function getHTTPObject() {
    if (typeof XMLHttpRequest != 'undefined') {
        return new XMLHttpRequest();
    }
    try {
        return new ActiveXObject("Msxml2.XMLHTTP");
    } catch (e) {
        try {
            return new ActiveXObject("Microsoft.XMLHTTP");
        } catch (e) {}
    }
    return false;
}

function gLoad(strURL,div){   
	 // alert(strURL);      
     var req = getHTTPObject(); // fuction to get xmlhttp object
     if (req){
      req.onreadystatechange = function()     {
		  if (req.readyState == 4) {
			//if(document.getElementById(div)){
			  	document.getElementById(div).style.display="block";
				document.getElementById(div).innerHTML='<form name="form_'+div+'" id="form_'+div+'">'+req.responseText+'</form>';
			//}
      	  }        
      }        
    req.open("GET", strURL, true);
    req.send(null);
     }
}

function step1(usage){	
	gLoad('compare/form_step1.php?usage='+usage,'step1');
}

function step2(){	
	var dis=document.getElementById('step1');
	dis.style.display='none';
	var dis=document.getElementById('step2');
	dis.style.display='block';
	var dis=document.getElementById('step3');
	dis.style.display='none';
	var usage=document.getElementById('usage');
	var usageValue=usage.options[usage.selectedIndex].value;
	//alert(usageValue);
	gLoad('compare/form_step2.php?usage_value='+usageValue,'step2');
}

function step2b(){	
	var dis=document.getElementById('step2');
	dis.style.display='block';
	var dis=document.getElementById('step3');
	dis.style.display='none';
	var dis=document.getElementById('step4');
	dis.style.display='none';
}

function step3(){	
	var dis=document.getElementById('step2');
	dis.style.display='none';
	var dis=document.getElementById('step3');
	dis.style.display='block';
	var dis=document.getElementById('step4');
	dis.style.display='none';
	gLoad('compare/compare_parse.php','step3');
}
function step3b(){	
	var dis=document.getElementById('step2');
	dis.style.display='none';
	var dis=document.getElementById('step4');
	dis.style.display='none';
	var dis=document.getElementById('step3');
	dis.style.display='block';
}

function step4(pid){	
	var dis=document.getElementById('step3');
	dis.style.display='none';
	gLoad('product_data/compare_data.php?id='+pid,'step4');
}


function buildGetString(formName){
		var x=document.forms[formName];
		var stringy='';
		for (var i=0;i<x.length;i++){
			var sid=x.elements[i].name;
			var sva=x.elements[i].value;
			var type=x.elements[i].type;
			if(type=='checkbox'){
				if (x.elements[i].checked == true){
		  			stringy=stringy+sid+'='+sva+'&';
				}
			}else{
				if(sva){
		  		stringy=stringy+sid+'='+sva+'&';
				}
			}
		  }
		  return stringy;
}



 function maxNum(maxchars,el) {
	 element=document.getElementById(el);
 if(element.value.length > maxchars) {
	 alert('Sorry, but only '+maxchars+' characters are allowed here.');
	 element.value = element.value.substring(0, maxchars);
   return false; }
 else
   return true; }

function formValidation(oEvent) { 
	oEvent = oEvent || window.event; 
	var value;
	var txtField = oEvent.target || oEvent.srcElement; 
	if(txtField.type=='checkbox'){
		if(txtField.checked!=true){
				value='Unchecked';
		}else{
			value=txtField.value;
		}
	}else{
		value=txtField.value
	}
	sessionRunner('php_parse/form_session_handler.php?name='+txtField.name+'&value='+value);
} 

step1(' ');