[MD History] Unify query state in history-app.

chrome/browser/resources/md_history/history_list.js

 // Copyright 2015 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.
 
 Polymer({
   is: 'history-list',
 
   properties: {
-    // An array of history entries in reverse chronological order.
-    historyData: {
-      type: Array
+    // The search term for the current query. Set when the query returns.
+    searchedTerm: {
+      type: String,
+      value: '',
     },
 
-    // The time of access of the last history item in historyData.
-    lastVisitedTime: {
-      type: Number,
-      value: 0
-    },
+    lastSearchedTerm_: String,
 
-    searchTerm: {
-      type: String,
-      value: ''
-    },
+    querying: Boolean,
 
-    // True if there is a pending request to the backend.
-    loading_: {
-      type: Boolean,
-      value: true
-    },
+    // An array of history entries in reverse chronological order.
+    historyData: Array,
 
     resultLoadingDisabled_: {
       type: Boolean,
-      value: false
+      value: false,
     },
   },
 
   listeners: {
     'infinite-list.scroll': 'closeMenu_',
     'tap': 'closeMenu_',
     'toggle-menu': 'toggleMenu_',
   },
 
   /**
    * Closes the overflow menu.
    * @private
    */
   closeMenu_: function() {
     /** @type {CrSharedMenuElement} */(this.$.sharedMenu).closeMenu();
   },
 
   /**
-   * Mark the page as currently loading new data from the back-end.
-   */
-  setLoading: function() {
-    this.loading_ = true;
-  },
-
-  /**
    * Opens the overflow menu unless the menu is already open and the same button
    * is pressed.
    * @param {{detail: {item: !HistoryEntry, target: !HTMLElement}}} e
    * @private
    */
   toggleMenu_: function(e) {
     var target = e.detail.target;
     /** @type {CrSharedMenuElement} */(this.$.sharedMenu).toggleMenu(
         target, e.detail.item);
   },
 
   /** @private */
   onMoreFromSiteTap_: function() {
     var menu = /** @type {CrSharedMenuElement} */(this.$.sharedMenu);
-    this.fire('search-changed', {search: menu.itemData.domain});
+    this.fire('search-domain', {domain: menu.itemData.domain});
     menu.closeMenu();
   },
 
   /** @private */
   onRemoveFromHistoryTap_: function() {
     var menu = /** @type {CrSharedMenuElement} */(this.$.sharedMenu);
     md_history.BrowserService.getInstance()
         .deleteItems([menu.itemData])
         .then(function(items) {
           this.removeDeletedHistory_(items);
           // This unselect-all is to reset the toolbar when deleting a selected
           // item. TODO(tsergeant): Make this automatic based on observing list
           // modifications.
           this.fire('unselect-all');
         }.bind(this));
     menu.closeMenu();
   },
 
   /**
    * Disables history result loading when there are no more history results.
    */
   disableResultLoading: function() {
     this.resultLoadingDisabled_ = true;
   },
 
   /**
    * Adds the newly updated history results into historyData. Adds new fields
    * for each result.
    * @param {!Array<!HistoryEntry>} historyResults The new history results.
-   * @param {string} searchTerm Search query used to find these results.
    */
-  addNewResults: function(historyResults, searchTerm) {
-    this.loading_ = false;
+  addNewResults: function(historyResults) {
     /** @type {IronScrollThresholdElement} */(this.$['scroll-threshold'])
         .clearTriggers();
 
-    if (this.searchTerm != searchTerm) {
+    if (this.lastSearchedTerm_ != this.searchedTerm) {
       this.resultLoadingDisabled_ = false;
       if (this.historyData)
         this.splice('historyData', 0, this.historyData.length);
-      this.searchTerm = searchTerm;
+      this.lastSearchedTerm_ = this.searchedTerm;
     }
 
     if (historyResults.length == 0)
       return;
 
     // Creates a copy of historyResults to prevent accidentally modifying this
     // field.
     var results = historyResults.slice();
 
     var currentDate = results[0].dateRelativeDay;
 
     for (var i = 0; i < results.length; i++) {
       // Sets the default values for these fields to prevent undefined types.
       results[i].selected = false;
       results[i].readableTimestamp =
-          searchTerm == '' ? results[i].dateTimeOfDay : results[i].dateShort;
+          this.searchedTerm == '' ?
+              results[i].dateTimeOfDay : results[i].dateShort;
 
       if (results[i].dateRelativeDay != currentDate) {
         currentDate = results[i].dateRelativeDay;
       }
     }
 
     if (this.historyData) {
       // If we have previously received data, push the new items onto the
       // existing array.
       results.unshift('historyData');
       this.push.apply(this, results);
     } else {
       // The first time we receive data, use set() to ensure the iron-list is
       // initialized correctly.
       this.set('historyData', results);
     }
-
-    this.lastVisitedTime = this.historyData[this.historyData.length - 1].time;
   },
 
   /**
    * Cycle through each entry in historyData and set all items to be
    * unselected.
    * @param {number} overallItemCount The number of checkboxes selected.
    */
   unselectAllItems: function(overallItemCount) {
     if (this.historyData === undefined)
       return;
@@ skipping 54 matching lines @@
           this.removeDeletedHistory_(items);
           this.fire('unselect-all');
         }.bind(this));
   },
 
   /**
    * Called when the page is scrolled to near the bottom of the list.
    * @private
    */
   loadMoreData_: function() {
-    if (this.resultLoadingDisabled_ || this.loading_)
+    if (this.resultLoadingDisabled_ || this.querying)
       return;
 
-    this.loading_ = true;
-    chrome.send('queryHistory',
-        [this.searchTerm, 0, 0, this.lastVisitedTime, RESULTS_PER_PAGE]);
+    this.fire('load-more-history');
   },
 
   /**
    * Check whether the time difference between the given history item and the
    * next one is large enough for a spacer to be required.
    * @param {HistoryEntry} item
    * @param {number} index The index of |item| in |historyData|.
    * @param {number} length The length of |historyData|.
    * @return {boolean} Whether or not time gap separator is required.
    * @private
    */
   needsTimeGap_: function(item, index, length) {
     if (index >= length - 1 || length == 0)
       return false;
 
     var currentItem = this.historyData[index];
     var nextItem = this.historyData[index + 1];
 
-    if (this.searchTerm)
+    if (this.searchedTerm)
       return currentItem.dateShort != nextItem.dateShort;
 
     return currentItem.time - nextItem.time > BROWSING_GAP_TIME &&
         currentItem.dateRelativeDay == nextItem.dateRelativeDay;
   },
 
   hasResults: function(historyDataLength) {
     return historyDataLength > 0;
   },
 
-  noResultsMessage_: function(searchTerm, isLoading) {
+  noResultsMessage_: function(searchedTerm, isLoading) {
     if (isLoading)
       return '';
-    var messageId = searchTerm !== '' ? 'noSearchResults' : 'noResults';
+    var messageId = searchedTerm !== '' ? 'noSearchResults' : 'noResults';
     return loadTimeData.getString(messageId);
   },
 
   /**
    * True if the given item is the beginning of a new card.
    * @param {HistoryEntry} item
    * @param {number} i Index of |item| within |historyData|.
    * @param {number} length
    * @return {boolean}
    * @private
@@ skipping 15 matching lines @@
    * @private
    */
   isCardEnd_: function(item, i, length) {
     if (length == 0 || i > length - 1)
       return false;
     return i == length - 1 ||
         this.historyData[i].dateRelativeDay !=
         this.historyData[i + 1].dateRelativeDay;
   },
 });