    }
-
     private static String readStringFromURL(String urlString) throws IOException {
         try (InputStream inputStream = new URL(urlString).openStream()) {
-            return new String(inputStream.readAllBytes(), StandardCharsets.UTF_8);
+            ByteArrayOutputStream result = new ByteArrayOutputStream();
+            byte[] buffer = new byte[4096];
+            int bytesRead;
+            while ((bytesRead = inputStream.read(buffer)) != -1) {
+                result.write(buffer, 0, bytesRead);
+            }
+            return result.toString("UTF-8");
         }
     }
 }

common/src/main/java/me/caseload/knockbacksync/stats/custom/ClientBrandsPie.java

@@ -0,0 +1,31 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.stats.AdvancedPie;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class ClientBrandsPie extends AdvancedPie {
+
+    // Gets the client versions of players online
+    public ClientBrandsPie() {
+        super("client_brands", () -> {
+            Map<String, Integer> valueMap = new HashMap<>();
+            for (PlatformPlayer player : Base.INSTANCE.getPlatformServer().getOnlinePlayers()) {
+                User user = player.getUser();
+                if (user == null || user.getClientVersion() == null) {
+                    valueMap.put("vanilla", valueMap.getOrDefault("vanilla", 0) + 1);
+                } else {
+                    valueMap.put(player.getClientBrand(), valueMap.getOrDefault(player.getClientBrand(), 0) + 1);
+                }
+            }
+            return valueMap;
+        });
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/Metrics.java

@@ -0,0 +1,9 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import me.caseload.knockbacksync.stats.CustomChart;
+
+public interface Metrics {
+
+    void addCustomChart(CustomChart chart);
+    void shutdown();
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/MetricsBase.java

