/**
* @license
* Copyright 2016 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
goog.provide('shaka.cast.CastProxy');
goog.require('goog.asserts');
goog.require('shaka.cast.CastSender');
goog.require('shaka.cast.CastUtils');
goog.require('shaka.log');
goog.require('shaka.util.Error');
goog.require('shaka.util.EventManager');
goog.require('shaka.util.FakeEvent');
goog.require('shaka.util.FakeEventTarget');
goog.require('shaka.util.IDestroyable');
/**
* A proxy to switch between local and remote playback for Chromecast in a way
* that is transparent to the app's controls.
*
* @constructor
* @struct
* @param {!HTMLMediaElement} video The local video element associated with the
* local Player instance.
* @param {!shaka.Player} player A local Player instance.
* @param {string} receiverAppId The ID of the cast receiver application.
* @implements {shaka.util.IDestroyable}
* @extends {shaka.util.FakeEventTarget}
* @export
*/
shaka.cast.CastProxy = function(video, player, receiverAppId) {
shaka.util.FakeEventTarget.call(this);
/** @private {HTMLMediaElement} */
this.localVideo_ = video;
/** @private {shaka.Player} */
this.localPlayer_ = player;
/** @private {Object} */
this.videoProxy_ = null;
/** @private {Object} */
this.playerProxy_ = null;
/** @private {shaka.util.FakeEventTarget} */
this.videoEventTarget_ = null;
/** @private {shaka.util.FakeEventTarget} */
this.playerEventTarget_ = null;
/** @private {shaka.util.EventManager} */
this.eventManager_ = null;
/** @private {shaka.cast.CastSender} */
this.sender_ = new shaka.cast.CastSender(
receiverAppId,
this.onCastStatusChanged_.bind(this),
this.onFirstCastStateUpdate_.bind(this),
this.onRemoteEvent_.bind(this),
this.onResumeLocal_.bind(this),
this.getInitState_.bind(this));
this.init_();
};
goog.inherits(shaka.cast.CastProxy, shaka.util.FakeEventTarget);
/**
* Destroys the proxy and the underlying local Player.
*
* @param {boolean=} opt_forceDisconnect If true, force the receiver app to shut
* down by disconnecting. Does nothing if not connected.
* @override
* @export
*/
shaka.cast.CastProxy.prototype.destroy = function(opt_forceDisconnect) {
if (opt_forceDisconnect && this.sender_) {
this.sender_.forceDisconnect();
}
let async = [
this.eventManager_ ? this.eventManager_.destroy() : null,
this.localPlayer_ ? this.localPlayer_.destroy() : null,
this.sender_ ? this.sender_.destroy() : null
];
this.localVideo_ = null;
this.localPlayer_ = null;
this.videoProxy_ = null;
this.playerProxy_ = null;
this.eventManager_ = null;
this.sender_ = null;
return Promise.all(async);
};
/**
* @event shaka.cast.CastProxy.CastStatusChangedEvent
* @description Fired when cast status changes. The status change will be
* reflected in canCast() and isCasting().
* @property {string} type
* 'caststatuschanged'
* @exportDoc
*/
/**
* Get a proxy for the video element that delegates to local and remote video
* elements as appropriate.
*
* @suppress {invalidCasts} to cast proxy Objects to unrelated types
* @return {HTMLMediaElement}
* @export
*/
shaka.cast.CastProxy.prototype.getVideo = function() {
return /** @type {HTMLMediaElement} */(this.videoProxy_);
};
/**
* Get a proxy for the Player that delegates to local and remote Player objects
* as appropriate.
*
* @suppress {invalidCasts} to cast proxy Objects to unrelated types
* @return {shaka.Player}
* @export
*/
shaka.cast.CastProxy.prototype.getPlayer = function() {
return /** @type {shaka.Player} */(this.playerProxy_);
};
/**
* @return {boolean} True if the cast API is available and there are receivers.
* @export
*/
shaka.cast.CastProxy.prototype.canCast = function() {
return this.sender_ ?
this.sender_.apiReady() && this.sender_.hasReceivers() :
false;
};
/**
* @return {boolean} True if we are currently casting.
