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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 "storage/lru_cache.h"

namespace mozc {
class SessionWatchDog;
class Stopwatch;
namespace commands {
class Command;
}
namespace keymap {
class KeyMapManager;
}
namespace composer {
class Table;
}

namespace session {
class SessionObserverHandler;
class SessionObserverInterface;
}

class Session;
class ConverterInterface;

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

  // return true if SessionHandle is available
  bool IsAvailable() const;

  bool EvalCommand(commands::Command *command);

  // start watch dog timer to cleanup sessions
  bool StartWatchDog();

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

  void AddObserver(session::SessionObserverInterface *observer);

 private:
  // Reload settings which are managed by SessionHandler
  void ReloadSession();

  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 GetConfig(commands::Command *command);
  bool SetConfig(commands::Command *command);
  bool Cleanup(commands::Command *command);
  bool NoOperation(commands::Command *command);

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

  scoped_ptr<composer::Table> preedit_table_;
  typedef LRUCache<SessionID, Session*> SessionMap;
  typedef LRUCache<SessionID, Session*>::Element SessionElement;
  scoped_ptr<SessionMap> session_map_;
  scoped_ptr<keymap::KeyMapManager> keymap_;
  scoped_ptr<SessionWatchDog> session_watch_dog_;
  ConverterInterface *converter_;
  bool is_available_;
  int keyevent_counter_;
  uint32 max_session_size_;
  uint64 last_session_empty_time_;
  uint64 last_cleanup_time_;
  uint64 last_create_session_time_;

  scoped_ptr<session::SessionObserverHandler> observer_handler_;
  scoped_ptr<Stopwatch> stopwatch_;

  DISALLOW_COPY_AND_ASSIGN(SessionHandler);
};

}  // namespace mozc
#endif  // MOZC_SESSION_SESSION_HANDLER_H_