@@ -0,0 +1,276 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import me.caseload.knockbacksync.stats.CustomChart;
+import me.caseload.knockbacksync.stats.JsonObjectBuilder;
+import org.jetbrains.annotations.NotNull;
+
+import javax.net.ssl.HttpsURLConnection;
+import java.io.*;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.HashSet;
+import java.util.Objects;
+import java.util.Set;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.TimeUnit;
+import java.util.function.BiConsumer;
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+import java.util.zip.GZIPOutputStream;
+
+public class MetricsBase {
+
+    /**
+     * The version of the Metrics class.
+     */
+    public static final String METRICS_VERSION = "3.1.0";
+
+    private static final String REPORT_URL = "https://bStats.org/api/v2/data/%s";
+
+    private final ScheduledExecutorService scheduler;
+
+    private final String platform;
+
+    private final String serverUuid;
+
+    private final int serviceId;
+
+    private final Consumer<JsonObjectBuilder> appendPlatformDataConsumer;
+
+    private final Consumer<JsonObjectBuilder> appendServiceDataConsumer;
+
+    private final Consumer<Runnable> submitTaskConsumer;
+
+    private final Supplier<Boolean> checkServiceEnabledSupplier;
+
+    private final BiConsumer<String, Throwable> errorLogger;
+
+    private final Consumer<String> infoLogger;
+
+    private final boolean logErrors;
+
+    private final boolean logSentData;
+
+    private final boolean logResponseStatusText;
+
+    private final Set<CustomChart> customCharts = new HashSet<>();
+
+    private final boolean enabled;
+
+    /**
+     * Creates a new MetricsBase class instance.
+     *
+     * @param platform                    The platform of the service.
+     * @param serviceId                   The id of the service.
+     * @param serverUuid                  The server uuid.
+     * @param enabled                     Whether or not data sending is enabled.
+     * @param appendPlatformDataConsumer  A consumer that receives a {@code JsonObjectBuilder} and
+     *                                    appends all platform-specific data.
+     * @param appendServiceDataConsumer   A consumer that receives a {@code JsonObjectBuilder} and
+     *                                    appends all service-specific data.
+     * @param submitTaskConsumer          A consumer that takes a runnable with the submit task. This can be
+     *                                    used to delegate the data collection to a another thread to prevent errors caused by
+     *                                    concurrency. Can be {@code null}.
+     * @param checkServiceEnabledSupplier A supplier to check if the service is still enabled.
+     * @param errorLogger                 A consumer that accepts log message and an error.
+     * @param infoLogger                  A consumer that accepts info log messages.
+     * @param logErrors                   Whether or not errors should be logged.
+     * @param logSentData                 Whether or not the sent data should be logged.
+     * @param logResponseStatusText       Whether or not the response status text should be logged.
+     * @param skipRelocateCheck           Whether or not the relocate check should be skipped.
+     */
+    public MetricsBase(
+            String platform,
+            String serverUuid,
+            int serviceId,
+            boolean enabled,
+            Consumer<JsonObjectBuilder> appendPlatformDataConsumer,
+            Consumer<JsonObjectBuilder> appendServiceDataConsumer,
+            Consumer<Runnable> submitTaskConsumer,
+            Supplier<Boolean> checkServiceEnabledSupplier,
+            BiConsumer<String, Throwable> errorLogger,
+            Consumer<String> infoLogger,
+            boolean logErrors,
+            boolean logSentData,
+            boolean logResponseStatusText,
+            boolean skipRelocateCheck) {
+        this.scheduler = getScheduledThreadPoolExecutor();
+        this.platform = platform;
+        this.serverUuid = serverUuid;
+        this.serviceId = serviceId;
+        this.enabled = enabled;
+        this.appendPlatformDataConsumer = appendPlatformDataConsumer;
+        this.appendServiceDataConsumer = appendServiceDataConsumer;
+        this.submitTaskConsumer = submitTaskConsumer;
+        this.checkServiceEnabledSupplier = checkServiceEnabledSupplier;
+        this.errorLogger = errorLogger;
+        this.infoLogger = infoLogger;
+        this.logErrors = logErrors;
+        this.logSentData = logSentData;
+        this.logResponseStatusText = logResponseStatusText;
+        if (!skipRelocateCheck) {
+            checkRelocation();
+        }
+        if (enabled) {
+            // WARNING: Removing the option to opt-out will get your plugin banned from
+            // bStats
+            startSubmitting();
+        }
+    }
+
+    private static @NotNull ScheduledThreadPoolExecutor getScheduledThreadPoolExecutor() {
+        ScheduledThreadPoolExecutor scheduler =
+                new ScheduledThreadPoolExecutor(
+                        1,
+                        task -> {
+                            Thread thread = new Thread(task, "bStats-Metrics");
+                            thread.setDaemon(true);
+                            return thread;
+                        });
+        // We want delayed tasks (non-periodic) that will execute in the future to be
+        // cancelled when the scheduler is shutdown.
+        // Otherwise, we risk preventing the server from shutting down even when
+        // MetricsBase#shutdown() is called
+        scheduler.setExecuteExistingDelayedTasksAfterShutdownPolicy(false);
+        return scheduler;
+    }
+
+    /**
+     * Gzips the given string.
+     *
+     * @param str The string to gzip.
+     * @return The gzipped string.
+     */
+    private static byte[] compress(final String str) throws IOException {
+        if (str == null) {
+            return null;
+        }
+        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
+        try (GZIPOutputStream gzip = new GZIPOutputStream(outputStream)) {
