Finally added paper plugin manager support

.gitignore

@@ -1,8 +1,8 @@
-/.gradle/
+.gradle/
 /.idea/
 /.vscode/
 /bin/
-/build/
+build/
 /out/
 *.iml
 /run

PaperSupport/build.gradle

@@ -0,0 +1,30 @@
+plugins {
+    id "java"
+    id "maven-publish"
+    id "io.papermc.paperweight.userdev" version "1.5.5"
+}
+
+java.toolchain.languageVersion = JavaLanguageVersion.of(17)
+compileJava.options.encoding = "UTF-8"
+
+archivesBaseName = "PaperSupport"
+group = project.maven_group
+version = project.maven_version
+
+repositories {
+    mavenCentral()
+    mavenLocal()
+}
+
+dependencies {
+    paperweight.paperDevBundle("1.20-R0.1-SNAPSHOT")
+}
+
+java {
+    withSourcesJar()
+    withJavadocJar()
+}
+
+javadoc {
+    failOnError = false
+}

PaperSupport/src/main/java/net/lenni0451/spm/storage/SingularRuntimePluginProviderStorage.java

@@ -0,0 +1,72 @@
+package net.lenni0451.spm.storage;
+
+import com.destroystokyo.paper.util.SneakyThrow;
+import com.google.common.collect.ImmutableList;
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.LaunchEntryPointHandler;
+import io.papermc.paper.plugin.provider.PluginProvider;
+import io.papermc.paper.plugin.provider.type.paper.PaperPluginParent;
+import io.papermc.paper.plugin.storage.ServerPluginProviderStorage;
+import org.bukkit.plugin.InvalidPluginException;
+import org.bukkit.plugin.PluginDescriptionFile;
+import org.bukkit.plugin.java.JavaPlugin;
+
+import java.lang.reflect.Field;
+import java.util.Optional;
+
+public class SingularRuntimePluginProviderStorage extends ServerPluginProviderStorage {
+
+    private PluginProvider<JavaPlugin> lastProvider;
+    private JavaPlugin singleLoaded;
+
+    @Override
+    public void register(PluginProvider<JavaPlugin> provider) {
+        super.register(provider);
+        if (this.lastProvider != null) {
+            SneakyThrow.sneaky(new InvalidPluginException("Plugin registered two JavaPlugins"));
+        }
+        if (provider instanceof PaperPluginParent.PaperServerPluginProvider) {
+            throw new IllegalStateException("Cannot register paper plugins during runtime!");
+        }
+        this.lastProvider = provider;
+        // Register the provider into the server entrypoint, this allows it to show in /plugins correctly.
+        // Generally it might be better in the future to make a separate storage, as putting it into the entrypoint handlers doesn't make much sense.
+        LaunchEntryPointHandler.INSTANCE.register(Entrypoint.PLUGIN, provider);
+    }
+
+    @Override
+    public void enter() {
+        PluginProvider<JavaPlugin> provider = this.lastProvider;
+        if (provider == null) {
+            return;
+        }
+        // Manually validate dependencies, LEGACY BEHAVIOR.
+        // Normally it is logged, but manually adding one plugin will cause it to actually throw exceptions.
+        PluginDescriptionFile descriptionFile = (PluginDescriptionFile) provider.getMeta();
+        try {
+            Field depend = descriptionFile.getClass().getDeclaredField("depend");
+            depend.setAccessible(true);
+            depend.set(descriptionFile, ImmutableList.of());
+        } catch (IllegalAccessException | NoSuchFieldException e) {
+            SneakyThrow.sneaky(e);
+        }
+        // Go through normal plugin loading logic
+        super.enter();
+    }
+
+    @Override
+    public void processProvided(PluginProvider<JavaPlugin> provider, JavaPlugin provided) {
+        super.processProvided(provider, provided);
+        this.singleLoaded = provided;
+    }
+
+    @Override
+    public boolean throwOnCycle() {
+        return false;
+    }
+
+    public Optional<JavaPlugin> getSingleLoaded() {
+        return Optional.ofNullable(this.singleLoaded);
+    }
+
+}

