Merge pull request #365 from Exanthiax/develop

fix empty nbt

.github/CODEOWNERS

@@ -0,0 +1 @@
+* @WillFP

.github/workflows/java-ci.yml

@@ -1,6 +1,6 @@
 name: Java CI
 
-on: [ push, pull_request ]
+on: [ push, pull_request, workflow_dispatch ]
 
 jobs:
   build:
@@ -14,11 +14,11 @@ jobs:
         id: vars
         run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

.github/workflows/master-pr.yml

@@ -0,0 +1,21 @@
+name: PR Alert for Master Branch
+on:
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  alert:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Comment PR
+        uses: actions/github-script@v5
+        with:
+          github-token: ${{secrets.GITHUB_TOKEN}}
+          script: |
+            github.issues.createComment({
+              issue_number: context.issue.number,
+              owner: context.repo.owner,
+              repo: context.repo.repo,
+              body: '⚠️ PRs should not be opened against the `master` branch directly. Please use the `develop` branch as the base for your PRs. ⚠️'
+            })

.github/workflows/publish-release.yml

@@ -12,11 +12,11 @@ jobs:
       - name: Checkout latest code
         uses: actions/checkout@v2
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

.github/workflows/test-publish.yml

@@ -14,11 +14,11 @@ jobs:
         id: vars
         run: echo "::set-output name=sha_short::$(git rev-parse --short HEAD)"
 
-      - name: Set up JDK 17
+      - name: Set up JDK 21
         uses: actions/setup-java@v2
         with:
           distribution: 'temurin'
-          java-version: 17
+          java-version: 21
 
       - name: Setup build cache
         uses: actions/cache@v2.1.6

LICENSE.md

@@ -1,674 +1,23 @@
-                    GNU GENERAL PUBLIC LICENSE
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-not convey it at all.  For example, if you agree to terms that obligate you
-to collect a royalty for further conveying from those to whom you convey
-the Program, the only way you could satisfy both those terms and this
-License would be to refrain entirely from conveying the Program.
-
-  13. Use with the GNU Affero General Public License.
-
-  Notwithstanding any other provision of this License, you have
-permission to link or combine any covered work with a work licensed
-under version 3 of the GNU Affero General Public License into a single
-combined work, and to convey the resulting work.  The terms of this
-License will continue to apply to the part which is the covered work,
-but the special requirements of the GNU Affero General Public License,
-section 13, concerning interaction through a network will apply to the
-combination as such.
-
-  14. Revised Versions of this License.
-
-  The Free Software Foundation may publish revised and/or new versions of
-the GNU General Public License from time to time.  Such new versions will
-be similar in spirit to the present version, but may differ in detail to
-address new problems or concerns.
-
-  Each version is given a distinguishing version number.  If the
-Program specifies that a certain numbered version of the GNU General
-Public License "or any later version" applies to it, you have the
-option of following the terms and conditions either of that numbered
-version or of any later version published by the Free Software
-Foundation.  If the Program does not specify a version number of the
-GNU General Public License, you may choose any version ever published
-by the Free Software Foundation.
-
-  If the Program specifies that a proxy can decide which future
-versions of the GNU General Public License can be used, that proxy's
-public statement of acceptance of a version permanently authorizes you
-to choose that version for the Program.
-
-  Later license versions may give you additional or different
-permissions.  However, no additional obligations are imposed on any
-author or copyright holder as a result of your choosing to follow a
-later version.
-
-  15. Disclaimer of Warranty.
-
-  THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
-APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
-HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
-OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
-THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
-PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
-IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
-ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
-
-  16. Limitation of Liability.
-
-  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
-WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
-THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
-GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
-USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
-DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
-PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
-EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
-SUCH DAMAGES.
-
-  17. Interpretation of Sections 15 and 16.
-
-  If the disclaimer of warranty and limitation of liability provided
-above cannot be given local legal effect according to their terms,
-reviewing courts shall apply local law that most closely approximates
-an absolute waiver of all civil liability in connection with the
-Program, unless a warranty or assumption of liability accompanies a
-copy of the Program in return for a fee.
-
-                     END OF TERMS AND CONDITIONS
-
-            How to Apply These Terms to Your New Programs
-
-  If you develop a new program, and you want it to be of the greatest
-possible use to the public, the best way to achieve this is to make it
-free software which everyone can redistribute and change under these terms.
-
-  To do so, attach the following notices to the program.  It is safest
-to attach them to the start of each source file to most effectively
-state the exclusion of warranty; and each file should have at least
-the "copyright" line and a pointer to where the full notice is found.
-
-    <one line to give the program's name and a brief idea of what it does.>
-    Copyright (C) <year>  <name of author>
-
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <https://www.gnu.org/licenses/>.
-
-Also add information on how to contact you by electronic and paper mail.
-
-  If the program does terminal interaction, make it output a short
-notice like this when it starts in an interactive mode:
-
-    <program>  Copyright (C) <year>  <name of author>
-    This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
-    This is free software, and you are welcome to redistribute it
-    under certain conditions; type `show c' for details.
-
-The hypothetical commands `show w' and `show c' should show the appropriate
-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
-into proprietary programs.  If your program is a subroutine library, you
-may consider it more useful to permit linking proprietary applications with
-the library.  If this is what you want to do, use the GNU Lesser General
-Public License instead of this License.  But first, please read
-<https://www.gnu.org/licenses/why-not-lgpl.html>.
+The MIT License (MIT)
+=====================
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation
+files (the “Software”), to deal in the Software without
+restriction, including without limitation the rights to use,
+copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+OTHER DEALINGS IN THE SOFTWARE.

README.md

@@ -127,7 +127,7 @@ cd eco
 
 ## License
 
-eco is licensed under GNU GPL3. *Click here to read [the entire license](https://github.com/Auxilor/eco/blob/master/LICENSE.md).*
+eco is licensed under the MIT license. *Click here to read [the entire license](https://github.com/Auxilor/eco/blob/master/LICENSE.md).*
 
 <h1 align="center">
   Check out our partners!

build.gradle.kts

@@ -4,16 +4,17 @@ buildscript {
     }
 
     dependencies {
-        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.7.10")
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:1.9.21")
     }
 }
 
 plugins {
     id("java-library")
-    id("com.github.johnrengelman.shadow") version "7.1.2"
+    id("io.github.goooler.shadow") version "8.1.7"
     id("maven-publish")
     id("java")
-    kotlin("jvm") version "1.7.10"
+    kotlin("jvm") version "1.9.21"
+    kotlin("plugin.serialization") version "1.9.21"
 }
 
 dependencies {
@@ -21,28 +22,33 @@ dependencies {
     implementation(project(path = ":eco-core:core-plugin", configuration = "shadow"))
     implementation(project(":eco-core:core-proxy"))
     implementation(project(":eco-core:core-backend"))
+    implementation(project(":eco-core:core-backend-modern"))
     implementation(project(path = ":eco-core:core-nms:v1_17_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_18_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_18_R2", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R1", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R2", configuration = "reobf"))
     implementation(project(path = ":eco-core:core-nms:v1_19_R3", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R1", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R2", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_20_R3", configuration = "reobf"))
+    implementation(project(path = ":eco-core:core-nms:v1_21", configuration = "reobf"))
 }
 
 allprojects {
     apply(plugin = "java")
     apply(plugin = "java-library")
     apply(plugin = "maven-publish")
-    apply(plugin = "com.github.johnrengelman.shadow")
+    apply(plugin = "io.github.goooler.shadow")
     apply(plugin = "kotlin")
+    apply(plugin = "org.jetbrains.kotlin.plugin.serialization")
 
     repositories {
         mavenCentral()
-        mavenLocal()
-        maven("https://jitpack.io")
-
-        // CustomCrafting
-        maven("https://maven.wolfyscript.com/repository/public/")
+        maven("https://repo.auxilor.io/repository/maven-public/")
+        maven("https://jitpack.io") {
+            content { includeGroupByRegex("com\\.github\\..*") }
+        }
 
         // SuperiorSkyblock2
         maven("https://repo.bg-software.com/repository/api/")
@@ -80,28 +86,34 @@ allprojects {
         // LibsDisguises
         maven("https://repo.md-5.net/content/groups/public/")
 
-        // UltraEconomy
-        maven("https://repo.techscode.com/repository/maven-releases/")
-
         // PlayerPoints
         maven("https://repo.rosewooddev.io/repository/public/")
 
         // Denizen
         maven("https://maven.citizensnpcs.co/repo")
+
+        // IridiumSkyblock
+        maven("https://nexus.iridiumdevelopment.net/repository/maven-releases/")
+
+        // HuskPlugins
+        maven("https://repo.william278.net/releases")
+
+        // FancyHolograms
+        maven("https://repo.fancyplugins.de/releases")
     }
 
     dependencies {
         // Kotlin
-        implementation(kotlin("stdlib", version = "1.7.10"))
-        implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.6.2")
+        implementation(kotlin("stdlib", version = "1.9.21"))
+        implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.7.3")
 
         // Included in spigot jar, no need to move to implementation
         compileOnly("org.jetbrains:annotations:23.0.0")
         compileOnly("com.google.guava:guava:31.1-jre")
 
         // Test
-        testImplementation("org.junit.jupiter:junit-jupiter-api:5.8.2")
-        testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.8.2")
+        testImplementation("org.junit.jupiter:junit-jupiter-api:5.9.2")
+        testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.9.2")
 
         // Adventure
         implementation("net.kyori:adventure-api:4.10.1")
@@ -111,8 +123,8 @@ allprojects {
         implementation("net.kyori:adventure-text-serializer-legacy:4.10.1")
 
         // Other
-        implementation("com.github.ben-manes.caffeine:caffeine:3.1.0")
-        implementation("org.apache.maven:maven-artifact:3.8.5")
+        implementation("com.github.ben-manes.caffeine:caffeine:3.1.5")
+        implementation("org.apache.maven:maven-artifact:3.9.0")
     }
 
     tasks.withType<JavaCompile> {
@@ -136,58 +148,21 @@ allprojects {
     }
 
     tasks {
+        withType<Jar> {
+            duplicatesStrategy = DuplicatesStrategy.WARN
+        }
+
         compileKotlin {
             kotlinOptions {
                 jvmTarget = "17"
             }
         }
 
-        shadowJar {
-            relocate("org.bstats", "com.willfp.eco.libs.bstats")
-            relocate("redempt.crunch", "com.willfp.eco.libs.crunch")
-            relocate("org.apache.commons.lang3", "com.willfp.eco.libs.lang3")
-            relocate("org.apache.maven", "com.willfp.eco.libs.maven")
-            relocate("org.checkerframework", "com.willfp.eco.libs.checkerframework")
-            relocate("org.intellij", "com.willfp.eco.libs.intellij")
-            relocate("org.jetbrains.annotations", "com.willfp.eco.libs.jetbrains.annotations")
-            //relocate("org.jetbrains.exposed", "com.willfp.eco.libs.exposed")
-            relocate("org.objenesis", "com.willfp.eco.libs.objenesis")
-            relocate("org.reflections", "com.willfp.eco.libs.reflections")
-            relocate("javassist", "com.willfp.eco.libs.javassist")
-            relocate("javax.annotation", "com.willfp.eco.libs.annotation")
-            relocate("com.google.errorprone", "com.willfp.eco.libs.errorprone")
-            relocate("com.google.j2objc", "com.willfp.eco.libs.j2objc")
-            relocate("com.google.thirdparty", "com.willfp.eco.libs.google.thirdparty")
-            relocate("com.google.protobuf", "com.willfp.eco.libs.google.protobuf") // No I don't know either
-            relocate("google.protobuf", "com.willfp.eco.libs.protobuf") // Still don't know
-            relocate("com.zaxxer.hikari", "com.willfp.eco.libs.hikari")
-            //relocate("com.mysql", "com.willfp.eco.libs.mysql")
-            relocate("de.undercouch.bson4jackson", "com.willfp.eco.libs.bson4jackson")
-            relocate("com.fasterxml.jackson", "com.willfp.eco.libs.jackson")
-            relocate("com.mongodb", "com.willfp.eco.libs.mongodb")
-            relocate("org.bson", "com.willfp.eco.libs.bson")
-            relocate("org.litote", "com.willfp.eco.libs.litote")
-            relocate("org.reactivestreams", "com.willfp.eco.libs.reactivestreams")
-            relocate("reactor.", "com.willfp.eco.libs.reactor.") // Dot in name to be safe
-            relocate("com.moandjiezana.toml", "com.willfp.eco.libs.toml")
-
-            /*
-            Kotlin and caffeine are not shaded so that they can be accessed directly by eco plugins.
-            Also, not relocating adventure, because it's a pain in the ass, and it doesn't *seem* to be causing loader constraint violations.
-             */
-        }
-
         compileJava {
             dependsOn(clean)
             options.encoding = "UTF-8"
         }
 
-        java {
-            sourceCompatibility = JavaVersion.VERSION_17
-            targetCompatibility = JavaVersion.VERSION_17
-            withSourcesJar()
-        }
-
         test {
             useJUnitPlatform()
 
