[gnome-shell] BluetoothStatus: update only devices that actually changed

[Giovanni Campagna <gcampagna src gnome org>]

commit 5f212b1ae2dd2685ccb55294da9bb929db211f39
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Tue Dec 21 16:26:26 2010 +0100

    BluetoothStatus: update only devices that actually changed
    
    When receiving a "devices-changed" signal from BluetoothApplet,
    check if some device item corresponds to an existing one, destroy
    the remaining and add the new ones.
    With this patch, signal emission when no device actually changed
    (which happen due to bluetoothd creating temporary devices) result
    in a no-op.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=637690

 js/ui/status/bluetooth.js |   47 +++++++++++++++++++++++++++++++++++++++-----
 1 files changed, 41 insertions(+), 6 deletions(-)
---
diff --git a/js/ui/status/bluetooth.js b/js/ui/status/bluetooth.js
index f2cfa8f..47a7ed2 100644
--- a/js/ui/status/bluetooth.js
+++ b/js/ui/status/bluetooth.js
@@ -68,6 +68,7 @@ Indicator.prototype = {
         this._fullMenuItems = [new PopupMenu.PopupSeparatorMenuItem(),
                                new PopupMenu.PopupMenuItem(_("Send Files to Device...")),
                                new PopupMenu.PopupMenuItem(_("Setup a New Device..."))];
+        this._hasDevices = false;
         this._deviceSep = this._fullMenuItems[0]; // hidden if no device exists
 
         this._fullMenuItems[1].connect('activate', function() {
@@ -118,22 +119,56 @@ Indicator.prototype = {
         }
     },
 
-    _updateDevices: function() {
-        this._destroyAll(this._deviceItems);
-        this._deviceItems = [];
+    _deviceCompare: function(d1, d2) {
+        return d1.device_path == d2.device_path &&
+            d1.bdaddr == d2.bdaddr &&
+            d1.can_connect == d2.can_connect &&
+            d1.capabilities == d2.capabilities;
+    },
 
+    _updateDevices: function() {
         let devices = this._applet.get_devices();
-        let anydevice = false;
+
+        for (let i = 0; i < this._deviceItems.length; i++) {
+            let item = this._deviceItems.length;
+            let destroy = true;
+            for (let j = 0; j < devices.length; j++) {
+                // we need to deep compare because BluetoothSimpleDevice is a boxed type
+                // (but we take advantage of that, because _skip will disappear the next
+                // time get_devices() is called)
+                if (this._deviceCompare(item._device, devices[i])) {
+                    item.label.text = devices[i].alias;
+                    devices[i]._skip = true;
+                    destroy = false;
+                }
+            }
+            if (destroy) {
+                item.destroy();
+                item._destroyed = true;
+            }
+        }
+
+        let newlist = [ ];
+        for (let i = 0; i < this._deviceItems.length; i++) {
+            let item = this._deviceItems[i];
+            if (!item._destroyed)
+                newlist.push(item);
+        }
+        this._deviceItems = newlist;
+
+        this._hasDevices = newlist.length > 0;
         for (let i = 0; i < devices.length; i++) {
             let d = devices[i];
+            if (d._skip)
+                continue;
             let item = this._createDeviceItem(d);
             if (item) {
                 this.menu.addMenuItem(item, this._deviceItemPosition + this._deviceItems.length);
                 this._deviceItems.push(item);
-                anydevice = true;
+                this._hasDevices = true;
             }
         }
-        if (anydevice)
+        if (this._hasDevices)
             this._deviceSep.actor.show();
         else
             this._deviceSep.actor.hide();