[Files.app] Change sort timing during metadata fetch

Previously, sort was not started until all the metadata is fetched. When fetching took a time, the user saw unsorted list for a while. With this patch, sort is happened just after every updates. User can see sorted list every time.

BUG=327479
TEST=manually tested

Review URL: https://codereview.chromium.org/113293007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@243816 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/resources/file_manager/foreground/js/directory_contents.js

@@ -460,7 +460,6 @@ function DirectoryContents(context, isSearch, directoryEntry,
   this.scanner_ = null;
   this.prefetchMetadataQueue_ = new AsyncUtil.Queue();
   this.scanCancelled_ = false;
-  this.fileList_.prepareSort = this.prepareSort_.bind(this);
 }
 
 /**
@@ -483,8 +482,11 @@ DirectoryContents.prototype.clone = function() {
  * @param {Array|cr.ui.ArrayDataModel} fileList The new file list.
  */
 DirectoryContents.prototype.setFileList = function(fileList) {
-  this.fileList_ = fileList;
-  this.fileList_.prepareSort = this.prepareSort_.bind(this);
+  if (fileList instanceof cr.ui.ArrayDataModel)
+    this.fileList_ = fileList;
+  else
+    this.fileList_ = new cr.ui.ArrayDataModel(fileList);
+  this.context_.metadataCache.setCacheSize(this.fileList_.length);
 };
 
 /**
@@ -493,11 +495,12 @@ DirectoryContents.prototype.setFileList = function(fileList) {
  */
 DirectoryContents.prototype.replaceContextFileList = function() {
   if (this.context_.fileList !== this.fileList_) {
-    var spliceArgs = [].slice.call(this.fileList_);
+    var spliceArgs = this.fileList_.slice();
     var fileList = this.context_.fileList;
     spliceArgs.unshift(0, fileList.length);
     fileList.splice.apply(fileList, spliceArgs);
     this.fileList_ = fileList;
+    this.context_.metadataCache.setCacheSize(this.fileList_.length);
   }
 };
 
@@ -605,6 +608,8 @@ DirectoryContents.prototype.onNewEntries_ = function(entries) {
   this.fileList_.push.apply(this.fileList_, entriesFiltered);
   cr.dispatchSimpleEvent(this, 'scan-updated');
 
+  this.context_.metadataCache.setCacheSize(this.fileList_.length);
+
   // Because the prefetchMetadata can be slow, throttling by splitting entries
   // into smaller chunks to reduce UI latency.
   // TODO(hidehiko,mtomasz): This should be handled in MetadataCache.
@@ -619,6 +624,16 @@ DirectoryContents.prototype.onNewEntries_ = function(entries) {
           return;
         }
 
+        // TODO(yoshiki): Here we should fire the update event of changed
+        // items. Currently we have a method this.fileList_.updateIndex() to
+        // fire an event, but this method takes only 1 argument and invokes sort
+        // one by one. It is obviously time wasting. Instead, we call sort
+        // directory.
+        // In future, we should implement a good method like updateIndexes and
+        // use it here.
+        var status = this.fileList_.sortStatus;
+        this.fileList_.sort(status.field, status.direction);
+
         cr.dispatchSimpleEvent(this, 'scan-updated');
         callback();
       }.bind(this));
@@ -626,19 +641,6 @@ DirectoryContents.prototype.onNewEntries_ = function(entries) {
   }
 };
 
-/**
- * Cache necessary data before a sort happens.
- *
- * This is called by the table code before a sort happens, so that we can
- * go fetch data for the sort field that we may not have yet.
- * @param {string} field Sort field.
- * @param {function(Object)} callback Called when done.
- * @private
- */
-DirectoryContents.prototype.prepareSort_ = function(field, callback) {
-  this.prefetchMetadata(this.fileList_.slice(), callback);
-};
-
 /**
  * @param {Array.<Entry>} entries Files.
  * @param {function(Object)} callback Callback on done.

chrome/browser/resources/file_manager/foreground/js/file_manager.js

@@ -2605,7 +2605,6 @@ var BOTTOM_MARGIN_FOR_PREVIEW_PANEL_PX = 52;
     if (this.commandHandler)
       this.commandHandler.updateAvailability();
     this.hideSpinnerLater_();
-    this.refreshCurrentDirectoryMetadata_();
 
     if (this.scanUpdatedTimer_) {
       clearTimeout(this.scanUpdatedTimer_);
@@ -2697,7 +2696,6 @@ var BOTTOM_MARGIN_FOR_PREVIEW_PANEL_PX = 52;
    * @private
    */
   FileManager.prototype.onRescanCompleted_ = function() {
-    this.refreshCurrentDirectoryMetadata_();
     this.selectionHandler_.onFileSelectionChanged();
   };
 

chrome/browser/resources/file_manager/foreground/js/metadata/metadata_cache.js

@@ -76,6 +76,8 @@ function MetadataCache() {
   this.batchCount_ = 0;
   this.totalCount_ = 0;
 
+  this.currentCacheSize_ = 0;
+
   /**
    * Time of first get query of the current batch. Items updated later than this
    * will not be evicted.
@@ -103,9 +105,9 @@ MetadataCache.CHILDREN = 1;
 MetadataCache.DESCENDANTS = 2;
 
 /**
- * Minimum number of items in cache to start eviction.
+ * Margin of the cache size. This amount of caches may be kept in addition.
  */
-MetadataCache.EVICTION_NUMBER = 1000;
+MetadataCache.EVICTION_THRESHOLD_MARGIN = 500;
 
 /**
  * @param {VolumeManagerWrapper} volumeManager Volume manager instance.
@@ -158,6 +160,28 @@ MetadataCache.prototype.isInitialized = function() {
   return true;
 };
 
+/**
+ * Sets the size of cache. The actual cache size may be larger than the given
+ * value.
+ * @param {number} size The cache size to be set.
+ */
+MetadataCache.prototype.setCacheSize = function(size) {
+  this.currentCacheSize_ = size;
+
+  if (this.totalCount_ > this.currentEvictionThreshold_())
+    this.evict_();
+};
+
+/**
+ * Returns the current threshold to evict caches. When the number of caches
+ * exceeds this, the cache should be evicted.
+ * @return {number} Threshold to evict caches.
+ * @private
+ */
+MetadataCache.prototype.currentEvictionThreshold_ = function() {
+  return this.currentCacheSize_ * 2 + MetadataCache.EVICTION_THRESHOLD_MARGIN;
+};
+
 /**
  * Fetches the metadata, puts it in the cache, and passes to callback.
  * If required metadata is already in the cache, does not fetch it again.
@@ -458,7 +482,7 @@ MetadataCache.prototype.startBatchUpdates = function() {
 MetadataCache.prototype.endBatchUpdates = function() {
   this.batchCount_--;
   if (this.batchCount_ !== 0) return;
-  if (this.totalCount_ > MetadataCache.EVICTION_NUMBER)
+  if (this.totalCount_ > this.currentEvictionThreshold_())
     this.evict_();
   for (var index = 0; index < this.observers_.length; index++) {
     var observer = this.observers_[index];
@@ -513,7 +537,7 @@ MetadataCache.prototype.evict_ = function() {
   var toRemove = [];
 
   // We leave only a half of items, so we will not call evict_ soon again.
-  var desiredCount = Math.round(MetadataCache.EVICTION_NUMBER / 2);
+  var desiredCount = this.currentEvictionThreshold();
   var removeCount = this.totalCount_ - desiredCount;
   for (var url in this.cache_) {
     if (this.cache_.hasOwnProperty(url) &&