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

using namespace std;

const int WIDTH = 30;
const int HEIGHT = 15;
const int OBSTACLE_COUNT = 10;
const int NORMAL_FRUIT_SCORE = 10;
const int HIGH_SCORE_FRUIT_SCORE = 30;
const int WIN_SCORE = 500;

bool gameover, paused, highScoreFruit;
int x, y, fruitX, fruitY, highScoreFruitX, highScoreFruitY, score;
int tailX[100], tailY[100], nTail;
int x2, y2, score2, tailX2[100], tailY2[100], nTail2;
int obstacles[OBSTACLE_COUNT][2];
enum Direction { STOP = 0, LEFT, RIGHT, UP, DOWN };
Direction dir, dir2;
bool twoSnakeMode = false; // 增加模式选择标志

void gotoxy(int x, int y) {
    COORD coord;
    coord.X = x;
    coord.Y = y;
    SetConsoleCursorPosition(GetStdHandle(STD_OUTPUT_HANDLE), coord);
}

void SetConsoleCursor(bool visible) {
    CONSOLE_CURSOR_INFO cci;
    cci.dwSize = 1;
    cci.bVisible = visible ? TRUE : FALSE;
    SetConsoleCursorInfo(GetStdHandle(STD_OUTPUT_HANDLE), &cci);
}

void InitializeObstacles() {
    for (int i = 0; i < OBSTACLE_COUNT; ++i) {
        do {
            obstacles[i][0] = rand() % WIDTH;
            obstacles[i][1] = rand() % HEIGHT;
        } while ((obstacles[i][0] == x && obstacles[i][1] == y) || (twoSnakeMode && obstacles[i][0] == x2 && obstacles[i][1] == y2));
    }
}

void GenerateFruit(int& fruitX, int& fruitY) {
    int tt;
    do {
        tt = 0;
        fruitX = rand() % (WIDTH - 2) + 1;
        fruitY = rand() % (HEIGHT - 2) + 1;
        for (int i = 0; i < nTail; ++i)
            if (fruitX == tailX[i] && fruitY == tailY[i]) tt = 1;
        for (int i = 0; i < OBSTACLE_COUNT; ++i)
            if (fruitX == obstacles[i][0] && fruitY == obstacles[i][1]) tt = 1;
        if (fruitX == x && fruitY == y) tt = 1;
        if (twoSnakeMode && fruitX == x2 && fruitY == y2) tt = 1;
    } while (tt == 1);
}

void Setup() {
    gameover = paused = highScoreFruit = false;
    dir = dir2 = STOP;
    x = WIDTH / 2;
    y = HEIGHT / 2;
    if (twoSnakeMode) {
        x2 = WIDTH / 3;
        y2 = HEIGHT / 3;
        score2 = 0;
        nTail2 = 0;
    }
    fruitX = rand() % WIDTH;
    fruitY = rand() % HEIGHT;
    score = 0;
    nTail = 0;
    InitializeObstacles();
}

void Draw() {
    gotoxy(0, 0); // 将光标移动到控制台的左上角

    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 << "#";

            bool isObstacle = false;
            for (int k = 0; k < OBSTACLE_COUNT; ++k) {
                if (obstacles[k][0] == j && obstacles[k][1] == i) {
                    cout << "*";
                    isObstacle = true;
                    break;
                }
            }

            if (!isObstacle) {
                if (i == y && j == x)
                    cout << "O";
                else if (twoSnakeMode && i == y2 && j == x2)
                    cout << "X";
                else if (i == fruitY && j == fruitX)
                    cout << "F";
                else if (i == highScoreFruitY && j == highScoreFruitX && highScoreFruit)
                    cout << "H";
                else {
                    bool printTail = false;
                    for (int k = 0; k < nTail; k++) {
                        if (tailX[k] == j && tailY[k] == i) {
                            cout << "o";
                            printTail = true;
                            break;
                        }
                    }
                    if (twoSnakeMode) {
                        for (int k = 0; k < nTail2; k++) {
                            if (tailX2[k] == j && tailY2[k] == i) {
                                cout << "x";
                                printTail = true;
                                break;
                            }
                        }
                    }
                    if (!printTail)
                        cout << " ";
                }
            }

            if (j == WIDTH - 1)
                cout << "#";
        }
        cout << endl;
    }

    for (int i = 0; i < WIDTH + 2; i++)
        cout << "#";
    cout << endl;
    cout << "Score1: " << score;
    if (twoSnakeMode) cout << " Score2: " << score2;
    cout << endl;

    if (paused)
        cout << "Paused. Press 'R' to resume." << endl;
    else
        cout << "                                           " << endl;
}

