//  filename : queue.h
//  written by Ting-jen Yen
//  description: This file define the structures of the classes
//		 of Queue_item and Queue, which are used to
//		 handle requests on the clients before send
//		 through network one by one.
//
#ifndef _QUEUE_H
#define _QUEUE_H

#include <pthread.h>

#ifndef NULL

#  define _LOCAL_NULL
#  define NULL 0

#endif

#define NO_REQUEST 0
#define VIEW_NEW_IMAGE 1
#define GET_MORE_DATA 2
#define CLOSE_CONNECTION 3
#define GET_LIST 4

class Queue_item {

public:

  Queue_item (void);
  Queue_item (int, int, int, int, int);
  Queue_item (int, int, int, int, int, int);
  int request_type;
  int level;
  int st_col;
  int en_col;
  int st_row;
  int en_row;
  int depend;

  Queue_item * next;
};

class Queue {

public:

  Queue (void);
  ~Queue (void);
  void startup(void);
  void stop(void);
  Queue_item *dequeue(void);
  void clean(void);
  int enqueue(int, int, int, int, int);
  int enqueue(int, int, int, int, int, int);
  int enqueue(int);
  void reduce(int, int, int, int, int);
  int length(void);

private:

  int Length;
  Queue_item * head;
  Queue_item * tail;
};

#ifdef _LOCAL_NULL
# undef NULL
# undef _LOCAL_NULL
#endif

#endif