+            gzip.write(str.getBytes(StandardCharsets.UTF_8));
+        }
+        return outputStream.toByteArray();
+    }
+
+    public void addCustomChart(CustomChart chart) {
+        this.customCharts.add(chart);
+    }
+
+    public void shutdown() {
+        scheduler.shutdown();
+    }
+
+    private void startSubmitting() {
+        final Runnable submitTask =
+                () -> {
+                    if (!enabled || !checkServiceEnabledSupplier.get()) {
+                        // Submitting data or service is disabled
+                        scheduler.shutdown();
+                        return;
+                    }
+                    if (submitTaskConsumer != null) {
+                        submitTaskConsumer.accept(this::submitData);
+                    } else {
+                        this.submitData();
+                    }
+                };
+        // Many servers tend to restart at a fixed time at xx:00 which causes an uneven
+        // distribution of requests on the
+        // bStats backend. To circumvent this problem, we introduce some randomness into
+        // the initial and second delay.
+        // WARNING: You must not modify and part of this Metrics class, including the
+        // submit delay or frequency!
+        // WARNING: Modifying this code will get your plugin banned on bStats. Just
+        // don't do it!
+        long initialDelay = (long) (1000 * 60 * (3 + Math.random() * 3));
+        long secondDelay = (long) (1000 * 60 * (Math.random() * 30));
+        scheduler.schedule(submitTask, initialDelay, TimeUnit.MILLISECONDS);
+        scheduler.scheduleAtFixedRate(
+                submitTask, initialDelay + secondDelay, 1000 * 60 * 30, TimeUnit.MILLISECONDS);
+    }
+
+    private void submitData() {
+        final JsonObjectBuilder baseJsonBuilder = new JsonObjectBuilder();
+        appendPlatformDataConsumer.accept(baseJsonBuilder);
+        final JsonObjectBuilder serviceJsonBuilder = new JsonObjectBuilder();
+        appendServiceDataConsumer.accept(serviceJsonBuilder);
+        JsonObjectBuilder.JsonObject[] chartData =
+                customCharts.stream()
+                        .map(customChart -> customChart.getRequestJsonObject(errorLogger, logErrors))
+                        .filter(Objects::nonNull)
+                        .toArray(JsonObjectBuilder.JsonObject[]::new);
+        serviceJsonBuilder.appendField("id", serviceId);
+        serviceJsonBuilder.appendField("customCharts", chartData);
+        baseJsonBuilder.appendField("service", serviceJsonBuilder.build());
+        baseJsonBuilder.appendField("serverUUID", serverUuid);
+        baseJsonBuilder.appendField("metricsVersion", METRICS_VERSION);
+        JsonObjectBuilder.JsonObject data = baseJsonBuilder.build();
+        scheduler.execute(
+                () -> {
+                    try {
+                        // Send the data
+                        sendData(data);
+                    } catch (Exception e) {
+                        // Something went wrong! :(
+                        if (logErrors) {
+                            errorLogger.accept("Could not submit bStats metrics data", e);
+                        }
+                    }
+                });
+    }
+
+    private void sendData(JsonObjectBuilder.JsonObject data) throws Exception {
+        if (logSentData) {
+            infoLogger.accept("Sent bStats metrics data: " + data.toString());
+        }
+        String url = String.format(REPORT_URL, platform);
+        HttpsURLConnection connection = (HttpsURLConnection) new URL(url).openConnection();
+        // Compress the data to save bandwidth
+        byte[] compressedData = compress(data.toString());
+        connection.setRequestMethod("POST");
+        connection.addRequestProperty("Accept", "application/json");
+        connection.addRequestProperty("Connection", "close");
+        connection.addRequestProperty("Content-Encoding", "gzip");
+        connection.addRequestProperty("Content-Length", String.valueOf(compressedData.length));
+        connection.setRequestProperty("Content-Type", "application/json");
+        connection.setRequestProperty("User-Agent", "Metrics-Service/1");
+        connection.setDoOutput(true);
+        try (DataOutputStream outputStream = new DataOutputStream(connection.getOutputStream())) {
+            outputStream.write(compressedData);
+        }
+        StringBuilder builder = new StringBuilder();
+        try (BufferedReader bufferedReader =
+                     new BufferedReader(new InputStreamReader(connection.getInputStream()))) {
+            String line;
+            while ((line = bufferedReader.readLine()) != null) {
+                builder.append(line);
+            }
+        }
+        if (logResponseStatusText) {
+            infoLogger.accept("Sent data to bStats and received response: " + builder);
+        }
+    }
+
+    /**
+     * Checks that the class was properly relocated.
+     */
+    private void checkRelocation() {
+        // You can use the property to disable the check in your test environment
+        if (System.getProperty("bstats.relocatecheck") == null
+                || !System.getProperty("bstats.relocatecheck").equals("false")) {
+            // Maven's Relocate is clever and changes strings, too. So we have to use this
+            // little "trick" ... :D
+            final String defaultPackage =
+                    new String(new byte[]{'o', 'r', 'g', '.', 'b', 's', 't', 'a', 't', 's'});
+            final String examplePackage =
+                    new String(new byte[]{'y', 'o', 'u', 'r', '.', 'p', 'a', 'c', 'k', 'a', 'g', 'e'});
+            // We want to make sure no one just copy & pastes the example and uses the wrong
+            // package names
+            if (MetricsBase.class.getPackage().getName().startsWith(defaultPackage)
+                    || MetricsBase.class.getPackage().getName().startsWith(examplePackage)) {
+                throw new IllegalStateException("bStats Metrics class has not been relocated correctly!");
+            }
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/PlayerVersionsPie.java

