[ENHANCEMENT] Add Script Events for losing/gaining focus (#3721)

* add events for focus gain/lost

* add callbacks

* move the events to a new interface

* Ok NOW it works

* the event can now longer be canceled

source/funkin/modding/IScriptedClass.hx

@@ -37,6 +37,9 @@ interface IStateChangingScriptedClass extends IScriptedClass
   public function onSubStateOpenEnd(event:SubStateScriptEvent):Void;
   public function onSubStateCloseBegin(event:SubStateScriptEvent):Void;
   public function onSubStateCloseEnd(event:SubStateScriptEvent):Void;
+
+  public function onFocusLost(event:FocusScriptEvent):Void;
+  public function onFocusGained(event:FocusScriptEvent):Void;
 }
 
 /**

source/funkin/modding/events/ScriptEvent.hx

@@ -436,6 +436,22 @@ class StateChangeScriptEvent extends ScriptEvent
   }
 }
 
+/**
+ * An event that is fired when the game loses or gains focus.
+ */
+class FocusScriptEvent extends ScriptEvent
+{
+  public function new(type:ScriptEventType):Void
+  {
+    super(type, false);
+  }
+
+  public override function toString():String
+  {
+    return 'FocusScriptEvent(type=' + type + ')';
+  }
+}
+
 /**
  * An event that is fired when moving out of or into an FlxSubState.
  */

source/funkin/modding/events/ScriptEventDispatcher.hx

@@ -177,6 +177,12 @@ class ScriptEventDispatcher
         case SUBSTATE_CLOSE_END:
           t.onSubStateCloseEnd(cast event);
           return;
+        case FOCUS_LOST:
+          t.onFocusLost(cast event);
+          return;
+        case FOCUS_GAINED:
+          t.onFocusGained(cast event);
+          return;
         default: // Continue;
       }
     }

source/funkin/modding/events/ScriptEventType.hx

@@ -223,6 +223,20 @@ enum abstract ScriptEventType(String) from String to String
    */
   var SUBSTATE_CLOSE_END = 'SUBSTATE_CLOSE_END';
 
+  /**
+   * Called when the game regains focus.
+   *
+   * This event is not cancelable.
+   */
+  var FOCUS_GAINED = 'FOCUS_GAINED';
+
+  /**
+   * Called when the game loses focus.
+   *
+   * This event is not cancelable.
+   */
+  var FOCUS_LOST = 'FOCUS_LOST';
+
   /**
    * Called when the game starts a conversation.
    *

source/funkin/modding/module/Module.hx

@@ -109,6 +109,10 @@ class Module implements IPlayStateScriptedClass implements IStateChangingScripte
 
   public function onStateChangeEnd(event:StateChangeScriptEvent) {}
 
+  public function onFocusGained(event:FocusScriptEvent) {}
+
+  public function onFocusLost(event:FocusScriptEvent) {}
+
   public function onSubStateOpenBegin(event:SubStateScriptEvent) {}
 
   public function onSubStateOpenEnd(event:SubStateScriptEvent) {}

source/funkin/ui/MusicBeatState.hx

@@ -87,6 +87,20 @@ class MusicBeatState extends FlxTransitionableState implements IEventHandler
     dispatchEvent(new UpdateScriptEvent(elapsed));
   }
 
+  override function onFocus():Void
+  {
+    super.onFocus();
+
+    dispatchEvent(new FocusScriptEvent(FOCUS_GAINED));
+  }
+
+  override function onFocusLost():Void
+  {
+    super.onFocusLost();
+
+    dispatchEvent(new FocusScriptEvent(FOCUS_LOST));
+  }
+
   function createWatermarkText()
   {
     // Both have an xPos of 0, but a width equal to the full screen.

source/funkin/ui/MusicBeatSubState.hx

@@ -89,6 +89,20 @@ class MusicBeatSubState extends FlxSubState implements IEventHandler
     dispatchEvent(new UpdateScriptEvent(elapsed));
   }
 
+  override function onFocus():Void
+  {
+    super.onFocus();
+
+    dispatchEvent(new FocusScriptEvent(FOCUS_GAINED));
+  }
+
+  override function onFocusLost():Void
+  {
+    super.onFocusLost();
+
+    dispatchEvent(new FocusScriptEvent(FOCUS_LOST));
+  }
+
   public function initConsoleHelpers():Void {}
 
   function reloadAssets()