/**
 * @license
 * Copyright 2015 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.player.HttpVideoSource');

goog.require('shaka.features');
goog.require('shaka.media.StreamConfig');
goog.require('shaka.player.DrmInfo');
goog.require('shaka.player.IVideoSource');
goog.require('shaka.util.EmeUtils');
goog.require('shaka.util.FakeEvent');
goog.require('shaka.util.FakeEventTarget');
goog.require('shaka.util.MapUtils');
goog.require('shaka.util.StringUtils');



/**
 * Creates an HttpVideoSource.
 * @param {string} mediaUrl The media URL.
 * @param {string} textUrl The text URL, or empty string if no subtitles.
 * @param {shaka.player.DrmInfo.Config} drmInfoConfig A DrmInfo Config object,
 *     an empty object indicates unencrypted content.
 * @struct
 * @constructor
 * @implements {shaka.player.IVideoSource}
 * @extends {shaka.util.FakeEventTarget}
 * @exportDoc
 */
shaka.player.HttpVideoSource = function(mediaUrl, textUrl, drmInfoConfig) {
  shaka.util.FakeEventTarget.call(this, null);

  /** @private {string} */
  this.mediaUrl_ = mediaUrl;

  /** @private {string} */
  this.textUrl_ = textUrl;

  /** @private {shaka.player.DrmInfo} */
  this.drmInfo_ = shaka.player.DrmInfo.createFromConfig(drmInfoConfig);

  /** @private {HTMLTrackElement} */
  this.textTrack_ = null;
};
goog.inherits(shaka.player.HttpVideoSource, shaka.util.FakeEventTarget);
if (shaka.features.Http) {
  goog.exportSymbol('shaka.player.HttpVideoSource',
                    shaka.player.HttpVideoSource);
}


/** @override */
shaka.player.HttpVideoSource.prototype.configure = function(config) {
  // nop
};


/** @override */
shaka.player.HttpVideoSource.prototype.destroy = function() {
  if (this.textTrack_) {
    this.textTrack_.parentElement.removeChild(this.textTrack_);
    this.textTrack_ = null;
  }

  this.drmInfo_ = null;
  this.parent = null;
};


/** @override */
shaka.player.HttpVideoSource.prototype.attach = function(player, video) {
  this.parent = player;

  // This fixes bug #18614098.  See comments in DashVideoSource.attach for more
  // details.
  var backupMediaKeys = video.mediaKeys;
  video.src = this.mediaUrl_;
  var restorePromise = video.setMediaKeys(backupMediaKeys);

  if (this.textUrl_) {
    this.textTrack_ = /** @type {HTMLTrackElement} */
        (document.createElement('track'));
    this.textTrack_.src = this.textUrl_;
    video.appendChild(this.textTrack_);
    // NOTE: mode must be set after appending to the DOM.
    this.textTrack_.track.mode = 'showing';
  }

  return restorePromise;
};


/** @override */
shaka.player.HttpVideoSource.prototype.load = function() {
  return Promise.resolve();
};


/** @override */
shaka.player.HttpVideoSource.prototype.getVideoTracks = function() {
  return [];
};


/** @override */
shaka.player.HttpVideoSource.prototype.getAudioTracks = function() {
  return [];
};


/** @override */
shaka.player.HttpVideoSource.prototype.getTextTracks = function() {
  return [];
};


/** @override */
shaka.player.HttpVideoSource.prototype.getBufferingGoal = function() {
  return 5.0;
};


/** @override */
shaka.player.HttpVideoSource.prototype.getConfigurations = function() {
  var cfg = new shaka.media.StreamConfig();
  cfg.drmInfo = this.drmInfo_;
  return [cfg];
};


/** @override */
shaka.player.HttpVideoSource.prototype.selectConfigurations =
    function(configs) {
  // nop
};


/** @override */
shaka.player.HttpVideoSource.prototype.selectVideoTrack =
    function(id, clearBuffer, opt_clearBufferOffset) {
  return false;
};


/** @override */
shaka.player.HttpVideoSource.prototype.selectAudioTrack =
    function(id, clearBuffer) {
  return false;
};


/** @override */
shaka.player.HttpVideoSource.prototype.selectTextTrack =
    function(id, clearBuffer) {
  return false;
};


/** @override */
shaka.player.HttpVideoSource.prototype.enableTextTrack = function(enabled) {
  if (!this.textTrack_) {
    return;
  }

  this.textTrack_.track.mode = enabled ? 'showing' : 'disabled';
};


/** @override */
shaka.player.HttpVideoSource.prototype.setPlaybackStartTime =
    function(startTime) {
  // nop
};


/** @override */
shaka.player.HttpVideoSource.prototype.getSessionIds = function() {
  return [];
};


/** @override */
shaka.player.HttpVideoSource.prototype.isOffline = function() {
  return false;
};


/** @override */
shaka.player.HttpVideoSource.prototype.isLive = function() {
  return false;
};


/** @override */
shaka.player.HttpVideoSource.prototype.onKeyStatusesChange = function(
    keyStatusByKeyId) {
  for (var keyId in keyStatusByKeyId) {
    var keyStatus = keyStatusByKeyId[keyId];
    var message = shaka.util.EmeUtils.getKeyStatusErrorMessage(keyStatus);
    if (message) {
      var prettyKeyId = shaka.util.StringUtils.formatHexString(keyId);
      var error = new Error(
          'Key ' + prettyKeyId + ' is not usable. ' + message);
      error.type = 'drm';
      error.code = keyStatus;
      var event = shaka.util.FakeEvent.createErrorEvent(error);
      this.dispatchEvent(event);
    }
  }
};