Browser Plugin: Implement CanGoBack/CanGoForward

content/renderer/browser_plugin/browser_plugin.cc

 // Copyright (c) 2012 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.
 
 #include "content/renderer/browser_plugin/browser_plugin.h"
 
 #include "base/message_loop.h"
 #include "base/string_util.h"
 #if defined (OS_WIN)
 #include "base/sys_info.h"
@@ skipping 54 matching lines @@
     : instance_id_(instance_id),
       render_view_(render_view),
       container_(NULL),
       damage_buffer_(NULL),
       sad_guest_(NULL),
       guest_crashed_(false),
       resize_pending_(false),
       navigate_src_sent_(false),
       process_id_(-1),
       persist_storage_(false),
-      visible_(true) {
+      visible_(true),
+      current_nav_entry_index_(0),
+      nav_entry_count_(0) {
   BrowserPluginManager::Get()->AddBrowserPlugin(instance_id, this);
   bindings_.reset(new BrowserPluginBindings(this));
 
   ParseAttributes(params);
 }
 
 BrowserPlugin::~BrowserPlugin() {
   if (damage_buffer_)
     FreeDamageBuffer();
   RemoveEventListeners();
@@ skipping 56 matching lines @@
 
 std::string BrowserPlugin::GetPartitionAttribute() const {
   std::string value;
   if (persist_storage_)
     value.append(kPersistPrefix);
 
   value.append(storage_partition_id_);
   return value;
 }
 
+bool BrowserPlugin::CanGoBack() const {
+  return nav_entry_count_ > 1 && current_nav_entry_index_ > 0;
+}
+
+bool BrowserPlugin::CanGoForward() const {
+  return current_nav_entry_index_ >= 0 &&
+      current_nav_entry_index_ < (nav_entry_count_ - 1);
+}
+
 bool BrowserPlugin::SetPartitionAttribute(const std::string& partition_id,
                                           std::string& error_message) {
   if (navigate_src_sent_) {
     error_message =
       "The object has already navigated, so its partition cannot be changed.";
     return false;
   }
 
   std::string input = partition_id;
 
@@ skipping 172 matching lines @@
   // called. See http://crbug.com/155044.
   EventListeners listeners(event_listener_map_[kCrashEventName]);
   EventListeners::iterator it = listeners.begin();
   for (; it != listeners.end(); ++it) {
     WebKit::WebFrame* frame = plugin.document().frame();
     if (frame)
       frame->callFunctionEvenIfScriptDisabled(*it, v8::Object::New(), 0, NULL);
   }
 }
 
-void BrowserPlugin::DidNavigate(const GURL& url, int process_id) {
-  src_ = url.spec();
-  process_id_ = process_id;
+void BrowserPlugin::DidNavigate(
+    const BrowserPluginMsg_DidNavigate_Params& params) {
+  src_ = params.url.spec();
+  process_id_ = params.process_id;
+  current_nav_entry_index_ = params.current_entry_index;
+  nav_entry_count_ = params.entry_count;
+
   if (!HasListeners(kNavigationEventName))
     return;
 
   WebKit::WebElement plugin = container()->element();
   v8::HandleScope handle_scope;
   v8::Context::Scope context_scope(
       plugin.document().frame()->mainWorldScriptContext());
 
-  v8::Local<v8::Value> param = v8::String::New(src_.data(), src_.size());
+  // Construct the navigation event object.
+  v8::Local<v8::Object> event = v8::Object::New();
+  event->Set(v8::String::New(kURL, sizeof(kURL) - 1),
+             v8::String::New(src_.data(), src_.size()));
+  event->Set(v8::String::New(kIsTopLevel, sizeof(kIsTopLevel) - 1),
+             v8::Boolean::New(params.is_top_level));
+  v8::Local<v8::Value> val = event;
 
   // TODO(fsamuel): Copying the event listeners is insufficent because
   // new persistent handles are not created when the copy constructor is
   // called. See http://crbug.com/155044.
   EventListeners listeners(event_listener_map_[kNavigationEventName]);
   EventListeners::iterator it = listeners.begin();
   for (; it != listeners.end(); ++it) {
     WebKit::WebFrame* frame = plugin.document().frame();
     if (frame) {
       frame->callFunctionEvenIfScriptDisabled(
-          *it, v8::Object::New(), 1, &param);
+          *it, v8::Object::New(), 1, &val);
     }
   }
 }
 
 void BrowserPlugin::LoadStart(const GURL& url, bool is_top_level) {
   if (!HasListeners(kLoadStartEventName))
     return;
 
   WebKit::WebElement plugin = container()->element();
   v8::HandleScope handle_scope;
@@ skipping 373 matching lines @@
                                                  void* notify_data) {
 }
 
 void BrowserPlugin::didFailLoadingFrameRequest(
     const WebKit::WebURL& url,
     void* notify_data,
     const WebKit::WebURLError& error) {
 }
 
 }  // namespace content