#include <stdio.h>
#include <windows.h>
#include<conio.h>
#include <stdlib.h>
#include<time.h>

#define X 23//地图的x轴
#define Y 75//地图的y轴

#define UP 0
#define DOWN 1
#define LEFT 2
#define RIGHT 3

#define WAIT_TIME 180//等待蛇刷新的时间,可以说是速度  修改可变速

int map_0[X][Y];//地图
int Snake[X*Y][2]; // 蛇
int Slength; //蛇的长度
int direction;
int score=0;

bool pdEatFood=false;

void csh();
void huaMap();
void huaSnake();
void gotoxy(int x,int y);
void move();
void intokey();
int check(int x,int y);
void putfood();
bool gameover();
void dy_fs();

int main() {
	csh();
	huaMap();
	putfood();
	Sleep(5000);
	while(1) {
		huaSnake();
		Sleep(WAIT_TIME);
		intokey();
		move();
		dy_fs();
		if(gameover()) {
			system("cls");          //清除屏幕内容
			printf("Game Over\n");
			system("pause");
			getchar();
			break;
		}
		if(map_0[Snake[0][0]][Snake[0][1]]==-1) {
			map_0[Snake[0][0]][Snake[0][1]]=0;
			pdEatFood=true;
			putfood();
			score+=1;
		}
	}
	return 0;
}
void csh() { //初始化
	srand((unsigned)time(NULL)); //设置种子为现在的时间
	Slength=4;
	gotoxy(0,0);
	CONSOLE_CURSOR_INFO cursor_info = {1, 0}; //清除光标
	SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &cursor_info);
	int x,y;
	Snake[0][0]=X/2;
	Snake[0][1]=Y/2;
	for(x=0; x<X; x++) {
		map_0[x][0]=1;
		map_0[x][Y-1]=1;
	}
	for(y=0; y<Y-1; y++) {
		map_0[0][y]=1;
		map_0[X-1][y]=1;
	}
	for(x=1; x<4; x++) {	//初始化蛇的坐标
		Snake[x][0]=Snake[0][0]+x;
		Snake[x][1]=Snake[0][1];
	}
	direction=UP;

}
void huaMap() { //画地图
	int x,y;
	for(x=0; x<X; x++) {
		for(y=0; y<Y; y++) {
			if(map_0[x][y]==1) {
				printf("#");
			}
			if(map_0[x][y]==0) {
				printf(" ");
			}
		}
		printf("\n");
	}
}
void huaSnake() { //画蛇
	int x;
	gotoxy(Snake[0][0],Snake[0][1]);
	printf("O");
	for(x=1; x<Slength; x++) {
		gotoxy(Snake[x][0],Snake[x][1]);
		printf("#");	
	}
}
void gotoxy(int i,int j) { //移动光标
	COORD position= {j,i};
	SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE),position);
}
void move() {
	int i;
	gotoxy(Snake[Slength-1][0],Snake[Slength-1][1]);//擦除尾巴
	printf(" ");
	for(i=Slength-1; i>0; i--) { //从尾巴开始，每一个点的位置等于它前面一个点的位置
		Snake[i][0]=Snake[i-1][0];
		Snake[i][1]=Snake[i-1][1];
	}
	switch(direction) {
		case UP:
			Snake[0][0]--;
			break;
		case DOWN:
			Snake[0][0]++;
			break;
		case LEFT:
			Snake[0][1]--;
			break;
		case RIGHT:
			Snake[0][1]++;
			break;
	}
	if(pdEatFood) {
		Slength++;
		pdEatFood=false;
	}

}
void intokey() {
	if(kbhit()!=0) {        //kbhit()函数 检查当前是否有键盘输入，若有则返回一个非0值，否则返回0
		char in;
		while(!kbhit()==0)  //如果玩家输入了多个按键，以最后一个按键为准
			in=getch();
		switch(in) {
			case 'w':
			case 'W':
				if(direction!=DOWN)         //防止缩头
					direction=UP;
				break;
			case 's':
			case 'S':
				if(direction!=UP)
					direction=DOWN;
				break;
			case 'a':
			case 'A':
				if(direction!=RIGHT)
					direction=LEFT;
				break;
			case 'd':
			case 'D':
				if(direction!=LEFT)
					direction=RIGHT;
				break;
			case 'p':
			case 'P':
				gotoxy(X,0);
				system("pause");
				gotoxy(X,0);
				printf("                   ");  //	消去下面的按任意键继续
				break;
		}
	}
}
int check(int ii,int jj) { // 检查是否能投放食物
	if(map_0[ii][jj]==1)
		return 0;
	if(ii==0 || jj==0 || ii==X-1 || jj==Y-1)
		return 0;
	int i;
	for(i=0; i<Slength; i++) {
		if(ii==Snake[i][0] && jj==Snake[i][1])
			return 0;
	}
	return 1;
}
void putfood() {
	int i,j;
	do {
		i=rand()%X;
		j=rand()%Y;
	} while(check(i,j)==0);
	map_0[i][j]=-1;
	gotoxy(i,j);
	printf("$");
}
bool gameover() {
	bool isgameover=false;
	int sX,sY;
	sX=Snake[0][0],sY=Snake[0][1];
	if(sX==0 || sX==X-1 || sY==0 || sY==Y-1)
		isgameover=true;
	int i;
	for(i=1; i<Slength; i++) {
		if(sX==Snake[i][0] && sY==Snake[i][1])
			isgameover=true;
	}
	return isgameover;
}
void dy_fs() {
	gotoxy(X,0);
	printf("(c)Geek------2018.1.22");
	gotoxy(X+1,0);
	printf("最终得分: %d",score);
}