/* Configuration variables */
var conf_reflection_p = 0.5;         // Sets the height of the reflection in % of the source image
var conf_focus = 4;                  // Sets the numbers of images on each side of the focussed one
var conf_slider_width = 14;          // Sets the px width of the slider div
var conf_images_cursor = 'pointer';  // Sets the cursor type for all images default is 'default'
var conf_slider_cursor = 'e-resize'; // Sets the slider cursor type: try "e-resize" default is 'default'

/* Id names used in the HTML */
var conf_imageflow = 'imageflow';    // Default is 'imageflow'
var conf_loading = 'loading';        // Default is 'loading'
var conf_images = 'images';          // Default is 'images'
var conf_captions = 'captions';      // Default is 'captions'
var conf_scrollbar = 'scrollbar';    // Default is 'scrollbar'
var conf_slider = 'slider';          // Default is 'slider'
var conf_slideshow = 'slideshow';    // Default is 'slideshow'
var conf_youtube = 'youtubepopup';   // Default is 'slideshow'

/* Define global variables */
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 = [];
var new_slider_pos = 0;
var dragging = false;
var dragobject = null;
var dragx = 0;
var posx = 0;
var new_posx = 0;
var xstep = 150;
var slide = null;
var sizeAlgo = 0;	// 0 = default, 1 = small to big
var glidetopicture = 0;
var slideshowtime = 3000;
var slideshowbutton = true;
var slideshowauto = true;
var videowidht  = '425';
var videoheight = '350';
var videotop  = '-350px';
var videoleft = '-30px';
var output = "";

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 slideshow(i){
	var len = img_div.childNodes.length;
    var max = 0;
    for(i=0; i<len; i++){
        if(img_div.childNodes.item(i).nodeType==1)
            max++;
    }
	if( caption_id == max - 1)
	{
	   target == 0;
	   glideTo( 0 , 0 );
	   slide = window.setTimeout('slideshow(1)', slideshowtime );
	}
	else
	{
	   handle(-1);
	   i = i+1;
	   slide = window.setTimeout('slideshow('+i+')', slideshowtime );
	}
    slideshow_div.style.display='none';
}

function stopslideshow(){
    slideshow_div.style.display='block';
	window.clearTimeout(slide);
}

function glideTo(x, new_caption_id)
{
	/* Animate gliding to new x position */
	target = x;
	mem_target = x;
	if (timer == 0)
	{
		window.setTimeout(step, 50);
		timer = 1;
	}

    if (max == 0)
    {
        hide(conf_loading);
		hide(conf_scrollbar);
		hide(conf_slideshow);
    }
    else
    {

	/* Display new caption */
	caption_id = new_caption_id;
	caption = img_div.childNodes.item(array_images[caption_id]).getAttribute('alt');
	if (caption == '') caption = '&nbsp;';
	caption_div.innerHTML = caption;
	}

	/* Set scrollbar slider to new position */
	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;

	/* Main loop */
	for (var index = 0; index < max; index++)
	{
		var image = img_div.childNodes.item(array_images[index]);
		var current_image = index * -xstep;

		/* Don't display images that are not conf_conf_focussed */
		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 xs;
			switch(sizeAlgo)
			{
			default:
			var z = Math.sqrt(10000 + x * x) + 100;
				xs = x / z * size + size;
				break;
			case 1:
				var sgn_x = (x > 0) ? 1 : -1; var z = 150 + Math.pow(Math.abs(x), 0.8);
				xs = sgn_x * Math.pow(Math.abs(x), 0.8) + size;
				break;
			}

			/* Still hide images until they are processed, but set display style to block */
			image.style.display = 'block';

			/* Process new image height and image width */
			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);

			/* Set new image properties */
			image.style.left = xs - (image.pc / 2) / z * size + images_left + 'px';
			if(new_img_w && new_img_h)
			{
				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';

			/* Set image layer through zIndex */
			switch ( x < 0 )
			{
				case true:
					zIndex++;
					break;

				default:
					zIndex = zIndex - 1;
					break;
			}

			/* Change zIndex and onclick function of the focussed image and stop slideshow */
			switch ( image.i == caption_id )
			{
				case false:
					image.onclick = function()
					{
                        stopslideshow();

                    glideTo(this.x_pos, this.i);