@@ -0,0 +1,31 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import com.github.retrooper.packetevents.protocol.player.ClientVersion;
+import com.github.retrooper.packetevents.protocol.player.User;
+import me.caseload.knockbacksync.Base;
+import me.caseload.knockbacksync.manager.PlayerDataManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+import me.caseload.knockbacksync.stats.AdvancedPie;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class PlayerVersionsPie extends AdvancedPie {
+
+    // Gets the client versions of players online
+    public PlayerVersionsPie() {
+        super("player_version", () -> {
+            Map<String, Integer> valueMap = new HashMap<>();
+            for (PlatformPlayer player : Base.INSTANCE.getPlatformServer().getOnlinePlayers()) {
+                User user = player.getUser();
+                if (user == null || user.getClientVersion() == null) {
+                    valueMap.put(ClientVersion.UNKNOWN.toString(), valueMap.getOrDefault(ClientVersion.UNKNOWN.toString(), 0) + 1);
+                } else {
+                    valueMap.put(user.getClientVersion().toString(), valueMap.getOrDefault(user.getClientVersion().toString(), 0) + 1);
+                }
+            }
+            return valueMap;
+        });
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/PluginJarHashProvider.java

@@ -0,0 +1,33 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import java.io.InputStream;
+import java.net.URL;
+import java.security.MessageDigest;
+
+public class PluginJarHashProvider {
+
+    protected final URL jarURL;
+
+    public PluginJarHashProvider(URL jarURL) {
+        this.jarURL = jarURL;
+    }
+
+    public String getPluginJarHash() throws Exception {
+        MessageDigest digest = MessageDigest.getInstance("SHA-256");
+        try (InputStream is = jarURL.openStream()) {
+            byte[] buffer = new byte[8192];
+            int read;
+            while ((read = is.read(buffer)) > 0) {
+                digest.update(buffer, 0, read);
+            }
+        }
+        byte[] hash = digest.digest();
+        StringBuilder hexString = new StringBuilder();
+        for (byte b : hash) {
+            String hex = Integer.toHexString(0xff & b);
+            if (hex.length() == 1) hexString.append('0');
+            hexString.append(hex);
+        }
+        return hexString.toString();
+    }
+}

common/src/main/java/me/caseload/knockbacksync/stats/custom/StatsManager.java

@@ -0,0 +1,23 @@
+package me.caseload.knockbacksync.stats.custom;
+
+import lombok.Getter;
+import me.caseload.knockbacksync.Base;
+
+@Getter
+public abstract class StatsManager {
+
+    Metrics metrics;
+
+    public StatsManager(Metrics metrics) {
+        this.metrics = metrics;
+    }
+
+    public void init() {
+        Base.INSTANCE.getScheduler().runTaskAsynchronously(() -> {
+            BuildTypePie.determineBuildType(); // Function to calculate hash
+            metrics.addCustomChart(new PlayerVersionsPie());
+            metrics.addCustomChart(new BuildTypePie());
+            metrics.addCustomChart(new ClientBrandsPie());
+        });
+    }
+}

common/src/main/java/me/caseload/knockbacksync/util/ChatUtil.java

@@ -0,0 +1,21 @@
+package me.caseload.knockbacksync.util;
+
+import com.google.common.base.Preconditions;
+import org.jetbrains.annotations.NotNull;
+
+public class ChatUtil {
+
+    public static @NotNull String translateAlternateColorCodes(char altColorChar, @NotNull String textToTranslate) {
+        Preconditions.checkArgument(textToTranslate != null, "Cannot translate null text");
+        char[] b = textToTranslate.toCharArray();
+
+        for (int i = 0; i < b.length - 1; ++i) {
+            if (b[i] == altColorChar && "0123456789AaBbCcDdEeFfKkLlMmNnOoRrXx".indexOf(b[i + 1]) > -1) {
+                b[i] = 167;
+                b[i + 1] = Character.toLowerCase(b[i + 1]);
+            }
+        }
+
+        return new String(b);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/util/GeyserUtil.java

