/**
* @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.CastUtils');
goog.require('shaka.util.FakeEvent');
/**
* @namespace shaka.cast.CastUtils
* @summary A set of cast utility functions and variables shared between sender
* and receiver.
*/
/**
* HTMLMediaElement events that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.VideoEvents = [
'ended',
'play',
'playing',
'pause',
'pausing',
'ratechange',
'seeked',
'seeking',
'timeupdate',
'volumechange'
];
/**
* HTMLMediaElement attributes that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.VideoAttributes = [
'buffered',
'currentTime',
'duration',
'ended',
'loop',
'muted',
'paused',
'playbackRate',
'seeking',
'videoHeight',
'videoWidth',
'volume'
];
/**
* HTMLMediaElement attributes that are transferred when casting begins.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.VideoInitStateAttributes = [
'loop',
'playbackRate'
];
/**
* HTMLMediaElement methods with no return value that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.VideoVoidMethods = [
'pause',
'play'
];
/**
* Player events that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.PlayerEvents = [
'adaptation',
'buffering',
'emsg',
'error',
'loading',
'streaming',
'texttrackvisibility',
'timelineregionadded',
'timelineregionenter',
'timelineregionexit',
'trackschanged',
'unloading'
];
/**
* Player getter methods that are proxied while casting.
* The key is the method, the value is the frequency of updates.
* Frequency 1 translates to every update; frequency 2 to every 2 updates, etc.
* @const {!Object.<string, number>}
*/
shaka.cast.CastUtils.PlayerGetterMethods = {
'drmInfo': 20,
'getAudioLanguages': 2,
'getAudioLanguagesAndRoles': 2,
'getBufferedInfo': 2,
'getConfiguration': 2,
'getExpiration': 2,
// Note that the 'getManifest' property is not proxied, as it is very large.
'getManifestUri': 2,
'getPlaybackRate': 2,
'getTextLanguages': 2,
'getTextLanguagesAndRoles': 2,
'getTextTracks': 2,
'getStats': 5,
'getVariantTracks': 2,
'isAudioOnly': 10,
'isBuffering': 1,
'isInProgress': 1,
'isLive': 10,
'isTextTrackVisible': 1,
'keySystem': 10,
'seekRange': 1
};
/**
* Player getter methods that are proxied while casting, but only when casting
* a livestream.
* The key is the method, the value is the frequency of updates.
* Frequency 1 translates to every update; frequency 2 to every 2 updates, etc.
* @const {!Object.<string, number>}
*/
shaka.cast.CastUtils.PlayerGetterMethodsThatRequireLive = {
'getPlayheadTimeAsDate': 1,
'getPresentationStartTimeAsDate': 20
};
/**
* Player getter and setter methods that are used to transfer state when casting
* begins.
* @const {!Array.<!Array.<string>>}
*/
shaka.cast.CastUtils.PlayerInitState = [
['getConfiguration', 'configure']
];
/**
* Player getter and setter methods that are used to transfer state after
* after load() is resolved.
* @const {!Array.<!Array.<string>>}
*/
shaka.cast.CastUtils.PlayerInitAfterLoadState = [
['isTextTrackVisible', 'setTextTrackVisibility']
];
/**
* Player methods with no return value that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.PlayerVoidMethods = [
'addTextTrack',
'cancelTrickPlay',
'configure',
'resetConfiguration',
'retryStreaming',
'selectAudioLanguage',
'selectTextLanguage',
'selectTextTrack',
'selectVariantTrack',
'setTextTrackVisibility',
'trickPlay'
];
/**
* Player methods returning a Promise that are proxied while casting.
* @const {!Array.<string>}
*/
shaka.cast.CastUtils.PlayerPromiseMethods = [
// The opt_manifestFactory parameter of load is not supported.
'load',
'unload'
];
/**
* @typedef {{
* video: Object,
* player: Object,
* manifest: ?string,
* startTime: ?number
* }}
* @property {Object} video
* Dictionary of video properties to be set.
* @property {Object} player
* Dictionary of player setters to be called.
