var conf_reflection_p = 0.5;
var conf_focus = 4;
var conf_slider_width = 14;
var conf_images_cursor = 'pointer';
var conf_slider_cursor = 'default';
var conf_imageflow = 'if';
var conf_loading = 'loading';
var conf_images = 'images';
var conf_captions = 'captions';
var conf_scrollbar = 'scrollbar';
var conf_slider = 'slider';
var caption_id = 0;
var new_caption_id = 0;
var current = 0;
var target = 0;
var mem_target = 0;
var timer = 0;
var array_images = new Array();
var new_slider_pos = 0;
var dragging = false;
var dragobject = null;
var dragx = 0;
var posx = 0;
var new_posx = 0;
var xstep = 150;

function step()
{
    switch (target < current-1 || target > current+1)
    {
        case true:
            moveTo(current + (target-current)/3);
            window.setTimeout(step, 50);
            timer = 1;
            break;
        default:
            timer = 0;
            break;
    }
}

function glideTo(x, new_caption_id)
{
    target = x;
    mem_target = x;
    if (timer == 0)
    {
        window.setTimeout(step, 50);
        timer = 1;
    }
    caption_id = new_caption_id;

    var cm_titel = '';
    var cm_bild  = '';
    var cm_text  = '';
    var cm_link  = '';

    var cm_title = img_div.childNodes.item(array_images[caption_id]).getAttribute('title');
    if(cm_title != '#' && cm_title != '')
    {
       cm_titel = cm_title + '<br><br>';
    }

    var cm_alt = img_div.childNodes.item(array_images[caption_id]).getAttribute('alt');
    if(cm_alt != '#' && cm_alt != '')
    {
       cm_bild = '<a rel="facebox" target="_blank" href="' + cm_alt + '">Vorschau vergr&ouml;&szlig;ern</a> | '
    }

    var cm_name = img_div.childNodes.item(array_images[caption_id]).getAttribute('name');
    if(cm_name != '#' && cm_name != '')
    {
       cm_text = '<a rel="facebox" href="#' + cm_name + '">Informationen anzeigen</a>  | ';
    }

    var cm_longdesc = img_div.childNodes.item(array_images[caption_id]).getAttribute('longdesc');
    if(cm_longdesc != '#' && cm_longdesc != '')
    {
       cm_link = '<a target="_blank" href="' + cm_longdesc + '">Website besuchen</a> | ';
    }


    caption = cm_titel + ' | ' + cm_bild + cm_text + cm_link;
    if (caption == '')
    {
        caption = '&nbsp;';
    }
    caption_div.innerHTML = caption;
    jQuery(document).ready(function($) { $('a[rel*=facebox]').facebox() })
    if (dragging == false)
    {
        new_slider_pos = (scrollbar_width * (-(x*100/((max-1)*xstep))) / 100) - new_posx;
        slider_div.style.marginLeft = (new_slider_pos - conf_slider_width) + 'px';
    }
}

function moveTo(x)
{
    current = x;
    var zIndex = max;

    for (var index = 0; index < max; index++)
    {
        var image = img_div.childNodes.item(array_images[index]);
        var current_image = index * -xstep;
        if ((current_image+max_conf_focus) < mem_target || (current_image-max_conf_focus) > mem_target)
        {
            image.style.visibility = 'hidden';
            image.style.display = 'none';
        }
        else
        {
            var z = Math.sqrt(10000 + x * x) + 100;
            var xs = x / z * size + size;
            image.style.display = 'block';
            var new_img_h = (image.h / image.w * image.pc) / z * size;
            switch ( new_img_h > max_height )
            {
                case false:
                    var new_img_w = image.pc / z * size;
                    break;
                default:
                    new_img_h = max_height;
                    var new_img_w = image.w * new_img_h / image.h;
                    break;
            }

            var new_img_top = (images_width * 0.34 - new_img_h) + images_top + ((new_img_h / (conf_reflection_p + 1)) * conf_reflection_p) - 100;
            image.style.left = xs - (image.pc / 2) / z * size + images_left + 'px';
            image.style.height = new_img_h  + 'px';
            image.style.width = new_img_w + 'px';
            image.style.top = new_img_top + 'px';
            image.style.visibility = 'visible';

            switch ( x < 0 )
            {
                case true:
                    zIndex++;
                    break;
                default:
                    zIndex = zIndex - 1;
                    break;
            }
            switch ( image.i == caption_id )
            {
                case false:
                    image.id = '';
                    image.onclick = function() { glideTo(this.x_pos, this.i); }
                    //image.style.cursor = conf_images_cursor;
                    break;
                default:
                    zIndex = zIndex + 1;
                    image.onclick = function() { jQuery.facebox('<img src="' + img_div.childNodes.item(array_images[caption_id]).getAttribute('alt') + '">'); }
                    //image.style.cursor = '';
                    break;
            }
            image.style.zIndex = zIndex;
        }
        x += xstep;
    }
}

