#include<stdlib.h>
#include<stdio.h>
#include<windows.h>
#include<iostream>
#include<conio.h>
#define random(x) (rand()%x)
using namespace std;

int **map;
char c = 0;
int sign = 0;

char check_snake(char c);

struct snake{
int i;
int j;
struct snake *next;
};

struct snake *generateSnake(){
struct snake *s;
s = (struct snake*)malloc(sizeof(struct snake));
struct snake *p = s;
int x[6] = {2, 3, 4, 5, 5, 5};
int y[6] = {2, 2, 2, 2, 3, 4};
for(int i = 0; i < 6; i++){
struct snake *node; //节点
node = (struct snake*)malloc(sizeof(struct snake));
p->next = node;
p = p->next;
p->i = x[i];
p->j = y[i];
}
p->next = NULL;
return s;
} // 设置蛇的长度和初始位置

void gotoxy(int x, int y)
{
COORD Position;
Position.X = x;
Position.Y = y;
//调用API改变字体位置
SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), Position);
}

// 绘制地图
void draw_map(int **map, int height, int weight){

//绘制地图规则：
//四边形的四边表示墙，用1表示
//其余的用0来表示

void drawSnake(int **map, struct snake *s){
struct snake *p = s->next;
map[p->i][p->j] = 2; // 蛇头
p = p->next;
while(p){
map[p->i][p->j] = 1;
p = p->next;
}
return;
}


void draw_star(int **map,int *star, int height, int weight){
int sum = 0; // 空格子的个数
int index = 0; // 剩下的格子

// 算出空格子的个数
for(int i = 0; i < height ; ++i){
for(int j = 0; j < weight; ++j){
if(map[i][j] == 0)
{
sum += 1;
}
}
}
index = random(sum) + 1; // 在1到sum 中随机的位置生成星星
//生成星星
for(int i = 0; i < height; ++i){
for(int j = 0; j < weight; ++j){
if(map[i][j] == 0){
index -= 1;
}
if(index == 0){
star[0] = i;
star[1] = j;
return ;
}
}
}
return;
}

void update_snake(char c,struct snake *s,int *star){
snake *newsnake;
newsnake = (snake*)malloc(sizeof(snake));
if(c == 'w'){
// 相当于在s 头插一个新节点
newsnake->i = s->next->i - 1;
newsnake->j = s->next->j;

if(map[newsnake->i][newsnake->j] == 1){
// 头插的节点的位置 原本 map[i][j] == 1 表示该位置是墙或者是蛇身了
sign = 3;
}
else if(newsnake->i == star[0] && newsnake->j == star[1]){
newsnake->next = s->next;
s->next = newsnake;
struct snake *q = s;
while(q->next->next != NULL){
gotoxy(q->i, q->j);
printf("■"); // 恢复蛇身
q = q->next;
}
sign = 2;
}

sign = 2;
}
else{
newsnake->next = s->next;
s->next = newsnake;
struct snake *q = s;
while(q->next->next != NULL){
gotoxy(q->i, q->j);
printf("■");
q = q->next;
}
gotoxy(q->i, q->j);
printf("■");
map[q->next->i][q->next->j] = 0;
free(q->next);
q->next = NULL;
}
}
else{
newsnake->i = s->next->i;
newsnake->j = s->next->j + 1;
if(map[newsnake->i][newsnake->j] == 1){
sign = 3;
}
if(newsnake->i == star[0] && newsnake->j == star[1]){
newsnake->next = s->next;
s->next = newsnake;
struct snake *q = s;
while(q->next->next != NULL){
gotoxy(q->i, q->j);
printf("■");
q = q->next;
}
sign = 2;
}
else{
newsnake->next = s->next;
s->next = newsnake;
struct snake *q = s;
while(q->next->next != NULL){
gotoxy(q->i, q->j);
printf("■");
q = q->next;
}
gotoxy(q->i, q->j);
printf("■");
map[q->next->i][q->next->j] = 0;
free(q->next);
q->next = NULL;
}
}
}

// 蛇 移动方向
// 上 119 w
// 下 115 s
// 左 97 a
// 右 100 d
void action_snake(struct snake *s,int *star){
switch(c)
{
//向上
case 'w':
update_snake(c, s,star);
break;
//向下
case 's':
update_snake(c, s,star);
break;
//向左
case 'a':
update_snake(c, s,star);
break;
//向右
case 'd':
update_snake(c, s,star);
break;
}
}

system("cls");
gotoxy(height/2,weight/2);
cout << "游戏结束 " ;
system("pause");

return 0;
}