samples/poppopwin: upgrade to first-class sample

samples/third_party/pop-pop-win/lib/src/canvas/game_root.dart

-part of ppw_canvas;
-
-class GameRoot extends GameManager {
-  final Stage _stage;
-  final CanvasElement _canvas;
-  final GameElement _gameElement;
-  final AffineTransform _gameElementTx;
-
-  bool _frameRequested = false;
-
-  factory GameRoot(int width, int height, int bombCount,
-      CanvasElement canvasElement, TextureData textureData) {
-
-    final rootElement = new GameElement(textureData);
-    final stage = new Stage(canvasElement, rootElement);
-    new MouseManager(stage);
-
-    return new GameRoot._internal(width, height, bombCount,
-        canvasElement, stage, rootElement);
-  }
-
-  GameRoot._internal(int width, int height, int bombCount,
-      this._canvas, this._stage, GameElement gameElement) :
-      this._gameElement = gameElement,
-      _gameElementTx = gameElement.addTransform(),
-      super(width, height, bombCount) {
-
-    _gameElement.setGameManager(this);
-    _stage.invalidated.listen(_stageInvalidated);
-
-    _gameElement.newGameClick.listen((args) => newGame());
-
-    MouseManager.getMouseMoveStream(_gameElement).listen(_mouseMoveHandler);
-    MouseManager.getMouseOutStream(_stage).listen(_mouseOutHandler);
-
-    window.onResize.listen((args) => _updateCanvasSize());
-    _updateCanvasSize();
-  }
-
-  void newGame() {
-    super.newGame();
-    _gameElement.game = super.game;
-    _requestFrame();
-  }
-
-  bool get canRevealTarget => _gameElement.canRevealTarget;
-
-  bool get canFlagTarget => _gameElement.canFlagTarget;
-
-  void revealTarget() => _gameElement.revealTarget();
-
-  void toggleTargetFlag() => _gameElement.toggleTargetFlag();
-
-  Stream get targetChanged => _gameElement.targetChanged;
-
-  void onGameStateChanged(GameState newState) {
-    switch(newState) {
-      case GameState.won:
-        GameAudio.win();
-        break;
-    }
-    targetPlatform.trackAnalyticsEvent('game', newState.name, game.field.toString());
-  }
-
-  void onNewBestTime(int value) {
-    targetPlatform.trackAnalyticsEvent('game', 'record', game.field.toString(), value);
-  }
-
-  void _updateCanvasSize() {
-    final windowSize = new Size(window.innerWidth, window.innerHeight);
-
-    _canvas.width = min(windowSize.width, _gameElement.width).toInt();
-    _canvas.height = min(windowSize.height, _gameElement.height).toInt();
-
-    // now move it!
-    final delta = new Vector(windowSize.width - _canvas.width,
-        windowSize.height - _canvas.height).scale(0.5);
-
-    _canvas.style.left = "${delta.x.toInt()}px";
-
-    // add a little padding at the top (up to 20) if there's room
-    // but don't try to vertically center
-    final topDelta = min(delta.y, 20).toInt();
-    _canvas.style.top = "${topDelta}px";
-
-    _requestFrame();
-  }
-
-  void _requestFrame() {
-    if(!_frameRequested) {
-      _frameRequested = true;
-      window.requestAnimationFrame(_onFrame);
-    }
-  }
-
-  void _onFrame(double time) {
-    final boardInnerBox = _gameElement._scaledInnerBox;
-    final xScale = _stage.size.width / boardInnerBox.width;
-    final yScale = _stage.size.height / boardInnerBox.height;
-
-    final prettyScale = min(1, min(xScale, yScale));
-
-    final newDimensions = _gameElement.size * prettyScale;
-
-    final delta = new Vector(_stage.size.width - newDimensions.width,
-        min(40, _stage.size.height - newDimensions.height))
-      .scale(0.5)
-      .scale(1/prettyScale);
-
-    _gameElementTx.setToScale(prettyScale, prettyScale);
-    _gameElementTx.translate(delta.x, delta.y);
-
-    var updated = _stage.draw();
-    _frameRequested = false;
-    if(updated) {
-      _requestFrame();
-    }
-  }
-
-  void updateClock() {
-    _requestFrame();
-    super.updateClock();
-  }
-
-  void gameUpdated(args) {
-    _requestFrame();
-  }
-
-  void _stageInvalidated(args) {
-    _requestFrame();
-  }
-
-  void _mouseMoveHandler(ThingMouseEventArgs args) {
-    bool showPointer = false;
-    if(!game.gameEnded && args.thing is SquareElement) {
-      final SquareElement se = args.thing;
-      showPointer = game.canReveal(se.x, se.y);
-    } else if(args.thing is NewGameElement) {
-      showPointer = true;
-    } else if(args.thing is GameTitleElement) {
-      showPointer = true;
-    }
-    _updateCursor(showPointer);
-  }
-
-  void _mouseOutHandler(args) {
-    _updateCursor(false);
-  }
-
-  void _updateCursor(bool showFinger) {
-    _canvas.style.cursor = showFinger ? 'pointer' : 'inherit';
-  }
-}