// JavaScript Document

//Ajax Function
function getXMLHttp()
{
  var xmlHttp

  try
  {
    //Firefox, Opera 8.0+, Safari
    xmlHttp = new XMLHttpRequest();
  }
  catch(e)
  {
    //Internet Explorer
    try
    {
      xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
    }
    catch(e)
    {
      try
      {
        xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
      }
      catch(e)
      {
        alert("Your browser does not support AJAX!")
        return false;
      }
    }
  }
  return xmlHttp;
}


function choose_depends(box,product_id)
{
	
var xmlHttp = getXMLHttp();
  
  	xmlHttp.onreadystatechange = function()
  	{
    if(xmlHttp.readyState == 4)
		{
		  Handle_dynamic(xmlHttp.responseText);
		}
	}
	
	var id = box.value;
	
	//var url= "websteed/ajax_index.php?subpage=dynamic_values&colour_id="+id+"&product_id="+product_id;
	var url= "ajax_index.php?subpage=dynamic_values&colour_id="+id+"&product_id="+product_id;

	var params='';
	xmlHttp.open("POST", url , true);
	xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	xmlHttp.setRequestHeader("Content-length", params.length);
	xmlHttp.setRequestHeader("Connection", "close");
	xmlHttp.send(params);
}

function Handle_dynamic(res)
{	
	document.getElementById('available_size').innerHTML=res;
	document.getElementById('available_quantity').innerHTML="";
}

function dynamic_quantity(box,product_id,colour_id)
{
var xmlHttp = getXMLHttp();
  
  	xmlHttp.onreadystatechange = function()
  	{
    if(xmlHttp.readyState == 4)
		{
		  Handle_dynamic_quantity(xmlHttp.responseText);
		}
	}
	
	var id = box.value;
	//alert("ajax_index.php?subpage=dynamic_quantity&size_id="+id+"&product_id="+product_id+"&colour_id="+colour_id);
	var url= "ajax_index.php?subpage=dynamic_quantity&size_id="+id+"&product_id="+product_id+"&colour_id="+colour_id;

	var params='';
	xmlHttp.open("POST", url , true);
	xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	xmlHttp.setRequestHeader("Content-length", params.length);
	xmlHttp.setRequestHeader("Connection", "close");
	xmlHttp.send(params);
}

function Handle_dynamic_quantity(res)
{	
	document.getElementById('available_quantity').innerHTML=res;
}


function SetOpacity(object,opacityPct)
{
  // IE.
  object.style.filter = 'alpha(opacity=' + opacityPct + ')';
  // Old mozilla and firefox
  object.style.MozOpacity = opacityPct/100;
  // Everything else.
  object.style.opacity = opacityPct/100;
}


function ChangeOpacity(id,msDuration,msStart,fromO,toO,val,altmsg)
{
  var element=document.getElementById(id);
  var opacity = element.style.opacity * 100;
  var msNow = (new Date()).getTime();
  opacity = fromO + (toO - fromO) * (msNow - msStart) / msDuration;
  
  if (opacity<0) 
  {
	FadeIn('thumnail_image',altmsg);
    //SetOpacity(element,0);
  }
  else if (opacity>100)
    SetOpacity(element,100)
  else
  {
    SetOpacity(element,opacity);
    element.timer = window.setTimeout("ChangeOpacity('" + id + "'," + msDuration + "," + msStart + "," + fromO + "," + toO + ",'" + val + "','"+altmsg+"')",1);
  }
}

function FadeIn(id,val,altmsg)
{
  var element=document.getElementById(id);
  element.innerHTML='<img src="./image.php?width=276&height=250&image=/images/products/'+val+'" alt="Loading"/>';
  if (element.timer) window.clearTimeout(element.timer); 
  var startMS = (new Date()).getTime();
  element.timer = window.setTimeout("ChangeOpacity('" + id + "',300," + startMS + ",0,100,'"+val+"','"+altmsg+"')",1);
}



function change_image(val,altmsg)
{
  var element=document.getElementById('thumnail_image');
  if (element.timer) window.clearTimeout(element.timer); 
  var startMS = (new Date()).getTime();
  element.timer = window.setTimeout("ChangeOpacity('thumnail_image',300," + startMS + ",100,0,'"+val+"','"+altmsg+"')",1);
}