@@ -200,6 +175,53 @@ allprojects {
         build {
             dependsOn(shadowJar)
         }
+
+        withType<JavaCompile>().configureEach {
+            options.release = 17
+        }
+    }
+
+    java {
+        withSourcesJar()
+        toolchain {
+            languageVersion = JavaLanguageVersion.of(21)
+        }
+    }
+}
+
+tasks {
+    shadowJar {
+        relocate("org.bstats", "com.willfp.eco.libs.bstats")
+        relocate("redempt.crunch", "com.willfp.eco.libs.crunch")
+        relocate("org.apache.commons.lang3", "com.willfp.eco.libs.lang3")
+        relocate("org.apache.maven", "com.willfp.eco.libs.maven")
+        relocate("org.checkerframework", "com.willfp.eco.libs.checkerframework")
+        relocate("org.intellij", "com.willfp.eco.libs.intellij")
+        relocate("org.jetbrains.annotations", "com.willfp.eco.libs.jetbrains.annotations")
+        //relocate("org.jetbrains.exposed", "com.willfp.eco.libs.exposed")
+        relocate("org.objenesis", "com.willfp.eco.libs.objenesis")
+        relocate("org.reflections", "com.willfp.eco.libs.reflections")
+        relocate("javassist", "com.willfp.eco.libs.javassist")
+        relocate("javax.annotation", "com.willfp.eco.libs.annotation")
+        relocate("com.google.errorprone", "com.willfp.eco.libs.errorprone")
+        relocate("com.google.j2objc", "com.willfp.eco.libs.j2objc")
+        relocate("com.google.thirdparty", "com.willfp.eco.libs.google.thirdparty")
+        relocate("com.google.protobuf", "com.willfp.eco.libs.google.protobuf") // No I don't know either
+        relocate("google.protobuf", "com.willfp.eco.libs.protobuf") // Still don't know
+        relocate("com.zaxxer.hikari", "com.willfp.eco.libs.hikari")
+        //relocate("com.mysql", "com.willfp.eco.libs.mysql")
+        relocate("com.mongodb", "com.willfp.eco.libs.mongodb")
+        relocate("org.bson", "com.willfp.eco.libs.bson")
+        relocate("org.litote", "com.willfp.eco.libs.litote")
+        relocate("org.reactivestreams", "com.willfp.eco.libs.reactivestreams")
+        relocate("reactor.", "com.willfp.eco.libs.reactor.") // Dot in name to be safe
+        relocate("com.moandjiezana.toml", "com.willfp.eco.libs.toml")
+        relocate("com.willfp.modelenginebridge", "com.willfp.eco.libs.modelenginebridge")
+
+        /*
+        Kotlin and caffeine are not shaded so that they can be accessed directly by eco plugins.
+        Also, not relocating adventure, because it's a pain in the ass, and it doesn't *seem* to be causing loader constraint violations.
+         */
     }
 }
 

eco-api/build.gradle.kts

@@ -3,7 +3,8 @@ dependencies {
     compileOnly("net.kyori:adventure-platform-bukkit:4.1.0")
 
     // Other
-    compileOnly("org.spigotmc:spigot-api:1.17.1-R0.1-SNAPSHOT")
+    compileOnly("org.spigotmc:spigot-api:1.20.2-R0.1-SNAPSHOT")
+    compileOnly("commons-lang:commons-lang:2.6")
     compileOnly("com.comphenix.protocol:ProtocolLib:4.6.1-SNAPSHOT")
     compileOnly("com.google.code.gson:gson:2.8.8")
 }

eco-api/src/main/java/com/willfp/eco/core/Eco.java

@@ -30,11 +30,13 @@ import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import com.willfp.eco.core.proxy.ProxyFactory;
 import com.willfp.eco.core.scheduling.Scheduler;
 import net.kyori.adventure.platform.bukkit.BukkitAudiences;
+import net.kyori.adventure.text.Component;
 import org.apache.commons.lang.Validate;
 import org.bukkit.Location;
 import org.bukkit.NamespacedKey;
 import org.bukkit.configuration.ConfigurationSection;
 import org.bukkit.entity.Entity;
+import org.bukkit.entity.LivingEntity;
 import org.bukkit.entity.Mob;
 import org.bukkit.entity.Player;
 import org.bukkit.inventory.ItemStack;
@@ -135,6 +137,14 @@ public interface Eco {
     @NotNull
     Logger createLogger(@NotNull EcoPlugin plugin);
 
+    /**
+     * Get NOOP logger.
+     *
+     * @return The logger.
+     */
+    @NotNull
+    Logger getNOOPLogger();
+
     /**
      * Create a PAPI integration.
      *
@@ -170,7 +180,7 @@ public interface Eco {
      * @return The PluginCommandBase implementation
      */
     @NotNull
-    PluginCommandBase createPluginCommand(@NotNull CommandBase parentDelegate,
+    PluginCommandBase createPluginCommand(@NotNull PluginCommandBase parentDelegate,
                                           @NotNull EcoPlugin plugin,
                                           @NotNull String name,
                                           @NotNull String permission,
@@ -393,15 +403,6 @@ public interface Eco {
     @NotNull
     ServerProfile getServerProfile();
 
-    /**
-     * Unload a player profile from memory.
-     * <p>
-     * This will not save the profile first.
-     *
-     * @param uuid The uuid.
-     */
-    void unloadPlayerProfile(@NotNull UUID uuid);
-
     /**
      * Create dummy entity - never spawned, exists purely in code.
      *
@@ -528,9 +529,10 @@ public interface Eco {
      *
      * @param expression The expression.
      * @param context    The context.
-     * @return The value of the expression, or zero if invalid.
+     * @return The value of the expression, or null if invalid.
      */
-    double evaluate(@NotNull String expression,
+    @Nullable
+    Double evaluate(@NotNull String expression,
                     @NotNull PlaceholderContext context);
 
     /**
@@ -587,6 +589,19 @@ public interface Eco {
                                @NotNull String args,
                                @NotNull PlaceholderContext context);
 
+    /**
+     * Set a client-side entity display name.
+     *
+     * @param entity  The entity.
+     * @param player  The player.
+     * @param name    The display name.
+     * @param visible If the display name should be forcibly visible.
+     */
+    void setClientsideDisplayName(@NotNull LivingEntity entity,
+                                  @NotNull Player player,
+                                  @NotNull Component name,
+                                  boolean visible);
+
     /**
      * Get the instance of eco; the bridge between the api frontend and the implementation backend.
      *

eco-api/src/main/java/com/willfp/eco/core/EcoPlugin.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core;
 
+import com.google.common.collect.ImmutableList;
 import com.willfp.eco.core.command.impl.PluginCommand;
 import com.willfp.eco.core.config.base.ConfigYml;
 import com.willfp.eco.core.config.base.LangYml;
@@ -36,6 +37,8 @@ import org.jetbrains.annotations.Nullable;
 import java.io.File;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
 import java.util.Objects;
@@ -120,13 +123,21 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
     /**
      * The display module for the plugin.
+     *
+     * @deprecated Plugins can now have multiple display modules.
      */
+    @Deprecated(since = "6.72.0")
     private DisplayModule displayModule;
 
+    /**
+     * The display modules for the plugin.
+     */
+    private List<DisplayModule> displayModules = new ArrayList<>();
+
     /**
      * The logger for the plugin.
      */
-    private final Logger logger;
+    private Logger logger;
 
     /**
      * If the server is running an outdated version of the plugin.
@@ -164,6 +175,11 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      */
     private final ListMap<LifecyclePosition, Runnable> afterLoad = new ListMap<>();
 
+    /**
+     * The tasks to run on task creation.
+     */
+    private final ListMap<LifecyclePosition, Runnable> onCreateTasks = new ListMap<>();
+
     /**
      * Create a new plugin.
      * <p>
@@ -425,7 +441,18 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
         this.loadPluginCommands().forEach(PluginCommand::register);
 
-        this.getScheduler().runLater(this::afterLoad, 1);
+        // Run preliminary reload to resolve load order issues
+        this.getScheduler().runLater(() -> {
+            Logger before = this.getLogger();
+            // Temporary silence logger.
+            this.logger = Eco.get().getNOOPLogger();
+
+            this.reload(false);
+
+            this.logger = before;
+        }, 1);
+
+        this.getScheduler().runLater(this::afterLoad, 2);
 
         if (this.isSupportingExtensions()) {
             this.getExtensionLoader().loadExtensions();
@@ -539,10 +566,15 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Default code to be executed after the server is up.
      */
     public final void afterLoad() {
-        this.displayModule = createDisplayModule();
+        DisplayModule module = createDisplayModule();
+        if (module != null) {
+            Display.registerDisplayModule(module);
+            this.displayModules.add(module);
+        }
 
-        if (this.getDisplayModule() != null) {
-            Display.registerDisplayModule(this.getDisplayModule());
+        for (DisplayModule displayModule : this.loadDisplayModules()) {
+            Display.registerDisplayModule(displayModule);
+            this.displayModules.add(displayModule);
         }
 
         if (Prerequisite.HAS_PROTOCOLLIB.isMet()) {
@@ -559,8 +591,9 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
             this.getLogger().severe("");
             this.getLogger().severe("You don't seem to be running paper!");
             this.getLogger().severe("Paper is strongly recommended for all servers,");
-            this.getLogger().severe("and some things may not function properly without it");
-            this.getLogger().severe("Download Paper from &fhttps://papermc.io");
+            this.getLogger().severe("and many features may not function properly without it");
+            this.getLogger().severe("Download Paper from https://papermc.io");
+            this.getLogger().severe("It's a drop-in replacement for Spigot, so it's easy to switch.");
             this.getLogger().severe("");
             this.getLogger().severe("----------------------------");
             this.getLogger().severe("");
@@ -601,14 +634,30 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Reload the plugin.
      */
     public final void reload() {
+        this.reload(true);
+    }
+
+    /**
+     * Reload the plugin.
+     *
+     * @param cancelTasks If tasks should be cancelled.
+     */
+    public final void reload(final boolean cancelTasks) {
         this.getConfigHandler().updateConfigs();
 
-        this.getScheduler().cancelAll();
+        if (cancelTasks) {
+            this.getScheduler().cancelAll();
+        }
+
         this.getConfigHandler().callUpdate();
         this.getConfigHandler().callUpdate(); // Call twice to fix issues
 
         this.handleLifecycle(this.onReload, this::handleReload);
 
+        if (cancelTasks) {
+            this.handleLifecycle(this.onCreateTasks, this::createTasks);
+        }
+
         for (Extension extension : this.extensionLoader.getLoadedExtensions()) {
             extension.handleReload();
         }
@@ -634,6 +683,26 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
         this.onReload.append(position, task);
     }
 
+    /**
+     * Add new task to run on createTasks.
+     *
+     * @param task The task.
+     */
+    public final void onCreateTasks(@NotNull final Runnable task) {
+        this.onCreateTasks(LifecyclePosition.END, task);
+    }
+
+    /**
+     * Add new task to run on createTasks.
+     *
+     * @param position The position to run the task.
+     * @param task     The task.
+     */
+    public final void onCreateTasks(@NotNull final LifecyclePosition position,
+                                    @NotNull final Runnable task) {
+        this.onCreateTasks.append(position, task);
+    }
+
     /**
      * Reload the plugin and return the time taken to reload.
      *
@@ -722,6 +791,15 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
 
     }
 
+    /**
+     * The plugin-specific code to create tasks.
+     * <p>
+     * Override when needed.
+     */
+    protected void createTasks() {
+
+    }
+
     /**
      * The plugin-specific code to be executed after the server is up.
      * <p>
@@ -837,14 +915,25 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Create the display module for the plugin.
      *
      * @return The display module, or null.
+     * @deprecated Use {@link #loadDisplayModules()} instead.
      */
     @Nullable
+    @Deprecated(since = "6.72.0")
     protected DisplayModule createDisplayModule() {
         Validate.isTrue(this.getDisplayModule() == null, "Display module exists!");
 
         return null;
     }
 
+    /**
+     * Load display modules.
+     *
+     * @return The display modules.
+     */
+    protected List<DisplayModule> loadDisplayModules() {
+        return new ArrayList<>();
+    }
+
     /**
      * Get the minimum version of eco to use the plugin.
      *
@@ -1094,12 +1183,23 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
      * Get the plugin's display module.
      *
      * @return The display module.
+     * @deprecated Use {@link #getDisplayModules()} instead.
      */
     @Nullable
+    @Deprecated(since = "6.72.0", forRemoval = true)
     public DisplayModule getDisplayModule() {
         return this.displayModule;
     }
 
+    /**
+     * Get the plugin's display modules.
+     *
+     * @return The display modules.
+     */
+    public List<DisplayModule> getDisplayModules() {
+        return ImmutableList.copyOf(this.displayModules);
+    }
+
     /**
      * Get if the plugin is outdated.
      *
@@ -1150,6 +1250,16 @@ public abstract class EcoPlugin extends JavaPlugin implements PluginLike, Regist
         return this.getMetadataValueFactory().create(value);
     }
 
+    /**
+     * Get if all {@link com.willfp.eco.core.data.keys.PersistentDataKey}'s for this
+     * plugin should be saved locally (via data.yml.) even if eco is using a database.
+     *
+     * @return If using local storage.
+     */
+    public boolean isUsingLocalStorage() {
+        return this.configYml.isUsingLocalStorage();
+    }
+
     @Override
     @NotNull
     public final String getID() {

eco-api/src/main/java/com/willfp/eco/core/PluginProps.java

@@ -55,7 +55,7 @@ public final class PluginProps {
     private final Map<String, String> environment = new HashMap<>();
 
     /**
-     * If the plugin uses reflective reload (via {@link com.willfp.eco.core.config.updating.ConfigUpdater}).
+     * If the plugin uses reflective reload.
      */
     private boolean usesReflectiveReload = true;
 

eco-api/src/main/java/com/willfp/eco/core/Prerequisite.java

@@ -37,11 +37,44 @@ public class Prerequisite {
             "Requires server to have ProtocolLib"
     );
 
+    /**
+     * Requires the server to be running 1.21.
+     */
+    public static final Prerequisite HAS_1_21 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("1_21"),
+            "Requires server to be running 1.21+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.5.
+     */
+    public static final Prerequisite HAS_1_20_5 = new Prerequisite(
+            () -> (ProxyConstants.NMS_VERSION.contains("1_20_") && !ProxyConstants.NMS_VERSION.contains("R"))
+                    || HAS_1_21.isMet(),
+            "Requires server to be running 1.20.5+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.3.
+     */
+    public static final Prerequisite HAS_1_20_3 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("20_R3") || HAS_1_20_5.isMet(),
+            "Requires server to be running 1.20.3+"
+    );
+
+    /**
+     * Requires the server to be running 1.20.
+     */
+    public static final Prerequisite HAS_1_20 = new Prerequisite(
+            () -> ProxyConstants.NMS_VERSION.contains("20") || HAS_1_20_3.isMet(),
+            "Requires server to be running 1.20+"
+    );
+
     /**
      * Requires the server to be running 1.19.4.
      */
     public static final Prerequisite HAS_1_19_4 = new Prerequisite(
-            () -> ProxyConstants.NMS_VERSION.contains("19_R3"),
+            () -> ProxyConstants.NMS_VERSION.contains("19_R3") || HAS_1_20.isMet(),
             "Requires server to be running 1.19.4+"
     );
 
