sync/js/sync_js_controller.h

   1 // Copyright 2012 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 #ifndef SYNC_JS_SYNC_JS_CONTROLLER_H_
   6 #define SYNC_JS_SYNC_JS_CONTROLLER_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "base/observer_list.h"
  15 #include "sync/base/sync_export.h"
  16 #include "sync/internal_api/public/util/weak_handle.h"
  17 #include "sync/js/js_controller.h"
  18 #include "sync/js/js_event_handler.h"
  19
  20 namespace syncer {
  21
  22 class JsBackend;
  23
  24 // A class that mediates between the sync JsEventHandlers and the sync
  25 // JsBackend.
  26 class SYNC_EXPORT SyncJsController
  27     : public JsController, public JsEventHandler,
  28       public base::SupportsWeakPtr<SyncJsController> {
  29  public:
  30   SyncJsController();
  31
  32   ~SyncJsController() override;
  33
  34   // Sets the backend to route all messages to (if initialized).
  35   // Sends any queued-up messages if |backend| is initialized.
  36   void AttachJsBackend(const WeakHandle<JsBackend>& js_backend);
  37
  38   // JsController implementation.
  39   void AddJsEventHandler(JsEventHandler* event_handler) override;
  40   void RemoveJsEventHandler(JsEventHandler* event_handler) override;
  41
  42   // JsEventHandler implementation.
  43   void HandleJsEvent(const std::string& name,
  44                      const JsEventDetails& details) override;
  45
  46  private:
  47   // Sets |js_backend_|'s event handler depending on how many
  48   // underlying event handlers we have.
  49   void UpdateBackendEventHandler();
  50
  51   WeakHandle<JsBackend> js_backend_;
  52   base::ObserverList<JsEventHandler> js_event_handlers_;
  53
  54   DISALLOW_COPY_AND_ASSIGN(SyncJsController);
  55 };
  56
  57 }  // namespace syncer
  58
  59 #endif  // SYNC_JS_SYNC_JS_CONTROLLER_H_