					};
					break;

				default:
					zIndex = zIndex + 1;

                    if(max == image.i + 1 && document.getElementById('imfl_next') != null &&  document.getElementById('imfl_next') != 'undefined' && document.getElementById('imfl_next') != undefined){

                    image.onclick = function() { document.location = this.url; };
					break;

					  }else if(image.i == 0 && document.getElementById('imfl_previous') != null &&  document.getElementById('imfl_previous') != 'undefined' && document.getElementById('imfl_previous') != undefined){

                    image.onclick = function() { document.location = this.url; };
					break;

	                  }else{

	                    switch (output)
	                    {
	                      case "highslide" :
	                         image.onclick = function() { return hs.expand(this, { src: this.getAttribute('longdesc') }); };
	                         break;
	                      case "video" :
	                         image.onclick = function() { playVid(this.url); };
	                         break;
	                      default :
	                         image.onclick = function() { document.location = this.url; };
	                         break;
	                    }
                      }
			}
			image.style.zIndex = zIndex;
		}
		x += xstep;
	}
}

/* Main function */
function refresh(onload)
{
	/* Cache document objects in global variables */
	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);
	slideshow_div = document.getElementById(conf_slideshow);
	youtube_div = document.getElementById(conf_youtube);

	/* Cache global variables, that only change on refresh */
	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;

	/* Change imageflow div properties */
	imageflow_div.style.height = max_height + 'px';

	/* Change images div properties */
	img_div.style.height = images_width * 0.338 + 'px';

	/* Change captions div properties */
	caption_div.style.width = images_width + 'px';
	caption_div.style.marginTop = images_width * 0.03 + 'px';

	/* Change scrollbar div properties */
	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';

	/* Set slider attributes */
    slider_div.onmousedown = function () { dragstart(this); return false; };
	slider_div.style.cursor = conf_slider_cursor;

	/* Cache EVERYTHING! */
	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;

			/* Set image onclick by adding i and x_pos as attributes! */
			image.onclick = function() { glideTo(this.x_pos, this.i); };
			image.x_pos = (-i * xstep);
			image.i = i;

			/* Add width and height as attributes ONLY once onload */
			if(onload == true)
			{
				image.w = image.width;
				image.h = image.height;
			}

			/* Check source image format. Get image height minus reflection height! */
			switch ((image.w + 1) > (image.h / (conf_reflection_p + 1)))
			{
				/* Landscape format */
				case true:
					image.pc = 118;
					break;

				/* Portrait and square format */
				default:
					image.pc = 100;
					break;
			}

			/* Set ondblclick event */
			image.url = image.getAttribute('longdesc');
			//image.ondblclick = function() { document.location = this.url; }

			/* Set image cursor type */
			image.style.cursor = conf_images_cursor;

			i++;
		}
	}
	max = array_images.length;

	/* Display images in current order */
	moveTo(current);
	glideTo(current, caption_id);
}

/* Show/hide element functions */
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';
}

/* Hide loading bar, show content and initialize mouse event listening after loading */
function startimageflow()
{
	if(document.getElementById(conf_imageflow))
	{
		hide(conf_loading);
		refresh(true);
		show(conf_images);
		show(conf_scrollbar);
        if (slideshowbutton)
        {
        	show(conf_slideshow);
        }
		initMouseWheel();
		initMouseDrag();
        if (glidetopicture == 0)
        {
			moveTo(5000);
        }
        if (max < glidetopicture)
        {
			moveTo(5000);
        }else{
			glideTo(-glidetopicture * 150,glidetopicture);
		}
        if (slideshowauto && max > 1)
        {
			slideshow(1);
		}
	}
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload !== 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      if (oldonload) {
        oldonload();
      }
      func();
    };
  }
}

addLoadEvent(startimageflow);

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

if(navigator.userAgent.search(/msie/i)!== -1) {
	// nothing !!
	} else {
/* Fixes the back button issue */
window.onunload = function()
{
  document = null;
	};
}


/* Handle the wheel angle change (delta) of the mouse wheel */
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;
	}

	/* Glide to next (mouse wheel down) / previous (mouse wheel up) image */
	if (change == true)
	{
		glideTo(target, new_caption_id);
	}
}

