#include<stdio.h>
#include<conio.h>
#define max_q_len 8
typedef struct
{
	char name[20];
	char id[10];
}	student;
student queue[max_q_len];
int start=0;
int rear=0;
student get_student();
void add_to_que(int strt,int * rear,student item);
student remove_from_que(int * start,int rer);
void show_que_data(int strt,int rer);
int is_full(int strt,int rer);
int is_empty(int strt,int rer);
void main_menu(void);
void is_del(student tmp);
int main()
{
	textbackground(1);
	char c,t;
	while (c!='4')
	{
		clrscr();
		main_menu();
		c=getch();
		switch (c)
		{
			  case '1':
				if (is_full(start,rear))
				{
					printf("\n\t\t\t\tQueue is Full!");
					getchar();
				}
				else
				{
					add_to_que(start,&rear,get_student());
				}
				break;
			  case '2':
				student temp;
				temp=remove_from_que(&start,rear);
				if (!is_empty(start,rear))
					is_del(temp);
				break;
			  case '3':
				show_que_data(start,rear);
				getchar();
				break;
			  case '4':
				return 0;
			  default:
				printf("\n\t\t\tBad choise!");
				printf("\n\n\n\t\t\t\tPress enter to continue!");
				t=getch();
				clrscr();
		}
	}
	return 0;
}
student get_student()
{
	student temp;
	clrscr();
	printf("\n\t\t-----------------------------------------------------");
	printf("\n\t\t***************  Enter student's info  **************");
	printf("\n\t\t-----------------------------------------------------");
	printf("\n\n\t\tName:");
	scanf("%s",temp.name);
	printf("\n\t\tID:");
	scanf("%s",temp.id);
	return temp;
}
void add_to_que(int strt,int * rer,student item)
{
	*rer=(*rer+1)%max_q_len;
	queue[*rer]=item;
}
student remove_from_que(int * strt,int rer)
{
	clrscr();
	if (is_empty(*strt,rer))
		{
			printf("\n\n\n\t\t\t\t Queue Is Empty!");
			getchar();
			getchar();
			return queue[*strt];
		}
	else
		{
			*strt=(*strt+1)%max_q_len;
			return  queue[*strt];
		}

}
void show_que_data(int strt,int rer)
{
	clrscr();
	if (is_empty(strt,rer))
		{
			printf("\n\t\t\t\t Queue is empty!");
			getchar();
		}
	else
		//     error in index [i]
		for (int i=(strt+1)%max_q_len;i!=(rer+1)%max_q_len;i=(++i)%max_q_len)
		{
			printf("\n------------------------------------");
			printf("\n\t\tIndex:%d\n\t\t------------------\n\t\tName:%s",i,queue[i].name);
			printf("\n\t\tID:%s\n",queue[i].id);
		}

}
int is_full(int strt,int rer)
{
	if(strt==((rer+1)%max_q_len))
		return 1;
	else
		return 0;
}
int is_empty(int strt,int rer)
{
	if (strt==rer)
		return 1;
	else
		return 0;
}
void main_menu()
{
	printf("\n\t\t--------------This is an queue Example---------------");
	printf("\n\t\t*****************************************************");
	printf("\n");
	printf("\n\t\t		1: Add new item to queue.");
	printf("\n\t\t		2: Remove an item from queue.");
	printf("\n\t\t		3: Show the queue records.");
	printf("\n\t\t		4: Exit.");
	printf("\n\t\t	     -------------------------------------");
	printf("\n\t\t		Enter your choise:");

}
void is_del(student tmp)
{
	clrscr();
	printf("\n\n\n------------------------------------------------------------------------------");
	printf("\n*************************** This Record Is Deleted *************************** ");
	printf("\n------------------------------------------------------------------------------");
	printf("\n\n\n\t\t\t\t Name :%s",tmp.name);
	printf("\n\n\t\t\t\t ID :%s",tmp.id);
	getchar();
	getchar();
}