Implement automatic load of composed/embedded automation trees

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

 // Copyright 2014 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.
 
 var AutomationEvent = require('automationEvent').AutomationEvent;
 var automationInternal =
     require('binding').Binding.create('automationInternal').generate();
 var IsInteractPermitted =
     requireNative('automationInternal').IsInteractPermitted;
 
 var lastError = require('lastError');
 var logging = requireNative('logging');
 var schema = requireNative('automationInternal').GetSchemaAdditions();
 var utils = require('utils');
 
 /**
+ * Maps an accessibility tree id to an AutomationNode with role type webView.
+ * @type {!Object.<string, string>}
+ */
+var idToWebView_ = {};
+
+/**
  * A single node in the Automation tree.
  * @param {AutomationRootNodeImpl} root The root of the tree.
  * @constructor
  */
 function AutomationNodeImpl(root) {
   this.rootImpl = root;
   this.childIds = [];
   // Public attributes. No actual data gets set on this object.
   this.attributes = {};
   // Internal object holding all attributes.
   this.attributesInternal = {};
   this.listeners = {};
   this.location = { left: 0, top: 0, width: 0, height: 0 };
 }
 
 AutomationNodeImpl.prototype = {
   id: -1,
   role: '',
   state: { busy: true },
   isRootNode: false,
 
   get root() {
     return this.rootImpl.wrapper;
   },
 
   parent: function() {
+    if (this.role == schema.RoleType.rootWebArea) {
+      if (idToWebView_[this.treeID])
+        return idToWebView_[this.treeID];
+    }
     return this.rootImpl.get(this.parentID);
   },
 
   firstChild: function() {
-    var node = this.rootImpl.get(this.childIds[0]);
-    return node;
+    return this.lookupWebViewChild_() || this.rootImpl.get(this.childIds[0]);
   },
 
   lastChild: function() {
     var childIds = this.childIds;
-    var node = this.rootImpl.get(childIds[childIds.length - 1]);
-    return node;
+    return this.lookupWebViewChild_() ||
+        this.rootImpl.get(childIds[childIds.length - 1]);
   },
 
   children: function() {
     var children = [];
     for (var i = 0, childID; childID = this.childIds[i]; i++) {
       logging.CHECK(this.rootImpl.get(childID));
       children.push(this.rootImpl.get(childID));
     }
     return children;
   },
@@ skipping 46 matching lines @@
           listeners.splice(i, 1);
       }
     }
   },
 
   dispatchEvent: function(eventType) {
     var path = [];
     var parent = this.parent();
     while (parent) {
       path.push(parent);
-      // TODO(aboxhall/dtseng): handle unloaded parent node
       parent = parent.parent();
     }
     var event = new AutomationEvent(eventType, this.wrapper);
 
     // Dispatch the event through the propagation path in three phases:
     // - capturing: starting from the root and going down to the target's parent
     // - targeting: dispatching the event on the target itself
     // - bubbling: starting from the target's parent, going back up to the root.
     // At any stage, a listener may call stopPropagation() on the event, which
     // will immediately stop event propagation through this path.
     if (this.dispatchEventAtCapturing_(event, path)) {
       if (this.dispatchEventAtTargeting_(event, path))
         this.dispatchEventAtBubbling_(event, path);
     }
   },
 
   toString: function() {
     return 'node id=' + this.id +
         ' role=' + this.role +
         ' state=' + $JSON.stringify(this.state) +
         ' parentID=' + this.parentID +
         ' childIds=' + $JSON.stringify(this.childIds) +
         ' attributes=' + $JSON.stringify(this.attributes);
   },
 
+  lookupWebViewChild_: function() {
+    if (this.role != schema.RoleType.webView)
+      return null;
+
+    return automationUtil.idToAutomationRootNode[this.childTreeID];
+  },
+
   dispatchEventAtCapturing_: function(event, path) {
     privates(event).impl.eventPhase = Event.CAPTURING_PHASE;
     for (var i = path.length - 1; i >= 0; i--) {
       this.fireEventListeners_(path[i], event);
       if (privates(event).impl.propagationStopped)
         return false;
     }
     return true;
   },
 
