Funkin/source/flixel/addons/transition/FlxTransitionableSubState.hx

package flixel.addons.transition;

import flixel.FlxSubState;
import flixel.addons.transition.FlxTransitionableState;

/**
 * A `FlxSubState` which can perform visual transitions
 *
 * Usage:
 *
 * First, extend `FlxTransitionableSubState` as ie, `FooState`.
 *
 * Method 1:
 *
 * ```haxe
 * var in:TransitionData = new TransitionData(...); // add your data where "..." is
 * var out:TransitionData = new TransitionData(...);
 *
 * FlxG.switchState(() -> new FooState(in,out));
 * ```
 *
 * Method 2:
 *
 * ```haxe
 * FlxTransitionableSubState.defaultTransIn = new TransitionData(...);
 * FlxTransitionableSubState.defaultTransOut = new TransitionData(...);
 *
 * FlxG.switchState(() -> new FooState());
 * ```
 */
class FlxTransitionableSubState extends FlxSubState
{
  // global default transitions for ALL states, used if transIn/transOut are null
  public static var defaultTransIn(get, set):TransitionData;

  static function get_defaultTransIn():TransitionData
  {
    return FlxTransitionableState.defaultTransIn;
  }

  static function set_defaultTransIn(value:TransitionData):TransitionData
  {
    return FlxTransitionableState.defaultTransIn = value;
  }

  public static var defaultTransOut(get, set):TransitionData;

  static function get_defaultTransOut():TransitionData
  {
    return FlxTransitionableState.defaultTransOut;
  }

  static function set_defaultTransOut(value:TransitionData):TransitionData
  {
    return FlxTransitionableState.defaultTransOut = value;
  }

  public static var skipNextTransIn(get, set):Bool;

  static function get_skipNextTransIn():Bool
  {
    return FlxTransitionableState.skipNextTransIn;
  }

  static function set_skipNextTransIn(value:Bool):Bool
  {
    return FlxTransitionableState.skipNextTransIn = value;
  }

  public static var skipNextTransOut(get, set):Bool;

  static function get_skipNextTransOut():Bool
  {
    return FlxTransitionableState.skipNextTransOut;
  }

  static function set_skipNextTransOut(value:Bool):Bool
  {
    return FlxTransitionableState.skipNextTransOut = value;
  }

  // beginning & ending transitions for THIS state:
  public var transIn:TransitionData;
  public var transOut:TransitionData;

  public var hasTransIn(get, never):Bool;
  public var hasTransOut(get, never):Bool;

  /**
   * Create a state with the ability to do visual transitions
   * @param	TransIn		Plays when the state begins
   * @param	TransOut	Plays when the state ends
   */
  public function new(?TransIn:TransitionData, ?TransOut:TransitionData)
  {
    transIn = TransIn;
    transOut = TransOut;

    if (transIn == null && defaultTransIn != null)
    {
      transIn = defaultTransIn;
    }
    if (transOut == null && defaultTransOut != null)
    {
      transOut = defaultTransOut;
    }
    super();
  }

  override function destroy():Void
  {
    super.destroy();
    transIn = null;
    transOut = null;
    _onExit = null;
  }

  override function create():Void
  {
    super.create();
    transitionIn();
  }

  override function startOutro(onOutroComplete:() -> Void)
  {
    if (!hasTransOut) onOutroComplete();
    else if (!_exiting)
    {
      // play the exit transition, and when it's done call FlxG.switchState
      _exiting = true;
      transitionOut(onOutroComplete);

      if (skipNextTransOut)
      {
        skipNextTransOut = false;
        finishTransOut();
      }
    }
  }

  /**
   * Starts the in-transition. Can be called manually at any time.
   */
  public function transitionIn():Void
  {
    if (transIn != null && transIn.type != NONE)
    {
      if (skipNextTransIn)
      {
        skipNextTransIn = false;
        if (finishTransIn != null)
        {
          finishTransIn();
        }
        return;
      }

      var _trans = createTransition(transIn);

      _trans.setStatus(FULL);
      openSubState(_trans);

      _trans.finishCallback = finishTransIn;
      _trans.start(OUT);
    }
  }

  /**
   * Starts the out-transition. Can be called manually at any time.
   */
  public function transitionOut(?OnExit:Void->Void):Void
  {
    _onExit = OnExit;
    if (hasTransOut)
    {
      var _trans = createTransition(transOut);

      _trans.setStatus(EMPTY);
      openSubState(_trans);

      _trans.finishCallback = finishTransOut;
      _trans.start(IN);
    }
    else
    {
      _onExit();
    }
  }

  var transOutFinished:Bool = false;

  var _exiting:Bool = false;
  var _onExit:Void->Void;

  function get_hasTransIn():Bool
  {
    return transIn != null && transIn.type != NONE;
  }

  function get_hasTransOut():Bool
  {
    return transOut != null && transOut.type != NONE;
  }

  function createTransition(data:TransitionData):Transition
  {
    return switch (data.type)
    {
      case TILES: new Transition(data);
      case FADE: new Transition(data);
      default: null;
    }
  }

  function finishTransIn()
  {
    closeSubState();
  }

  function finishTransOut()
  {
    transOutFinished = true;

    if (!_exiting)
    {
      closeSubState();
    }

    if (_onExit != null)
    {
      _onExit();
    }
  }
}