tools/dom/templates/html/impl/impl_Window.darttemplate

// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

part of $LIBRARYNAME;

$if DART2JS
$(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS native "Window,DOMWindow" {
$else
$(ANNOTATIONS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
$endif

  /**
   * Executes a [callback] after the immediate execution stack has completed.
   *
   * This differs from using Timer.run(callback)
   * because Timer will run in about 4-15 milliseconds, depending on browser,
   * depending on load. [setImmediate], in contrast, makes browser-specific
   * changes in behavior to attempt to run immediately after the current
   * frame unwinds, causing the future to complete after all processing has
   * completed for the current event, but before any subsequent events.
   */
  void setImmediate(TimeoutHandler callback) {
    _addMicrotaskCallback(callback);
  }
  /**
   * Lookup a port by its [name].  Return null if no port is
   * registered under [name].
   */
  SendPortSync lookupPort(String name) {
    var portStr = document.documentElement.attributes['dart-port:$name'];
    if (portStr == null) {
      return null;
    }
    var port = json.parse(portStr);
    return _deserialize(port);
  }

  /**
   * Register a [port] on this window under the given [name].  This
   * port may be retrieved by any isolate (or JavaScript script)
   * running in this window.
   */
  void registerPort(String name, var port) {
    var serialized = _serialize(port);
    document.documentElement.attributes['dart-port:$name'] =
        json.stringify(serialized);
  }

  /**
   * Returns a Future that completes just before the window is about to 
   * repaint so the user can draw an animation frame.
   *
   * If you need to later cancel this animation, use [requestAnimationFrame]
   * instead.
   *
   * The [Future] completes to a timestamp that represents a floating
   * point value of the number of milliseconds that have elapsed since the page 
   * started to load (which is also the timestamp at this call to 
   * animationFrame).
   *
   * Note: The code that runs when the future completes should call
   * [animationFrame] again for the animation to continue.
   */
  Future<num> get animationFrame {
    var completer = new Completer<num>();
    requestAnimationFrame((time) {
      completer.complete(time);
    });
    return completer.future;
  }

$if DART2JS
  Document get document => JS('Document', '#.document', this);

  WindowBase _open2(url, name) => JS('Window', '#.open(#,#)', this, url, name);

  WindowBase _open3(url, name, options) =>
      JS('Window', '#.open(#,#,#)', this, url, name, options);

  WindowBase open(String url, String name, [String options]) {
    if (options == null) {
      return _DOMWindowCrossFrame._createSafe(_open2(url, name));
    } else {
      return _DOMWindowCrossFrame._createSafe(_open3(url, name, options));
    }
  }

  // API level getter and setter for Location.
  // TODO: The cross domain safe wrapper can be inserted here or folded into
  // _LocationWrapper.
  Location get location {
    // Firefox work-around for Location.  The Firefox location object cannot be
    // made to behave like a Dart object so must be wrapped.
    var result = _location;
    if (_isDartLocation(result)) return result;  // e.g. on Chrome.
    if (null == _location_wrapper) {
      _location_wrapper = new _LocationWrapper(result);
    }
    return _location_wrapper;
  }

  // TODO: consider forcing users to do: window.location.assign('string').
  /**
   * Sets the window's location, which causes the browser to navigate to the new
   * location. [value] may be a Location object or a string.
   */
  void set location(value) {
    if (value is _LocationWrapper) {
      _location = value._ptr;
    } else {
      _location = value;
    }
  }

  _LocationWrapper _location_wrapper;  // Cached wrapped Location object.

  // Native getter and setter to access raw Location object.
  dynamic get _location => JS('Location|=Object', '#.location', this);
  void set _location(value) {
    JS('void', '#.location = #', this, value);
  }
  // Prevent compiled from thinking 'location' property is available for a Dart
  // member.
  @JSName('location')
  _protect_location() native;

  static _isDartLocation(thing) {
    // On Firefox the code that implements 'is Location' fails to find the patch
    // stub on Object.prototype and throws an exception.
    try {
      return thing is Location;
    } catch (e) {
      return false;
    }
  }

  /**
   * Called to draw an animation frame and then request the window to repaint
   * after [callback] has finished (creating the animation).
   *
   * Use this method only if you need to later call [cancelAnimationFrame]. If
   * not, the preferred Dart idiom is to set animation frames by calling
   * [animationFrame], which returns a Future.
   *
   * Returns a non-zero valued integer to represent the request id for this
   * request. This value only needs to be saved if you intend to call
   * [cancelAnimationFrame] so you can specify the particular animation to
   * cancel.
   *
   * Note: The supplied [callback] needs to call [requestAnimationFrame] again
   * for the animation to continue.
   */
  @DomName('DOMWindow.requestAnimationFrame')
  int requestAnimationFrame(RequestAnimationFrameCallback callback) {
    _ensureRequestAnimationFrame();
    return _requestAnimationFrame(callback);
  }

  void cancelAnimationFrame(int id) {
    _ensureRequestAnimationFrame();
    _cancelAnimationFrame(id);
  }

  @JSName('requestAnimationFrame')
  int _requestAnimationFrame(RequestAnimationFrameCallback callback) native;

  @JSName('cancelAnimationFrame')
  void _cancelAnimationFrame(int id) native;

  _ensureRequestAnimationFrame() {
    if (JS('bool',
           '!!(#.requestAnimationFrame && #.cancelAnimationFrame)', this, this))
      return;