@@ -0,0 +1,64 @@
+package me.caseload.knockbacksync.util;
+
+import com.github.retrooper.packetevents.PacketEvents;
+import com.github.retrooper.packetevents.util.reflection.Reflection;
+import me.caseload.knockbacksync.Base;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.util.UUID;
+
+public class GeyserUtil {
+    private static boolean CHECKED_FOR_GEYSER = false;
+    private static boolean GEYSER_PRESENT = false;
+    private static Class<?> GEYSER_CLASS;
+    private static Class<?> GEYSER_API_CLASS;
+    private static Method GEYSER_API_METHOD;
+    private static Method CONNECTION_BY_UUID_METHOD;
+
+    public static boolean isGeyserPlayer(UUID uuid) {
+        if (!CHECKED_FOR_GEYSER) {
+            try {
+                ClassLoader classLoader = PacketEvents.getAPI().getPlugin().getClass().getClassLoader();
+                GEYSER_CLASS = classLoader.loadClass("org.geysermc.api.Geyser");
+                GEYSER_PRESENT = true;
+            } catch (ClassNotFoundException e) {
+                GEYSER_PRESENT = false;
+            }
+            CHECKED_FOR_GEYSER = true;
+        }
+
+        if (GEYSER_PRESENT) {
+            if (GEYSER_API_CLASS == null) {
+                try {
+                    ClassLoader classLoader = PacketEvents.getAPI().getPlugin().getClass().getClassLoader();
+                    GEYSER_API_CLASS = classLoader.loadClass("org.geysermc.api.GeyserApiBase");
+                } catch (ClassNotFoundException e) {
+                    e.printStackTrace();
+                }
+            }
+            if (GEYSER_API_METHOD == null) {
+                GEYSER_API_METHOD = Reflection.getMethodExact(GEYSER_CLASS, "api", null);
+            }
+            if (CONNECTION_BY_UUID_METHOD == null) {
+                CONNECTION_BY_UUID_METHOD = Reflection.getMethod(GEYSER_API_CLASS, "connectionByUuid", 0);
+            }
+            Object apiInstance = null;
+            try {
+                apiInstance = GEYSER_API_METHOD.invoke(null);
+            } catch (IllegalAccessException | InvocationTargetException e) {
+                e.printStackTrace();
+            }
+            Object connection = null;
+            try {
+                if (apiInstance != null) {
+                    connection = CONNECTION_BY_UUID_METHOD.invoke(apiInstance, uuid);
+                }
+            } catch (IllegalAccessException | InvocationTargetException e) {
+                e.printStackTrace();
+            }
+            return connection != null;
+        }
+        return false;
+    }
+}

