#include <iostream>
#include <conio.h>
#include <windows.h>
#include <vector>

using namespace std;

// 定义屏幕大小
const int width = 20;
const int height = 20;

// 蛇的位置和方向
int x, y;
int fruitX, fruitY;
int score;
enum eDirection { STOP = 0, LEFT, RIGHT, UP, DOWN };
eDirection dir;

// 蛇的身体
vector<pair<int, int>> snakeBody;

// 设置控制台光标位置
void gotoxy(int x, int y) {
    COORD coord;
    coord.X = x;
    coord.Y = y;
    SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), coord);
}

// 隐藏控制台光标
void hideCursor() {
    HANDLE consoleHandle = GetStdHandle(STD_OUTPUT_HANDLE);
    CONSOLE_CURSOR_INFO info;
    info.dwSize = 100;
    info.bVisible = FALSE;
    SetConsoleCursorInfo(consoleHandle, &info);
}

// 初始化游戏
void Setup() {
    hideCursor();
    dir = STOP;
    x = width / 2;
    y = height / 2;
    fruitX = rand() % width;
    fruitY = rand() % height;
    score = 0;
    snakeBody.clear();
    snakeBody.push_back(make_pair(x, y));
}

// 绘制游戏界面
void Draw() {
    system("cls");
    for (int i = 0; i < width + 2; i++)
        cout << "#";
    cout << endl;

    for (int i = 0; i < height; i++) {
        for (int j = 0; j < width; j++) {
            if (j == 0)
                cout << "#";
            if (i == y && j == x)
                cout << "O";
            else if (i == fruitY && j == fruitX)
                cout << "F";
            else {
                bool print = false;
                for (auto part : snakeBody) {
                    if (part.first == j && part.second == i) {
                        cout << "o";
                        print = true;
                        break;
                    }
                }
                if (!print)
                    cout << " ";
            }
            if (j == width - 1)
                cout << "#";
        }
        cout << endl;
    }

    for (int i = 0; i < width + 2; i++)
        cout << "#";
    cout << endl;
    cout << "Score: " << score << endl;
}

// 处理用户输入
void Input() {
    if (_kbhit()) {
        switch (_getch()) {
        case 'a':
            if (dir != RIGHT)
                dir = LEFT;
            break;
        case 'd':
            if (dir != LEFT)
                dir = RIGHT;
            break;
        case 'w':
            if (dir != DOWN)
                dir = UP;
            break;
        case 's':
            if (dir != UP)
                dir = DOWN;
            break;
        case 'x':
            exit(0);
            break;
        }
    }
}

// 游戏逻辑更新
void Logic() {
    pair<int, int> prevHead = snakeBody[0];
    pair<int, int> newHead = prevHead;

    switch (dir) {
    case LEFT:
        newHead.first--;
        break;
    case RIGHT:
        newHead.first++;
        break;
    case UP:
        newHead.second--;
        break;
    case DOWN:
        newHead.second++;
        break;
    default:
        break;
    }

    // 检查是否吃到水果
    if (newHead.first == fruitX && newHead.second == fruitY) {
        score++;
        fruitX = rand() % width;
        fruitY = rand() % height;
    } else {
        snakeBody.pop_back();
    }

    // 检查是否撞到边界或自己
    if (newHead.first < 0 || newHead.first >= width || newHead.second < 0 || newHead.second >= height) {
        cout << "Game Over!" << endl;
        system("pause");
        exit(0);
    }
    for (auto part : snakeBody) {
        if (part.first == newHead.first && part.second == newHead.second) {
            cout << "Game Over!" << endl;
            system("pause");
            exit(0);
        }
    }

    snakeBody.insert(snakeBody.begin(), newHead);
}

int main() {
    Setup();
    while (true) {
        Draw();
        Input();
        Logic();
        Sleep(100);
    }
    return 0;
}