Snake code

//The direction the snake is traveling
var current_direction = 'right';

//The snake array
var snake = [[10,4], [10,3], [10,2], [10,1]];

//The score
var score = 0;

//Is the game currently playing
var active = true;

var t = null;
var speed = 250;

function move_snake()
{
    for(var i = snake.length - 1; i >= 0; i--)
    {
        //Handle the head
        if(i == 0)
        {
            if(current_direction == 'up')
            {
                snake[0][0]--;
                //current_direction = 'up';
            }
            else if(current_direction == 'down')
            {
                snake[0][0]++;
                //current_direction = 'down';
            }
            else if(current_direction == 'left')
            {
                snake[0][1]--;
                //current_direction = 'left';
            }
            else if(current_direction == 'right')
            {
                snake[0][1]++;
                //current_direction = 'right';
            }

            //Make sure we're within the boundaries
            if(snake[0][1] < 0 ||
               snake[0][1] > 24 ||
               snake[0][0] < 0 ||
               snake[0][0] > 14)
            {
                active = false;
                alert('You died with a score of ' + score);
                return;
            }

            //Check if we ate a piece of food
            if($('#c' + snake[0][0] + '-' + snake[0][1]).find('img').attr('src').indexOf('food') != -1)
            {
                generate_food(snake[0][0], snake[0][1]);
                snake.push([snake[snake.length - 1][0], snake[snake.length - 1][1]]);
                score += 10;
                $('#score').html('Score: ' + score);
            }

            //Check if we hit ourselves
            if($('#c' + snake[0][0] + '-' + snake[0][1]).find('img').attr('src').indexOf('snake') != -1)
            {
                active = false;
                alert('You died with a score of ' + score);
                return;
            }

            //Move the head
            $('#c' + snake[i][0] + '-' + snake[i][1]).find('img').attr('src', 'images/snake.gif');
        }
        else
        {
            if(i == (snake.length - 1))
            {
                $('#c' + snake[i][0] + '-' + snake[i][1]).find('img').attr('src', 'images/empty.gif');
            }

            snake[i][0] = snake[i - 1][0];
            snake[i][1] = snake[i - 1][1];
        }
    }

    if(active)
    {
        t = setTimeout(move_snake, speed);
    }
}

function generate_food(x, y)
{
    var food_x = Math.round(Math.random() * 14);
    var food_y = Math.round(Math.random() * 24);

    //Ensure we don't generate a piece of food on the snake or the same place as the food that was just eaten
    while($('#c' + food_x + '-' + food_y).find('img').attr('src').indexOf('snake') != -1 || (food_x == x && food_y == y))
    {
        food_x = Math.round(Math.random() * 14);
        food_y = Math.round(Math.random() * 24);
    }

    $('#c' + food_x + '-' + food_y).find('img').attr('src', 'images/food.gif');
}

function setup()
{
    $(window).keydown(function(e)
    {
        if(e.keyCode == 38 && current_direction != 'down' && current_direction != 'up')
        {
            current_direction = 'up';
            clearTimeout(t);
            move_snake();
        }
        else if(e.keyCode == 40 && current_direction != 'up')
        {
            current_direction = 'down';
            clearTimeout(t);
            move_snake();
        }
        else if (e.keyCode == 37 && current_direction != 'right')
        {
            current_direction = 'left';
            clearTimeout(t);
            move_snake();
        }
        else if (e.keyCode == 39 && current_direction != 'left')
        {
            current_direction = 'right';
            clearTimeout(t);
            move_snake();
        }
    });

    t = setTimeout(move_snake, speed);
}