src/chrome/renderer/resources/extensions/automation/automation_node.js

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 var AutomationEvent = require('automationEvent').AutomationEvent;
   6 var automationInternal =
   7     require('binding').Binding.create('automationInternal').generate();
   8 var utils = require('utils');
   9
  10 /**
  11  * A single node in the Automation tree.
  12  * @param {AutomationTree} owner The owning tree.
  13  * @constructor
  14  */
  15 var AutomationNodeImpl = function(owner) {
  16   this.owner = owner;
  17   this.childIds = [];
  18   this.attributes = {};
  19   this.listeners = {};
  20   this.location = { left: 0, top: 0, width: 0, height: 0 };
  21 };
  22
  23 AutomationNodeImpl.prototype = {
  24   id: -1,
  25   role: '',
  26   loaded: false,
  27   state: { busy: true },
  28
  29   parent: function() {
  30     return this.owner.get(this.parentID);
  31   },
  32
  33   firstChild: function() {
  34     var node = this.owner.get(this.childIds[0]);
  35     return node;
  36   },
  37
  38   lastChild: function() {
  39     var childIds = this.childIds;
  40     var node = this.owner.get(childIds[childIds.length - 1]);
  41     return node;
  42   },
  43
  44   children: function() {
  45     var children = [];
  46     for (var i = 0, childID; childID = this.childIds[i]; i++)
  47       children.push(this.owner.get(childID));
  48     return children;
  49   },
  50
  51   previousSibling: function() {
  52     var parent = this.parent();
  53     if (parent && this.indexInParent > 0)
  54       return parent.children()[this.indexInParent - 1];
  55     return undefined;
  56   },
  57
  58   nextSibling: function() {
  59     var parent = this.parent();
  60     if (parent && this.indexInParent < parent.children().length)
  61       return parent.children()[this.indexInParent + 1];
  62     return undefined;
  63   },
  64
  65   doDefault: function() {
  66     this.performAction_('doDefault');
  67   },
  68
  69   focus: function() {
  70     this.performAction_('focus');
  71   },
  72
  73   makeVisible: function() {
  74     this.performAction_('makeVisible');
  75   },
  76
  77   setSelection: function(startIndex, endIndex) {
  78     this.performAction_('setSelection',
  79                         {startIndex: startIndex, endIndex: endIndex});
  80   },
  81
  82   addEventListener: function(eventType, callback, capture) {
  83     this.removeEventListener(eventType, callback);
  84     if (!this.listeners[eventType])
  85       this.listeners[eventType] = [];
  86     this.listeners[eventType].push({callback: callback, capture: capture});
  87   },
  88
  89   // TODO(dtseng/aboxhall): Check this impl against spec.
  90   removeEventListener: function(eventType, callback) {
  91     if (this.listeners[eventType]) {
  92       var listeners = this.listeners[eventType];
  93       for (var i = 0; i < listeners.length; i++) {
  94         if (callback === listeners[i].callback)
  95           listeners.splice(i, 1);
  96       }
  97     }
  98   },
  99
 100   dispatchEvent: function(eventType) {
 101     var path = [];
 102     var parent = this.parent();
 103     while (parent) {
 104       path.push(parent);
 105       // TODO(aboxhall/dtseng): handle unloaded parent node
 106       parent = parent.parent();
 107     }
 108     path.push(this.owner.wrapper);
 109     var event = new AutomationEvent(eventType, this.wrapper);
 110
 111     // Dispatch the event through the propagation path in three phases:
 112     // - capturing: starting from the root and going down to the target's parent
 113     // - targeting: dispatching the event on the target itself
 114     // - bubbling: starting from the target's parent, going back up to the root.
 115     // At any stage, a listener may call stopPropagation() on the event, which
 116     // will immediately stop event propagation through this path.
 117     if (this.dispatchEventAtCapturing_(event, path)) {
 118       if (this.dispatchEventAtTargeting_(event, path))
 119         this.dispatchEventAtBubbling_(event, path);
 120     }
 121   },
 122
 123   toString: function() {
 124     return 'node id=' + this.id +
 125         ' role=' + this.role +
 126         ' state=' + JSON.stringify(this.state) +
 127         ' childIds=' + JSON.stringify(this.childIds) +
 128         ' attributes=' + JSON.stringify(this.attributes);
 129   },
 130
 131   dispatchEventAtCapturing_: function(event, path) {
 132     privates(event).impl.eventPhase = Event.CAPTURING_PHASE;
 133     for (var i = path.length - 1; i >= 0; i--) {
 134       this.fireEventListeners_(path[i], event);
 135       if (privates(event).impl.propagationStopped)
 136         return false;
 137     }
 138     return true;
 139   },
 140
 141   dispatchEventAtTargeting_: function(event) {
 142     privates(event).impl.eventPhase = Event.AT_TARGET;
 143     this.fireEventListeners_(this.wrapper, event);
 144     return !privates(event).impl.propagationStopped;
 145   },
 146
 147   dispatchEventAtBubbling_: function(event, path) {
 148     privates(event).impl.eventPhase = Event.BUBBLING_PHASE;
 149     for (var i = 0; i < path.length; i++) {
 150       this.fireEventListeners_(path[i], event);
 151       if (privates(event).impl.propagationStopped)
 152         return false;
 153     }
 154     return true;
 155   },
 156
 157   fireEventListeners_: function(node, event) {
 158     var nodeImpl = privates(node).impl;
 159     var listeners = nodeImpl.listeners[event.type];
 160     if (!listeners)
 161       return;
 162
 163     var eventPhase = event.eventPhase;
 164     for (var i = 0; i < listeners.length; i++) {
 165       if (eventPhase == Event.CAPTURING_PHASE && !listeners[i].capture)
 166         continue;
 167       if (eventPhase == Event.BUBBLING_PHASE && listeners[i].capture)
 168         continue;
 169
 170       try {
 171         listeners[i].callback(event);
 172       } catch (e) {
 173         console.error('Error in event handler for ' + event.type +
 174                       'during phase ' + eventPhase + ': ' +
 175                       e.message + '\nStack trace: ' + e.stack);
 176       }
 177     }
 178   },
 179
 180   performAction_: function(actionType, opt_args) {
 181     // Not yet initialized.
 182     if (!this.owner.processID ||
 183         !this.owner.routingID ||
 184         !this.wrapper.id)
 185       return;
 186     automationInternal.performAction({processID: this.owner.processID,
 187                                       routingID: this.owner.routingID,
 188                                       automationNodeID: this.wrapper.id,
 189                                       actionType: actionType},
 190                                      opt_args || {});
 191   }
 192 };
 193
 194 var AutomationNode = utils.expose('AutomationNode',
 195                                   AutomationNodeImpl,
 196                                   { functions: ['parent',
 197                                                 'firstChild',
 198                                                 'lastChild',
 199                                                 'children',
 200                                                 'previousSibling',
 201                                                 'nextSibling',
 202                                                 'doDefault',
 203                                                 'focus',
 204                                                 'makeVisible',
 205                                                 'setSelection',
 206                                                 'addEventListener',
 207                                                 'removeEventListener'],
 208                                     readonly: ['id',
 209                                                'role',
 210                                                'state',
 211                                                'location',
 212                                                'attributes',
 213                                                'loaded'] });
 214
 215 exports.AutomationNode = AutomationNode;