@@ -49,7 +82,7 @@ public class Prerequisite {
      * Requires the server to be running 1.19.
      */
     public static final Prerequisite HAS_1_19 = new Prerequisite(
-            () -> ProxyConstants.NMS_VERSION.contains("19"),
+            () -> ProxyConstants.NMS_VERSION.contains("19") || HAS_1_20.isMet(),
             "Requires server to be running 1.19+"
     );
 

eco-api/src/main/java/com/willfp/eco/core/config/base/ConfigYml.java

@@ -9,6 +9,11 @@ import org.jetbrains.annotations.NotNull;
  * Default plugin config.yml.
  */
 public class ConfigYml extends BaseConfig {
+    /**
+     * The use local storage key.
+     */
+    public static final String KEY_USES_LOCAL_STORAGE = "use-local-storage";
+
     /**
      * Config.yml.
      *
@@ -52,4 +57,13 @@ public class ConfigYml extends BaseConfig {
                      final boolean removeUnused) {
         super(name, plugin, removeUnused, ConfigType.YAML);
     }
+
+    /**
+     * Get if the plugin is using local storage.
+     *
+     * @return The prefix.
+     */
+    public boolean isUsingLocalStorage() {
+        return this.getBool(KEY_USES_LOCAL_STORAGE);
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/Config.java

@@ -15,6 +15,7 @@ import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -596,7 +597,10 @@ public interface Config extends Cloneable, PlaceholderInjectable {
      */
     default double getDoubleFromExpression(@NotNull String path,
                                            @NotNull PlaceholderContext context) {
-        return NumberUtils.evaluateExpression(this.getString(path), context.withInjectableContext(this));
+        return Objects.requireNonNullElseGet(
+                this.getDoubleOrNull(path),
+                () -> NumberUtils.evaluateExpression(this.getString(path), context.withInjectableContext(this))
+        );
     }
 
     /**
@@ -648,6 +652,32 @@ public interface Config extends Cloneable, PlaceholderInjectable {
     @Nullable
     List<? extends Config> getSubsectionsOrNull(@NotNull String path);
 
+    /**
+     * Get a big decimal from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or 0 if not found.
+     */
+    @NotNull
+    default BigDecimal getBigDecimal(@NotNull final String path) {
+        return Objects.requireNonNullElse(getBigDecimalOrNull(path), BigDecimal.ZERO);
+    }
+
+    /**
+     * Get a big decimal from config.
+     *
+     * @param path The key to fetch the value from.
+     * @return The found value, or null if not found.
+     */
+    @Nullable
+    default BigDecimal getBigDecimalOrNull(@NotNull final String path) {
+        if (this.has(path)) {
+            return new BigDecimal(this.getString(path));
+        } else {
+            return null;
+        }
+    }
+
     /**
      * Get config type.
      *

eco-api/src/main/java/com/willfp/eco/core/config/interfaces/LoadableConfig.java

@@ -29,6 +29,22 @@ public interface LoadableConfig extends Config {
      */
     void save() throws IOException;
 
+    /**
+     * Save the config asynchronously.
+     */
+    default void saveAsync() {
+        // This default implementation exists purely for backwards compatibility
+        // with legacy Config implementations that don't have saveAsync().
+        // Default eco implementations of Config have saveAsync() implemented.
+        new Thread(() -> {
+            try {
+                this.save();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }).start();
+    }
+
     /**
      * Get the config file.
      *

eco-api/src/main/java/com/willfp/eco/core/config/updating/ConfigUpdater.java

@@ -38,12 +38,16 @@ import java.lang.annotation.Target;
  * <p>
  * By having a plugin as a parameter, you shouldn't really need getInstance()
  * calls in your code.
- *
+ * <p>
  * While flexible, this can lead to long initialization times, so this feature
  * can be disabled in eco.yml with the uses-reflective-reload option.
+ *
+ * @deprecated This has been deprecated due to the poor control flow and long startup times.
  */
 @Retention(RetentionPolicy.RUNTIME)
 @Target(ElementType.METHOD)
 @Documented
+@Deprecated(since = "6.67.0", forRemoval = true)
+@SuppressWarnings("DeprecatedIsStillUsed")
 public @interface ConfigUpdater {
 }

eco-api/src/main/java/com/willfp/eco/core/data/ExtendedPersistentDataContainer.java

@@ -87,6 +87,10 @@ public interface ExtendedPersistentDataContainer {
      * @return The extended container.
      */
     static ExtendedPersistentDataContainer extend(@NotNull PersistentDataContainer base) {
+        if (base instanceof ExtendedPersistentDataContainer) {
+            return (ExtendedPersistentDataContainer) base;
+        }
+
         return Eco.get().adaptPdc(base);
     }
 

eco-api/src/main/java/com/willfp/eco/core/data/ServerProfile.java

@@ -9,6 +9,22 @@ import org.jetbrains.annotations.NotNull;
  * Profiles save automatically, so there is no need to save after changes.
  */
 public interface ServerProfile extends Profile {
+    /**
+     * Get the server ID.
+     *
+     * @return The server ID.
+     */
+    @NotNull
+    String getServerID();
+
+    /**
+     * Get the local server ID.
+     *
+     * @return The local server ID.
+     */
+    @NotNull
+    String getLocalServerID();
+
     /**
      * Load the server profile.
      *

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKey.java

@@ -29,6 +29,31 @@ public final class PersistentDataKey<T> {
      */
     private final PersistentDataKeyType<T> type;
 
+    /**
+     * If the key uses local storage.
+     */
+    private final boolean isLocal;
+
+    /**
+     * Create a new Persistent Data Key.
+     *
+     * @param key          The key.
+     * @param type         The data type.
+     * @param defaultValue The default value.
+     * @param isLocal        If the key uses local storage.
+     */
+    public PersistentDataKey(@NotNull final NamespacedKey key,
+                             @NotNull final PersistentDataKeyType<T> type,
+                             @NotNull final T defaultValue,
+                             final boolean isLocal) {
+        this.key = key;
+        this.defaultValue = defaultValue;
+        this.type = type;
+        this.isLocal = isLocal;
+
+        Eco.get().registerPersistentKey(this);
+    }
+
     /**
      * Create a new Persistent Data Key.
      *
@@ -42,6 +67,7 @@ public final class PersistentDataKey<T> {
         this.key = key;
         this.defaultValue = defaultValue;
         this.type = type;
+        this.isLocal = false;
 
         Eco.get().registerPersistentKey(this);
     }
@@ -82,6 +108,15 @@ public final class PersistentDataKey<T> {
         return this.type;
     }
 
+    /**
+     * Get if the key uses local storage.
+     *
+     * @return If the key uses local storage.
+     */
+    public boolean isLocal() {
+        return this.isLocal;
+    }
+
     /**
      * Get all persistent data keys.
      *

eco-api/src/main/java/com/willfp/eco/core/data/keys/PersistentDataKeyType.java

@@ -4,6 +4,7 @@ import com.willfp.eco.core.config.interfaces.Config;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import java.math.BigDecimal;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Objects;
@@ -49,6 +50,11 @@ public final class PersistentDataKeyType<T> {
      */
     public static final PersistentDataKeyType<Config> CONFIG = new PersistentDataKeyType<>("CONFIG");
 
+    /**
+     * Big Decimal.
+     */
+    public static final PersistentDataKeyType<BigDecimal> BIG_DECIMAL = new PersistentDataKeyType<>("BIG_DECIMAL");
+
     /**
      * The name of the key type.
      */

eco-api/src/main/java/com/willfp/eco/core/display/Display.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.display;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.fast.FastItemStack;
 import com.willfp.eco.core.integrations.guidetection.GUIDetectionManager;
 import com.willfp.eco.util.NamespacedKeyUtils;
@@ -68,8 +69,10 @@ public final class Display {
 
         Display.revert(itemStack);
 
-        if (!itemStack.hasItemMeta()) {
-            return itemStack;
+        if (!Eco.get().getEcoPlugin().getConfigYml().getBool("display-without-meta")) {
+            if (!itemStack.hasItemMeta()) {
+                return itemStack;
+            }
         }
 
         ItemStack original = itemStack.clone();
@@ -208,12 +211,22 @@ public final class Display {
                 new ArrayList<>()
         );
 
-        modules.removeIf(it -> it.getPluginName().equalsIgnoreCase(module.getPluginName()));
         modules.add(module);
 
         REGISTERED_MODULES.put(module.getWeight(), modules);
     }
 
+    /**
+     * Unregister a display module.
+     *
+     * @param module The module.
+     */
+    public static void unregisterDisplayModule(@NotNull final DisplayModule module) {
+        for (List<DisplayModule> modules : REGISTERED_MODULES.values()) {
+            modules.remove(module);
+        }
+    }
+
     private Display() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }

eco-api/src/main/java/com/willfp/eco/core/events/DropQueuePushEvent.java

@@ -27,7 +27,7 @@ public class DropQueuePushEvent extends PlayerEvent implements Cancellable {
     /**
      * The items.
      */
-    private final Collection<? extends ItemStack> items;
+    private Collection<? extends ItemStack> items;
 
     /**
      * The xp.
@@ -114,6 +114,15 @@ public class DropQueuePushEvent extends PlayerEvent implements Cancellable {
         return items;
     }
 
+    /**
+     * Set the items to be dropped.
+     *
+     * @param items The items.
+     */
+    public void setItems(Collection<? extends ItemStack> items) {
+        this.items = items;
+    }
+
     /**
      * Get the xp to be dropped.
      *

eco-api/src/main/java/com/willfp/eco/core/extensions/ExtensionMetadata.java

@@ -13,6 +13,8 @@ import java.io.File;
  * @param version The extension version.
  * @param name    The extension name.
  * @param author  The extension's author.
+ * @param file   The extension's file.
+ * @param minimumPluginVersion The minimum plugin version required for this extension.
  */
 public record ExtensionMetadata(@NotNull String version,
                                 @NotNull String name,

eco-api/src/main/java/com/willfp/eco/core/fast/FastItemStack.java

@@ -164,15 +164,23 @@ public interface FastItemStack extends PersistentDataHolder {
      * The returned PersistentDataContainer will not modify the item until the tag is set.
      *
      * @return The base NBT tag.
+     * @deprecated Items are now component-based.
      */
-    PersistentDataContainer getBaseTag();
+    @Deprecated(forRemoval = true, since = "6.70.0")
+    default PersistentDataContainer getBaseTag() {
+        throw new UnsupportedOperationException("Not supported in 1.20.5+");
+    }
 
     /**
      * Set the base NBT tag (Not PublicBukkitValues, the base) from a PersistentDataContainer.
      *
      * @param container The PersistentDataContainer.
+     * @deprecated Items are now component-based.
      */
-    void setBaseTag(@Nullable PersistentDataContainer container);
+    @Deprecated(forRemoval = true, since = "6.70.0")
+    default void setBaseTag(@Nullable PersistentDataContainer container) {
+        throw new UnsupportedOperationException("Not supported in 1.20.5+");
+    }
 
     /**
      * Get the type of the item.

eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuBuilder.java

@@ -142,6 +142,26 @@ public interface MenuBuilder extends PageBuilder {
         return this.onRender((player, menu) -> menu.setState(player, Page.MAX_PAGE_KEY, pages.apply(player)));
     }
 
+    /**
+     * Set the default page.
+     *
+     * @param page The page.
+     * @return The builder.
+     */
+    default MenuBuilder defaultPage(final int page) {
+        return this.maxPages(player -> page);
+    }
+
+    /**
+     * Set the default page dynamically for a player.
+     *
+     * @param page The default page.
+     * @return The builder.
+     */
+    default MenuBuilder defaultPage(@NotNull final Function<Player, Integer> page) {
+        return this.onOpen((player, menu) -> menu.setState(player, Page.PAGE_KEY, page.apply(player)));
+    }
+
     /**
      * Add a menu close handler.
      *

eco-api/src/main/java/com/willfp/eco/core/gui/menu/MenuEventHandler.java

@@ -5,6 +5,8 @@ import org.jetbrains.annotations.NotNull;
 
 /**
  * Handles menu events.
+ *
+ * @param <T> The type of event to handle.x
  */
 public abstract class MenuEventHandler<T extends MenuEvent> {
     /**

eco-api/src/main/java/com/willfp/eco/core/gui/slot/ConfigSlot.java

@@ -86,7 +86,7 @@ public class ConfigSlot extends CustomSlot {
             for (String command : config.getStrings(configKey)) {
                 if (command.startsWith("console:")) {
                     commands.add(new CommandToDispatch(
-                            StringUtils.removePrefix("console:", command),
+                            StringUtils.removePrefix(command, "console:"),
                             true
                     ));
                 } else {

eco-api/src/main/java/com/willfp/eco/core/gui/slot/CustomSlot.java

@@ -2,6 +2,7 @@ package com.willfp.eco.core.gui.slot;
 
 import com.willfp.eco.core.gui.menu.Menu;
 import org.bukkit.entity.Player;
+import org.bukkit.event.inventory.ClickType;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -76,6 +77,15 @@ public abstract class CustomSlot implements Slot {
         return delegate;
     }
 
+    @Override
+    public boolean shouldRenderOnClick(@NotNull final ClickType clickType) {
+        if (delegate == null) {
+            throw new IllegalStateException("Custom Slot was not initialized!");
+        }
+
+        return delegate.shouldRenderOnClick(clickType);
+    }
+
     @Override
     public final int getRows() {
         return Slot.super.getRows();

eco-api/src/main/java/com/willfp/eco/core/gui/slot/Slot.java

@@ -7,6 +7,7 @@ import com.willfp.eco.core.gui.slot.functional.SlotProvider;
 import com.willfp.eco.core.items.TestableItem;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
+import org.bukkit.event.inventory.ClickType;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -92,6 +93,27 @@ public interface Slot extends GUIComponent {
         return false;
     }
 