@@ skipping 30 matching lines @@
       } catch (e) {
         console.error('Error in event handler for ' + event.type +
                       'during phase ' + eventPhase + ': ' +
                       e.message + '\nStack trace: ' + e.stack);
       }
     }
   },
 
   performAction_: function(actionType, opt_args) {
     // Not yet initialized.
-    if (this.rootImpl.processID === undefined ||
-        this.rootImpl.routingID === undefined ||
+    if (this.rootImpl.treeID === undefined ||
         this.id === undefined) {
       return;
     }
 
     // Check permissions.
     if (!IsInteractPermitted()) {
       throw new Error(actionType + ' requires {"desktop": true} or' +
           ' {"interact": true} in the "automation" manifest key.');
     }
 
-    automationInternal.performAction({ processID: this.rootImpl.processID,
-                                       routingID: this.rootImpl.routingID,
+    automationInternal.performAction({ treeID: this.rootImpl.treeID,
                                        automationNodeID: this.id,
                                        actionType: actionType },
                                      opt_args || {});
   }
 };
 
 // Maps an attribute to its default value in an invalidated node.
 // These attributes are taken directly from the Automation idl.
 var AutomationAttributeDefaults = {
   'id': -1,
@@ skipping 27 matching lines @@
   'aria-labelledby': 'labelledbyIds',
   'aria-owns': 'ownsIds'
 };
 
 /**
  * A set of attributes ignored in the automation API.
  * @param {!Object.<string, boolean>}
  * @const
  */
 var ATTRIBUTE_BLACKLIST = {'activedescendantId': true,
+                           'childTreeId': true,
                            'controlsIds': true,
                            'describedbyIds': true,
                            'flowtoIds': true,
                            'labelledbyIds': true,
                            'ownsIds': true
 };
 
 
 /**
  * AutomationRootNode.
  *
  * An AutomationRootNode is the javascript end of an AXTree living in the
  * browser. AutomationRootNode handles unserializing incremental updates from
  * the source AXTree. Each update contains node data that form a complete tree
  * after applying the update.
  *
  * A brief note about ids used through this class. The source AXTree assigns
  * unique ids per node and we use these ids to build a hash to the actual
  * AutomationNode object.
  * Thus, tree traversals amount to a lookup in our hash.
  *
- * The tree itself is identified by the process id and routing id of the
+ * The tree itself is identified by the accessibility tree id of the
  * renderer widget host.
  * @constructor
  */
-function AutomationRootNodeImpl(processID, routingID) {
+function AutomationRootNodeImpl(treeID) {
   AutomationNodeImpl.call(this, this);
-  this.processID = processID;
-  this.routingID = routingID;
+  this.treeID = treeID;
   this.axNodeDataCache_ = {};
 }
 
 AutomationRootNodeImpl.prototype = {
   __proto__: AutomationNodeImpl.prototype,
 
   isRootNode: true,
 
+  role: 'rootWebArea',
+
   get: function(id) {
     if (id == undefined)
       return undefined;
 
     return this.axNodeDataCache_[id];
   },
 
   unserialize: function(update) {
     var updateState = { pendingNodes: {}, newNodes: {} };
     var oldRootId = this.id;
@@ skipping 41 matching lines @@
                     null,
                     chrome);
       return false;
     }
     return true;
   },
 
   destroy: function() {
     this.dispatchEvent(schema.EventType.destroyed);
     this.invalidate_(this.wrapper);
+    idToWebView_[this.treeID] = undefined;
   },
 
   onAccessibilityEvent: function(eventParams) {
     if (!this.unserialize(eventParams.update)) {
       logging.WARNING('unserialization failed');
       return false;
     }
 
     var targetNode = this.get(eventParams.targetID);
     if (targetNode) {
@@ skipping 33 matching lines @@
 