function refresh(onload)
{
    imageflow_div = document.getElementById(conf_imageflow);
    img_div = document.getElementById(conf_images);
    scrollbar_div = document.getElementById(conf_scrollbar);
    slider_div = document.getElementById(conf_slider);
    caption_div = document.getElementById(conf_captions);
    images_width = img_div.offsetWidth;
    images_top = imageflow_div.offsetTop;
    images_left = imageflow_div.offsetLeft;
    max_conf_focus = conf_focus * xstep;
    size = images_width * 0.5;
    scrollbar_width = images_width * 0.6;
    conf_slider_width = conf_slider_width * 0.5;
    max_height = images_width * 0.51;
    imageflow_div.style.height = max_height + 'px';
    img_div.style.height = images_width * 0.338 + 'px';
    caption_div.style.width = images_width + 'px';
    caption_div.style.marginTop = images_width * 0.03 + 'px';
    scrollbar_div.style.marginTop = images_width * 0.02 + 'px';
    scrollbar_div.style.marginLeft = images_width * 0.2 + 'px';
    scrollbar_div.style.width = scrollbar_width + 'px';
    slider_div.onmousedown = function () { dragstart(this); };
    slider_div.style.cursor = conf_slider_cursor;
    max = img_div.childNodes.length;
    var i = 0;
    for (var index = 0; index < max; index++)
    {
        var image = img_div.childNodes.item(index);
        if (image.nodeType == 1)
        {
            array_images[i] = index;
            image.onclick = function() { glideTo(this.x_pos, this.i); }
            image.x_pos = (-i * xstep);
            image.i = i;
            if(onload == true)
            {
                image.w = image.width;
                image.h = image.height;
            }
            switch ((image.w + 1) > (image.h / (conf_reflection_p + 1)))
            {
                case true:
                    image.pc = 118;
                    break;
                default:
                    image.pc = 100;
                    break;
            }
            image.url = img_div.childNodes.item(array_images[caption_id]).getAttribute('src');
            // image.ondblclick = function() { }
            image.style.cursor = conf_images_cursor;
            i++;
        }
    }
    max = array_images.length;
    moveTo(current);
    glideTo(current, caption_id);
}

function show(id)
{
    var element = document.getElementById(id);
    element.style.visibility = 'visible';
}

function hide(id)
{
    var element = document.getElementById(id);
    element.style.visibility = 'hidden';
    element.style.display = 'none';
}

window.onload = function()
{
    if(document.getElementById(conf_imageflow))
    {
        hide(conf_loading);
        refresh(true);
        show(conf_images);
        show(conf_scrollbar);
        /*initMouseWheel();*/
        initMouseDrag();
    }
}

/*
window.onresize = function()
{
    if(document.getElementById(conf_imageflow))
    {
        refresh();
    }
}
*/

function handle(delta)
{
    var change = false;
    switch (delta > 0)
    {
        case true:
            if(caption_id >= 1)
            {
                target = target + xstep;
                new_caption_id = caption_id - 1;
                change = true;
            }
            break;
        default:
            if(caption_id < (max-1))
            {
                target = target - xstep;
                new_caption_id = caption_id + 1;
                change = true;
            }
            break;
    }
    if (change == true)
    {
        glideTo(target, new_caption_id);
    }
}

function wheel(event)
{
    var delta = 0;
    if (!event)
    {
        event = window.event;
    }
    if (event.wheelDelta)
    {
        delta = event.wheelDelta / 120;
    }
    else if (event.detail)
    {
        delta = -event.detail / 3;
    }
    if (delta)
    {
        handle(delta);
    }
    if (event.preventDefault)
    {
        event.preventDefault();
    }
    event.returnValue = false;
}

function initMouseWheel()
{
    if(window.addEventListener)
    {
        imageflow_div.addEventListener('DOMMouseScroll', wheel, false);
    }
    imageflow_div.onmousewheel = wheel;
}

function dragstart(element)
{
    dragobject = element;
    dragx = posx - dragobject.offsetLeft + new_slider_pos;
}

function dragstop()
{
    dragobject = null;
    dragging = false;
}

function drag(e)
{
    posx = document.all ? window.event.clientX : e.pageX;
    if(dragobject != null)
    {
        dragging = true;
        new_posx = (posx - dragx) + conf_slider_width;
        if(new_posx < ( - new_slider_pos))
        {
            new_posx = - new_slider_pos;
        }
        if(new_posx > (scrollbar_width - new_slider_pos))
        {
            new_posx = scrollbar_width - new_slider_pos;
        }
        var slider_pos = (new_posx + new_slider_pos);
        var step_width = slider_pos / ((scrollbar_width) / (max-1));
        var image_number = Math.round(step_width);
        var new_target = (image_number) * -xstep;
        var new_caption_id = image_number;
        dragobject.style.left = new_posx + "px";
        glideTo(new_target, new_caption_id);
    }
}

function initMouseDrag()
{
    document.onmousemove = drag;
    document.onmouseup = dragstop;
}

function getKeyCode(event)
{
    event = event || window.event;
    return event.keyCode;
}

document.onkeydown = function(event)
{
    var charCode  = getKeyCode(event);
    switch (charCode)
    {
        case 39:
            handle(-1);
            break;
        case 37:
            handle(1);
            break;
    }
}