* @export
*/
shaka.cast.CastProxy.prototype.isCasting = function() {
return this.sender_ ? this.sender_.isCasting() : false;
};
/**
* @return {string} The name of the Cast receiver device, if isCasting().
* @export
*/
shaka.cast.CastProxy.prototype.receiverName = function() {
return this.sender_ ? this.sender_.receiverName() : '';
};
/**
* @return {!Promise} Resolved when connected to a receiver. Rejected if the
* connection fails or is canceled by the user.
* @export
*/
shaka.cast.CastProxy.prototype.cast = function() {
let initState = this.getInitState_();
// TODO: transfer manually-selected tracks?
// TODO: transfer side-loaded text tracks?
return this.sender_.cast(initState).then(function() {
if (!this.localPlayer_) {
// We've already been destroyed.
return;
}
// Unload the local manifest when casting succeeds.
return this.localPlayer_.unload();
}.bind(this));
};
/**
* Set application-specific data.
*
* @param {Object} appData Application-specific data to relay to the receiver.
* @export
*/
shaka.cast.CastProxy.prototype.setAppData = function(appData) {
this.sender_.setAppData(appData);
};
/**
* Show a dialog where user can choose to disconnect from the cast connection.
* @export
*/
shaka.cast.CastProxy.prototype.suggestDisconnect = function() {
this.sender_.showDisconnectDialog();
};
/**
* Force the receiver app to shut down by disconnecting.
* @export
*/
shaka.cast.CastProxy.prototype.forceDisconnect = function() {
this.sender_.forceDisconnect();
};
/**
* Initialize the Proxies and the Cast sender.
* @private
*/
shaka.cast.CastProxy.prototype.init_ = function() {
this.sender_.init();
this.eventManager_ = new shaka.util.EventManager();
shaka.cast.CastUtils.VideoEvents.forEach(function(name) {
this.eventManager_.listen(this.localVideo_, name,
this.videoProxyLocalEvent_.bind(this));
}.bind(this));
shaka.cast.CastUtils.PlayerEvents.forEach(function(name) {
this.eventManager_.listen(this.localPlayer_, name,
this.playerProxyLocalEvent_.bind(this));
}.bind(this));
// We would like to use Proxy here, but it is not supported on IE11 or Safari.
this.videoProxy_ = {};
for (let k in this.localVideo_) {
Object.defineProperty(this.videoProxy_, k, {
configurable: false,
enumerable: true,
get: this.videoProxyGet_.bind(this, k),
set: this.videoProxySet_.bind(this, k)
});
}
this.playerProxy_ = {};
for (let k in /** @type {Object} */(this.localPlayer_)) {
Object.defineProperty(this.playerProxy_, k, {
configurable: false,
enumerable: true,
get: this.playerProxyGet_.bind(this, k)
});
}
this.videoEventTarget_ = new shaka.util.FakeEventTarget();
this.videoEventTarget_.dispatchTarget =
/** @type {EventTarget} */(this.videoProxy_);
this.playerEventTarget_ = new shaka.util.FakeEventTarget();
this.playerEventTarget_.dispatchTarget =
/** @type {EventTarget} */(this.playerProxy_);
};
/**
* @return {shaka.cast.CastUtils.InitStateType} initState Video and player state
* to be sent to the receiver.
* @private
*/
shaka.cast.CastProxy.prototype.getInitState_ = function() {
let initState = {
'video': {},
'player': {},
'playerAfterLoad': {},
'manifest': this.localPlayer_.getManifestUri(),
'startTime': null
};
// Pause local playback before capturing state.
this.localVideo_.pause();
shaka.cast.CastUtils.VideoInitStateAttributes.forEach(function(name) {
initState['video'][name] = this.localVideo_[name];
}.bind(this));
// If the video is still playing, set the startTime.
