[filemanager] Content metadata moved to the cache.

chrome/browser/resources/file_manager/js/media/audio_player.js

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 document.addEventListener('DOMContentLoaded', function() {
   // Test harness sets the search string to prevent the automatic load.
   // It calls AudioPlayer.load() explicitly after initializing
   // the |chrome| variable with an appropriate mock object.
   if (!document.location.search) {
     AudioPlayer.load();
   }
 });
 
 /**
  * @param {HTMLElement} container
  * @param {string} filesystemRootURL
  * @constructor
  */
 function AudioPlayer(container, filesystemRootURL) {
   this.container_ = container;
-  this.metadataProvider_ = new MetadataProvider(filesystemRootURL);
+  this.metadataCache_ = MetadataCache.createFull();
   this.currentTrack_ = -1;
   this.playlistGeneration_ = 0;
 
   this.container_.classList.add('collapsed');
 
   function createChild(opt_className, opt_tag) {
     var child = container.ownerDocument.createElement(opt_tag || 'div');
     if (opt_className)
       child.className = opt_className;
     container.appendChild(child);
@@ skipping 13 matching lines @@
       'click', this.onExpandCollapse_.bind(this));
 
   this.audioControls_ = new AudioControls(
       createChild(), this.advance_.bind(this), this.onError_.bind(this));
 
   this.audioControls_.attachMedia(createChild('', 'audio'));
 
   chrome.fileBrowserPrivate.getStrings(function(strings) {
     container.ownerDocument.title = strings['AUDIO_PLAYER_TITLE'];
     this.errorString_ = strings['AUDIO_ERROR'];
+    AudioPlayer.TrackInfo.DEFAULT_ARTIST =
+        strings['AUDIO_PLAYER_DEFAULT_ARTIST'];
   }.bind(this));
 }
 
 AudioPlayer.load = function() {
   document.ondragstart = function(e) { e.preventDefault() };
   document.oncontextmenu = function(e) { e.preventDefault(); };
 
   chrome.fileBrowserPrivate.requestLocalFileSystem(function(filesystem) {
     var player = new AudioPlayer(document.querySelector('.audio-player'),
         filesystem.root.toURL());
@@ skipping 68 matching lines @@
   this.changeSelectionInList_(this.currentTrack_, newTrack);
   this.changeSelectionInStack_(this.currentTrack_, newTrack);
 
   this.currentTrack_ = newTrack;
   this.scrollToCurrent_(false);
 
   var url = this.urls_[this.currentTrack_];
   this.fetchMetadata_(url, function(metadata) {
     var media = this.audioControls_.getMedia();
     // Do not try no stream when offline.
-    media.src = (navigator.onLine && metadata.streamingURL) || url;
+    media.src =
+        (navigator.onLine && metadata.streaming && metadata.streaming.url) ||
+        url;
     media.load();
     this.audioControls_.play();
   }.bind(this));
 };
 
 AudioPlayer.prototype.fetchMetadata_ = function(url, callback) {
-  this.metadataProvider_.fetch(
-      url,
+  this.metadataCache_.get(url, 'thumbnail|media|streaming',
       function(generation, metadata) {
         // Do nothing if another load happened since the metadata request.
         if (this.playlistGeneration_ == generation)
           callback(metadata);
       }.bind(this, this.playlistGeneration_));
 };
 
 AudioPlayer.prototype.changeSelectionInList_ = function(oldTrack, newTrack) {
   this.trackListItems_[newTrack].getBox().classList.add('selected');
 
@@ skipping 51 matching lines @@
 
 AudioPlayer.prototype.onError_ = function() {
   var track = this.currentTrack_;
 
   this.invalidTracks_[track] = true;
 
   this.fetchMetadata_(
       this.urls_[track],
       function(metadata) {
         metadata.error = true;
-        metadata.artist = this.errorString_;
+        metadata.media = { artist: this.errorString_ };
         this.displayMetadata_(track, metadata);
         this.scheduleAutoAdvance_();
       }.bind(this));
 };
 
 AudioPlayer.prototype.scheduleAutoAdvance_ = function() {
   this.cancelAutoAdvance_();
   this.autoAdvanceTimer_ = setTimeout(
       function() {
         this.autoAdvanceTimer_ = null;
@@ skipping 78 matching lines @@
 
 AudioPlayer.TrackInfo.prototype.getBox = function() { return this.box_ };
 
 AudioPlayer.TrackInfo.prototype.getDefaultTitle = function() {
   var title = this.url_.split('/').pop();
   var dotIndex = title.lastIndexOf('.');
   if (dotIndex >= 0) title = title.substr(0, dotIndex);
   return title;
 };
 
+AudioPlayer.TrackInfo.DEFAULT_ARTIST = 'Unknown Artist';
+
 AudioPlayer.TrackInfo.prototype.getDefaultArtist = function() {
-  return 'Unknown Artist';  // TODO(kaznacheev): i18n
+  return AudioPlayer.TrackInfo.DEFAULT_ARTIST;
 };
 
 /**
- * @param {Object} metadata The metadata object
+ * @param {Object} metadata The metadata object.
  * @param {HTMLElement} container The container for the tracks.
  */
 AudioPlayer.TrackInfo.prototype.setMetadata = function(metadata, container) {
   if (metadata.error) {
     this.art_.classList.add('blank');
     this.art_.classList.add('error');
     container.classList.remove('noart');
-  } else if (metadata.thumbnailURL) {
+  } else if (metadata.thumbnail && metadata.thumbnail.url) {
     this.img_.onload = function() {
       // Only display the image if the thumbnail loaded successfully.
       this.art_.classList.remove('blank');
       container.classList.remove('noart');
     }.bind(this);
-    this.img_.src = metadata.thumbnailURL;
+    this.img_.src = metadata.thumbnail.url;
   }
-  this.title_.textContent = metadata.title || this.getDefaultTitle();
-  this.artist_.textContent = metadata.artist || this.getDefaultArtist();
+  this.title_.textContent = metadata.media.title || this.getDefaultTitle();
+  this.artist_.textContent = metadata.media.artist || this.getDefaultArtist();
 };