Revert 138216 - [Sync] Turn notifier::PushClient into an interface

jingle/notifier/listener/push_client.h

Index: jingle/notifier/listener/push_client.h
===================================================================
--- jingle/notifier/listener/push_client.h	(revision 138220)
+++ jingle/notifier/listener/push_client.h	(working copy)
@@ -6,44 +6,91 @@
 #define JINGLE_NOTIFIER_LISTENER_PUSH_CLIENT_H_
 
 #include <string>
+#include <vector>
 
-#include "base/memory/scoped_ptr.h"
+#include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "jingle/notifier/base/notifier_options.h"
 #include "jingle/notifier/listener/notification_defines.h"
 
+namespace base {
+class MessageLoopProxy;
+} // namespace base
+
+namespace buzz {
+class XmppTaskParentInterface;
+}  // namespace buzz
+
 namespace notifier {
 
-struct NotifierOptions;
-class PushClientObserver;
-
-// A PushClient is an interface for classes that implement a push
-// mechanism, where a client can push notifications to and receive
-// notifications from other clients.
+// This class implements a client for the XMPP google:push protocol.
+//
+// This class must be used on a single thread.
 class PushClient {
  public:
-  virtual ~PushClient();
+  // An Observer is sent messages whenever a notification is received
+  // or when the state of the push client changes.
+  class Observer {
+   public:
+    // Called when the state of the push client changes.  If
+    // |notifications_enabled| is true, that means notifications can
+    // be sent and received freely.  If it is false, that means no
+    // notifications can be sent or received.
+    virtual void OnNotificationStateChange(bool notifications_enabled) = 0;
 
-  // Creates a default non-blocking PushClient implementation from the
-  // given options.
-  static scoped_ptr<PushClient> CreateDefault(
-      const NotifierOptions& notifier_options);
+    // Called when a notification is received.  The details of the
+    // notification are in |notification|.
+    virtual void OnIncomingNotification(const Notification& notification) = 0;
 
-  // Manage the list of observers for incoming notifications.
-  virtual void AddObserver(PushClientObserver* observer) = 0;
-  virtual void RemoveObserver(PushClientObserver* observer) = 0;
+   protected:
+    virtual ~Observer();
+  };
 
-  // Implementors are required to have this take effect only on the
-  // next (re-)connection.  Therefore, clients should call this before
-  // UpdateCredentials().
-  virtual void UpdateSubscriptions(const SubscriptionList& subscriptions) = 0;
+  explicit PushClient(const NotifierOptions& notifier_options);
+  ~PushClient();
 
+  void AddObserver(Observer* observer);
+  void RemoveObserver(Observer* observer);
+
+  // Takes effect only on the next (re-)connection.  Therefore, you
+  // probably want to call this before UpdateCredentials().
+  void UpdateSubscriptions(const SubscriptionList& subscriptions);
+
   // If not connected, connects with the given credentials.  If
   // already connected, the next connection attempt will use the given
   // credentials.
-  virtual void UpdateCredentials(
-      const std::string& email, const std::string& token) = 0;
+  void UpdateCredentials(const std::string& email, const std::string& token);
 
-  // Sends a notification (with no reliability guarantees).
-  virtual void SendNotification(const Notification& notification) = 0;
+  // Sends a notification.  Can be called when notifications are
+  // disabled; the notification will be sent when notifications become
+  // enabled.
+  void SendNotification(const Notification& notification);
+
+  void SimulateOnNotificationReceivedForTest(
+      const Notification& notification);
+
+  void SimulateConnectAndSubscribeForTest(
+      base::WeakPtr<buzz::XmppTaskParentInterface> base_task);
+
+  void SimulateDisconnectForTest();
+
+  void SimulateSubscriptionErrorForTest();
+
+  // Any notifications sent after this is called will be reflected,
+  // i.e. will be treated as an incoming notification also.
+  void ReflectSentNotificationsForTest();
+
+ private:
+  class Core;
+
+  // The real guts of PushClient, which allows this class to not be
+  // refcounted.
+  const scoped_refptr<Core> core_;
+  const scoped_refptr<base::MessageLoopProxy> parent_message_loop_proxy_;
+  const scoped_refptr<base::MessageLoopProxy> io_message_loop_proxy_;
+
+  DISALLOW_COPY_AND_ASSIGN(PushClient);
 };
 
 }  // namespace notifier