/* Event handler for mouse wheel event */
function wheel_imageflow(event)
{
	var delta = 0;
	if (!event) { event = window.event;
	}
	if (event.wheelDelta)
	{
     	    stopslideshow();

        delta = event.wheelDelta / 120;
	}
	else if (event.detail)
	{
     		stopslideshow();

		delta = -event.detail / 3;
	}
	if (delta) { handle(delta);
	}
	if (event.preventDefault) { event.preventDefault();
	}
	event.returnValue = false;
}

/* Initialize mouse wheel event listener */
function initMouseWheel()
{
	if(window.addEventListener) { imageflow_div.addEventListener('DOMMouseScroll', wheel_imageflow, false);
	}
	imageflow_div.onmousewheel = wheel_imageflow;
}

/* This function is called to drag an object (= slider div) */
function dragstart(element)
{
	dragobject = element;
	dragx = posx - dragobject.offsetLeft + new_slider_pos;
}

/* This function is called to stop dragging an object */
function dragstop()
{
	dragobject = null;
	dragging = false;
}

/* This function is called on mouse movement and moves an object (= slider div) on user action */
function drag(e)
{
	posx = document.all ? window.event.clientX : e.pageX;
	if(dragobject != null)
	{
		dragging = true;

     	stopslideshow();

		new_posx = (posx - dragx) + conf_slider_width;

		/* Make sure, that the slider is moved in proper relation to previous movements by the glideTo function */
		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);
	}
}

/* Initialize mouse event listener */
function initMouseDrag()
{
	document.onmousemove = drag;
	document.onmouseup = dragstop;

	/* Avoid text and image selection while dragging  */
	document.onselectstart = function ()
	{
		if (dragging == true)
		{
			return false;
		}
		else
		{
			return true;
		}
	};
}

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

document.onkeydown = function(event)
{
	var charCode  = getKeyCode(event);
	switch (charCode)
	{
		/* Right arrow key */
		case 39:
			handle(-1);
			stopslideshow();
			break;

		/* Left arrow key */
		case 37:
			handle(1);
			stopslideshow();
			break;
	}
};

function playVid(vidId)
{
  if (youtube_div.style.display=='block')
  {
     youtube_div.style.display='none';
     youtube_div.innerHTML='';
  	}
  	else
  	{
     	stopslideshow();

     youtube_div.style.display='block';
	 youtube_div.style.top = ''+videotop+'';
	 youtube_div.style.left = ''+videoleft+'';
     youtube_div.innerHTML='<a href="javascript:playVid()" style="margin: 4px; text-decoration:none;">Close</a>';
     var vidstring ='<center><embed enablejavascript="false" allowScriptAccess="never"';
     vidstring+=' allownetworking="internal" type="application/x-shockwave-flash" allowfullscreen="true"';
     vidstring+=' src="'+vidId+'" ';
     vidstring+=' wmode="transparent" height="'+videoheight+'" width="'+videowidht+'"></center>';
     youtube_div.innerHTML+=vidstring;
  }
}

function moveHandler(e)
{
  if (e == null)
  {
  	e = window.event
  }
  if (e.button<=1&&dragOK)
  {
     selObj.style.left=e.clientX-dragXoffset+'px';
     selObj.style.top=e.clientY-dragYoffset+'px';
     return false;
  }
}

function cleanup(e)
{
	document.onmousemove=null;
	document.onmouseup=null;
	selObj.style.cursor=orgCursor;
	dragOK=false;
}

function dragHandler(e)
{
  var htype='-moz-grabbing';
	  if (e == null)
	  {
	  e = window.event; htype='move';
	  }
	      var target = e.target != null ? e.target : e.srcElement;
	      selObj=target;
	      orgCursor=target.style.cursor;

	  if (target.className=="vidFrame" || target.className=="youtubemoveable")
	  {
	     target.style.cursor=htype;
	     dragOK=true;
	     dragXoffset=e.clientX-parseInt(selObj.style.left);
	     dragYoffset=e.clientY-parseInt(selObj.style.top);
	     document.onmousemove=moveHandler;
	     document.onmouseup=cleanup;
	     return false;
	  }
}

document.onmousedown=dragHandler;