/* note: requires gallery_images.js for the images list to parse for all functions. */
images = [];

function display_gallery(image_dir)
{
    if (image_dir.charAt(image_dir.length - 1) != "/")
        image_dir += "/";

    for (var i = 0; i < images.length; i++)
    {
        var a = document.getElementById('image' + (i + 1));
        a.href = "image?id=" + images[i].name;
        
        var thumb = document.createElement('img');
        thumb.src = image_dir + get_thumb_name(images[i].name);
        
        a.appendChild(thumb);
    }
}

function get_thumb_name(img) 
{
    var parts = img.split('.', 2);
    var new_image = parts[0] + "_th." + parts[1];
    
    return new_image;
}

/* Retrieve current image to display and the next and previous images. */
function getImage(image_name)
{
    var prev = "";
    var next = "";
    var curr = "";
    
    for(var i = 0; i < images.length; i++)    
    {
        if (image_name == images[i].name)
        {
            if (i - 1 >= 0) prev = images[i-1].name;
            if (i + 1 < images.length) next = images[i+1].name;
            curr = images[i];
            break;
        }
    }
    
    if (curr == "")
        return -1;
    return {'name': curr.name, 'title': curr.title, 'prev': prev, 'next': next};
}

/* Set the gallery image to display */
function setImage(image_name, image_dir)
{
    var img = getImage(image_name);

    if (image_dir.charAt(image_dir.length - 1) != "/")
        image_dir += "/";

    if (img == -1) 
    {
        window.location = 'gallery.php';
        exit();
    }
    var img_elem = document.getElementById('displayed');
    var img_caption = document.getElementById('caption');
    
    var prev = document.getElementById('prev_link');
    var next = document.getElementById('next_link');
    
    img_elem.src = image_dir + img.name;
    img_caption.innerHTML = img.title;
    
    if (img.prev != "")
        prev.href = 'image?id=' + img.prev;
    if (img.next != "")
        next.href = 'image?id=' + img.next;
}