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// Session manager of Mozc server.

#ifndef MOZC_SESSION_SESSION_HANDLER_H_
#define MOZC_SESSION_SESSION_HANDLER_H_

#include <map>
#include <string>
#include <utility>

#include "base/base.h"
#include "session/common.h"
#include "session/session_handler_interface.h"
#include "storage/lru_cache.h"

// for FRIEND_TEST()
#include "testing/base/public/gunit_prod.h"

namespace mozc {
class SessionWatchDog;
class Stopwatch;

namespace commands {
class Command;
}  // namespace commands

namespace session {
class SessionFactoryInterface;
class SessionInterface;
class SessionObserverHandler;
class SessionObserverInterface;
}  // namespace session

class SessionHandler : public SessionHandlerInterface {
 public:
  SessionHandler();
  virtual ~SessionHandler();

  // Returns true if SessionHandle is available.
  virtual bool IsAvailable() const;

  virtual bool EvalCommand(commands::Command *command);

  // Starts watch dog timer to cleanup sessions.
  virtual bool StartWatchDog();

  // NewSession returns new Sessoin.
  // Client needs to delete it properly
  session::SessionInterface *NewSession();

  virtual void AddObserver(session::SessionObserverInterface *observer);

  void SetSessionFactory(session::SessionFactoryInterface *new_factory);

 private:
  FRIEND_TEST(SessionHandlerTest, StorageTest);

  // Reload settings which are managed by SessionHandler
  void ReloadSession();
  // Reload the configurations on the current sessions.
  void ReloadConfig();

  bool CreateSession(commands::Command *command);
  bool DeleteSession(commands::Command *command);
  bool TestSendKey(commands::Command *command);
  bool SendKey(commands::Command *command);
  bool SendCommand(commands::Command *command);
  bool SyncData(commands::Command *command);
  bool ClearUserHistory(commands::Command *command);
  bool ClearUserPrediction(commands::Command *command);
  bool ClearUnusedUserPrediction(commands::Command *command);
  bool Shutdown(commands::Command *command);
  bool Reload(commands::Command *command);
  bool GetStoredConfig(commands::Command *command);
  bool SetStoredConfig(commands::Command *command);
  bool SetImposedConfig(commands::Command *command);
  bool Cleanup(commands::Command *command);
  bool NoOperation(commands::Command *command);

  SessionID CreateNewSessionID();
  bool DeleteSessionID(SessionID id);

  typedef LRUCache<SessionID, session::SessionInterface*> SessionMap;
  typedef LRUCache<SessionID,
                   session::SessionInterface*>::Element SessionElement;
  scoped_ptr<SessionMap> session_map_;
  scoped_ptr<SessionWatchDog> session_watch_dog_;
  bool is_available_;
  int keyevent_counter_;
  uint32 max_session_size_;
  uint64 last_session_empty_time_;
  uint64 last_cleanup_time_;
  uint64 last_create_session_time_;

  session::SessionFactoryInterface *session_factory_;
  scoped_ptr<session::SessionObserverHandler> observer_handler_;
  scoped_ptr<Stopwatch> stopwatch_;

  DISALLOW_COPY_AND_ASSIGN(SessionHandler);
};

}  // namespace mozc
#endif  // MOZC_SESSION_SESSION_HANDLER_H_