#include <stdio.h>
#include <conio.h>
#include <malloc.h>
#include <stdlib.h>
#include <time.h>
#include <easyx.h>
#define up 72
#define down 80
#define lift 75
#define right 77
int move = 72;

typedef struct ac
{
	int x;
	int y;
	struct ac* next;
}LinkList;

LinkList* createLink();//创建链表
void create_food(int* position);//添加食物
void create(LinkList* head, int* end);//创建主角
LinkList* changeLink(LinkList* head, int* end, int nodemun);//根据运动情况，改变链表数据
void add_node(LinkList *head,int *nodemun,int *end);//吃到食物后添加节点
void print_score_grade(int nodemun, int grade);//打印等级和分数
void chose_speed(int nodemun);//根据等级选择蛇的移动速度
void create_map();//创建地图
void graph_thinks();
int check(LinkList *head,int nodemun);//检查游戏的运行的正确性
//==============================================================
LinkList* createLink()
{
	LinkList* head;
	head = (LinkList*)malloc(sizeof(struct ac));
	if (head == NULL)
		exit(0);
	head->x = 250;
	head->y = 250;
	head->next = NULL;
	return head;
}
void create_food(int* position)
{
	int x, y;
	srand(time(NULL));//种子
	x = rand() % 49;//随机数确定食物位置
	y = rand() % 39;
	position[0] = x * 10;
	position[1] = y * 10;
	setfillcolor(RGB(0, 255, 255));//打印食物
	solidrectangle(position[0], position[1], position[0] + 10, position[1] + 10);
}
void create(LinkList * head, int* end)
{
	LinkList* p;
	p = head;
	setfillcolor(RGB(0, 255, 255));
	while (p->next != NULL)
	{
		solidrectangle(p->x, p->y, p->x + 10, p->y + 10);
		p = p->next;
	}
	solidrectangle(p->x, p->y, p->x + 10, p->y + 10);
	if (end != NULL)//抹去上一个的蛇尾
	{
		setfillcolor(BLACK);
		solidrectangle(end[0], end[1], end[0] + 10, end[1] + 10);
	}
}
LinkList* changeLink(LinkList * head, int* end, int nodemun)
{
	int i;
	LinkList* new_node;
	LinkList* current;
	LinkList* p;
	new_node = (LinkList *)malloc(sizeof(struct ac));
	if (new_node == NULL)
		exit(0);
	current = head;
	new_node->next = head;
	while (current->next != NULL)//寻找蛇尾
	{
		current = current->next;
	}
	
	switch (move)//添加新的头节点，删除尾节点
	{
	case up:
		new_node->x = head->x;
		new_node->y = head->y - 10;
		end[0] = current->x;
		end[1] = current->y;
		free(current);
		current = NULL;
		break;
	case down:
		new_node->x = head->x;
		new_node->y = head->y + 10;
		end[0] = current->x;
		end[1] = current->y;
		free(current);
		current = NULL;
		break;
	case right:
		new_node->x = head->x + 10;
		new_node->y = head->y;
		end[0] = current->x;
		end[1] = current->y;
		free(current);
		current = NULL;
		break;
	case lift:
		new_node->x = head->x - 10;
		new_node->y = head->y;
		end[0] = current->x;
		end[1] = current->y;
		free(current);
		current = NULL;
		break;
	}
	p = new_node;
	for (i = 1; i < nodemun; i++)//寻找新的蛇尾
	{
		p = p->next;
	}
	p->next = NULL;//将新的尾节点指向NULL
	return new_node;//返回新的头节点
}
void add_node(LinkList * head, int* nodemun,int *end)
{
	int i = 1;
	int tail[2], sec_tail[2];
	LinkList* current;
	LinkList* new_node;

	new_node = (LinkList *)malloc(sizeof(struct ac));
	if (new_node == NULL)
		exit(0);
	current = head;

	if (*nodemun >1)//蛇有两个节点及以上
	{
		while (current->next != NULL)
		{
			if (i == *nodemun - 1)//寻找倒数第二个节点，并保存其值
			{
				sec_tail[0] = current->x;
				sec_tail[1] = current->y;
				current = current->next;
			}
			else
			{
				i++;
				current = current->next;
			}
		}
		tail[0] = current->x;
		tail[1] = current->y;

		//根据蛇尾运动方向添加节点
		if (tail[0] > sec_tail[0])
		{
			end[0] = end[0] + 10;
			new_node->x = current->x + 10;
			new_node->y = current->y;
		}
		if (tail[0] < sec_tail[0])
		{
			end[0] = end[0] - 10;
			new_node->x = current->x - 10;
			new_node->y = current->y;
		}
		if (tail[1] > sec_tail[1])
		{
			end[1] = end[1] + 10;
			new_node->x = current->x;
			new_node->y = current->y + 10;
		}
		if (tail[1] < sec_tail[1])
		{
			end[1] = end[1] - 10;
			new_node->x = current->x;
			new_node->y = current->y - 10;
		}
	}