PaperSupport/src/main/java/net/lenni0451/spm/utils/PaperSupport.java

@@ -0,0 +1,36 @@
+package net.lenni0451.spm.utils;
+
+import io.papermc.paper.plugin.entrypoint.Entrypoint;
+import io.papermc.paper.plugin.entrypoint.EntrypointHandler;
+import io.papermc.paper.plugin.provider.type.PluginFileType;
+import io.papermc.paper.plugin.storage.ProviderStorage;
+import net.lenni0451.spm.storage.SingularRuntimePluginProviderStorage;
+import org.bukkit.plugin.Plugin;
+
+import java.io.File;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.util.jar.JarFile;
+
+public class PaperSupport {
+
+    public static Plugin loadPlugin(final File targetFile) throws Exception {
+        Class<?> RuntimePluginEntrypointHandler = Class.forName("io.papermc.paper.plugin.manager.RuntimePluginEntrypointHandler");
+
+        Constructor<?> constructor = RuntimePluginEntrypointHandler.getDeclaredConstructor(ProviderStorage.class);
+        constructor.setAccessible(true);
+        SingularRuntimePluginProviderStorage storage = new SingularRuntimePluginProviderStorage();
+        EntrypointHandler handler = (EntrypointHandler) constructor.newInstance(storage);
+
+        JarFile file = new JarFile(targetFile);
+        PluginFileType<?, ?> type = PluginFileType.guessType(file);
+        type.register(handler, file, targetFile.toPath());
+
+        handler.enter(Entrypoint.PLUGIN);
+        Method getProviderStorage = RuntimePluginEntrypointHandler.getDeclaredMethod("getPluginProviderStorage");
+        getProviderStorage.setAccessible(true);
+        SingularRuntimePluginProviderStorage providerStorage = (SingularRuntimePluginProviderStorage) getProviderStorage.invoke(handler);
+        return providerStorage.getSingleLoaded().get();
+    }
+
+}

build.gradle

@@ -27,6 +27,13 @@ dependencies {
     compileOnly "spigot:1.8.8-R0.1-SNAPSHOT"
 }
 
+jar {
+    from {
+        duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+        zipTree(project(":PaperSupport").jar.archiveFile)
+    }
+}
+
 java {
     withSourcesJar()
     withJavadocJar()

settings.gradle

@@ -6,3 +6,5 @@ pluginManagement {
 }
 
 rootProject.name = 'SpigotPluginManager'
+
+include(":PaperSupport")

src/main/java/net/lenni0451/spm/utils/PluginUtils.java

@@ -246,7 +246,13 @@ public Plugin loadPlugin(final String name) {
         this.updatePlugin(targetFile.get());
 
         try {
-            targetPlugin = this.getPluginManager().loadPlugin(targetFile.get());
+            try {
+                Class.forName("io.papermc.paper.plugin.entrypoint.EntrypointHandler");
+                Class<?> PaperSupport = Class.forName("net.lenni0451.spm.utils.PaperSupport");
+                targetPlugin = (Plugin) PaperSupport.getDeclaredMethod("loadPlugin", File.class).invoke(null, targetFile.get());
+            } catch (ClassNotFoundException e) {
+                targetPlugin = this.getPluginManager().loadPlugin(targetFile.get());
+            }
         } catch (UnknownDependencyException e) {
 //            throw new IllegalStateException("Missing Dependency");
             throw new IllegalStateException(I18n.t("pm.pluginutils.loadPlugin.missingDependency"));
@@ -256,6 +262,10 @@ public Plugin loadPlugin(final String name) {
         } catch (InvalidDescriptionException e) {
 //            throw new IllegalStateException("Invalid plugin description");
             throw new IllegalStateException(I18n.t("pm.pluginutils.loadPlugin.invalidPluginDescription"));
+        } catch (Exception e) {
+            //Only for paper support
+//            throw new IllegalStateException("Invalid plugin file");
+            throw new IllegalStateException(I18n.t("pm.pluginutils.loadPlugin.invalidPluginFile"));
         }
 
         targetPlugin.onLoad();