///////////////////////////////////////////////////////////////
// Picture Fade
///////////////////////////////////////////////////////////////
// (c) 2009 by Dominik Scholz, go4u.de Webdesign
// visit: http://www.go4u.de
///////////////////////////////////////////////////////////////

// Settings //
var fade_distance = 5;
var fade_delay = 50;
var fade_slide = 2;
var fade_numbers = 2;
var fade_path = 'images/slideshow/';

// Initialising //
var pic_number = 1;
var opacity = 5;
var opacity_dec = true;

function picslide()
{
	var container = document.getElementById('slideshow');
	var pic;

	if (opacity_dec)
		pic = container.getElementsByTagName('img')[1];
	else
		pic = container.getElementsByTagName('img')[0];

    pic.style.left = ((parseInt(pic.style.left)||0)-fade_slide)+'px';

	if (parseInt(pic.style.left) + pic.offsetWidth < container.offsetWidth + fade_slide)
	{
		if (opacity_dec)
			container.getElementsByTagName('img')[0].style.left = '0px';
		else
			container.getElementsByTagName('img')[1].style.left = '0px';
	    window.setTimeout('picfade();', fade_delay);
	}
	else	
	    window.setTimeout('picslide();', fade_delay);
}

function picfade()
{
	var container = document.getElementById('slideshow');
	var pic1 = container.getElementsByTagName('img')[1];
	var pic2 = container.getElementsByTagName('img')[0];


    if (opacity_dec)
    {
        if (opacity == 0)
        {
            pic_number = (pic_number < fade_numbers)? (pic_number+1):1;
            pic1.src = fade_path+pic_number+'.jpg';
            opacity_dec = false;
		    window.setTimeout('picslide();', fade_delay);
        }
        else
        {
            opacity = opacity - fade_distance;
            set_opacity(pic1.style, opacity);
		    window.setTimeout('picfade();', fade_delay);
        }
    }
    else
    {
        if (opacity == 100)
        {
            pic_number = (pic_number < fade_numbers)? (pic_number+1):1;
            pic2.src = fade_path+pic_number+'.jpg';
            opacity_dec = true;
		    window.setTimeout('picslide();', fade_delay);
        }
        else
        {
            opacity = opacity + fade_distance;
            set_opacity(pic1.style, opacity);
		    window.setTimeout('picfade();', fade_delay);
        }
    }

}

function set_opacity(obj, percentage)
{
	var n_percent = Math.ceil(percentage);
    obj.filter="Alpha(opacity="+n_percent+")";
    obj.MozOpacity=""+n_percent/100;
    obj.KTHMLOpacity=""+n_percent/100;
    obj.opacity=""+n_percent/100;
}


function picfade_start()
{
	var container = document.getElementById('slideshow');

    pic_number = 1;

    container.getElementsByTagName('img')[0].src = fade_path+pic_number+'.jpg';
    container.getElementsByTagName('img')[1].src = fade_path+pic_number+'.jpg';

	picfade();
}