Embed

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Snake Game</title>
  <style>
    /* Basic styling for the canvas */
    body { display: flex; justify-content: center; align-items: center; height: 100vh; margin: 0; background: #f0f0f0; }
    canvas { background: #fff; border: 2px solid #000; }
  </style>
</head>
<body>
  <canvas id="game" width="400" height="400"></canvas>
  <script>
    const canvas = document.getElementById("game");
    const ctx = canvas.getContext("2d");

    const grid = 20; // size of each cell
    let count = 0; // frame counter for speed control

    // Snake object definition
    let snake = {
      x: 160,
      y: 160,
      dx: grid,
      dy: 0,
      cells: [],
      maxCells: 4
    };

    // Apple position
    let apple = {
      x: 320,
      y: 320
    };

    // Helper function to get a random number within a range (multiple of grid)
    function getRandomInt(min, max) {
      return Math.floor(Math.random() * (max - min)) + min;
    }

    // Main game loop
    function gameLoop() {
      requestAnimationFrame(gameLoop);
      // Slow game loop to 15 fps by using a counter
      if (++count < 4) {
        return;
      }
      count = 0;
      ctx.clearRect(0, 0, canvas.width, canvas.height);

      // Move snake by updating its position
      snake.x += snake.dx;
      snake.y += snake.dy;

      // Wrap snake position horizontally on edge of screen
      if (snake.x < 0) {
        snake.x = canvas.width - grid;
      } else if (snake.x >= canvas.width) {
        snake.x = 0;
      }

      // Wrap snake position vertically on edge of screen
      if (snake.y < 0) {
        snake.y = canvas.height - grid;
      } else if (snake.y >= canvas.height) {
        snake.y = 0;
      }

      // Add new head position to the snake's body
      snake.cells.unshift({ x: snake.x, y: snake.y });

      // Remove cells as we move away to maintain the snake's length
      if (snake.cells.length > snake.maxCells) {
        snake.cells.pop();
      }

      // Draw the apple
      ctx.fillStyle = "red";
      ctx.fillRect(apple.x, apple.y, grid - 1, grid - 1);

      // Draw the snake and check for collisions
      ctx.fillStyle = "green";
      snake.cells.forEach(function(cell, index) {
        ctx.fillRect(cell.x, cell.y, grid - 1, grid - 1);

        // Check if snake eats the apple
        if (cell.x === apple.x && cell.y === apple.y) {
          snake.maxCells++;
          // Place the apple randomly on the grid
          apple.x = getRandomInt(0, canvas.width / grid) * grid;
          apple.y = getRandomInt(0, canvas.height / grid) * grid;
        }

        // Check for collision with self, starting at index 1 to skip the head
        for (let i = index + 1; i < snake.cells.length; i++) {
          if (cell.x === snake.cells[i].x && cell.y === snake.cells[i].y) {
            // Reset snake on collision
            snake.x = 160;
            snake.y = 160;
            snake.cells = [];
            snake.maxCells = 4;
            snake.dx = grid;
            snake.dy = 0;
            // Reposition the apple
            apple.x = getRandomInt(0, canvas.width / grid) * grid;
            apple.y = getRandomInt(0, canvas.height / grid) * grid;
          }
        }
      });
    }

    // Listen to keyboard events to move the snake
    document.addEventListener("keydown", function(e) {
      // Left arrow key
      if (e.which === 37 && snake.dx === 0) {
        snake.dx = -grid;
        snake.dy = 0;
      }
      // Up arrow key
      else if (e.which === 38 && snake.dy === 0) {
        snake.dy = -grid;
        snake.dx = 0;
      }
      // Right arrow key
      else if (e.which === 39 && snake.dx === 0) {
        snake.dx = grid;
        snake.dy = 0;
      }
      // Down arrow key
      else if (e.which === 40 && snake.dy === 0) {
        snake.dy = grid;
        snake.dx = 0;
      }
    });

    // Start the game loop
    requestAnimationFrame(gameLoop);
  </script>
</body>
</html>