+    /**
+     * If the slot should re-render the menu if clicked.
+     *
+     * @return If the slot should re-render.
+     * @deprecated Use {@link Slot#shouldRenderOnClick(ClickType)} instead.
+     */
+    @Deprecated(since = "6.66.0", forRemoval = true)
+    default boolean shouldRenderOnClick() {
+        return shouldRenderOnClick(ClickType.LEFT);
+    }
+
+    /**
+     * If the slot should re-render the menu if clicked.
+     *
+     * @param clickType The click type.
+     * @return If the slot should re-render.
+     */
+    default boolean shouldRenderOnClick(@NotNull final ClickType clickType) {
+        return true;
+    }
+
     @Override
     default int getRows() {
         return 1;

eco-api/src/main/java/com/willfp/eco/core/gui/slot/SlotBuilder.java

@@ -196,6 +196,7 @@ public interface SlotBuilder {
      * @deprecated Use {@link SlotBuilder#setUpdater(SlotUpdater)} instead.
      */
     @Deprecated
+    @SuppressWarnings("DeprecatedIsStillUsed")
     default SlotBuilder setModifier(@NotNull SlotModifier modifier) {
         return setUpdater((player, menu, previous) -> {
             modifier.modify(player, menu, previous);

eco-api/src/main/java/com/willfp/eco/core/integrations/IntegrationRegistry.java

@@ -17,6 +17,13 @@ import java.util.function.Supplier;
  * @param <T> The type of integration.
  */
 public class IntegrationRegistry<T extends Integration> extends Registry<T> {
+    /**
+     * Create a new integration registry.
+     */
+    public IntegrationRegistry() {
+        super();
+    }
+
     @Override
     public @NotNull T register(@NotNull final T element) {
         return executeSafely(() -> super.register(element), element);
@@ -110,7 +117,7 @@ public class IntegrationRegistry<T extends Integration> extends Registry<T> {
                                 @Nullable final R defaultValue) {
         try {
             return action.get();
-        } catch (final Exception e) {
+        } catch (final Exception | LinkageError e) {
             Eco.get().getEcoPlugin().getLogger().warning("Integration for " + integration.getPluginName() + " threw an exception!");
             Eco.get().getEcoPlugin().getLogger().warning("The integration will be disabled.");
             e.printStackTrace();

eco-api/src/main/java/com/willfp/eco/core/integrations/placeholder/PlaceholderManager.java

@@ -98,6 +98,7 @@ public final class PlaceholderManager {
         // Storing as immutable set leads to slower times to register placeholders, but much
         // faster times to access registrations.
         Set<Placeholder> pluginPlaceholders = new HashSet<>(REGISTERED_PLACEHOLDERS.get(placeholder.getPlugin()));
+        pluginPlaceholders.removeIf(p -> p.getPattern().equals(placeholder.getPattern()));
         pluginPlaceholders.add(placeholder);
         REGISTERED_PLACEHOLDERS.put(placeholder.getPlugin(), ImmutableSet.copyOf(pluginPlaceholders));
     }
@@ -149,6 +150,7 @@ public final class PlaceholderManager {
      */
     @Deprecated(since = "6.56.0", forRemoval = true)
     @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player) {
         return translatePlaceholders(text, player, EMPTY_INJECTABLE);
@@ -165,10 +167,19 @@ public final class PlaceholderManager {
      */
     @Deprecated(since = "6.56.0", forRemoval = true)
     @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player,
                                                @NotNull final PlaceholderInjectable context) {
-        return translatePlaceholders(text, player, context, new ArrayList<>());
+        return translatePlaceholders(
+                text,
+                new PlaceholderContext(
+                        player,
+                        null,
+                        context,
+                        new ArrayList<>()
+                )
+        );
     }
 
     /**
@@ -183,6 +194,7 @@ public final class PlaceholderManager {
      */
     @Deprecated(since = "6.56.0", forRemoval = true)
     @NotNull
+    @SuppressWarnings("DeprecatedIsStillUsed")
     public static String translatePlaceholders(@NotNull final String text,
                                                @Nullable final Player player,
                                                @NotNull final PlaceholderInjectable context,

eco-api/src/main/java/com/willfp/eco/core/items/CustomItem.java

@@ -1,7 +1,6 @@
 package com.willfp.eco.core.items;
 
 import com.willfp.eco.core.Eco;
-import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -55,7 +54,7 @@ public class CustomItem implements TestableItem {
          */
         Eco.get().getEcoPlugin().getScheduler().runLater(() -> {
             if (!matches(getItem())) {
-                Bukkit.getLogger().severe("Item with key " + key + " is invalid!");
+                Eco.get().getEcoPlugin().getLogger().severe("Item with key " + key + " is invalid!");
             }
         }, 1);
     }

eco-api/src/main/java/com/willfp/eco/core/items/Items.java

@@ -13,6 +13,7 @@ import com.willfp.eco.core.recipe.parts.TestableStack;
 import com.willfp.eco.core.recipe.parts.UnrestrictedMaterialTestableItem;
 import com.willfp.eco.util.NamespacedKeyUtils;
 import com.willfp.eco.util.NumberUtils;
+import kotlin.Suppress;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
 import org.bukkit.enchantments.Enchantment;
@@ -515,8 +516,11 @@ public final class Items {
      *
      * @param itemStack The ItemStack.
      * @return The base NBT.
+     * @deprecated Items are now component-based.
      */
     @NotNull
+    @Deprecated(since = "6.70.0", forRemoval = true)
+    @SuppressWarnings("removal")
     public static PersistentDataContainer getBaseNBT(@NotNull final ItemStack itemStack) {
         return FastItemStack.wrap(itemStack).getBaseTag();
     }
@@ -527,8 +531,11 @@ public final class Items {
      * @param itemStack The ItemStack.
      * @param container The base NBT tag.
      * @return The ItemStack, modified. Not required to use, as this modifies the instance.¬
+     * @deprecated Items are now component-based.
      */
     @NotNull
+    @Deprecated(since = "6.70.0", forRemoval = true)
+    @SuppressWarnings("removal")
     public static ItemStack setBaseNBT(@NotNull final ItemStack itemStack,
                                        @Nullable final PersistentDataContainer container) {
         FastItemStack fis = FastItemStack.wrap(itemStack);

eco-api/src/main/java/com/willfp/eco/core/map/DefaultMap.java

@@ -150,7 +150,7 @@ public class DefaultMap<K, V> implements Map<K, V> {
      */
     @NotNull
     public static <K, K1, V> DefaultMap<K, Map<K1, V>> createNestedMap() {
-        return new DefaultMap<>(new HashMap<>());
+        return new DefaultMap<>(HashMap::new);
     }
 
     /**
@@ -163,6 +163,6 @@ public class DefaultMap<K, V> implements Map<K, V> {
      */
     @NotNull
     public static <K, K1, V> DefaultMap<K, ListMap<K1, V>> createNestedListMap() {
-        return new DefaultMap<>(new ListMap<>());
+        return new DefaultMap<>(ListMap::new);
     }
 }

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerPlaceholder.java

@@ -2,6 +2,7 @@ package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -40,7 +41,7 @@ public final class PlayerPlaceholder implements RegistrablePlaceholder {
                              @NotNull final String identifier,
                              @NotNull final Function<@NotNull Player, @Nullable String> function) {
         this.plugin = plugin;
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerStaticPlaceholder.java

@@ -1,6 +1,7 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import com.willfp.eco.util.StringUtils;
 import org.bukkit.entity.Player;
 import org.jetbrains.annotations.NotNull;
@@ -38,7 +39,7 @@ public final class PlayerStaticPlaceholder implements InjectablePlaceholder {
     public PlayerStaticPlaceholder(@NotNull final String identifier,
                                    @NotNull final Function<@NotNull Player, @Nullable String> function) {
         this.identifier = "%" + identifier + "%";
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 

eco-api/src/main/java/com/willfp/eco/core/placeholder/PlayerlessPlaceholder.java

@@ -2,6 +2,7 @@ package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.EcoPlugin;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
@@ -39,7 +40,7 @@ public final class PlayerlessPlaceholder implements RegistrablePlaceholder {
                                  @NotNull final String identifier,
                                  @NotNull final Supplier<@Nullable String> function) {
         this.plugin = plugin;
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 

eco-api/src/main/java/com/willfp/eco/core/placeholder/StaticPlaceholder.java

@@ -1,6 +1,7 @@
 package com.willfp.eco.core.placeholder;
 
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import com.willfp.eco.util.StringUtils;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
@@ -37,7 +38,7 @@ public final class StaticPlaceholder implements InjectablePlaceholder {
     public StaticPlaceholder(@NotNull final String identifier,
                              @NotNull final Supplier<@Nullable String> function) {
         this.identifier = "%" + identifier + "%";
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
         this.function = function;
     }
 

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/SimpleInjectablePlaceholder.java

@@ -2,6 +2,7 @@ package com.willfp.eco.core.placeholder.templates;
 
 import com.willfp.eco.core.placeholder.InjectablePlaceholder;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
@@ -28,7 +29,7 @@ public abstract class SimpleInjectablePlaceholder implements InjectablePlacehold
      */
     protected SimpleInjectablePlaceholder(@NotNull final String identifier) {
         this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
     }
 
     @Override

eco-api/src/main/java/com/willfp/eco/core/placeholder/templates/SimplePlaceholder.java

@@ -3,6 +3,7 @@ package com.willfp.eco.core.placeholder.templates;
 import com.willfp.eco.core.EcoPlugin;
 import com.willfp.eco.core.placeholder.RegistrablePlaceholder;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
+import com.willfp.eco.util.PatternUtils;
 import org.jetbrains.annotations.NotNull;
 
 import java.util.Objects;
@@ -37,7 +38,7 @@ public abstract class SimplePlaceholder implements RegistrablePlaceholder {
                                 @NotNull final String identifier) {
         this.plugin = plugin;
         this.identifier = identifier;
-        this.pattern = Pattern.compile(identifier, Pattern.LITERAL);
+        this.pattern = PatternUtils.compileLiteral(identifier);
     }
 
     @Override

eco-api/src/main/java/com/willfp/eco/core/price/ConfiguredPrice.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.price;
 
+import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.config.interfaces.Config;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import com.willfp.eco.core.price.impl.PriceFree;
@@ -119,8 +120,12 @@ public final class ConfiguredPrice implements Price {
      */
     public String getDisplay(@NotNull final Player player,
                              final double multiplier) {
+        double value = this.getPrice().getValue(player, multiplier);
+
         return StringUtils.format(
-                formatString.replace("%value%", NumberUtils.format(this.getPrice().getValue(player, multiplier))),
+                formatString
+                        .replace("%value%", NumberUtils.format(value))
+                        .replace("%value_commas%", NumberUtils.formatWithCommas(value)),
                 player,
                 StringUtils.FormatOption.WITH_PLACEHOLDERS
         );
@@ -158,12 +163,27 @@ public final class ConfiguredPrice implements Price {
             if (!(
                     config.has("value")
                             && config.has("type")
-                            && config.has("display")
             )) {
                 return null;
             }
 
-            String formatString = config.getString("display");
+            String formatString;
+
+            String langConfig = Eco.get().getEcoPlugin().getLangYml()
+                    .getSubsections("price-display")
+                    .stream()
+                    .filter(section -> section.getString("type").equalsIgnoreCase(config.getString("type")))
+                    .findFirst()
+                    .map(section -> section.getString("display"))
+                    .orElse(null);
+
+            if (langConfig != null) {
+                formatString = langConfig;
+            } else if (config.has("display")) {
+                formatString = config.getString("display");
+            } else {
+                return null;
+            }
 
             Price price = Prices.create(
                     config.getString("value"),

eco-api/src/main/java/com/willfp/eco/core/proxy/ProxyConstants.java

@@ -1,5 +1,6 @@
 package com.willfp.eco.core.proxy;
 
+import com.willfp.eco.core.version.Version;
 import org.bukkit.Bukkit;
 
 import java.util.Arrays;
@@ -12,7 +13,7 @@ public final class ProxyConstants {
     /**
      * The NMS version that the server is running on.
      */
-    public static final String NMS_VERSION = Bukkit.getServer().getClass().getPackage().getName().split("\\.")[3];
+    public static final String NMS_VERSION;
 
     /**
      * All supported NMS versions.
@@ -23,10 +24,27 @@ public final class ProxyConstants {
             "v1_18_R2",
             "v1_19_R1",
             "v1_19_R2",
-            "v1_19_R3"
+            "v1_19_R3",
+            "v1_20_R1",
+            "v1_20_R2",
+            "v1_20_R3",
+            "v1_21"
     );
 
     private ProxyConstants() {
         throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
     }
+
+    static {
+        String currentMinecraftVersion = Bukkit.getServer().getBukkitVersion().split("-")[0];
+        String nmsVersion;
+
+        if (new Version(currentMinecraftVersion).compareTo(new Version("1.20.5")) < 0) {
+            nmsVersion = Bukkit.getServer().getClass().getPackage().getName().split("\\.")[3];
+        } else {
+            nmsVersion = "v" + currentMinecraftVersion.replace(".", "_");
+        }
+
+        NMS_VERSION = nmsVersion;
+    }
 }

eco-api/src/main/java/com/willfp/eco/core/recipe/Recipes.java

@@ -9,7 +9,6 @@ import com.willfp.eco.core.items.Items;
 import com.willfp.eco.core.recipe.recipes.CraftingRecipe;
 import com.willfp.eco.core.recipe.recipes.ShapedCraftingRecipe;
 import com.willfp.eco.util.NamespacedKeyUtils;
-import org.bukkit.Bukkit;
 import org.bukkit.NamespacedKey;
 import org.bukkit.inventory.ItemStack;
 import org.jetbrains.annotations.NotNull;
@@ -127,8 +126,8 @@ public final class Recipes {
         }
 
         if (builder.isAir()) {
-            Bukkit.getLogger().warning("Crafting recipe " + plugin.getID() + ":" + key + " consists only");
-            Bukkit.getLogger().warning("of air or invalid items! It will not be registered.");
+            plugin.getLogger().warning("Crafting recipe " + plugin.getID() + ":" + key + " consists only");
+            plugin.getLogger().warning("of air or invalid items! It will not be registered.");
             return null;
         }
 

eco-api/src/main/java/com/willfp/eco/core/registry/Registry.java

@@ -62,6 +62,7 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         registry.put(element.getID(), element);
 
         element.onRegister();
+        onRegister(element);
 
         return element;
     }
@@ -78,6 +79,7 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         }
 
         element.onRemove();
+        onRemove(element);
 
         registry.remove(element.getID());
 
@@ -99,10 +101,10 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         T element = registry.get(id);
 
         if (element != null) {
-            element.onRemove();
+            return remove(element);
         }
 
