/* DHTML-Bibliothek */

var DHTML = false, DOM = false, MSIE4 = false, NS4 = false, OP = false;

if (document.getElementById) {
  DHTML = true;
  DOM = true;
} else {
  if (document.all) {
    DHTML = true;
    MSIE4 = true;
  } else {
    if (document.layers) {
      DHTML = true;
      NS4 = true;
    }
  }
}
if (window.opera) {
  OP = true;
}

function getElement (Mode, Identifier, ElementNumber) {
  var Element, ElementList;
  if (DOM) {
    if (Mode.toLowerCase() == "id") {
      Element = document.getElementById(Identifier);
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    if (Mode.toLowerCase() == "name") {
      ElementList = document.getElementsByName(Identifier);
      Element = ElementList[ElementNumber];
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    if (Mode.toLowerCase() == "tagname") {
      ElementList = document.getElementsByTagName(Identifier);
      Element = ElementList[ElementNumber];
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    return false;
  }
  if (MSIE4) {
    if (Mode.toLowerCase() == "id" || Mode.toLowerCase() == "name") {
      Element = document.all(Identifier);
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    if (Mode.toLowerCase() == "tagname") {
      ElementList = document.all.tags(Identifier);
      Element = ElementList[ElementNumber];
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    return false;
  }
  if (NS4) {
    if (Mode.toLowerCase() == "id" || Mode.toLowerCase() == "name") {
      Element = document[Identifier];
      if (!Element) {
        Element = document.anchors[Identifier];
      }
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    if (Mode.toLowerCase() == "layerindex") {
      Element = document.layers[Identifier];
      if (!Element) {
        Element = false;
      }
      return Element;
    }
    return false;
  }
  return false;
}

function getAttribute (Mode, Identifier, ElementNumber, AttributeName) {
  var Attribute;
  var Element = getElement(Mode, Identifier, ElementNumber);
  if (!Element) {
    return false;
  }
  if (DOM || MSIE4) {
    Attribute = Element.getAttribute(AttributeName);
    return Attribute;
  }
  if (NS4) {
    Attribute = Element[AttributeName]
    if (!Attribute) {
       Attribute = false;
    }
    return Attribute;
  }
  return false;
}

function getContent (Mode, Identifier, ElementNumber) {
  var Content;
  var Element = getElement(Mode, Identifier, ElementNumber);
  if (!Element) {
    return false;
  }
  if (DOM && Element.firstChild) {
    if (Element.firstChild.nodeType == 3) {
      Content = Element.firstChild.nodeValue;
    } else {
      Content = "";
    }
    return Content;
  }
  if (MSIE4) {
    Content = Element.innerText;
    return Content;
  }
  return false;
}

function setContent (Mode, Identifier, ElementNumber, Text) {
  var Element = getElement(Mode, Identifier, ElementNumber);
  if (!Element) {
    return false;
  }
  if (DOM && Element.firstChild) {
    Element.firstChild.nodeValue = Text;
    return true;
  }
  if (MSIE4) {
    Element.innerText = Text;
    return true;
  }
  if (NS4) {
    Element.document.open();
    Element.document.write(Text);
    Element.document.close();
    return true;
  }
}

//window.addEventListener?window.addEventListener("load",so_init,false):window.attachEvent("onload",so_init);

var d=document, imgs = new Array(), zInterval = null, current=0, pause=false;

var currentTextIndex = 0;
var imgShowDuration = 2000;

function so_init() {
	if(!d.getElementById || !d.createElement)return;
	
	css = d.createElement("link");
	css.setAttribute("href","css/intro.css");
	css.setAttribute("rel","stylesheet");
	css.setAttribute("type","text/css");
	d.getElementsByTagName("head")[0].appendChild(css);
	
	imgs = d.getElementById("imageContainer").getElementsByTagName("img");
	for(i=1;i<imgs.length;i++){
		imgs[i].xOpacity = 0;
		
		imgs[i].style.visibility = "visible";
	}
	imgs[0].style.display = "block";
	imgs[0].xOpacity = .99;
	imgs[0].style.visibility = "visible";
	setImageContextText(imgs[0]);
	setTimeout(so_xfade,imgShowDuration);
}

function setImageContextText(img){
	value = img.getAttribute("dsctext");
	if(value){
		setContent ("id", "bottominfo", null, value);	
	}
	else{
		setContent ("id", "bottominfo", null, " ");	
	}
}

function so_xfade() {
	cOpacity = imgs[current].xOpacity;
	nIndex = imgs[current+1]?current+1:0;
	nOpacity = imgs[nIndex].xOpacity;
	
	cOpacity-=.05; 
	nOpacity+=.05;
	
	
	imgs[nIndex].style.display = "block";
	imgs[current].xOpacity = cOpacity;
	imgs[nIndex].xOpacity = nOpacity;
	
	setOpacity(imgs[current]); 
	setOpacity(imgs[nIndex]);

	if(imgs[current].xOpacity != .99){
		setImageContextText(imgs[nIndex]);
	}
	
	if(cOpacity<=0) {
		imgs[current].style.display = "none";
		current = nIndex;
		
		// set description
		//setImageContextText(imgs[nIndex]);
		
		setTimeout(so_xfade,imgShowDuration);
	} else {
		setTimeout(so_xfade,50);
	}
	
	function setOpacity(obj) {
		if(obj.xOpacity>.99) {
			obj.xOpacity = .99;
			
			return;
		}
		obj.style.opacity = obj.xOpacity;
		obj.style.MozOpacity = obj.xOpacity;
		obj.style.filter = "alpha(opacity=" + (obj.xOpacity*100) + ")";
	}
	
}
