Implement ExprPlugin (#49)

Co-authored-by: TPGamesNL <[email protected]>

Author: Pikachu920

docs/basics/utilities.md

@@ -175,3 +175,15 @@ Checks whether objects are instances of the given java types.
 Returns a reference to the class from the given java type. Returns an object of type `java.lang.Class`.
 This expression also supports primitive types, which doesn't require an import.
 
+## Plugin instance
+
+{% code-tabs %}
+{% code-tabs-item title="Syntax" %}
+```text
+[(an|the)] instance of [the] plugin %javatype/string%
+```
+{% endcode-tabs-item %}
+{% endcode-tabs %}
+
+Returns the instance of the given plugin (either the name as a string, or the plugin class).
+

src/main/java/com/btk5h/skriptmirror/skript/ExprPlugin.java

@@ -0,0 +1,74 @@
+package com.btk5h.skriptmirror.skript;
+
+import ch.njol.skript.Skript;
+import ch.njol.skript.expressions.base.SimplePropertyExpression;
+import ch.njol.skript.lang.Expression;
+import ch.njol.skript.lang.ExpressionType;
+import ch.njol.skript.lang.SkriptParser;
+import ch.njol.util.Kleenean;
+import com.btk5h.skriptmirror.JavaType;
+import com.btk5h.skriptmirror.ObjectWrapper;
+import com.btk5h.skriptmirror.skript.custom.CustomImport;
+import org.bukkit.Bukkit;
+import org.bukkit.plugin.Plugin;
+import org.bukkit.plugin.java.JavaPlugin;
+import org.eclipse.jdt.annotation.NonNull;
+
+public class ExprPlugin extends SimplePropertyExpression<Object, ObjectWrapper> {
+
+  static {
+    Skript.registerExpression(ExprPlugin.class, ObjectWrapper.class, ExpressionType.PROPERTY, "[(an|the)] instance of [the] plugin %javatype/string%");
+  }
+
+  @Override
+  public boolean init(Expression<?>[] exprs, int matchedPattern, Kleenean isDelayed, SkriptParser.ParseResult parseResult) {
+    super.init(exprs, matchedPattern, isDelayed, parseResult);
+
+    if (exprs[0] instanceof CustomImport.ImportHandler) {
+      JavaType javaType = ((CustomImport.ImportHandler) exprs[0]).getJavaType();
+      Class<?> clazz = javaType.getJavaClass();
+
+      if (!JavaPlugin.class.isAssignableFrom(clazz) || JavaPlugin.class.equals(clazz)) {
+        Skript.error("The class " + clazz.getSimpleName() + " is not a plugin class");
+        return false;
+      }
+    }
+
+    return true;
+  }
+
+  @Override
+  public ObjectWrapper convert(Object plugin) {
+    if (plugin instanceof String) {
+      String pluginName = (String) plugin;
+      for (Plugin pluginInstance : Bukkit.getPluginManager().getPlugins()) {
+        if (pluginInstance.getName().equalsIgnoreCase(pluginName)) {
+          return ObjectWrapper.create(pluginInstance);
+        }
+      }
+
+      return null;
+    } else {
+      Class<?> clazz = ((JavaType) plugin).getJavaClass();
+
+      if (!JavaPlugin.class.isAssignableFrom(clazz) || JavaPlugin.class.equals(clazz)) {
+        return null;
+      }
+
+      return ObjectWrapper.create(JavaPlugin.getPlugin(clazz.asSubclass(JavaPlugin.class)));
+    }
+  }
+
+  @Override
+  @NonNull
+  public Class<? extends ObjectWrapper> getReturnType() {
+    return ObjectWrapper.class;
+  }
+
+  @Override
+  @NonNull
+  protected String getPropertyName() {
+    return "plugin instance";
+  }
+
+}