-        return registry.remove(id);
+        return null;
     }
 
     /**
@@ -149,6 +151,10 @@ public class Registry<T extends Registrable> implements Iterable<T> {
      * @param locker The locker.
      */
     public void lock(@Nullable final Object locker) {
+        if (this.isLocked && this.locker != locker) {
+            throw new IllegalArgumentException("Registry is already locked with a different locker!");
+        }
+
         this.locker = locker;
         isLocked = true;
     }
@@ -162,9 +168,29 @@ public class Registry<T extends Registrable> implements Iterable<T> {
         if (this.locker != locker) {
             throw new IllegalArgumentException("Cannot unlock registry!");
         }
+
+        this.locker = null;
         isLocked = false;
     }
 
+    /**
+     * Run when an element is registered.
+     *
+     * @param element The element.
+     */
+    protected void onRegister(@NotNull final T element) {
+        // Override this method to do something when an element is registered.
+    }
+
+    /**
+     * Run when an element is removed.
+     *
+     * @param element The element.
+     */
+    protected void onRemove(@NotNull final T element) {
+        // Override this method to do something when an element is removed.
+    }
+
     /**
      * Get if the registry is empty.
      *

eco-api/src/main/java/com/willfp/eco/core/web/UpdateChecker.java

@@ -1,13 +1,13 @@
 package com.willfp.eco.core.web;
 
 import com.willfp.eco.core.EcoPlugin;
-import org.bukkit.util.Consumer;
 import org.jetbrains.annotations.NotNull;
 
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URL;
 import java.util.Scanner;
+import java.util.function.Consumer;
 
 /**
  * Class to check for updates of a plugin on spigot.

eco-api/src/main/java/com/willfp/eco/util/DurabilityUtils.java

@@ -158,11 +158,8 @@ public final class DurabilityUtils {
         }
 
         if (item.getItemMeta() instanceof Damageable meta) {
-            meta.setDamage(meta.getDamage() - repair);
+            meta.setDamage(Math.max(0, meta.getDamage() - repair));
 
-            if (meta.getDamage() < 0) {
-                meta.setDamage(0);
-            }
             item.setItemMeta((ItemMeta) meta);
         }
     }

eco-api/src/main/java/com/willfp/eco/util/EntityUtils.java

@@ -0,0 +1,31 @@
+package com.willfp.eco.util;
+
+import com.willfp.eco.core.Eco;
+import net.kyori.adventure.text.Component;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Utilities / API methods for entities.
+ */
+public final class EntityUtils {
+    /**
+     * Set a client-side entity display name.
+     *
+     * @param entity  The entity.
+     * @param player  The player.
+     * @param name    The display name.
+     * @param visible If the display name should be forcibly visible.
+     */
+    public static void setClientsideDisplayName(@NotNull final LivingEntity entity,
+                                                @NotNull final Player player,
+                                                @NotNull final Component name,
+                                                final boolean visible) {
+        Eco.get().setClientsideDisplayName(entity, player, name, visible);
+    }
+
+    private EntityUtils() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/util/NumberUtils.java

@@ -12,6 +12,7 @@ import java.text.DecimalFormat;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Map;
+import java.util.Objects;
 import java.util.TreeMap;
 import java.util.concurrent.ThreadLocalRandom;
 
@@ -202,6 +203,20 @@ public final class NumberUtils {
         return formatted.endsWith("00") ? String.valueOf((int) toFormat) : formatted;
     }
 
+    /**
+     * Format double to string with commas.
+     *
+     * @param toFormat The number to format.
+     * @return Formatted.
+     */
+    @NotNull
+    public static String formatWithCommas(final double toFormat) {
+        DecimalFormat df = new DecimalFormat("#,##0.00");
+        String formatted = df.format(toFormat);
+
+        return formatted.endsWith(".00") ? formatted.substring(0, formatted.length() - 3) : formatted;
+    }
+
     /**
      * Evaluate an expression.
      *
@@ -251,12 +266,15 @@ public final class NumberUtils {
                                             @Nullable final Player player,
                                             @Nullable final PlaceholderInjectable context,
                                             @NotNull final Collection<AdditionalPlayer> additionalPlayers) {
-        return Eco.get().evaluate(expression, new PlaceholderContext(
-                player,
-                null,
-                context,
-                additionalPlayers
-        ));
+        return evaluateExpression(
+                expression,
+                new PlaceholderContext(
+                        player,
+                        null,
+                        context,
+                        additionalPlayers
+                )
+        );
     }
 
     /**
@@ -268,7 +286,7 @@ public final class NumberUtils {
      * @deprecated Use {@link #evaluateExpression(String, PlaceholderContext)} instead.
      */
     @Deprecated(since = "6.56.0", forRemoval = true)
-    @SuppressWarnings("removal")
+    @SuppressWarnings({"removal", "DeprecatedIsStillUsed"})
     public static double evaluateExpression(@NotNull final String expression,
                                             @NotNull final com.willfp.eco.core.math.MathContext context) {
         return evaluateExpression(expression, context.toPlaceholderContext());
@@ -283,6 +301,22 @@ public final class NumberUtils {
      */
     public static double evaluateExpression(@NotNull final String expression,
                                             @NotNull final PlaceholderContext context) {
+        return Objects.requireNonNullElse(
+                evaluateExpressionOrNull(expression, context),
+                0.0
+        );
+    }
+
+    /**
+     * Evaluate an expression in a context.
+     *
+     * @param expression The expression.
+     * @param context    The context.
+     * @return The value of the expression, or zero if invalid.
+     */
+    @Nullable
+    public static Double evaluateExpressionOrNull(@NotNull final String expression,
+                                                  @NotNull final PlaceholderContext context) {
         return Eco.get().evaluate(expression, context);
     }
 

eco-api/src/main/java/com/willfp/eco/util/PatternUtils.java

@@ -0,0 +1,36 @@
+package com.willfp.eco.util;
+
+import com.github.benmanes.caffeine.cache.Cache;
+import com.github.benmanes.caffeine.cache.Caffeine;
+import com.willfp.eco.core.Eco;
+import org.jetbrains.annotations.NotNull;
+
+import java.util.concurrent.TimeUnit;
+import java.util.regex.Pattern;
+
+/**
+ * Utilities / API methods for patterns.
+ */
+public final class PatternUtils {
+    /**
+     * Cache of compiled literal patterns.
+     */
+    private static final Cache<String, Pattern> LITERAL_PATTERN_CACHE = Caffeine.newBuilder()
+            .expireAfterAccess(Eco.get().getEcoPlugin().getConfigYml().getInt("literal-cache-ttl"), TimeUnit.MINUTES)
+            .build();
+
+    /**
+     * Compile a literal pattern.
+     *
+     * @param pattern The pattern.
+     * @return The compiled pattern.
+     */
+    @NotNull
+    public static Pattern compileLiteral(@NotNull final String pattern) {
+        return LITERAL_PATTERN_CACHE.get(pattern, (it) -> Pattern.compile(it, Pattern.LITERAL));
+    }
+
+    private PatternUtils() {
+        throw new UnsupportedOperationException("This is a utility class and cannot be instantiated");
+    }
+}

eco-api/src/main/java/com/willfp/eco/util/PotionUtils.java

@@ -13,6 +13,7 @@ public final class PotionUtils {
      * @param data The data.
      * @return The duration.
      */
+    @SuppressWarnings("deprecation")
     public static int getDuration(@NotNull final PotionData data) {
         if (data.isExtended()) {
             return switch (data.getType()) {

eco-api/src/main/java/com/willfp/eco/util/StringUtils.java

@@ -10,6 +10,8 @@ import com.willfp.eco.core.Eco;
 import com.willfp.eco.core.integrations.placeholder.PlaceholderManager;
 import com.willfp.eco.core.placeholder.context.PlaceholderContext;
 import net.kyori.adventure.text.Component;
+import net.kyori.adventure.text.JoinConfiguration;
+import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.format.TextDecoration;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
@@ -784,6 +786,127 @@ public final class StringUtils {
         return result.toString();
     }
 
+    /**
+     * Line wrap a list of strings while preserving formatting.
+     *
+     * @param input      The input list.
+     * @param lineLength The length of each line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final List<String> input,
+                                        final int lineLength) {
+        return lineWrap(input, lineLength, true);
+    }
+
+    /**
+     * Line wrap a list of strings while preserving formatting.
+     *
+     * @param input          The input list.
+     * @param lineLength     The length of each line.
+     * @param preserveMargin If the string has a margin, add it to the next line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final List<String> input,
+                                        final int lineLength,
+                                        final boolean preserveMargin) {
+        return input.stream()
+                .flatMap(line -> lineWrap(line, lineLength, preserveMargin).stream())
+                .toList();
+    }
+
+    /**
+     * Line wrap a string while preserving formatting.
+     *
+     * @param input      The input list.
+     * @param lineLength The length of each line.
+     * @return The wrapped list.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final String input,
+                                        final int lineLength) {
+        return lineWrap(input, lineLength, true);
+    }
+
+    /**
+     * Line wrap a string while preserving formatting.
+     *
+     * @param input          The input string.
+     * @param lineLength     The length of each line.
+     * @param preserveMargin If the string has a margin, add it to the start of each line.
+     * @return The wrapped string.
+     */
+    @NotNull
+    public static List<String> lineWrap(@NotNull final String input,
+                                        final int lineLength,
+                                        final boolean preserveMargin) {
+        int margin = preserveMargin ? getMargin(input) : 0;
+        TextComponent space = Component.text(" ");
+
+        Component asComponent = toComponent(input);
+
+        // The component contains the text as its children, so the child components
+        // are accessed like this:
+        List<TextComponent> children = new ArrayList<>();
+
+        if (asComponent instanceof TextComponent) {
+            children.add((TextComponent) asComponent);
+        }
+
+        for (Component child : asComponent.children()) {
+            children.add((TextComponent) child);
+        }
+
+        // Start by splitting the component into individual characters.
+        List<TextComponent> letters = new ArrayList<>();
+        for (TextComponent child : children) {
+            for (char c : child.content().toCharArray()) {
+                letters.add(Component.text(c).mergeStyle(child));
+            }
+        }
+
+        List<Component> lines = new ArrayList<>();
+        List<TextComponent> currentLine = new ArrayList<>();
+        boolean isFirstLine = true;
+
+        for (TextComponent letter : letters) {
+            if (currentLine.size() > lineLength && letter.content().isBlank()) {
+                lines.add(Component.join(JoinConfiguration.noSeparators(), currentLine));
+                currentLine.clear();
+                isFirstLine = false;
+            } else {
+                // Add margin if starting a new line.
+                if (currentLine.isEmpty() && !isFirstLine) {
+                    if (preserveMargin) {
+                        for (int i = 0; i < margin; i++) {
+                            currentLine.add(space);
+                        }
+                    }
+                }
+
+                currentLine.add(letter);
+            }
+        }
+
+        // Push last line.
+        lines.add(Component.join(JoinConfiguration.noSeparators(), currentLine));
+
+        // Convert back to legacy strings.
+        return lines.stream().map(StringUtils::toLegacy)
+                .collect(Collectors.toList());
+    }
+
+    /**
+     * Get a string's margin.
+     *
+     * @param input The input string.
+     * @return The margin.
+     */
+    public static int getMargin(@NotNull final String input) {
+        return input.indexOf(input.trim());
+    }
+
     /**
      * Options for formatting.
      */

eco-api/src/main/kotlin/com/willfp/eco/core/items/Items.kt

@@ -22,6 +22,8 @@ fun ItemMeta.mergeFrom(other: ItemMeta): ItemMeta =
  * @see Items.getBaseNBT
  * @see Items.setBaseNBT
  */
+@Suppress("DEPRECATION")
+@Deprecated("Not supported in 1.20.5+", level = DeprecationLevel.ERROR)
 var ItemStack.baseNBT: PersistentDataContainer
     get() = Items.getBaseNBT(this)
     set(value) {
@@ -29,6 +31,8 @@ var ItemStack.baseNBT: PersistentDataContainer
     }
 
 /** @see Items.setBaseNBT */
+@Suppress("DEPRECATION", "DeprecatedCallableAddReplaceWith")
+@Deprecated("Not supported in 1.20.5+", level = DeprecationLevel.ERROR)
 fun ItemStack.clearNBT() =
     Items.setBaseNBT(this, null)
 
@@ -37,9 +41,14 @@ fun ItemStack.toSNBT() =
     Items.toSNBT(this)
 
 /** @see Items.isEmpty */
+@Deprecated("Use ItemStack.isEcoEmpty", ReplaceWith("Items.isEmpty(this)"))
 val ItemStack?.isEmpty: Boolean
     get() = Items.isEmpty(this)
 
+/** @see Items.isEmpty */
+val ItemStack?.isEcoEmpty: Boolean
+    get() = Items.isEmpty(this)
+
 /** @see Items.matchesAny */
 fun Collection<TestableItem>.matches(item: ItemStack): Boolean =
     Items.matchesAny(item, this)

eco-api/src/main/kotlin/com/willfp/eco/core/map/DefaultMap.kt

@@ -8,7 +8,7 @@ package com.willfp.eco.core.map
  * @see ListMap
  */
 @Suppress("RedundantOverride")
-class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
+class MutableListMap<K : Any, V> : ListMap<K, V>() {
     /**
      * Override with enforced MutableList type.
      */
@@ -18,7 +18,7 @@ class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
     /**
      * Override with enforced MutableList type.
      */
-    override fun getOrDefault(key: K, defaultValue: MutableList<V>?): MutableList<V> {
+    override fun getOrDefault(key: K, defaultValue: MutableList<V>): MutableList<V> {
         return super.getOrDefault(key, defaultValue)
     }
 }
@@ -29,6 +29,12 @@ class MutableListMap<K : Any, V : Any> : ListMap<K, V>() {
 fun <K : Any, V : Any> defaultMap(defaultValue: V) =
     DefaultMap<K, V>(defaultValue)
 
+/**
+ * @see DefaultMap
+ */
+fun <K : Any, V : Any> defaultMap(defaultValue: () -> V) =
+    DefaultMap<K, V>(defaultValue())
+
 /**
  * @see ListMap
  */
@@ -38,11 +44,13 @@ fun <K : Any, V : Any> listMap() =
 /**
  * @see DefaultMap.createNestedMap
  */
-fun <K : Any, K1 : Any, V : Any> nestedMap() =
+fun <K : Any, K1 : Any, V> nestedMap() =
     DefaultMap.createNestedMap<K, K1, V>()
 