     // Retrieve the internal AutomationNodeImpl instance for this node.
     // This object is not accessible outside of bindings code, but we can access
     // it here.
     var nodeImpl = privates(node).impl;
     var id = nodeImpl.id;
     for (var key in AutomationAttributeDefaults) {
       nodeImpl[key] = AutomationAttributeDefaults[key];
     }
     nodeImpl.childIds = [];
-    nodeImpl.loaded = false;
     nodeImpl.id = id;
     delete this.axNodeDataCache_[id];
   },
 
-  load: function(callback) {
-    // TODO(dtseng/aboxhall): Implement.
-    if (!this.loaded)
-      throw 'Unsupported state: root node is not loaded.';
-
-    setTimeout(callback, 0);
-  },
-
   deleteOldChildren_: function(node, newChildIds) {
     // Create a set of child ids in |src| for fast lookup, and return false
     // if a duplicate is found;
     var newChildIdSet = {};
     for (var i = 0; i < newChildIds.length; i++) {
       var childId = newChildIds[i];
       if (newChildIdSet[childId]) {
         logging.WARNING('Node ' + privates(node).impl.id +
                         ' has duplicate child id ' + childId);
         lastError.set('automation',
@@ skipping 18 matching lines @@
       }
     }
     nodeImpl.childIds = oldChildIds;
 
     return true;
   },
 
   createNewChildren_: function(node, newChildIds, updateState) {
     logging.CHECK(node);
     var success = true;
+
     for (var i = 0; i < newChildIds.length; i++) {
       var childId = newChildIds[i];
       var childNode = this.axNodeDataCache_[childId];
       if (childNode) {
         if (childNode.parent() != node) {
           var parentId = -1;
           if (childNode.parent()) {
             var parentImpl = privates(childNode.parent()).impl;
             parentId = parentImpl.id;
           }
@@ skipping 18 matching lines @@
       }
       privates(childNode).impl.indexInParent = i;
       privates(childNode).impl.parentID = privates(node).impl.id;
     }
 
     return success;
   },
 
   setData_: function(node, nodeData) {
     var nodeImpl = privates(node).impl;
+
+    if (nodeData.role == schema.RoleType.webView) {
+      if (nodeImpl.pendingChildFrame === undefined)
+        nodeImpl.pendingChildFrame = true;
+
+      if (nodeImpl.pendingChildFrame) {
+        nodeImpl.childTreeID = nodeData.intAttributes.childTreeId;
+        idToWebView_[nodeImpl.childTreeID] = node;
+        automationInternal.enableFrame(nodeImpl.childTreeID);
+        automationUtil.storeTreeCallback(nodeImpl.childTreeID, function(root) {
+          nodeImpl.pendingChildFrame = false;
+          nodeImpl.dispatchEvent(schema.EventType.childrenChanged);
+        });
+      }
+    }
     for (var key in AutomationAttributeDefaults) {
       if (key in nodeData)
         nodeImpl[key] = nodeData[key];
       else
         nodeImpl[key] = AutomationAttributeDefaults[key];
     }
     for (var i = 0; i < AutomationAttributeTypes.length; i++) {
       var attributeType = AutomationAttributeTypes[i];
       for (var attributeName in nodeData[attributeType]) {
         nodeImpl.attributesInternal[attributeName] =
@@ skipping 94 matching lines @@
                                                 'removeEventListener'],
                                     readonly: ['isRootNode',
                                                'role',
                                                'state',
                                                'location',
                                                'attributes',
                                                'root'] });
 
 var AutomationRootNode = utils.expose('AutomationRootNode',
                                       AutomationRootNodeImpl,
-                                      { superclass: AutomationNode,
-                                        functions: ['load'],
-                                        readonly: ['loaded'] });
+                                      { superclass: AutomationNode });
 
 exports.AutomationNode = AutomationNode;
 exports.AutomationRootNode = AutomationRootNode;