Revert 46567 - Reimplement accessibility of web content by caching the entire...

webkit/glue/webaccessibility.h

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2006-2008 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.
 
 #ifndef WEBKIT_GLUE_WEBACCESSIBILITY_H_
 #define WEBKIT_GLUE_WEBACCESSIBILITY_H_
 
-#include <vector>
-
 #include "base/string16.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebAccessibilityObject.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebAccessibilityRole.h"
-#include "third_party/WebKit/WebKit/chromium/public/WebRect.h"
 
 namespace WebKit {
 class WebAccessibilityCache;
 }
 
 namespace webkit_glue {
 
-// A compact representation of the accessibility information for a
-// single web object, in a form that can be serialized and sent from
-// the renderer process to the browser process.
-struct WebAccessibility {
+class WebAccessibility {
  public:
-  // An alphabetical enumeration of accessibility roles.
+  // This defines an enumeration of IDs that can uniquely identify a call to a
+  // specific accessibility information function. Should match the support
+  // implemented in WebKit and GlueAccessibilityObject (functions marked with
+  // return value E_NOTIMPL in WebKit are also excluded).
+  enum Function {
+    FUNCTION_NONE = 0,
+
+    // Supported accessibility information retrieval functions.
+    FUNCTION_DODEFAULTACTION,
+    FUNCTION_HITTEST,
+    FUNCTION_LOCATION,
+    FUNCTION_NAVIGATE,
+    FUNCTION_GETCHILD,
+    FUNCTION_CHILDCOUNT,
+    FUNCTION_DEFAULTACTION,
+    FUNCTION_DESCRIPTION,
+    FUNCTION_GETFOCUSEDCHILD,
+    FUNCTION_HELPTEXT,
+    FUNCTION_KEYBOARDSHORTCUT,
+    FUNCTION_NAME,
+    FUNCTION_GETPARENT,
+    FUNCTION_ROLE,
+    FUNCTION_STATE,
+    FUNCTION_VALUE
+
+    // The deprecated put_accName and put_accValue (IAccessible) are not
+    // supported here, nor is accSelect, get_accHelpTopic and get_accSelection
+    // (matching WebKit's support for IAccessible).
+  };
+
+  // This defines an enumeration of navigation directions based on (but
+  // independent of) the MSAA Navigation Constants. However, to avoid the use of
+  // COM in our Glue layer, we use this as a substitute with a one-to-one
+  // conversion between Browser side (has COM) and Glue.
+  enum Direction {
+    DIRECTION_NONE = 0,
+
+    // Valid directions.
+    DIRECTION_UP,
+    DIRECTION_DOWN,
+    DIRECTION_LEFT,
+    DIRECTION_RIGHT,
+    DIRECTION_NEXT,
+    DIRECTION_PREVIOUS,
+    DIRECTION_FIRSTCHILD,
+    DIRECTION_LASTCHILD
+  };
+
+  // This defines an enumeration (in alphabetical order) of the supported
+  // accessibility roles in our Glue layer (used in
+  // GlueAccessibilityObject::Role). Any interface using roles must provide a
+  // conversion to its own roles (see e.g. BrowserAccessibility::get_accRole and
+  // BrowserAccessibility::MSAARole).
   enum Role {
-    ROLE_NONE = 0,
-
     ROLE_APPLICATION,
     ROLE_CELL,
     ROLE_CHECKBUTTON,
     ROLE_CLIENT,
     ROLE_COLUMN,
     ROLE_COLUMNHEADER,
     ROLE_DOCUMENT,
     ROLE_GRAPHIC,
     ROLE_GROUPING,
     ROLE_LINK,
@@ skipping 10 matching lines @@
     ROLE_RADIOBUTTON,
     ROLE_ROW,
     ROLE_ROWHEADER,
     ROLE_SEPARATOR,
     ROLE_SLIDER,
     ROLE_STATICTEXT,
     ROLE_STATUSBAR,
     ROLE_TABLE,
     ROLE_TEXT,
     ROLE_TOOLBAR,
-    ROLE_TOOLTIP,
-    NUM_ROLES
+    ROLE_TOOLTIP
   };
 
