// Set path to PHP script
    var phpscript ='http://www.csmproductsonline.com/admin/ajax.php'    
    function cal(type) {
     var w = document.getElementById(type+'_'+'width').value;
     w=parseInt(w);
     var s = document.getElementById(type+'_'+'sheets').value;
     s=parseInt(s);
     var l = document.getElementById(type+'_'+'length').value.split("-");
     l=parseInt(l[0]);
     document.getElementById(type+'_'+'total').value=(w/12)*s*l;
     document.getElementById(type+'_'+'total').readOnly=false;
    }
    
    


    /* ============================ MAKE XMLHttpRequest OBJECT ============================ */

    function createRequestObject() {

		var req;

		if(window.XMLHttpRequest){
			// Firefox, Safari, Opera...
			req = new XMLHttpRequest();
		}
        else if(window.ActiveXObject){
			// Internet Explorer 5+
			req = new ActiveXObject("Microsoft.XMLHTTP");
		}
        else{
			// There is an error creating the object,
			// just as an old browser is being used.
			alert('There was a problem creating the XMLHttpRequest object');
		}
		return req;
	}

	// Make the XMLHttpRequest object
	var http = createRequestObject();


    /* ============================ GET NEXT OPTIONS MENU VALUES ============================ */

    function getNextOptionsRequest(prodType,prodSource,filterBy,fieldToReturn,prodTypeId) {

           // alert(prodType);
           // alert(prodSource);
          
            //get the value of previous select elements
            var filterByArray='';
            for(var i=0;i<filterBy.length;i++){
               filterByArray+='filter_by%5B'+filterBy[i]+'%5D='+document.getElementById(prodSource+'_'+filterBy[i]).value+'&';
            }
            filterByArray=filterByArray.slice(0,filterByArray.length-1);//remove last &

            //alert(filterByArray);

            // Open PHP script for requests
            //http.open('get', phpscript, true);
            var params = 'product_type='+prodType+'&product_source='+prodSource+'&'+filterByArray+'&field_to_return='+fieldToReturn+'&product_type_id='+prodTypeId+'&task=getNextOptions&time='+Date();

            http.open('post', phpscript, true);
            http.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
            http.onreadystatechange = function(){getNextOptionsResponse(prodSource,fieldToReturn)};
            http.send(params);

    }//end function getNextOptionsRequest


  	function getNextOptionsResponse(prodSource,fieldToReturn) {

        if(http.readyState == 4 && http.status == 200){

			// Text returned from PHP script
			var response = http.responseText;

			if(response) {
                var selectRef=document.getElementById(prodSource+'_'+fieldToReturn);

                if(response=='no result'){
                   selectRef.disabled=true;
                }
                else{
                   selectRef.disabled=false;
                }

                var optionsValues=response.split('~');

                //delete prev select elements
                while(selectRef.firstChild){
                     selectRef.removeChild(selectRef.firstChild);
                }

                if(optionsValues.length>0){
                    //create first option
                    var optionRef=document.createElement('option');
                    optionRef.value='';
                    optionRef.appendChild(document.createTextNode('choose one'));
                    selectRef.appendChild(optionRef);

                    //create select option elements
                    for(var i=0; i < optionsValues.length; i++ ){
                      var optionRef=document.createElement('option');
                      optionRef.value=optionsValues[i];
                      optionRef.appendChild(document.createTextNode(optionsValues[i]));
                      selectRef.appendChild(optionRef);
                    }

                    selectRef.parentNode.style.width=selectRef.offsetWidth;

                }//end if optionsValues.length>0


			}//end if response
		}//end if finish

	}//end function getNextOptionsResponse



   /* ============================ GET PRODUCT DETAILS ============================ */
   function viewProductDetails(htmlContent){

     var divRefCart=document.getElementById('cart');

     if(!document.getElementById('product_details')){
       var divRef=document.createElement('div');

       divRef.id='product_details';
       divRef.style.top=((document.getElementById('cart').clientHeight)-200)+'px';
       divRefCart.appendChild(divRef);
     }
     else{
        var divRef=document.getElementById('product_details');
     }
     divRef.innerHTML='<a href="#" onclick="removeProductDetails();return false" id="close">close<\/a>'+"\n"+htmlContent;
   }//end function viewProductDetails

   function removeProductDetails(){
     document.getElementById('product_details').parentNode.removeChild(document.getElementById('product_details'));
   }


    function getProductDetailsRequest(id,pos) {
        var params = 'id='+id+'&pos='+pos+'&task=getProductDetails&time='+Date();

        http.open('post', phpscript, true);
        http.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
        http.onreadystatechange = getProductDetailsResponse;
        http.send(params);

    }//end function getNextOptionsRequest


    function getProductDetailsResponse() {

        if(http.readyState == 4 && http.status == 200){
			// Text returned from PHP script
			var response = http.responseText;
			if(response) {
               //alert(response);

                viewProductDetails(response);

			}//end if response
		}//end if finish

	}//end function getNextOptionsResponse