// JavaScript Document

//cross browser ajax object
function getHTTPObject(){
	var xhr = false;
	if(window.XMLHttpRequest){
		xhr = new XMLHttpRequest();
	}else if (window.ActiveXObject){
		try{
			xhr = new ActiveXObject("Msxml2.XMLHTTP");
		} catch(e){
			try{
				xhr = new ActiveXObject("Microsoft.XMLHTTP");
			}catch(e){
				xhr = false;
			}
		}
	}
	return xhr;
}

//post using the ajax function
function sendData(data){
	var request = getHTTPObject();
	if (request){
			//replace submit button with an image
			$('submitctr').innerHTML = '<img src="_images/submit_loading.gif" alt="Form is being processed..." title="Form is being processed..." />';
			request.onreadystatechange = function(){
				parseResponse(request);
			};
			request.open( "POST", "harvestform.php", true );
			request.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
			request.send(data);
			return true;
		}else{
			return false;	
		}
}

function prepareForm(){
		//if non-dom-compliant browser then exit
		if(!document.getElementById){
			return;	
		}
		//add event handler to form to capture submit
		$('emailform').onsubmit = function(){
			var data = $('emailform').serialize();
			return !sendData(data);
		};
}

function parseResponse(request){
	if(request.readyState == 4){
		if(request.status == 200 || request.status == 304){
			$('harvestform').innerHTML = request.responseText;
			prepareForm();
		}
	}	
}


window.onload = prepareForm;