#include <stdlib.h>
#include <curses.h>


#define ROW 20
#define COL 20

#define ROW_Snake 2
#define COL_Snake 2

#define UP     1
#define DOWN  -1
#define LEFT   2
#define RIGHT -2

int key;
int dir;

int has_snake_node(int I,int J);
void initfood();
int if_snake_die();


struct Snake 
{
	int row_s;
	int col_s;
	struct Snake *next;
};

struct Snake *head = NULL;
struct Snake *tail = NULL;

struct Snake food;

void initNcurse()
{
	initscr();
	keypad(stdscr,1);
	noecho();
}

void game_map(int row,int col)
{
	int i;
	int j;

	move(0,0);

	for(i=0;i<row;i++)
	{
		printw("--");
	}
	printw("\n");
	for(i=1;i<row;i++)
	{
		int j = 0;
		for(j=0;j<=col;j++)
		{
			if(j==0)
			{
				printw("|");
				
			}
			else if(j==col)
			{
				printw("|\n");
			}
			else if(has_snake_node(i,j))
			{
				printw("[]");
			}
			else if(has_food(i,j))
			{
				printw("##");
			}

			else
			printw("  ");
		}
	}
	for(i=0;i<row;i++)
	{
		printw("--");
	}
	printw("\n");
	printw("BY LFF,food %d %d",food.row_s,food.col_s);
}

void add_node()
{
	struct Snake *new = (struct Snake *)malloc(sizeof(struct Snake));
	new->next = NULL;

	switch(dir)
	{
		case UP:
			new->row_s = tail->row_s-1;
			new->col_s = tail->col_s;
			break;
		case DOWN:
                        new->row_s = tail->row_s+1;
                        new->col_s = tail->col_s;
                        break;
		case LEFT:
                        new->row_s = tail->row_s;
                        new->col_s = tail->col_s-1;
                        break;
		case RIGHT:
                        new->row_s = tail->row_s;
                        new->col_s = tail->col_s+1;
                        break;


	}
	tail->next = new;
	tail = new;
}

void delete_node()
{
	struct Snake *p;
	p = head;
	head = head->next;

	free(p);
}



void initsnake_body(int row_snake,int col_snake)
{
	struct Snake *p;
	
	dir = RIGHT;
	
	while(head!=NULL)
	{
		p = head;
		head = head->next;
		free(p);

	}
}
	initfood();
{
	head = (struct Snake *)malloc(sizeof(struct Snake));
	head->row_s = row_snake;
	head->col_s = col_snake;
	head->next = NULL;
	
	tail = head;

	add_node();
	add_node();
	add_node();
	
}

int has_snake_node(int I,int J)
{
	struct Snake *p;
	p = head;
	
	while(p != NULL)
	{
		if(p->row_s == I && p->col_s == J)
		{
			return 1;
		}
		p = p->next;
	}
	return 0;
}

void initfood()
{
	int x = rand()%18+1;
	int y = rand()%18+1;

	food.row_s = x;
	food.col_s = y;

}

int has_food(int I,int J)
{
	if(food.row_s == I && food.col_s == J)
	{
		return 1;
	}
	return 0;
}


void move_snake()
{
	add_node();
	
	if(has_food(tail->row_s,tail->col_s))
	{
		initfood();
	}
	else
	{
		delete_node();
	}
	if(if_snake_die())
	{
		initsnake_body(ROW_Snake,COL_Snake);
	}

}



void refresh_map()
{
        while(1)
        {
                move_snake();
                game_map(ROW,COL);
                refresh();
                usleep(100000);
        }

}

void turn(int direction)
{
	if(abs(dir) != abs(direction))
	{
		dir = direction;
	}
}


void chang_dir()
{
	while(1)
	{
		key = getch();
		switch(key)
		{
		case KEY_DOWN:
			turn(DOWN);
			break;
		case KEY_UP:
                        turn(UP);
                        break;
		case KEY_LEFT:
                        turn(LEFT);
                        break;
		case KEY_RIGHT:
                        turn(RIGHT);
                        break;


		}

	}

}

int if_snake_die()
{
	struct Snake *p;
	p = head;

	if(tail->row_s == 0 || tail->col_s == 0 || tail->row_s == 20 || tail->col_s == 20)
	{
		return 1;	
	}

	while(p->next!=NULL)
	{
		if(p->row_s == tail->row_s && p->col_s == tail->col_s)
		{
			return 1;
		}
		
		p = p->next;
	}
	return 0;
}

int main()
{

	pthread_t t1;
	pthread_t t2;

	initNcurse();
//	initscr();	

	initsnake_body(ROW_Snake,COL_Snake);
	game_map(ROW,COL);

	pthread_create(&t1,NULL,refresh_map,NULL);
	pthread_create(&t2,NULL,chang_dir,NULL);

	while(1);

	getch();
	endwin();
	return 0;
}