    JS('void',
       r"""
  (function($this) {
   var vendors = ['ms', 'moz', 'webkit', 'o'];
   for (var i = 0; i < vendors.length && !$this.requestAnimationFrame; ++i) {
     $this.requestAnimationFrame = $this[vendors[i] + 'RequestAnimationFrame'];
     $this.cancelAnimationFrame =
         $this[vendors[i]+'CancelAnimationFrame'] ||
         $this[vendors[i]+'CancelRequestAnimationFrame'];
   }
   if ($this.requestAnimationFrame && $this.cancelAnimationFrame) return;
   $this.requestAnimationFrame = function(callback) {
      return window.setTimeout(function() {
        callback(Date.now());
      }, 16 /* 16ms ~= 60fps */);
   };
   $this.cancelAnimationFrame = function(id) { clearTimeout(id); }
  })(#)""",
       this);
  }

  /**
   * Gets an instance of the Indexed DB factory to being using Indexed DB.
   *
   * Use [IdbFactory.supported] to check if Indexed DB is supported on the
   * current platform.
   */
  @SupportedBrowser(SupportedBrowser.CHROME, '23.0')
  @SupportedBrowser(SupportedBrowser.FIREFOX, '15.0')
  @SupportedBrowser(SupportedBrowser.IE, '10.0')
  @Experimental
  IdbFactory get indexedDB =>
      JS('IdbFactory|Null',  // If not supported, returns `null`.
         '#.indexedDB || #.webkitIndexedDB || #.mozIndexedDB',
         this, this, this);

  @DomName('Window.console')
  Console get console => Console._safeConsole;

  /// Checks if _setImmediate is supported.
  static bool get _supportsSetImmediate =>
      JS('bool', '!!(window.setImmediate)');

  // Set immediate implementation for IE
  void _setImmediate(void callback()) {
    JS('void', '#.setImmediate(#)', this, convertDartClosureToJS(callback, 0));
  }
$else
  /// Checks if _setImmediate is supported.
  static bool get _supportsSetImmediate => false;

  /// Dartium stub for IE's setImmediate.
  void _setImmediate(void callback()) {
    throw new UnsupportedError('setImmediate is not supported');
  }
$endif

  /**
   * Access a sandboxed file system of the specified `size`. If `persistent` is
   * true, the application will request permission from the user to create
   * lasting storage. This storage cannot be freed without the user's
   * permission. Returns a [Future] whose value stores a reference to the
   * sandboxed file system for use. Because the file system is sandboxed,
   * applications cannot access file systems created in other web pages.
   */
  Future<FileSystem> requestFileSystem(int size, {bool persistent: false}) {
    return _requestFileSystem(persistent? 1 : 0, size);
  }

  @DomName('DOMWindow.convertPointFromNodeToPage')
  @SupportedBrowser(SupportedBrowser.CHROME)
  @SupportedBrowser(SupportedBrowser.SAFARI)
  @Experimental
  Point convertPointFromNodeToPage(Node node, Point point) {
    var result = _convertPointFromNodeToPage(node,
        new _DomPoint(point.x, point.y));
    return new Point(result.x, result.y);
  }

  @DomName('DOMWindow.convertPointFromPageToNode')
  @SupportedBrowser(SupportedBrowser.CHROME)
  @SupportedBrowser(SupportedBrowser.SAFARI)
  @Experimental
  Point convertPointFromPageToNode(Node node, Point point) {
    var result = _convertPointFromPageToNode(node,
        new _DomPoint(point.x, point.y));
    return new Point(result.x, result.y);
  }

  /**
   * Checks whether [convertPointFromNodeToPage] and
   * [convertPointFromPageToNode] are supported on the current platform.
   */
  static bool get supportsPointConversions => _DomPoint.supported;
$!MEMBERS

  @DomName('DOMWindow.beforeunloadEvent')
  @DocsEditable
  static const EventStreamProvider<BeforeUnloadEvent> beforeUnloadEvent =
      const _BeforeUnloadEventStreamProvider('beforeunload');

  @DomName('DOMWindow.onbeforeunload')
  @DocsEditable
  Stream<Event> get onBeforeUnload => beforeUnloadEvent.forTarget(this);
}

/**
 * Event object that is fired before the window is closed.
 *
 * The standard window close behavior can be prevented by setting the
 * [returnValue]. This will display a dialog to the user confirming that they
 * want to close the page.
 */
abstract class BeforeUnloadEvent implements Event {
  /**
   * If set to a non-null value, a dialog will be presented to the user
   * confirming that they want to close the page.
   */
  String returnValue;
}

class _BeforeUnloadEvent extends _WrappedEvent implements BeforeUnloadEvent {
  String _returnValue;

  _BeforeUnloadEvent(Event base): super(base);

  String get returnValue => _returnValue;

  void set returnValue(String value) {
    _returnValue = value;
$if DART2JS
    // FF and IE use the value as the return value, Chrome will return this from
    // the event callback function.
    if (JS('bool', '("returnValue" in #)', wrapped)) {
      JS('void', '#.returnValue = #', wrapped, value);
    }
$endif
  }
}

class _BeforeUnloadEventStreamProvider implements
    EventStreamProvider<BeforeUnloadEvent> {
  final String _eventType;

  const _BeforeUnloadEventStreamProvider(this._eventType);

  Stream<BeforeUnloadEvent> forTarget(EventTarget e, {bool useCapture: false}) {
    var controller = new StreamController(sync: true);
    var stream = new _EventStream(e, _eventType, useCapture);
    stream.listen((event) {
      var wrapped = new _BeforeUnloadEvent(event);
      controller.add(wrapped);
      return wrapped.returnValue;
    });

    return controller.stream;
  }

  String getEventType(EventTarget target) {
    return _eventType;
  }
}