const canvas = document.getElementById('sand');
const ctx = canvas.getContext('2d');
canvas.width = window.innerWidth - 12;
canvas.height = window.innerHeight - 12;

const gridSize = 10;
const gridWidth = Math.floor(canvas.width / gridSize);
const gridHeight = Math.floor(canvas.height / gridSize);
const grid = Array(gridHeight).fill().map(() => Array(gridWidth).fill(0));

let mouseDown = false;
let playerAdded = false;
let keys = new Set();

canvas.addEventListener('mousedown', (e) => {
    mouseDown = true;
    addSand(e);
});

canvas.addEventListener('mouseup', () => {
    mouseDown = false;
});

canvas.addEventListener('mousemove', (e) => {
    if (mouseDown) {
        addSand(e);
    }
});

canvas.addEventListener('touchstart', (e) => {
    mouseDown = true;
    e.preventDefault();
    addSand(e.touches[0]);
});

canvas.addEventListener('touchend', () => {
    mouseDown = false;
});

canvas.addEventListener('touchmove', (e) => {
    if (mouseDown) {
        e.preventDefault();
        addSand(e.touches[0]);
    }
});

window.addEventListener('keydown', (e) => {
    keys.add(e.key);
});

window.addEventListener('keyup', (e) => {
    keys.delete(e.key);
});

window.addEventListener('keydown', (e) => {
    if (e.key === ' ' && !playerAdded) {
        addPlayer();
        playerAdded = true;
    }
});

window.addEventListener('keydown', (e) => {
    // reset the canvas
    if (e.key === 'r') {
        playerAdded = false;
        for (let y = 0; y < gridHeight; y++) {
            for (let x = 0; x < gridWidth; x++) {
                grid[y][x] = 0;
            }
        }
        return;
    }

    // move the character around
    for (let y = 0; y < gridHeight; y++) {
        for (let x = 0; x < gridWidth; x++) {
            if (grid[y][x] === 3) {
                if ((e.key === 'ArrowLeft' || e.key === 'a') && x > 0 && grid[y][x - 1] === 0) {
                    grid[y][x] = 0;
                    grid[y][x - 1] = 3;
                    return;
                } else if ((e.key === 'ArrowRight' || e.key === 'd') && x < gridWidth - 1 && grid[y][x + 1] === 0) {
                    grid[y][x] = 0;
                    grid[y][x + 1] = 3;
                    return;
                } else if (isJumpKey(e.key) && y < gridHeight - 1 && grid[y + 1][x] !== 0) {
                    jumpPlayer(y, x);
                    return;
                }
            }
        }
    }
});

const jumpHeight = 10;

const isJumpKey = key => {
    return key === ' ' || key === 'ArrowUp' || key === 'w';
}

const jumpPlayer = (y, x) => {
    grid[y][x] = 0;
    grid[Math.max(y - jumpHeight, 0)][x] = 3;
}

const updateGrid = () => {
    for (let y = gridHeight - 2; y >= 0; y--) {
        for (let x = 0; x < gridWidth; x++) {
            if (grid[y][x] === 1) {
                if (grid[y + 1][x] === 0) {
                    grid[y][x] = 0;
                    grid[y + 1][x] = 1;
                } else if (x > 0 && grid[y + 1][x - 1] === 0) {
                    grid[y][x] = 0;
                    grid[y + 1][x - 1] = 1;
                } else if (x < gridWidth - 1 && grid[y + 1][x + 1] === 0) {
                    grid[y][x] = 0;
                    grid[y + 1][x + 1] = 1;
                }
            } else if (grid[y][x] === 3) {
                if (y < gridHeight - 1 && grid[y + 1][x] === 0) {
                    grid[y][x] = 0;
                    grid[y + 1][x] = 3;
                }
            }
        }
    }
};

const drawGrid = () => {
    // clear the canvas
    ctx.fillStyle = 'beige';
    ctx.fillRect(0, 0, canvas.width, canvas.height);

    // draw the sand and player
    ctx.fillStyle = 'black';
    for (let y = 0; y < gridHeight; y++) {
        for (let x = 0; x < gridWidth; x++) {
            if (grid[y][x] === 1) {
                ctx.fillRect(x * gridSize, y * gridSize, gridSize, gridSize);
            } else if (grid[y][x] === 3) {
                ctx.fillStyle = 'red';
                ctx.fillRect(x * gridSize, y * gridSize, gridSize, gridSize);
                ctx.fillStyle = 'black'; // Reset fill color to black after drawing the player
            }
        }
    }
};

const framerate = 60;
let lastFrameTime = 0;

const gameLoop = (currentTime) => {
    const deltaTime = (currentTime - lastFrameTime) / 1000;
    if (deltaTime > 1 / framerate) {
        lastFrameTime = currentTime;
        updateGrid();
        drawGrid();
    }
    requestAnimationFrame(gameLoop);
};

requestAnimationFrame(gameLoop);

function addSand(e) {
    const rect = canvas.getBoundingClientRect();
    const x = Math.floor((e.clientX - rect.left) / gridSize);
    const y = Math.floor((e.clientY - rect.top) / gridSize);
    if (x >= 0 && x < gridWidth && y >= 0 && y < gridHeight) {
        grid[y][x] = 1;
    }
}

function addPlayer() {
    for (let y = 0; y < gridHeight; y++) {
        for (let x = 0; x < gridWidth; x++) {
            if (grid[y][x] === 1) {
                grid[Math.max(0, y - 10)][x] = 3;
                return;
            }
        }
    }
}