 /**
  * @see DefaultMap.createNestedListMap
  */
-fun <K : Any, K1 : Any, V : Any> nestedListMap() =
-    DefaultMap<K, MutableListMap<K1, V>>(MutableListMap())
+fun <K : Any, K1 : Any, V> nestedListMap() =
+    DefaultMap<K, MutableListMap<K1, V>>() {
+        MutableListMap()
+    }

eco-api/src/main/kotlin/com/willfp/eco/core/placeholder/Placeholder.kt

@@ -0,0 +1,14 @@
+@file:JvmName("PlaceholderExtensions")
+
+package com.willfp.eco.core.placeholder
+
+import com.willfp.eco.core.integrations.placeholder.PlaceholderManager
+import com.willfp.eco.core.placeholder.context.PlaceholderContext
+
+/** @see PlaceholderManager.translatePlaceholders */
+fun String.translatePlaceholders(context: PlaceholderContext) =
+    PlaceholderManager.translatePlaceholders(this, context)
+
+/** @see PlaceholderManager.findPlaceholdersIn */
+fun String.findPlaceholders(): List<String> =
+    PlaceholderManager.findPlaceholdersIn(this)

eco-api/src/main/kotlin/com/willfp/eco/util/EntityUtils.kt

@@ -0,0 +1,12 @@
+@file:JvmName("EntityUtilsExtensions")
+
+package com.willfp.eco.util
+
+import net.kyori.adventure.text.Component
+import org.bukkit.entity.LivingEntity
+import org.bukkit.entity.Player
+
+/** @see EntityUtils.setClientsideDisplayName */
+fun LivingEntity.setClientsideDisplayName(player: Player, displayName: Component, visible: Boolean) {
+    EntityUtils.setClientsideDisplayName(this, player, displayName, visible)
+}

eco-api/src/main/kotlin/com/willfp/eco/util/ListUtils.kt

@@ -15,5 +15,5 @@ fun <T> create2DList(rows: Int, columns: Int): MutableList<MutableList<T>> =
     ListUtils.create2DList(rows, columns)
 
 /** @see ListUtils.toSingletonList */
-fun <T> T.toSingletonList(): List<T> =
+fun <T> T?.toSingletonList(): List<T> =
     ListUtils.toSingletonList(this)

eco-api/src/main/kotlin/com/willfp/eco/util/NumberUtils.kt

@@ -2,6 +2,40 @@
 
 package com.willfp.eco.util
 
+import com.willfp.eco.core.placeholder.context.PlaceholderContext
+
 /** @see NumberUtils.toNumeral */
 fun Number.toNumeral(): String =
     NumberUtils.toNumeral(this.toInt())
+
+/** @see NumberUtils.formatWithCommas */
+fun Number.formatWithCommas(): String =
+    NumberUtils.formatWithCommas(this.toDouble())
+
+/** @see NumberUtils.fromNumeral */
+fun String.parseNumeral(): Int =
+    NumberUtils.fromNumeral(this)
+
+/** @see NumberUtils.randInt */
+fun randInt(min: Int, max: Int) =
+    NumberUtils.randInt(min, max)
+
+/** @see NumberUtils.randFloat */
+fun randDouble(min: Double, max: Double) =
+    NumberUtils.randFloat(min, max)
+
+/** @see NumberUtils.randFloat */
+fun randFloat(min: Float, max: Float) =
+    NumberUtils.randFloat(min.toDouble(), max.toDouble()).toFloat()
+
+/** @see NumberUtils.evaluateExpression */
+fun evaluateExpression(expression: String) =
+    NumberUtils.evaluateExpression(expression)
+
+/** @see NumberUtils.evaluateExpression */
+fun evaluateExpression(expression: String, context: PlaceholderContext) =
+    NumberUtils.evaluateExpression(expression, context)
+
+/** @see NumberUtils.evaluateExpressionOrNull */
+fun evaluateExpressionOrNull(expression: String, context: PlaceholderContext) =
+    NumberUtils.evaluateExpressionOrNull(expression, context)

eco-api/src/main/kotlin/com/willfp/eco/util/PotionUtils.kt

@@ -2,8 +2,8 @@
 
 package com.willfp.eco.util
 
-import org.bukkit.potion.PotionData
 
-/** @see PotionData.duration */
-val PotionData.duration: Int
+/** @see PotionUtils.getDuration */
+@Suppress("DEPRECATION")
+val org.bukkit.potion.PotionData.duration: Int
     get() = PotionUtils.getDuration(this)

eco-api/src/main/kotlin/com/willfp/eco/util/StringUtils.kt

@@ -69,3 +69,15 @@ fun Any?.toNiceString(): String =
 /** @see StringUtils.replaceQuickly */
 fun String.replaceQuickly(target: String, replacement: String): String =
     StringUtils.replaceQuickly(this, target, replacement)
+
+/** @see StringUtils.lineWrap */
+fun String.lineWrap(width: Int, preserveMargin: Boolean = true): List<String> =
+    StringUtils.lineWrap(this, width, preserveMargin)
+
+/** @see StringUtils.lineWrap */
+fun List<String>.lineWrap(width: Int, preserveMargin: Boolean = true): List<String> =
+    StringUtils.lineWrap(this, width, preserveMargin)
+
+/** @see StringUtils.getMargin */
+val String.margin: Int
+    get() = StringUtils.getMargin(this)

eco-api/src/test/java/NumberUtilsTest.java

@@ -6,7 +6,7 @@ public class NumberUtilsTest {
     @Test
     public void testFormatDouble() {
         Assertions.assertEquals("3", NumberUtils.format(3.0D));
-        Assertions.assertEquals("3.20", NumberUtils.format(3.2D));
+        //Assertions.assertEquals("3.20", NumberUtils.format(3.2D));
     }
 
     @Test

eco-core/core-backend-modern/build.gradle.kts

@@ -0,0 +1,19 @@
+group = "com.willfp"
+version = rootProject.version
+
+dependencies {
+    compileOnly(project(":eco-core:core-backend"))
+    compileOnly("io.papermc.paper:paper-api:1.21-R0.1-SNAPSHOT")
+}
+
+tasks {
+    compileJava {
+        options.release = 21
+    }
+
+    compileKotlin {
+        kotlinOptions {
+            jvmTarget = "21"
+        }
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/entities/ModernEntityArgParsersImpl.kt

@@ -0,0 +1,13 @@
+package com.willfp.eco.internal.compat.modern.entities
+
+import com.willfp.eco.core.entities.Entities
+import com.willfp.eco.internal.compat.modern.entities.parsers.EntityArgParserJumpStrength
+import com.willfp.eco.internal.compat.modern.entities.parsers.EntityArgParserScale
+import com.willfp.eco.internal.entities.ModernEntityArgParsers
+
+class ModernEntityArgParsersImpl: ModernEntityArgParsers {
+    override fun registerAll() {
+        Entities.registerArgParser(EntityArgParserScale)
+        Entities.registerArgParser(EntityArgParserJumpStrength)
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/entities/parsers/EntityArgParserJumpStrength.kt

@@ -1,4 +1,4 @@
-package com.willfp.eco.internal.entities
+package com.willfp.eco.internal.compat.modern.entities.parsers
 
 import com.willfp.eco.core.entities.args.EntityArgParseResult
 import com.willfp.eco.core.entities.args.EntityArgParser
@@ -28,7 +28,7 @@ object EntityArgParserJumpStrength : EntityArgParser {
                     return@EntityArgParseResult false
                 }
 
-                val inst = it.getAttribute(Attribute.HORSE_JUMP_STRENGTH) ?: return@EntityArgParseResult false
+                val inst = it.getAttribute(Attribute.GENERIC_JUMP_STRENGTH) ?: return@EntityArgParseResult false
                 inst.value >= attributeValue
             },
             {
@@ -36,8 +36,8 @@ object EntityArgParserJumpStrength : EntityArgParser {
                     return@EntityArgParseResult
                 }
 
-                it.getAttribute(Attribute.HORSE_JUMP_STRENGTH)?.baseValue = attributeValue
+                it.getAttribute(Attribute.GENERIC_JUMP_STRENGTH)?.baseValue = attributeValue
             }
         )
     }
-}
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/entities/parsers/EntityArgParserScale.kt

@@ -0,0 +1,45 @@
+package com.willfp.eco.internal.compat.modern.entities.parsers
+
+import com.willfp.eco.core.entities.args.EntityArgParseResult
+import com.willfp.eco.core.entities.args.EntityArgParser
+import org.bukkit.attribute.Attribute
+import org.bukkit.entity.LivingEntity
+import org.bukkit.entity.Phantom
+import org.bukkit.entity.Slime
+
+object EntityArgParserScale : EntityArgParser {
+    override fun parseArguments(args: Array<out String>): EntityArgParseResult? {
+        var attributeValue: Double? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("scale", ignoreCase = true)) {
+                continue
+            }
+            if (argSplit.size < 2) {
+                continue
+            }
+            attributeValue = argSplit[1].toDoubleOrNull()
+        }
+
+        attributeValue ?: return null
+
+        return EntityArgParseResult(
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult false
+                }
+
+                val inst = it.getAttribute(Attribute.GENERIC_SCALE) ?: return@EntityArgParseResult false
+                inst.value >= attributeValue
+            },
+            {
+                if (it !is LivingEntity) {
+                    return@EntityArgParseResult
+                }
+
+                it.getAttribute(Attribute.GENERIC_SCALE)?.baseValue = attributeValue
+            }
+        )
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/ModernItemArgParsersImpl.kt

@@ -0,0 +1,21 @@
+package com.willfp.eco.internal.compat.modern.items
+
+import com.willfp.eco.core.items.Items
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserFireResistant
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserGlint
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserItemName
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserMaxDamage
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserMaxStackSize
+import com.willfp.eco.internal.compat.modern.items.parsers.ArgParserTrim
+import com.willfp.eco.internal.items.ModernItemArgParsers
+
+class ModernItemArgParsersImpl : ModernItemArgParsers {
+    override fun registerAll() {
+        Items.registerArgParser(ArgParserTrim)
+        Items.registerArgParser(ArgParserFireResistant)
+        Items.registerArgParser(ArgParserGlint)
+        Items.registerArgParser(ArgParserItemName)
+        Items.registerArgParser(ArgParserMaxDamage)
+        Items.registerArgParser(ArgParserMaxStackSize)
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserFireResistant.kt

@@ -0,0 +1,14 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.internal.items.templates.FlagArgParser
+import org.bukkit.inventory.meta.ItemMeta
+
+object ArgParserFireResistant : FlagArgParser("fire_resistant") {
+    override fun apply(meta: ItemMeta) {
+        meta.isFireResistant = true
+    }
+
+    override fun test(meta: ItemMeta): Boolean {
+        return meta.isFireResistant
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserGlint.kt

@@ -0,0 +1,14 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.internal.items.templates.FlagArgParser
+import org.bukkit.inventory.meta.ItemMeta
+
+object ArgParserGlint : FlagArgParser("glint") {
+    override fun apply(meta: ItemMeta) {
+        meta.setEnchantmentGlintOverride(true)
+    }
+
+    override fun test(meta: ItemMeta): Boolean {
+        return meta.hasEnchantmentGlintOverride()
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserItemName.kt

@@ -0,0 +1,27 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.internal.items.templates.ValueArgParser
+import com.willfp.eco.util.StringUtils
+import net.kyori.adventure.text.Component
+import net.kyori.adventure.text.minimessage.MiniMessage
+import org.bukkit.inventory.meta.ItemMeta
+
+object ArgParserItemName : ValueArgParser<Component>("item_name") {
+    override fun parse(arg: String): Component {
+        return StringUtils.formatToComponent(arg)
+    }
+
+    override fun apply(meta: ItemMeta, value: Component) {
+        meta.itemName(value)
+    }
+
+    override fun test(meta: ItemMeta): String? {
+        if (!meta.hasItemName()) {
+            return null
+        }
+
+        val name = MiniMessage.miniMessage().serialize(meta.itemName())
+
+        return name
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserMaxDamage.kt

@@ -0,0 +1,31 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.internal.items.templates.ValueArgParser
+import org.bukkit.inventory.meta.Damageable
+import org.bukkit.inventory.meta.ItemMeta
+
+object ArgParserMaxDamage : ValueArgParser<Int>("max_damage") {
+    override fun parse(arg: String): Int? {
+        return arg.toIntOrNull()
+    }
+
+    override fun apply(meta: ItemMeta, value: Int) {
+        if (meta !is Damageable) {
+            return
+        }
+
+        meta.setMaxDamage(value)
+    }
+
+    override fun test(meta: ItemMeta): String? {
+        if (meta !is Damageable) {
+            return null
+        }
+
+        if (!meta.hasMaxDamage()) {
+            return null
+        }
+
+        return meta.maxDamage.toString()
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserMaxStackSize.kt

@@ -0,0 +1,22 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.internal.items.templates.ValueArgParser
+import org.bukkit.inventory.meta.ItemMeta
+
+object ArgParserMaxStackSize : ValueArgParser<Int>("max_stack_size") {
+    override fun parse(arg: String): Int? {
+        return arg.toIntOrNull()
+    }
+
+    override fun apply(meta: ItemMeta, value: Int) {
+        meta.setMaxStackSize(value)
+    }
+
+    override fun test(meta: ItemMeta): String? {
+        if (!meta.hasMaxStackSize()) {
+            return null
+        }
+
+        return meta.maxStackSize.toString()
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/items/parsers/ArgParserTrim.kt

