Implement chrome.experimental.downloads.onChanged

chrome/browser/extensions/extension_downloads_api.h

 // Copyright (c) 2011 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 CHROME_BROWSER_EXTENSIONS_EXTENSION_DOWNLOADS_API_H_
 #define CHROME_BROWSER_EXTENSIONS_EXTENSION_DOWNLOADS_API_H_
 #pragma once
 
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/file_path.h"
 #include "base/memory/singleton.h"
+#include "base/stl_util.h"
 #include "base/string16.h"
 #include "chrome/browser/extensions/extension_function.h"
 #include "content/browser/download/download_item.h"
 #include "content/browser/download/download_manager.h"
 
 namespace base {
 class DictionaryValue;
 }
 class ResourceDispatcherHost;
 class TabContents;
@@ skipping 223 matching lines @@
   DECLARE_EXTENSION_FUNCTION_NAME("experimental.downloads.drag");
 
  protected:
   virtual bool ParseArgs() OVERRIDE;
   virtual void RunInternal() OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DownloadsDragFunction);
 };
 
-class ExtensionDownloadsEventRouter : public DownloadManager::Observer {
+// Observes a single DownloadManager and many DownloadItems and dispatches
+// onCreated and onErased events.
+class ExtensionDownloadsEventRouter : public DownloadManager::Observer,
+                                      public DownloadItem::Observer {
  public:
   explicit ExtensionDownloadsEventRouter(Profile* profile);
   virtual ~ExtensionDownloadsEventRouter();
 
   virtual void ModelChanged() OVERRIDE;
   virtual void ManagerGoingDown() OVERRIDE;
+  virtual void OnDownloadUpdated(DownloadItem* download) OVERRIDE;
+  virtual void OnDownloadOpened(DownloadItem* download) OVERRIDE;
 
  private:
+  struct OnChangedStat {
+    OnChangedStat();
+    ~OnChangedStat();
+    int fires;
+    int total;
+  };
+
+  typedef std::map<int, DownloadItem*> ItemMap;
+  typedef std::map<int, base::DictionaryValue*> ItemJsonMap;
+  typedef std::map<int, OnChangedStat*> OnChangedStatMap;
+
   void DispatchEvent(const char* event_name, base::Value* json_arg);
-  typedef base::hash_map<int, DownloadItem*> ItemMap;
-  typedef std::set<int> DownloadIdSet;
 
   Profile* profile_;
   DownloadManager* manager_;
-  DownloadIdSet downloads_;
+  ItemMap downloads_;
+  ItemJsonMap item_jsons_;
+  STLValueDeleter<ItemJsonMap> delete_item_jsons_;
+  OnChangedStatMap on_changed_stats_;
+  STLValueDeleter<OnChangedStatMap> delete_on_changed_stats_;
 
   DISALLOW_COPY_AND_ASSIGN(ExtensionDownloadsEventRouter);
 };
 #endif  // CHROME_BROWSER_EXTENSIONS_EXTENSION_DOWNLOADS_API_H_