1 files changed, 142 insertions, 0 deletions
diff --git a/browser/base/content/browser-thumbnails.js b/browser/base/content/browser-thumbnails.js
new file mode 100644
index 000000000..ebefb193e
--- /dev/null
+++ b/browser/base/content/browser-thumbnails.js
@@ -0,0 +1,142 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * Keeps thumbnails of open web pages up-to-date.
+ */
+var gBrowserThumbnails = {
+  /**
+   * Pref that controls whether we can store SSL content on disk
+   */
+  PREF_DISK_CACHE_SSL: "browser.cache.disk_cache_ssl",
+
+  _captureDelayMS: 1000,
+
+  /**
+   * Used to keep track of disk_cache_ssl preference
+   */
+  _sslDiskCacheEnabled: null,
+
+  /**
+   * Map of capture() timeouts assigned to their browsers.
+   */
+  _timeouts: null,
+
+  /**
+   * List of tab events we want to listen for.
+   */
+  _tabEvents: ["TabClose", "TabSelect"],
+
+  init: function Thumbnails_init() {
+    PageThumbs.addExpirationFilter(this);
+    gBrowser.addTabsProgressListener(this);
+    Services.prefs.addObserver(this.PREF_DISK_CACHE_SSL, this, false);
+
+    this._sslDiskCacheEnabled =
+      Services.prefs.getBoolPref(this.PREF_DISK_CACHE_SSL);
+
+    this._tabEvents.forEach(function (aEvent) {
+      gBrowser.tabContainer.addEventListener(aEvent, this, false);
+    }, this);
+
+    this._timeouts = new WeakMap();
+  },
+
+  uninit: function Thumbnails_uninit() {
+    PageThumbs.removeExpirationFilter(this);
+    gBrowser.removeTabsProgressListener(this);
+    Services.prefs.removeObserver(this.PREF_DISK_CACHE_SSL, this);
+
+    this._tabEvents.forEach(function (aEvent) {
+      gBrowser.tabContainer.removeEventListener(aEvent, this, false);
+    }, this);
+  },
+
+  handleEvent: function Thumbnails_handleEvent(aEvent) {
+    switch (aEvent.type) {
+      case "scroll":
+        let browser = aEvent.currentTarget;
+        if (this._timeouts.has(browser))
+          this._delayedCapture(browser);
+        break;
+      case "TabSelect":
+        this._delayedCapture(aEvent.target.linkedBrowser);
+        break;
+      case "TabClose": {
+        this._clearTimeout(aEvent.target.linkedBrowser);
+        break;
+      }
+    }
+  },
+
+  observe: function Thumbnails_observe() {
+    this._sslDiskCacheEnabled =
+      Services.prefs.getBoolPref(this.PREF_DISK_CACHE_SSL);
+  },
+
+  filterForThumbnailExpiration:
+  function Thumbnails_filterForThumbnailExpiration(aCallback) {
+    aCallback(this._topSiteURLs);
+  },
+
+  /**
+   * State change progress listener for all tabs.
+   */
+  onStateChange: function Thumbnails_onStateChange(aBrowser, aWebProgress,
+                                                   aRequest, aStateFlags, aStatus) {
+    if (aStateFlags & Ci.nsIWebProgressListener.STATE_STOP &&
+        aStateFlags & Ci.nsIWebProgressListener.STATE_IS_NETWORK)
+      this._delayedCapture(aBrowser);
+  },
+
+  _capture: function Thumbnails_capture(aBrowser) {
+    // Only capture about:newtab top sites.
+    if (this._topSiteURLs.indexOf(aBrowser.currentURI.spec) == -1)
+      return;
+    this._shouldCapture(aBrowser, function (aResult) {
+      if (aResult) {
+        PageThumbs.captureAndStoreIfStale(aBrowser);
+      }
+    });
+  },
+
+  _delayedCapture: function Thumbnails_delayedCapture(aBrowser) {
+    if (this._timeouts.has(aBrowser))
+      clearTimeout(this._timeouts.get(aBrowser));
+    else
+      aBrowser.addEventListener("scroll", this, true);
+
+    let timeout = setTimeout(function () {
+      this._clearTimeout(aBrowser);
+      this._capture(aBrowser);
+    }.bind(this), this._captureDelayMS);
+
+    this._timeouts.set(aBrowser, timeout);
+  },
+
+  _shouldCapture: function Thumbnails_shouldCapture(aBrowser, aCallback) {
+    // Capture only if it's the currently selected tab.
+    if (aBrowser != gBrowser.selectedBrowser) {
+      aCallback(false);
+      return;
+    }
+    PageThumbs.shouldStoreThumbnail(aBrowser, aCallback);
+  },
+
+  get _topSiteURLs() {
+    return NewTabUtils.links.getLinks().reduce((urls, link) => {
+      if (link)
+        urls.push(link.url);
+      return urls;
+    }, []);
+  },
+
+  _clearTimeout: function Thumbnails_clearTimeout(aBrowser) {
+    if (this._timeouts.has(aBrowser)) {
+      aBrowser.removeEventListener("scroll", this, false);
+      clearTimeout(this._timeouts.get(aBrowser));
+      this._timeouts.delete(aBrowser);
+    }
+  }
+};