bluetooth: Componentize device list in chrome://bluetooth-internals.

chrome/browser/resources/bluetooth_internals/device_collection.js

+// Copyright 2016 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.
+
+/**
+ * Javascript for Device-related features, served from
+ *     chrome://bluetooth-internals/.
+ */
+
+cr.define('device_collection', function() {
+  /*
+   * Collection of devices.
+   * @constructor
+   * @param {!Array} array the starting collection of devices.
+   * @extends {cr.ui.ArrayDataModel}
+   */
+  var DeviceCollection = function(array) {
+    cr.ui.ArrayDataModel.call(this, array);
+  };
+  DeviceCollection.prototype = {
+    __proto__: cr.ui.ArrayDataModel.prototype,
+    /**
+     * Finds the Device in the collection with the matching address.
+     * @param {!string} address
+     */
+    getByAddress: function(address) {
+      for (var i = 0; i < this.length; i++) {
+        var device = this.item(i);
+        if (address == device.info.address)
+          return device;
+      }
+      return null;
+    },
+    /**
+     * Adds or updates a Device with new DeviceInfo.
+     * @param {!interfaces.BluetoothDevice.DeviceInfo} deviceInfo
+     */
+    addOrUpdate: function(deviceInfo) {
+      var oldDevice = this.getByAddress(deviceInfo.address);
+      if (oldDevice) {
+        // Update rssi if it's valid
+        var rssi = (deviceInfo.rssi && deviceInfo.rssi.value) ||
+            (oldDevice.info.rssi && oldDevice.info.rssi.value);
+
+        oldDevice.info = deviceInfo;
+        oldDevice.info.rssi = { value: rssi };
+        oldDevice.removed = false;
+
+        this.updateIndex(this.indexOf(oldDevice));
+      } else {
+        var device = new Device(deviceInfo);
+        this.push(device);
+      }
+    },
+    remove: function(deviceInfo) {
+      var device = this.getByAddress(deviceInfo.address);
+      assert(device,
+             'Device does not exist.');
+      device.removed = true;
+    }
+  };
+
+  /*
+   * Data model for a cached device.
+   * @constructor
+   * @param {!interfaces.BluetoothDevice.DeviceInfo} info
+   */
+  var Device = function(info) {
+    this.info = info;
+    this.removed = false;
+  };
+
+  return {
+    DeviceCollection, DeviceCollection,
+  };
+});