* @property {?string} manifest
* The currently-selected manifest, if present.
* @property {?number} startTime
* The playback start time, if currently playing.
*/
shaka.cast.CastUtils.InitStateType;
/**
* The namespace for Shaka messages on the cast bus.
* @const {string}
*/
shaka.cast.CastUtils.SHAKA_MESSAGE_NAMESPACE = 'urn:x-cast:com.google.shaka.v2';
/**
* The namespace for generic messages on the cast bus.
* @const {string}
*/
shaka.cast.CastUtils.GENERIC_MESSAGE_NAMESPACE =
'urn:x-cast:com.google.cast.media';
/**
* Serialize as JSON, but specially encode things JSON will not otherwise
* represent.
* @param {?} thing
* @return {string}
*/
shaka.cast.CastUtils.serialize = function(thing) {
return JSON.stringify(thing, function(key, value) {
if (typeof value == 'function') {
// Functions can't be (safely) serialized.
return undefined;
}
if (value instanceof Event || value instanceof shaka.util.FakeEvent) {
// Events don't serialize to JSON well because of the DOM objects
// and other complex objects they contain. So we strip these out.
// Note that using Object.keys or JSON.stringify directly on the event
// will not capture its properties. We must use a for loop.
var simpleEvent = {};
for (var eventKey in value) {
var eventValue = value[eventKey];
if (eventValue && typeof eventValue == 'object') {
if (eventKey == 'detail') {
// Keep the detail value, because it contains important information
// for diagnosing errors.
simpleEvent[eventKey] = eventValue;
}
// Strip out non-null object types because they are complex and we
// don't need them.
} else if (eventKey in Event) {
// Strip out keys that are found on Event itself because they are
// class-level constants we don't need, like Event.MOUSEMOVE == 16.
} else {
simpleEvent[eventKey] = eventValue;
}
}
return simpleEvent;
}
if (value instanceof TimeRanges) {
// TimeRanges must be unpacked into plain data for serialization.
return shaka.cast.CastUtils.unpackTimeRanges_(value);
}
if (typeof value == 'number') {
// NaN and infinity cannot be represented directly in JSON.
if (isNaN(value)) return 'NaN';
if (isFinite(value)) return value;
if (value < 0) return '-Infinity';
return 'Infinity';
}
return value;
});
};
/**
* Deserialize JSON using our special encodings.
* @param {string} str
* @return {?}
*/
shaka.cast.CastUtils.deserialize = function(str) {
return JSON.parse(str, function(key, value) {
if (value == 'NaN') {
return NaN;
} else if (value == '-Infinity') {
return -Infinity;
} else if (value == 'Infinity') {
return Infinity;
} else if (value && typeof value == 'object' &&
value['__type__'] == 'TimeRanges') {
// TimeRanges objects have been unpacked and sent as plain data.
// Simulate the original TimeRanges object.
return shaka.cast.CastUtils.simulateTimeRanges_(value);
}
return value;
});
};
/**
* @param {!TimeRanges} ranges
* @return {Object}
* @private
*/
shaka.cast.CastUtils.unpackTimeRanges_ = function(ranges) {
var obj = {
'__type__': 'TimeRanges', // a signal to deserialize
'length': ranges.length,
'start': [],
'end': []
};
for (var i = 0; i < ranges.length; ++i) {
obj['start'].push(ranges.start(i));
obj['end'].push(ranges.end(i));
}
return obj;
};
/**
* Creates a simulated TimeRanges object from data sent by the cast receiver.
* @param {?} obj
* @return {{
* length: number,
* start: function(number): number,
* end: function(number): number
* }}
* @private
*/
shaka.cast.CastUtils.simulateTimeRanges_ = function(obj) {
return {
length: obj.length,
// NOTE: a more complete simulation would throw when |i| was out of range,
// but for simplicity we will assume a well-behaved application that uses
// length instead of catch to stop iterating.
start: function(i) { return obj.start[i]; },
end: function(i) { return obj.end[i]; }
};
};