-  // An alphabetical enumeration of accessibility states.
-  // A state bitmask is formed by shifting 1 to the left by each state,
-  // for example:
-  //   int mask = (1 << STATE_CHECKED) | (1 << STATE_FOCUSED);
+  // This defines an enumeration (in alphabetical order) of the supported
+  // accessibility states in our Glue layer (used in
+  // GlueAccessibilityObject::State). Any interface using states must provide a
+  // conversion to its own states (see e.g. BrowserAccessibility::get_accState
+  // and BrowserAccessibility::MSAAState).
   enum State {
     STATE_CHECKED,
     STATE_FOCUSABLE,
     STATE_FOCUSED,
     STATE_HOTTRACKED,
     STATE_INDETERMINATE,
     STATE_LINKED,
     STATE_MULTISELECTABLE,
     STATE_OFFSCREEN,
     STATE_PRESSED,
     STATE_PROTECTED,
     STATE_READONLY,
     STATE_TRAVERSED,
     STATE_UNAVAILABLE
   };
 
-  // Empty constructor, for serialization.
-  WebAccessibility();
+  enum ReturnCode {
+    RETURNCODE_TRUE,    // MSAA S_OK
+    RETURNCODE_FALSE,   // MSAA S_FALSE
+    RETURNCODE_FAIL     // E_FAIL
+  };
 
-  // Construct from a WebAccessibilityObject. Recursively creates child
-  // nodes as needed to complete the tree. Adds |src| to |cache| and
-  // stores its cache ID.
-  WebAccessibility(const WebKit::WebAccessibilityObject& src,
-                   WebKit::WebAccessibilityCache* cache);
+  // Parameters structure to hold a union of the possible accessibility function
+  // INPUT variables, with the unused fields always set to default value. Used
+  // in ViewMsg_GetAccessibilityInfo, as only parameter.
+  struct InParams {
+    // Identifier to uniquely distinguish which instance of accessibility
+    // information is being called upon on the renderer side.
+    int object_id;
 
-  // Initialize an already-created struct, same as the constructor a
-  void Init(const WebKit::WebAccessibilityObject& src,
-            WebKit::WebAccessibilityCache* cache);
+    // Identifier to resolve which accessibility information retrieval function
+    // is being called.
+    int function_id;
 
-  // This is a simple serializable struct. All member variables should be
-  // copyable.
-  int32 id;
-  string16 name;
-  string16 value;
-  string16 action;
-  string16 description;
-  string16 help;
-  string16 shortcut;
-  Role role;
-  uint32 state;
-  WebKit::WebRect location;
-  std::vector<WebAccessibility> children;
+    // Id of accessible child, whose information is being requested.
+    int child_id;
+
+    // LONG input parameters, used differently depending on the function called.
+    long input_long1;
+    long input_long2;
+  };
+
+  // Parameters structure to hold a union of the possible accessibility function
+  // OUTPUT variables, with the unused fields always set to default value. Used
+  // in ViewHostMsg_GetAccessibilityInfoResponse, as only parameter.
+  struct OutParams {
+    // Identifier to uniquely distinguish which instance of accessibility
+    // information is being called upon on the renderer side.
+    int object_id;
+
+    // LONG output parameters, used differently depending on the function
+    // called. [output_long1] can in some cases be set to -1 to indicate that
+    // the child object found by the called IAccessible function is not a simple
+    // object.
+    long output_long1;
+    long output_long2;
+    long output_long3;
+    long output_long4;
+
+    // String output parameter.
+    string16 output_string;
+
+    // Return code of the accessibility function call.
+    int32 return_code;
+  };
+
+  static int32 GetAccObjInfo(WebKit::WebAccessibilityCache* cache,
+      const InParams& in_params, OutParams* out_params);
 };
 
 }  // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_WEBACCESSIBILITY_H_