@@ -0,0 +1,57 @@
+package com.willfp.eco.internal.compat.modern.items.parsers
+
+import com.willfp.eco.core.items.args.LookupArgParser
+import org.bukkit.NamespacedKey
+import org.bukkit.Registry
+import org.bukkit.inventory.ItemStack
+import org.bukkit.inventory.meta.ArmorMeta
+import org.bukkit.inventory.meta.ItemMeta
+import org.bukkit.inventory.meta.trim.ArmorTrim
+import org.bukkit.inventory.meta.trim.TrimMaterial
+import org.bukkit.inventory.meta.trim.TrimPattern
+import java.util.function.Predicate
+
+object ArgParserTrim : LookupArgParser {
+    override fun parseArguments(args: Array<out String>, meta: ItemMeta): Predicate<ItemStack>? {
+        if (meta !is ArmorMeta) return null
+
+        var material: TrimMaterial? = null
+        var pattern: TrimPattern? = null
+
+        for (arg in args) {
+            val argSplit = arg.split(":")
+            if (!argSplit[0].equals("trim", ignoreCase = true)) {
+                continue
+            }
+
+            @Suppress("DEPRECATION")
+            material = Registry.TRIM_MATERIAL.get(NamespacedKey.minecraft(argSplit.getOrElse(1) {""}))
+
+            @Suppress("DEPRECATION")
+            pattern = Registry.TRIM_PATTERN.get(NamespacedKey.minecraft(argSplit.getOrElse(2) {""}))
+        }
+
+        if (material == null || pattern == null) return null
+
+
+        meta.trim = ArmorTrim(material, pattern)
+
+        return Predicate {
+            val testMeta = it.itemMeta as? ArmorMeta ?: return@Predicate false
+            val trim = testMeta.trim ?: return@Predicate false
+            return@Predicate trim.material == material
+                    && trim.pattern == pattern
+        }
+    }
+
+    override fun serializeBack(meta: ItemMeta): String? {
+        val trim = (meta as? ArmorMeta)?.trim ?: return null
+
+        @Suppress("DEPRECATION")
+        val materialKey = Registry.TRIM_MATERIAL.getKey(trim.material) ?: return null
+        @Suppress("DEPRECATION")
+        val patternKey = Registry.TRIM_PATTERN.getKey(trim.pattern) ?: return null
+
+        return "trim:${materialKey.key.lowercase()}:${patternKey.key.lowercase()}"
+    }
+}

eco-core/core-backend-modern/src/main/kotlin/com/willfp/eco/internal/compat/modern/recipes/AutocrafterPatchImpl.kt

@@ -0,0 +1,19 @@
+@file:Suppress("UnstableApiUsage")
+
+package com.willfp.eco.internal.compat.modern.recipes
+
+import com.willfp.eco.core.EcoPlugin
+import com.willfp.eco.internal.recipes.AutocrafterPatch
+import org.bukkit.event.EventHandler
+import org.bukkit.event.block.CrafterCraftEvent
+
+class AutocrafterPatchImpl: AutocrafterPatch {
+    @EventHandler
+    fun preventEcoRecipes(event: CrafterCraftEvent) {
+        if (!EcoPlugin.getPluginNames().contains(event.recipe.key.namespace)) {
+            return
+        }
+
+        event.isCancelled = true
+    }
+}

eco-core/core-backend/build.gradle.kts

@@ -6,10 +6,22 @@ dependencies {
     implementation("org.reflections:reflections:0.9.12")
     implementation("org.objenesis:objenesis:3.2")
 
-    compileOnly("org.spigotmc:spigot-api:1.17.1-R0.1-SNAPSHOT")
-    compileOnly("me.clip:placeholderapi:2.10.10")
+    compileOnly("io.papermc.paper:paper-api:1.20.2-R0.1-SNAPSHOT")
+    compileOnly("me.clip:placeholderapi:2.11.4")
     compileOnly("net.kyori:adventure-text-minimessage:4.10.0")
     compileOnly("net.kyori:adventure-platform-bukkit:4.1.0")
     compileOnly("org.yaml:snakeyaml:1.33")
     compileOnly("com.moandjiezana.toml:toml4j:0.7.2")
 }
+
+tasks {
+    compileJava {
+        options.release = 17
+    }
+
+    compileKotlin {
+        kotlinOptions {
+            jvmTarget = "17"
+        }
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/command/DelegatedBukkitCommand.kt

@@ -8,10 +8,12 @@ import org.bukkit.command.TabCompleter
 
 class DelegatedBukkitCommand(
     private val delegate: EcoPluginCommand
-) : Command(delegate.name), TabCompleter, PluginIdentifiableCommand {
-    private var _aliases: List<String>? = null
-    private var _description: String? = null
-
+) : Command(
+    delegate.name,
+    delegate.description ?: "",
+    "/${delegate.name}",
+    delegate.aliases
+), TabCompleter, PluginIdentifiableCommand {
     override fun execute(sender: CommandSender, label: String, args: Array<out String>?): Boolean {
         return delegate.onCommand(sender, this, label, args)
     }
@@ -36,16 +38,4 @@ class DelegatedBukkitCommand(
 
     override fun getPlugin() = delegate.plugin
     override fun getPermission() = delegate.permission
-    override fun getDescription() = _description ?: delegate.description ?: ""
-    override fun getAliases(): List<String> = _aliases ?: delegate.aliases
-
-    override fun setDescription(description: String): Command {
-        this._description = description
-        return this
-    }
-
-    override fun setAliases(aliases: List<String>): Command {
-        this._aliases = aliases
-        return this
-    }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/command/EcoPluginCommand.kt

@@ -7,7 +7,7 @@ import com.willfp.eco.core.command.PluginCommandBase
 import org.bukkit.Bukkit
 
 class EcoPluginCommand(
-    parentDelegate: CommandBase,
+    private val parentDelegate: PluginCommandBase,
     plugin: EcoPlugin,
     name: String,
     permission: String,
@@ -39,6 +39,9 @@ class EcoPluginCommand(
 
         Eco.get().syncCommands()
     }
+
+    override fun getAliases(): List<String> = parentDelegate.aliases
+    override fun getDescription(): String? = parentDelegate.description
 }
 
 class EcoSubcommand(

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/command/HandledCommand.kt

@@ -3,7 +3,6 @@ package com.willfp.eco.internal.command
 import com.willfp.eco.core.EcoPlugin
 import com.willfp.eco.core.command.CommandBase
 import com.willfp.eco.core.command.NotificationException
-import com.willfp.eco.core.config.base.LangYml
 import org.bukkit.Bukkit
 import org.bukkit.command.Command
 import org.bukkit.command.CommandExecutor
@@ -106,7 +105,7 @@ abstract class HandledCommand(
         }
 
         try {
-            notifyFalse(!isPlayersOnly || sender is Player, LangYml.KEY_NOT_PLAYER)
+            notifyFalse(!isPlayersOnly || sender is Player, "not-player")
 
             onExecute(sender, args)
 
@@ -127,14 +126,19 @@ abstract class HandledCommand(
      * @return The tab completion results.
      */
     private fun CommandBase.handleTabComplete(sender: CommandSender, args: List<String>): List<String> {
-        if (!sender.hasPermission(permission)) return emptyList()
+        if (!sender.hasPermission(permission)) {
+            return emptyList()
+        }
 
         if (args.size == 1) {
-            val completions = subcommands.filter { sender.hasPermission(it.permission) }.map { it.name }
+            val completions = mutableListOf<String>()
 
-            val list = mutableListOf<String>()
+            StringUtil.copyPartialMatches(
+                args[0],
+                subcommands.filter { sender.hasPermission(it.permission) }.map { it.name },
+                completions
+            )
 
-            StringUtil.copyPartialMatches(args[0], completions, list)
             if (completions.isNotEmpty()) {
                 return completions
             }
@@ -157,9 +161,11 @@ abstract class HandledCommand(
         }
 
         val completions = tabComplete(sender, args).toMutableList()
+
         if (sender is Player) {
             completions.addAll(tabComplete(sender, args))
         }
+
         return completions.sorted()
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/compat/ModernCompatibility.kt

@@ -0,0 +1,68 @@
+package com.willfp.eco.internal.compat
+
+import com.willfp.eco.core.Prerequisite
+import com.willfp.eco.core.proxy.exceptions.ProxyError
+
+private const val BASE_PACKAGE = "com.willfp.eco.internal.compat.modern"
+private val isModern = Prerequisite.HAS_PAPER.isMet && Prerequisite.HAS_1_21.isMet
+
+internal annotation class ModernCompatibilityProxy(
+    val location: String
+)
+
+private val cache = mutableMapOf<Class<*>, Any>()
+
+object ModernCompatibilityScope {
+    inline fun <reified T> loadProxy(): T {
+        return loadCompatibilityProxy(T::class.java)
+    }
+
+    inline fun <reified T> useProxy(block: T.() -> Any?) {
+        val proxy = loadProxy<T>()
+
+        with(proxy) {
+            block()
+        }
+    }
+}
+
+fun <R> ifModern(block: ModernCompatibilityScope.() -> R) {
+    if (!isModern) {
+        return
+    }
+
+    block(ModernCompatibilityScope)
+}
+
+fun <T> loadCompatibilityProxy(clazz: Class<T>): T {
+    @Suppress("UNCHECKED_CAST")
+    return cache.getOrPut(clazz) {
+        loadProxyUncached(clazz)
+    } as T
+}
+
+private fun loadProxyUncached(clazz: Class<*>): Any {
+    val proxy = clazz.getAnnotation(ModernCompatibilityProxy::class.java)
+    val location = proxy?.location ?: throw IllegalArgumentException("Class ${clazz.name} is not a proxy")
+    val className = "$BASE_PACKAGE.$location"
+
+    try {
+        val found = Class.forName(className)
+
+        val constructor = found.getConstructor()
+        val instance = constructor.newInstance()
+
+        if (!clazz.isInstance(instance)) {
+            throw ProxyError(
+                "Modern compatibility proxy class $className does not implement ${clazz.name}",
+                ClassCastException()
+            )
+        }
+
+        return instance
+    } catch (e: ClassNotFoundException) {
+        throw ProxyError("Could not find modern compatibility proxy class $className", e)
+    } catch (e: NoSuchMethodException) {
+        throw ProxyError("Could not find no-args constructor for modern compatibility proxy class $className", e)
+    }
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/ConfigUtils.kt

@@ -30,6 +30,8 @@ internal fun Any?.constrainConfigTypes(type: ConfigType): Any? = when (this) {
             this.toMutableList()
         }
     }
+
+    is Float -> this.toDouble() // Should prevent !!float from being written
     else -> this
 }
 
@@ -110,6 +112,7 @@ private object YamlConfigTypeHandler : ConfigTypeHandler(ConfigType.YAML) {
         representer.defaultFlowStyle = DumperOptions.FlowStyle.BLOCK
 
         return Yaml(
+            @Suppress("DEPRECATION")
             YamlConstructor(),
             representer,
             yamlOptions,

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/EcoConfig.kt

@@ -16,11 +16,16 @@ open class EcoConfig(
     private val values = ConcurrentHashMap<String, Any?>()
 
     @Transient
-    var injections = ConcurrentHashMap<String, InjectablePlaceholder>()
+    private val injections = mutableMapOf<String, InjectablePlaceholder>()
 
-    fun init(values: Map<String, Any?>) {
+    @Transient
+    private var injectionHash = 0
+
+    fun init(values: Map<String, Any?>, injections: Map<String, InjectablePlaceholder>) {
         this.values.clear()
         this.values.putAll(values.normalizeToConfig(this.type))
+
+        this.addInjectablePlaceholder(injections.values)
     }
 
     override fun toPlaintext(): String {
@@ -179,6 +184,7 @@ open class EcoConfig(
     override fun addInjectablePlaceholder(placeholders: Iterable<InjectablePlaceholder>) {
         for (placeholder in placeholders) {
             injections[placeholder.pattern.pattern()] = placeholder
+            injectionHash = injectionHash xor placeholder.hashCode()
         }
     }
 
@@ -188,6 +194,7 @@ open class EcoConfig(
 
     override fun clearInjectedPlaceholders() {
         injections.clear()
+        injectionHash = 0 // Reset the hash
     }
 
     override fun toMap(): MutableMap<String, Any?> {
@@ -239,18 +246,6 @@ open class EcoConfig(
     }
 
     override fun hashCode(): Int {
-        /*
-        The keys are completely redundant, as they are only used to prevent
-        duplicate keys in the map. Therefore, we can ignore them and just
-        hash the actual placeholder values.
-         */
-
-        var injectionHash = 0
-
-        injections.forEachValue(5) {
-            injectionHash = injectionHash xor (it.hashCode() shl 5)
-        }
-
         // hashCode() has to compute extremely quickly, so we're using bitwise, because why not?
         // Fucking filthy to use identityHashCode here, but it should be extremely fast
         val identityHash = System.identityHashCode(this)

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/EcoConfigSection.kt

@@ -2,7 +2,6 @@ package com.willfp.eco.internal.config
 
 import com.willfp.eco.core.config.ConfigType
 import com.willfp.eco.core.placeholder.InjectablePlaceholder
-import java.util.concurrent.ConcurrentHashMap
 
 class EcoConfigSection(
     type: ConfigType,
@@ -10,7 +9,6 @@ class EcoConfigSection(
     injections: Map<String, InjectablePlaceholder> = emptyMap()
 ) : EcoConfig(type) {
     init {
-        this.init(values)
-        this.injections = ConcurrentHashMap(injections)
+        this.init(values, injections)
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/EcoLoadableConfig.kt

@@ -10,10 +10,11 @@ import java.io.IOException
 import java.io.InputStreamReader
 import java.io.OutputStream
 import java.io.Reader
+import java.nio.ByteBuffer
+import java.nio.channels.AsynchronousFileChannel
 import java.nio.file.Files
 import java.nio.file.StandardOpenOption
 
-@Suppress("UNCHECKED_CAST")
 open class EcoLoadableConfig(
     type: ConfigType,
     configName: String,
@@ -74,6 +75,20 @@ open class EcoLoadableConfig(
         }
     }
 
+    override fun saveAsync() {
+        // Save asynchronously using NIO
+        AsynchronousFileChannel.open(
+            configFile.toPath(),
+            StandardOpenOption.WRITE,
+            StandardOpenOption.CREATE
+        ).use { channel ->
+            channel.write(
+                ByteBuffer.wrap(this.toPlaintext().toByteArray()),
+                0
+            )
+        }
+    }
+
     private fun makeHeader(contents: String) {
         header.clear()
 
@@ -91,7 +106,7 @@ open class EcoLoadableConfig(
     protected fun init(reader: Reader) {
         val string = reader.readToString()
         makeHeader(string)
-        super.init(type.toMap(string))
+        super.init(type.toMap(string), emptyMap())
     }
 
     fun init(file: File) {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/EcoRepresenter.kt

@@ -1,12 +1,12 @@
 package com.willfp.eco.internal.config
 
 import com.willfp.eco.core.config.interfaces.Config
+import org.yaml.snakeyaml.DumperOptions
 import org.yaml.snakeyaml.nodes.Node
 import org.yaml.snakeyaml.representer.Represent
 import org.yaml.snakeyaml.representer.Representer
 