	if (*nodemun == 1)//蛇只有一个节点
	{
		switch (move)
		{
		case up:
			end[1] = end[1] + 10;
			new_node->x = current->x;
			new_node->y = current->y + 10; break;
		case down:
			end[1] = end[1] - 10;
			new_node->x = current->x;
			new_node->y = current->y - 10; break;
		case right:
			end[0] = end[0] - 10;
			new_node->x = current->x - 10;
			new_node->y = current->y; break;
		case lift:
			end[0] = end[0] + 10;
			new_node->x = current->x + 10;
			new_node->y = current->y; break;
		}
	}
	new_node->next = NULL;
	current->next = new_node;
	*nodemun = *nodemun+1;
}
void print_score_grade(int nodemun,int grade)
{
	wchar_t ch[5];//宽字节
	wchar_t ch2[2];
	
	setbkmode(TRANSPARENT);//设置背景模式
	settextcolor(RGB(0, 255, 255));
	settextstyle(20, 0, _T("宋体"));

	setfillcolor(BLACK);
	solidrectangle(580, 150, 700, 170);
	solidrectangle(580, 100, 700, 120);

	swprintf(ch,5, _T("%d"), nodemun *10-10);
	swprintf(ch2, 2, _T("%d"), grade);

	outtextxy(580, 150, ch);
	outtextxy(580, 100, ch2);

	
}
void chose_speed(int nodemun)
{
	switch (nodemun / 15)
	{
	case 0:Sleep(300); break;
	case 1:Sleep(250); break;
	case 2:Sleep(200); break;
	case 3:Sleep(150); break;
	case 4:Sleep(100); break;
	default:Sleep(100);
	}
}
void create_map()
{
	//绘图
	initgraph(850, 400);
	setfillcolor(BLACK);
	solidrectangle(0, 0, 850, 400);

	//LOGFONT f;
	//gettextstyle(&f);                     // 获取当前字体设置
	//f.lfHeight = 48;                      // 设置字体高度为 48
	//_tcscpy(f.lfFaceName, _T("黑体"));    // 设置字体为“黑体”(高版本 VC 推荐使用 _tcscpy_s 函数)
	//f.lfQuality = ANTIALIASED_QUALITY;    // 设置输出效果为抗锯齿  
	//settextstyle(&f);                     // 设置字体样式

	setbkmode(TRANSPARENT);//设置背景模式
	settextcolor(RGB(0, 255, 255));
	settextstyle(20, 0, _T("宋体"));
	outtextxy(250, 150, _T("wlecome to play the game!"));
	outtextxy(50, 350, _T("Press any key to continue..."));
	system("pause");

	solidrectangle(0, 0, 850, 400);
	setlinecolor(RGB(0, 255, 255));
	line(500, 0, 500, 400);
	outtextxy(520, 150, _T("Score:"));
	outtextxy(520, 100, _T("Grade:"));
	outtextxy(505, 300, _T("the game is created by jack shi"));
}
void graph_thinks(int nodemun)
{
	wchar_t ch[5];
	setfillcolor(BLACK);
	solidrectangle(0, 0, 850, 400);
	setbkmode(TRANSPARENT);//设置背景模式
	settextcolor(RGB(0, 255, 255));
	settextstyle(40, 0, _T("宋体"));
	outtextxy(300, 100, _T(" game over!"));
	outtextxy(200, 200, _T(" your grade :     points"));

	swprintf(ch, 5, _T("%d"), nodemun * 10 - 10);
	outtextxy(470,200,ch);
}
int check(LinkList *head,int nodemun)
{
	int i;
	LinkList* current;
	if (nodemun >= 5)//蛇有5个节点以上
	{
		current = head->next->next->next->next;//current指向第5个节点
		for (i = 5; i <= nodemun; i++)//判断蛇是否吃到自己
		{
			if (head->x == current->x && head->y == current->y)
			{
				return 0;
			}
			current = current->next;
			i++;
		}
	}
	if (head->x < 0 || head->x>490 || head->y < 0 || head->y>390)//判断蛇身是否超出游戏界面
		return 0;
	return 1;
}
void main()
{
	int kb;
	LinkList* head;
	int end[2];//存取蛇尾坐标
	int position[2];//存取食物位置
	int nodemun = 1;//蛇的长度
	create_map();
	//=============================
	head = createLink();
	create_food(position);
	print_score_grade(nodemun,nodemun/15+1);
	while (1)//游戏中
	{
		create(head, end);
		chose_speed(nodemun);//选择速度
		if (_kbhit())//获取鼠标操作
		{
			_getch();
			kb = _getch();
			//不能向当前蛇头移动方向的反方向运动
			if (!(kb == up && move == down || kb == down && move == up || kb == right && move == lift || kb == lift && move == right))
				move = kb;
		}
		head = changeLink(head, end, nodemun);//根据蛇的移动改变链表
		if (check(head,nodemun) == 0)//合法性检测
			break;
		if (head->x == position[0] && head->y == position[1])//判断是否吃到食物
			{
				add_node(head, &nodemun,end);//吃到食物，添加新节点
				print_score_grade(nodemun,nodemun/15+1);//打印等级和分数
				create_food(position);//创建新食物
			}
	}
	graph_thinks(nodemun);
	system("pause");
	closegraph();
}