void Input() {
    if (_kbhit()) {
        switch (_getch()) {
        case 'a':
            dir = LEFT;
            break;
        case 'd':
            dir = RIGHT;
            break;
        case 'w':
            dir = UP;
            break;
        case 's':
            dir = DOWN;
            break;
        case 'j':
            if (twoSnakeMode) dir2 = LEFT;
            break;
        case 'l':
            if (twoSnakeMode) dir2 = RIGHT;
            break;
        case 'i':
            if (twoSnakeMode) dir2 = UP;
            break;
        case 'k':
            if (twoSnakeMode) dir2 = DOWN;
            break;
        case 'p':
            paused = !paused;
            break;
        case 'q':
            gameover = true;
            break;
        }
    }
}

void MoveSnake(int& x, int& y, int tailX[], int tailY[], int& nTail, Direction dir) {
    int prevX = tailX[0];
    int prevY = tailY[0];
    int prev2X, prev2Y;
    tailX[0] = x;
    tailY[0] = y;

    for (int i = 1; i < nTail; i++) {
        prev2X = tailX[i];
        prev2Y = tailY[i];
        tailX[i] = prevX;
        tailY[i] = prevY;
        prevX = prev2X;
        prevY = prev2Y;
    }

    switch (dir) {
    case LEFT:
        x--;
        break;
    case RIGHT:
        x++;
        break;
    case UP:
        y--;
        break;
    case DOWN:
        y++;
        break;
    default:
        break;
    }

    if (x >= WIDTH) x = 0; else if (x < 0) x = WIDTH - 1;
    if (y >= HEIGHT) y = 1; else if (y <= 0) y = HEIGHT - 1;

    for (int i = 0; i < nTail; i++)
        if (tailX[i] == x && tailY[i] == y)
            gameover = true;

    for (int i = 0; i < OBSTACLE_COUNT; ++i) {
        if (x == obstacles[i][0] && y == obstacles[i][1]) {
            gameover = true;
        }
    }
}

void Algorithm() {
    if (!paused) {
        MoveSnake(x, y, tailX, tailY, nTail, dir);
        if (twoSnakeMode) {
            MoveSnake(x2, y2, tailX2, tailY2, nTail2, dir2);
        }

        static int timer = 0;
        const int timerThreshold = 50;

        timer++;
        if (timer == timerThreshold) {
            timer = 0;
            highScoreFruit = true;
            GenerateFruit(highScoreFruitX, highScoreFruitY);
        }

        if (x == highScoreFruitX && y == highScoreFruitY) {
            score += HIGH_SCORE_FRUIT_SCORE;
            highScoreFruit = false;
            nTail += 2;
        }
        if (twoSnakeMode && x2 == highScoreFruitX && y2 == highScoreFruitY) {
            score2 += HIGH_SCORE_FRUIT_SCORE;
            highScoreFruit = false;
            nTail2 += 2;
        }

        if (x == fruitX && y == fruitY) {
            score += NORMAL_FRUIT_SCORE;
            nTail++;
            GenerateFruit(fruitX, fruitY);
        }
        if (twoSnakeMode && x2 == fruitX && y2 == fruitY) {
            score2 += NORMAL_FRUIT_SCORE;
            nTail2++;
            GenerateFruit(fruitX, fruitY);
        }

        if (score >= WIN_SCORE) {
            gameover = true;
            gotoxy(0, HEIGHT + 3);
            Draw();
            cout << "Player 1 wins!" << endl;
            return;
        }

        if (twoSnakeMode && score2 >= WIN_SCORE) {
            gameover = true;
            gotoxy(0, HEIGHT + 3);
            Draw();
            cout << "Player 2 wins!" << endl;
            return;
        }
    }
}

void Index() {
    cout << "Press 1 for single snake mode" << endl;
    cout << "Press 9 for two snakes mode" << endl;
    cout << "Press 2 to exit\nPress p to pause\nPress r to resume\nPress q to quit" << endl;
    cout << "Rules:\nNormal fruit 'F' = 10 scores, increases length by 1;\nHigh-score fruit 'H' = 30 scores, increases length by 2;\nReach 500 scores to win!" << endl;
}

int main() {
    SetConsoleOutputCP(CP_UTF8);
    srand(time(0));
    Index();
    while (true) {
        int flag = 0;
        switch (_getch()) {
        case '1':
            twoSnakeMode = false;
            Setup();
            while (!gameover) {
                Draw();
                Input();
                Algorithm();
                Sleep(100);
            }
            gotoxy(0, WIDTH + 1);
            Index();
            break;
        case '9':
            twoSnakeMode = true;
            Setup();
            while (!gameover) {
                Draw();
                Input();
                Algorithm();
                Sleep(100);
            }
            gotoxy(0, WIDTH + 1);
            Index();
            break;
        case '2':
            flag = 1;
            break;
        }
        if (flag) break;
    }
    SetConsoleCursor(true);
    return 0;
}