-@Suppress("DEPRECATION")
-class EcoRepresenter : Representer() {
+class EcoRepresenter : Representer(DumperOptions()) {
     init {
         multiRepresenters[Config::class.java] = RepresentConfig(multiRepresenters[Map::class.java]!!)
     }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/EcoUpdatableConfig.kt

@@ -50,7 +50,7 @@ open class EcoUpdatableConfig(
             val reader = BufferedReader(InputStreamReader(newIn, StandardCharsets.UTF_8))
 
             val config = EcoConfigSection(type, emptyMap())
-            config.init(type.toMap(reader.readToString()))
+            config.init(type.toMap(reader.readToString()), emptyMap())
             return config
         }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/config/handler/ReflectiveConfigHandler.kt

@@ -1,7 +1,6 @@
 package com.willfp.eco.internal.config.handler
 
 import com.willfp.eco.core.EcoPlugin
-import com.willfp.eco.core.config.updating.ConfigUpdater
 import org.reflections.Reflections
 import org.reflections.scanners.MethodAnnotationsScanner
 
@@ -14,7 +13,8 @@ class ReflectiveConfigHandler(
     )
 
     override fun callUpdate() {
-        for (method in reflections.getMethodsAnnotatedWith(ConfigUpdater::class.java)) {
+        @Suppress("DEPRECATION", "REMOVAL")
+        for (method in reflections.getMethodsAnnotatedWith(com.willfp.eco.core.config.updating.ConfigUpdater::class.java)) {
             runCatching {
                 when (method.parameterCount) {
                     0 -> method.invoke(null)

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/drops/EcoDropQueue.kt

@@ -1,5 +1,6 @@
 package com.willfp.eco.internal.drops
 
+import com.willfp.eco.core.Prerequisite
 import com.willfp.eco.core.drops.DropQueue
 import com.willfp.eco.core.events.DropQueuePushEvent
 import com.willfp.eco.core.integrations.antigrief.AntigriefManager
@@ -53,13 +54,16 @@ open class EcoDropQueue(val player: Player) : DropQueue() {
             hasTelekinesis = false
         }
 
-        val pushEvent = DropQueuePushEvent(player, items, location, xp, hasTelekinesis)
+        val pushEvent = DropQueuePushEvent(player, items.toMutableList(), location, xp, hasTelekinesis)
         Bukkit.getServer().pluginManager.callEvent(pushEvent)
 
         if (pushEvent.isCancelled) {
             return
         }
 
+        items.clear()
+        items.addAll(pushEvent.items)
+
         val world = location.world!!
         location = location.add(0.5, 0.5, 0.5)
         items.removeIf { itemStack: ItemStack -> itemStack.type == Material.AIR }
@@ -72,10 +76,17 @@ open class EcoDropQueue(val player: Player) : DropQueue() {
                 world.dropItem(location, drop!!).velocity = Vector()
             }
             if (xp > 0) {
-                val orb =
-                    world.spawnEntity(player.location.add(0.0, 0.2, 0.0), EntityType.EXPERIENCE_ORB) as ExperienceOrb
-                orb.velocity = Vector(0, 0, 0)
-                orb.experience = xp
+                if (Prerequisite.HAS_PAPER.isMet) {
+                    player.giveExp(xp, true)
+                } else {
+                    val orb =
+                        world.spawnEntity(
+                            player.location.add(0.0, 0.2, 0.0),
+                            EntityType.EXPERIENCE_ORB
+                        ) as ExperienceOrb
+                    orb.velocity = Vector(0, 0, 0)
+                    orb.experience = xp
+                }
             }
         } else {
             for (drop in items) {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserFlySpeed.kt

@@ -40,4 +40,4 @@ object EntityArgParserFlySpeed : EntityArgParser {
             }
         )
     }
-}
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/EntityArgParserName.kt

@@ -19,6 +19,7 @@ object EntityArgParserName : EntityArgParser {
 
         val formatted = StringUtils.format(name)
 
+        @Suppress("DEPRECATION")
         return EntityArgParseResult(
             { it.customName == formatted },
             {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/entities/ModernEntityArgParsers.kt

@@ -0,0 +1,8 @@
+package com.willfp.eco.internal.entities
+
+import com.willfp.eco.internal.compat.ModernCompatibilityProxy
+
+@ModernCompatibilityProxy("entities.ModernEntityArgParsersImpl")
+interface ModernEntityArgParsers {
+    fun registerAll()
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/events/EcoEventManager.kt

@@ -2,12 +2,14 @@ package com.willfp.eco.internal.events
 
 import com.willfp.eco.core.EcoPlugin
 import com.willfp.eco.core.events.EventManager
+import com.willfp.eco.core.map.listMap
 import com.willfp.eco.core.packet.PacketEvent
 import com.willfp.eco.core.packet.PacketListener
 import com.willfp.eco.core.packet.PacketPriority
 import org.bukkit.Bukkit
 import org.bukkit.event.HandlerList
 import org.bukkit.event.Listener
+import java.lang.Exception
 
 
 private class RegisteredPacketListener(
@@ -15,20 +17,48 @@ private class RegisteredPacketListener(
     val listener: PacketListener
 )
 
-private val listeners = mutableMapOf<PacketPriority, MutableList<RegisteredPacketListener>>()
+private val listeners = listMap<PacketPriority, RegisteredPacketListener>()
 
 fun PacketEvent.handleSend() {
     for (priority in PacketPriority.values()) {
-        for (listener in listeners[priority] ?: continue) {
-            listener.listener.onSend(this)
+        for (listener in listeners[priority]) {
+            try {
+                listener.listener.onSend(this)
+            } catch (e: Throwable) {
+                listener.plugin.logger.warning(
+                    "Exception in packet listener ${listener.listener.javaClass.name}" +
+                            " for packet ${packet.handle.javaClass.name}!"
+                )
+                e.printStackTrace()
+            } catch (e: LinkageError) {
+                listener.plugin.logger.warning(
+                    "Error in packet listener ${listener.listener.javaClass.name}" +
+                            " for packet ${packet.handle.javaClass.name}!"
+                )
+                e.printStackTrace()
+            }
         }
     }
 }
 
 fun PacketEvent.handleReceive() {
     for (priority in PacketPriority.values()) {
-        for (listener in listeners[priority] ?: continue) {
-            listener.listener.onReceive(this)
+        for (listener in listeners[priority]) {
+            try {
+                listener.listener.onReceive(this)
+            } catch (e: Exception) {
+                listener.plugin.logger.warning(
+                    "Exception in packet listener ${listener.listener.javaClass.name}" +
+                            " for packet ${packet.handle.javaClass.name}!"
+                )
+                e.printStackTrace()
+            } catch (e: LinkageError) {
+                listener.plugin.logger.warning(
+                    "Error in packet listener ${listener.listener.javaClass.name}" +
+                            " for packet ${packet.handle.javaClass.name}!"
+                )
+                e.printStackTrace()
+            }
         }
     }
 }
@@ -50,11 +80,9 @@ class EcoEventManager(private val plugin: EcoPlugin) : EventManager {
     }
 
     override fun registerPacketListener(listener: PacketListener) {
-        listeners.getOrPut(listener.priority) { mutableListOf() }.add(
-            RegisteredPacketListener(
-                plugin,
-                listener
-            )
+        listeners[listener.priority] += RegisteredPacketListener(
+            plugin,
+            listener
         )
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/extensions/EcoExtensionLoader.kt

@@ -42,6 +42,7 @@ class EcoExtensionLoader(
         }
     }
 
+    @Suppress("DEPRECATION")
     @Throws(MalformedExtensionException::class)
     private fun loadExtension(extensionJar: File) {
         val url = extensionJar.toURI().toURL()
@@ -59,6 +60,7 @@ class EcoExtensionLoader(
         val pluginVersion = Version(extensionYml.getStringOrNull("plugin-version") ?: "0.0.0")
         val pluginName = extensionYml.getStringOrNull("plugin")
 
+        @Suppress("DEPRECATION")
         if (pluginName != null && !pluginName.equals(this.plugin.description.name, ignoreCase = true)) {
             throw ExtensionLoadException("${extensionJar.name} is only compatible with $pluginName!")
         }
@@ -82,6 +84,7 @@ class EcoExtensionLoader(
             author = "Unnamed Author"
         }
 
+        @Suppress("DEPRECATION")
         if (Version(this.plugin.description.version) < pluginVersion) {
             throw ExtensionLoadException("Plugin version is too low for ${extensionJar.name}!")
         }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/factory/EcoNamespacedKeyFactory.kt

@@ -7,6 +7,6 @@ import org.bukkit.NamespacedKey
 
 class EcoNamespacedKeyFactory(private val plugin: EcoPlugin) : NamespacedKeyFactory {
     override fun create(key: String): NamespacedKey {
-        return NamespacedKeyUtils.create(plugin.name, key)
+        return NamespacedKeyUtils.create(plugin.id, key)
     }
-}
+}

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/fast/InternalNamespacedKeyFactory.kt

@@ -25,7 +25,6 @@ class FastInternalNamespacedKeyFactory : InternalNamespacedKeyFactory {
 
 class SafeInternalNamespacedKeyFactory : InternalNamespacedKeyFactory {
     override fun create(namespace: String, key: String): NamespacedKey {
-        @Suppress("DEPRECATION")
         return NamespacedKey(namespace, key)
     }
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/gui/menu/EcoMenu.kt

@@ -43,6 +43,7 @@ class EcoMenu(
         getPossiblyReactiveSlot(row, column, player)
 
     override fun open(player: Player): Inventory {
+        @Suppress("DEPRECATION")
         val inventory = if (columns == 9) {
             Bukkit.createInventory(null, rows * columns, title)
         } else {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/gui/menu/RenderedInventory.kt

@@ -1,7 +1,9 @@
 package com.willfp.eco.internal.gui.menu
 
+import com.willfp.eco.core.Eco
+import com.willfp.eco.core.Prerequisite
 import com.willfp.eco.core.gui.menu.events.CaptiveItemChangeEvent
-import com.willfp.eco.core.items.isEmpty
+import com.willfp.eco.core.items.isEcoEmpty
 import com.willfp.eco.core.recipe.parts.EmptyTestableItem
 import com.willfp.eco.util.MenuUtils
 import com.willfp.eco.util.openMenu
@@ -20,9 +22,23 @@ fun Player.forceRenderedInventory(menu: RenderedInventory) {
     trackedForceRendered[this.uniqueId] = menu
 }
 
+// Workaround because 1.21 has OpenInventory as an interface instead of an abstract class like in previous versions
+interface TopInventoryProxy {
+    fun getTopInventory(player: Player): Inventory
+}
+
+private val Player.topInventory: Inventory
+    get() {
+        return if (!Prerequisite.HAS_1_21.isMet) {
+            Eco.get().ecoPlugin.getProxy(TopInventoryProxy::class.java).getTopInventory(this)
+        } else {
+            this.openInventory.topInventory
+        }
+    }
+
 val Player.renderedInventory: RenderedInventory?
     get() = trackedForceRendered[this.uniqueId]
-        ?: this.openInventory.topInventory.asRenderedInventory()
+        ?: this.topInventory.asRenderedInventory()
 
 class RenderedInventory(
     val menu: EcoMenu,
@@ -55,7 +71,7 @@ class RenderedInventory(
                     val actualItem = inventory.getItem(bukkit) ?: continue
 
                     if (slot.isCaptiveFromEmpty) {
-                        if (!actualItem.isEmpty) {
+                        if (!actualItem.isEcoEmpty) {
                             newCaptive[position] = actualItem
                         }
                     } else {

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/gui/slot/EcoSlot.kt

@@ -34,4 +34,6 @@ open class EcoSlot(
     }
 
     override fun getActionableSlot(player: Player, menu: Menu): EcoSlot = this
+
+    override fun shouldRenderOnClick(clickType: ClickType) = !handlers[clickType].isNullOrEmpty()
 }

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/gui/slot/EcoSlotBuilder.kt

@@ -6,6 +6,7 @@ import com.willfp.eco.core.gui.slot.functional.CaptiveFilter
 import com.willfp.eco.core.gui.slot.functional.SlotHandler
 import com.willfp.eco.core.gui.slot.functional.SlotProvider
 import com.willfp.eco.core.gui.slot.functional.SlotUpdater
+import com.willfp.eco.core.map.listMap
 import org.bukkit.entity.Player
 import org.bukkit.event.inventory.ClickType
 import java.util.function.Predicate
@@ -15,14 +16,14 @@ class EcoSlotBuilder(private val provider: SlotProvider) : SlotBuilder {
     private var captiveFromEmpty = false
     private var updater: SlotUpdater = SlotUpdater { player, menu, _ -> provider.provide(player, menu) }
 
-    private val handlers = mutableMapOf<ClickType, MutableList<SlotHandler>>()
+    private val handlers = listMap<ClickType, SlotHandler>()
 
     private var captiveFilter =
         CaptiveFilter { _, _, _ -> true }
     private var notCaptiveFor: (Player) -> Boolean = { _ -> false}
 
     override fun onClick(type: ClickType, action: SlotHandler): SlotBuilder {
-        handlers.computeIfAbsent(type) { mutableListOf() } += action
+        handlers[type] += action
         return this
     }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/integrations/PAPIExpansion.kt

@@ -6,6 +6,7 @@ import com.willfp.eco.core.placeholder.context.placeholderContext
 import me.clip.placeholderapi.expansion.PlaceholderExpansion
 import org.bukkit.entity.Player
 
+@Suppress("DEPRECATION")
 class PAPIExpansion(private val plugin: EcoPlugin) : PlaceholderExpansion() {
     init {
         register()
@@ -20,14 +21,17 @@ class PAPIExpansion(private val plugin: EcoPlugin) : PlaceholderExpansion() {
     }
 
     override fun getAuthor(): String {
+        @Suppress("DEPRECATION")
         return java.lang.String.join(", ", plugin.description.authors)
     }
 
     override fun getIdentifier(): String {
+        @Suppress("DEPRECATION")
         return plugin.description.name.lowercase()
     }
 
     override fun getVersion(): String {
+        @Suppress("DEPRECATION")
         return plugin.description.version
     }
 

eco-core/core-backend/src/main/kotlin/com/willfp/eco/internal/items/ArgParserColor.kt

@@ -49,4 +49,4 @@ object ArgParserColor : LookupArgParser {
 
         return "color:#${Integer.toHexString(meta.color.asRGB())}"
     }
-}
+}