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// An interface of session manager of Mozc server.

#ifndef MOZC_SESSION_SESSION_HANDLER_INTERFACE_H_
#define MOZC_SESSION_SESSION_HANDLER_INTERFACE_H_

#include "absl/strings/string_view.h"

namespace mozc {

namespace commands {
class Command;
}  // namespace commands

namespace session {
class SessionObserverInterface;
}  // namespace session

class SessionHandlerInterface {
 public:
  SessionHandlerInterface() = default;

  SessionHandlerInterface(const SessionHandlerInterface &) = delete;
  SessionHandlerInterface &operator=(const SessionHandlerInterface &) = delete;

  virtual ~SessionHandlerInterface() = default;

  // Returns true if SessionHandle is available.
  virtual bool IsAvailable() const = 0;

  virtual bool EvalCommand(commands::Command *command) = 0;

  // Starts watch dog timer to cleanup sessions.
  virtual bool StartWatchDog() = 0;

  virtual void AddObserver(session::SessionObserverInterface *observer) = 0;

  virtual absl::string_view GetDataVersion() const = 0;
};

}  // namespace mozc

#endif  // MOZC_SESSION_SESSION_HANDLER_INTERFACE_H_