Storage.hpp

#ifndef AGENDA_STORAGE_H
#define AGENDA_STORAGE_H

#include "Meeting.hpp"
#include "User.hpp"
#include <functional>
#include <list>
#include <memory>
#include <string>

class Storage {
private:
  /**
  *   default constructor
  */
  Storage();

  /**
  *   disallow the copy constructor and assign operator
  */
  Storage(const Storage & t_another) = delete;
  void operator=(const Storage & t_another) = delete;

  /**
  *   read file content into memory
  *   @return if success, true will be returned
  */
  bool readFromFile(void);

  /**
  *   write file content from memory
  *   @return if success, true will be returned
  */
  bool writeToFile(void);

public:
  /**
  * get Instance of storage
  * @return the pointer of the instance
  */
  static std::shared_ptr<Storage> getInstance(void);

  /**
  *   destructor
  */
  ~Storage();

  // CRUD for User & Meeting
  // using C++11 Function Template and Lambda Expressions

  /**
  * create a user
  * @param a user object
  */
  void createUser(const User & t_user);

  /**
  * query users
  * @param a lambda function as the filter
  * @return a list of fitted users
  */
  std::list<User> queryUser(std::function<bool(const User &)> filter) const;

  /**
  * update users
  * @param a lambda function as the filter
  * @param a lambda function as the method to update the user
  * @return the number of updated users
  */
  int updateUser(std::function<bool(const User &)> filter,
                 std::function<void(User &)> switcher);

  /**
  * delete users
  * @param a lambda function as the filter
  * @return the number of deleted users
  */
  int deleteUser(std::function<bool(const User &)> filter);

  /**
  * create a meeting
  * @param a meeting object
  */
  void createMeeting(const Meeting & t_meeting);

  /**
  * query meetings
  * @param a lambda function as the filter
  * @return a list of fitted meetings
  */
  std::list<Meeting> queryMeeting(std::function<bool(const Meeting &)> filter) const;

  /**
  * update meetings
  * @param a lambda function as the filter
  * @param a lambda function as the method to update the meeting
  * @return the number of updated meetings
  */
  int updateMeeting(std::function<bool(const Meeting &)> filter,
                    std::function<void(Meeting &)> switcher);

  /**
  * delete meetings
  * @param a lambda function as the filter
  * @return the number of deleted meetings
  */
  int deleteMeeting(std::function<bool(const Meeting &)> filter);

  /**
  * sync with the file
  */
  bool sync(void);

private:
  static std::shared_ptr<Storage> m_instance;
  std::list<User> m_userList;
  std::list<Meeting> m_meetingList;
  bool m_dirty;
};

#endif