// Has no effect if nothing is loaded.
if (!this.localVideo_.ended) {
initState['startTime'] = this.localVideo_.currentTime;
}
shaka.cast.CastUtils.PlayerInitState.forEach(function(pair) {
let getter = pair[0];
let setter = pair[1];
let value = /** @type {Object} */(this.localPlayer_)[getter]();
initState['player'][setter] = value;
}.bind(this));
shaka.cast.CastUtils.PlayerInitAfterLoadState.forEach(function(pair) {
let getter = pair[0];
let setter = pair[1];
let value = /** @type {Object} */(this.localPlayer_)[getter]();
initState['playerAfterLoad'][setter] = value;
}.bind(this));
return initState;
};
/**
* Dispatch an event to notify the app that the status has changed.
* @private
*/
shaka.cast.CastProxy.prototype.onCastStatusChanged_ = function() {
let event = new shaka.util.FakeEvent('caststatuschanged');
this.dispatchEvent(event);
};
/**
* Dispatch a synthetic play or pause event to ensure that the app correctly
* knows that the player is playing, if joining an existing receiver.
* @private
*/
shaka.cast.CastProxy.prototype.onFirstCastStateUpdate_ = function() {
let type = this.videoProxy_.paused ? 'pause' : 'play';
let fakeEvent = new shaka.util.FakeEvent(type);
this.videoEventTarget_.dispatchEvent(fakeEvent);
};
/**
* Transfer remote state back and resume local playback.
* @private
*/
shaka.cast.CastProxy.prototype.onResumeLocal_ = function() {
// Transfer back the player state.
shaka.cast.CastUtils.PlayerInitState.forEach(function(pair) {
let getter = pair[0];
let setter = pair[1];
let value = this.sender_.get('player', getter)();
/** @type {Object} */(this.localPlayer_)[setter](value);
}.bind(this));
// Get the most recent manifest URI and ended state.
let manifestUri = this.sender_.get('player', 'getManifestUri')();
let ended = this.sender_.get('video', 'ended');
let manifestReady = Promise.resolve();
let autoplay = this.localVideo_.autoplay;
let startTime = null;
// If the video is still playing, set the startTime.
// Has no effect if nothing is loaded.
if (!ended) {
startTime = this.sender_.get('video', 'currentTime');
}
// Now load the manifest, if present.
if (manifestUri) {
// Don't autoplay the content until we finish setting up initial state.
this.localVideo_.autoplay = false;
manifestReady = this.localPlayer_.load(manifestUri, startTime);
}
// Get the video state into a temp variable since we will apply it async.
let videoState = {};
shaka.cast.CastUtils.VideoInitStateAttributes.forEach(function(name) {
videoState[name] = this.sender_.get('video', name);
}.bind(this));
// Finally, take on video state and player's "after load" state.
manifestReady.then(() => {
if (!this.localVideo_) {
// We've already been destroyed.
return;
}
shaka.cast.CastUtils.VideoInitStateAttributes.forEach(function(name) {
this.localVideo_[name] = videoState[name];
}.bind(this));
shaka.cast.CastUtils.PlayerInitAfterLoadState.forEach(function(pair) {
let getter = pair[0];
let setter = pair[1];
let value = this.sender_.get('player', getter)();
/** @type {Object} */(this.localPlayer_)[setter](value);
}.bind(this));
// Restore the original autoplay setting.
this.localVideo_.autoplay = autoplay;
if (manifestUri) {
// Resume playback with transferred state.
this.localVideo_.play();
}
}, (error) => {
// Pass any errors through to the app.
goog.asserts.assert(error instanceof shaka.util.Error,
'Wrong error type!');
let event = new shaka.util.FakeEvent('error', {'detail': error});
this.localPlayer_.dispatchEvent(event);
});
};
/**
* @param {string} name
* @return {?}
* @private
*/
shaka.cast.CastProxy.prototype.videoProxyGet_ = function(name) {
if (name == 'addEventListener') {
return this.videoEventTarget_.addEventListener.bind(
this.videoEventTarget_);
}
if (name == 'removeEventListener') {
return this.videoEventTarget_.removeEventListener.bind(
this.videoEventTarget_);
}
// If we are casting, but the first update has not come in yet, use local
// values, but not local methods.
if (this.sender_.isCasting() && !this.sender_.hasRemoteProperties()) {
let value = this.localVideo_[name];
if (typeof value != 'function') {
return value;
}
}
// Use local values and methods if we are not casting.