common/src/main/java/me/caseload/knockbacksync/util/LegacyKnockback.java

@@ -0,0 +1,101 @@
+/*
+ * Legacy (Minecraft 1.8) melee knockback formula.
+ *
+ * This file is a port of the knockback calculation from BukkitOldCombatMechanics
+ * (kernitus/BukkitOldCombatMechanics), module ModulePlayerKnockback, which is
+ * licensed under the Mozilla Public License, v. 2.0:
+ *
+ *   This Source Code Form is subject to the terms of the Mozilla Public
+ *   License, v. 2.0. If a copy of the MPL was not distributed with this
+ *   file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * The MPL-2.0 does not carry the "Incompatible With Secondary Licenses" notice
+ * (Exhibit B), so per MPL-2.0 §3.3 this Covered Software may be distributed as
+ * part of a Larger Work under the GNU General Public License v3.0-or-later that
+ * governs the rest of KnockbackSync. The terms of the MPL continue to apply to
+ * this file. See the NOTICE file at the project root for attribution details.
+ */
+package me.caseload.knockbacksync.util;
+
+import com.github.retrooper.packetevents.util.Vector3d;
+import me.caseload.knockbacksync.manager.ConfigManager;
+import me.caseload.knockbacksync.player.PlatformPlayer;
+import me.caseload.knockbacksync.player.PlayerData;
+
+/**
+ * Computes the exact 1.8-style melee knockback vector applied to a victim, so that
+ * KnockbackSync can own the final melee velocity (horizontal + vertical) and then
+ * latency-correct it, rather than letting vanilla knockback win.
+ *
+ * <p>The math is a faithful reproduction of OldCombatMechanics' legacy player
+ * knockback so that values are identical to running OCM's old-player-knockback
+ * module, while KnockbackSync remains the single writer of the velocity.</p>
+ */
+public final class LegacyKnockback {
+
+    private LegacyKnockback() {
+    }
+
+    /**
+     * @param victim       the player receiving knockback
+     * @param attacker     the attacking player
+     * @param victimData   the victim's tracked data (for knockback resistance attribute)
+     * @param config       the plugin configuration (legacy knockback tunables)
+     * @return the 1.8-style velocity to apply to the victim, before latency Y-correction
+     */
+    public static Vector3d compute(PlatformPlayer victim, PlatformPlayer attacker,
+                                   PlayerData victimData, ConfigManager config) {
+        final double knockbackHorizontal = config.getLegacyKnockbackHorizontal();
+        final double knockbackVertical = config.getLegacyKnockbackVertical();
+        final double knockbackVerticalLimit = config.getLegacyKnockbackVerticalLimit();
+        final double knockbackExtraHorizontal = config.getLegacyKnockbackExtraHorizontal();
+        final double knockbackExtraVertical = config.getLegacyKnockbackExtraVertical();
+        final boolean netheriteKnockbackResistance = config.isLegacyKnockbackResistanceEnabled();
+
+        // Figure out base knockback direction (attacker -> victim) with vanilla jitter
+        // when the two are stacked on the exact same column.
+        double d0 = attacker.getX() - victim.getX();
+        double d1;
+        for (d1 = attacker.getZ() - victim.getZ(); d0 * d0 + d1 * d1 < 1.0E-4D;
+             d1 = (Math.random() - Math.random()) * 0.01D) {
+            d0 = (Math.random() - Math.random()) * 0.01D;
+        }
+
+        final double magnitude = Math.sqrt(d0 * d0 + d1 * d1);
+
+        // Player velocity before any friction is applied (pre-knockback motion).
+        final Vector3d v = victim.getVelocity();
+
+        // Apply friction (halve), then add base knockback.
+        double vx = (v.getX() / 2) - (d0 / magnitude * knockbackHorizontal);
+        double vy = (v.getY() / 2) + knockbackVertical;
+        double vz = (v.getZ() / 2) - (d1 / magnitude * knockbackHorizontal);
+
+        // Bonus knockback for sprinting and the Knockback enchantment.
+        int bonusKnockback = attacker.getWeaponKnockbackLevel();
+        if (attacker.isSprinting()) {
+            bonusKnockback++;
+        }
+
+        // NOTE: vanilla caps vertical BEFORE adding the sprint/enchant bonus vertical.
+        if (vy > knockbackVerticalLimit) {
+            vy = knockbackVerticalLimit;
+        }
+
+        if (bonusKnockback > 0) {
+            final float yaw = attacker.getYaw();
+            vx += -Math.sin(yaw * 3.1415927F / 180.0F) * (float) bonusKnockback * knockbackExtraHorizontal;
+            vy += knockbackExtraVertical;
+            vz += Math.cos(yaw * 3.1415927F / 180.0F) * (float) bonusKnockback * knockbackExtraHorizontal;
+        }
+
+        if (netheriteKnockbackResistance) {
+            // Each piece of netherite armour yields 10% horizontal resistance.
+            final double resistance = 1 - victimData.getKnockbackResistanceAttribute();
+            vx *= resistance;
+            vz *= resistance;
+        }
+
+        return new Vector3d(vx, vy, vz);
+    }
+}