if (!this.sender_.isCasting()) {
let value = this.localVideo_[name];
if (typeof value == 'function') {
value = value.bind(this.localVideo_);
}
return value;
}
return this.sender_.get('video', name);
};
/**
* @param {string} name
* @param {?} value
* @private
*/
shaka.cast.CastProxy.prototype.videoProxySet_ = function(name, value) {
if (!this.sender_.isCasting()) {
this.localVideo_[name] = value;
return;
}
this.sender_.set('video', name, value);
};
/**
* @param {!Event} event
* @private
*/
shaka.cast.CastProxy.prototype.videoProxyLocalEvent_ = function(event) {
if (this.sender_.isCasting()) {
// Ignore any unexpected local events while casting. Events can still be
// fired by the local video and Player when we unload() after the Cast
// connection is complete.
return;
}
// Convert this real Event into a FakeEvent for dispatch from our
// FakeEventListener.
let fakeEvent = new shaka.util.FakeEvent(event.type, event);
this.videoEventTarget_.dispatchEvent(fakeEvent);
};
/**
* @param {string} name
* @return {?}
* @private
*/
shaka.cast.CastProxy.prototype.playerProxyGet_ = function(name) {
if (name == 'addEventListener') {
return this.playerEventTarget_.addEventListener.bind(
this.playerEventTarget_);
}
if (name == 'removeEventListener') {
return this.playerEventTarget_.removeEventListener.bind(
this.playerEventTarget_);
}
if (name == 'getMediaElement') {
return function() { return this.videoProxy_; }.bind(this);
}
if (name == 'getNetworkingEngine') {
// Always returns a local instance, in case you need to make a request.
// Issues a warning, in case you think you are making a remote request
// or affecting remote filters.
if (this.sender_.isCasting()) {
shaka.log.warning('NOTE: getNetworkingEngine() is always local!');
}
return this.localPlayer_.getNetworkingEngine.bind(this.localPlayer_);
}
if (this.sender_.isCasting()) {
// These methods are unavailable or otherwise stubbed during casting.
if (name == 'getManifest') {
return function() {
shaka.log.alwaysWarn('getManifest() does not work while casting!');
return null;
};
}
if (name == 'attach') {
return function() {
shaka.log.alwaysWarn('attach() does not work while casting!');
return Promise.resolve();
};
}
if (name == 'detach') {
return function() {
shaka.log.alwaysWarn('detach() does not work while casting!');
return Promise.resolve();
};
}
} // if (this.sender_.isCasting())
// If we are casting, but the first update has not come in yet, use local
// getters, but not local methods.
if (this.sender_.isCasting() && !this.sender_.hasRemoteProperties()) {
if (shaka.cast.CastUtils.PlayerGetterMethods[name]) {
let value = /** @type {Object} */(this.localPlayer_)[name];
goog.asserts.assert(typeof value == 'function', 'only methods on Player');
return value.bind(this.localPlayer_);
}
}
// Use local getters and methods if we are not casting.
if (!this.sender_.isCasting()) {
let value = /** @type {Object} */(this.localPlayer_)[name];
goog.asserts.assert(typeof value == 'function', 'only methods on Player');
return value.bind(this.localPlayer_);
}
return this.sender_.get('player', name);
};
/**
* @param {!Event} event
* @private
*/
shaka.cast.CastProxy.prototype.playerProxyLocalEvent_ = function(event) {
if (this.sender_.isCasting()) {
// Ignore any unexpected local events while casting.
return;
}
this.playerEventTarget_.dispatchEvent(event);
};
/**
* @param {string} targetName
* @param {!shaka.util.FakeEvent} event
* @private
*/
shaka.cast.CastProxy.prototype.onRemoteEvent_ = function(targetName, event) {
goog.asserts.assert(this.sender_.isCasting(),
'Should only receive remote events while casting');
if (!this.sender_.isCasting()) {
// Ignore any unexpected remote events.
return;
}
if (targetName == 'video') {
this.videoEventTarget_.dispatchEvent(event);
} else if (targetName == 'player') {
this.playerEventTarget_.dispatchEvent(event);
}
};