common/src/main/java/me/caseload/knockbacksync/util/MathUtil.java

@@ -1,60 +1,75 @@
-package me.caseload.knockbacksync.util;
-
-public class MathUtil {
-
-    private static final double TERMINAL_VELOCITY = 3.92;
-    private static final double MULTIPLIER = 0.98;
-    private static final int MAX_TICKS = 20;
-
-    public static double calculateDistanceTraveled(double velocity, int time, double acceleration)
-    {
-        double totalDistance = 0;
-
-        for (int i = 0; i < time; i++)
-        {
-            totalDistance += velocity;
-            velocity = ((velocity - acceleration) * MULTIPLIER);
-            velocity = Math.min(velocity, TERMINAL_VELOCITY);
-        }
-
-        return totalDistance;
-    }
-
-    public static int calculateFallTime(double initialVelocity, double distance, double acceleration) {
-        double velocity = Math.abs(initialVelocity);
-        int ticks = 0;
-
-        while (distance > 0) {
-            if (ticks > MAX_TICKS)
-                return -1;
-
-            velocity += acceleration;
-            velocity = Math.min(velocity, TERMINAL_VELOCITY);
-            velocity *= MULTIPLIER;
-            distance -= velocity;
-            ticks++;
-        }
-
-        return ticks;
-    }
-
-    public static int calculateTimeToMaxVelocity(double targetVerticalVelocity, double acceleration) {
-        double a = -acceleration * MULTIPLIER;
-        double b = acceleration + TERMINAL_VELOCITY * MULTIPLIER;
-        double c = -2 * targetVerticalVelocity;
-
-        double discriminant = b * b - 4 * a * c;
-        if (discriminant < 0)
-            return 0;
-
-        double positiveRoot = (-b + Math.sqrt(discriminant)) / (2 * a);
-        return (int) Math.ceil(positiveRoot * 20);
-    }
-
-    public static double clamp(double num, double min, double max) {
-        if (num < min)
-            return min;
-
-        return Math.min(num, max);
-    }
+package me.caseload.knockbacksync.util;
+
+import me.caseload.knockbacksync.player.PlayerData;
+
+import me.caseload.knockbacksync.Base;
+
+public class MathUtil {
+
+    private static final double TERMINAL_VELOCITY = 3.92;
+    private static final double MULTIPLIER = 0.98;
+    private static final int MAX_TICKS = 30;
+
+    public static double getCompensatedVerticalVelocity(double velocity, double acceleration, int ticks) {
+        while (ticks > 0) {
+            velocity -= acceleration;
+            velocity *= MULTIPLIER;
+            ticks--;
+        }
+
+        return velocity;
+    }
+
+    public static double calculateDistanceTraveled(double velocity, int time, double acceleration) {
+        double totalDistance = 0;
+
+        for (int i = 0; i < time; i++) {
+            totalDistance += velocity;
+            velocity = ((velocity - acceleration) * MULTIPLIER);
+            velocity = Math.min(velocity, TERMINAL_VELOCITY);
+        }
+
+        return totalDistance;
+    }
+
+    public static int calculateFallTime(double initialVelocity, double distance, double acceleration) {
+        double velocity = Math.abs(initialVelocity);
+        int ticks = 0;
+
+        while (distance > 0) {
+            if (ticks > MAX_TICKS)
+                return -1;
+
+            velocity += acceleration;
+            velocity = Math.min(velocity, TERMINAL_VELOCITY);
+            velocity *= MULTIPLIER;
+            distance -= velocity;
+            ticks++;
+        }
+
+        return ticks;
+    }
+
+    public static int calculateTimeToMaxVelocity(double velocity, double acceleration) {
+        int ticks = 0;
+
+        while (velocity > 0) {
+            if (ticks > MAX_TICKS)
+                return -1;
+
+            velocity -= acceleration;
+            velocity = Math.min(velocity, TERMINAL_VELOCITY);
+            velocity *= MULTIPLIER;
+            ticks++;
+        }
+
+        return ticks;
+    }
+
+    public static double clamp(double num, double min, double max) {
+        if (num < min)
+            return min;
+
+        return Math.min(num, max);
+    }
 }

common/src/main/java/me/caseload/knockbacksync/util/NumberConversions.java

@@ -0,0 +1,31 @@
+package me.caseload.knockbacksync.util;
+
+import org.jetbrains.annotations.Nullable;
+
+public class NumberConversions {
+    public static long toLong(@Nullable Object object, long defaultValue) {
+        if (object instanceof Number) {
+            return ((Number) object).longValue();
+        } else {
+            try {
+                return Long.parseLong(object.toString());
+            } catch (NumberFormatException | NullPointerException ignored) {
+            }
+
+            return defaultValue;
+        }
+    }
+
+    public static int toInt(@Nullable Object object, int def) {
+        if (object instanceof Number) {
+            return ((Number) object).intValue();
+        } else {
+            try {
+                return Integer.parseInt(object.toString());
+            } catch (NumberFormatException | NullPointerException ignored) {
+            }
+
+            return def;
+        }
+    }
+}

common/src/main/java/me/caseload/knockbacksync/util/data/MethodFinder.java

@@ -0,0 +1,4 @@
+package me.caseload.knockbacksync.util.data;
+
+public interface MethodFinder {
+}

common/src/main/java/me/caseload/knockbacksync/util/data/Pair.java

@@ -0,0 +1,29 @@
+package me.caseload.knockbacksync.util.data;
+
+import lombok.Getter;
+
+import java.util.Objects;
+
+@Getter
+public class Pair<A, B> {
+    private final A first;
+    private final B second;
+
+    public Pair(A first, B second) {
+        this.first = first;
+        this.second = second;
+    }
+
+    public static <T, K> Pair<T, K> of(T a, K b) {
+        return new Pair<T, K>(a, b);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (!(o instanceof Pair)) {
+            return false;
+        }
+        Pair b = (Pair) o;
+        return Objects.equals(this.first, b.first) && Objects.equals(this.second, b.second);
+    }
+}