var req = "", call = "";

function createRequestObject() {
	var ajaxobject;
	var browser = navigator.appName;
	if(browser == "Microsoft Internet Explorer"){
		ajaxobject = new ActiveXObject("Microsoft.XMLHTTP");
	}else{
		ajaxobject = new XMLHttpRequest();
	}
	return ajaxobject;
}

function callSite(pag, loc) {
	call.open('GET', pag, true);
	call.onreadystatechange = function() {
		if(call.readyState == 4 && call.status == 200){
			document.getElementById(loc).innerHTML = call.responseText;
		}
	};
	call.send(null);
}

function callSitePost(pag, req, loc) {
	call.open('POST', pag, true);
	call.onreadystatechange = function() {
		if(call.readyState == 4 && call.status == 200){
			document.getElementById(loc).innerHTML = call.responseText;
		}
	};
	call.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	call.setRequestHeader("Content-length", req.length);
	call.setRequestHeader("Connection", "close");
	call.send(req);
}

function validate(field, dat) {
	var loc = 'msg_' + field;
	document.getElementById("msg_Name").innerHTML = "";
	document.getElementById("msg_Email").innerHTML = "";
	document.getElementById("msg_Subject").innerHTML = "";
	document.getElementById("msg_Message").innerHTML = "";
	document.getElementById("msg_Image").innerHTML = "";
	document.getElementById("msg_Result").innerHTML = "";
	if(field == "Name") {
		req = "?name=" + encodeURI(dat);
	} else if(field == "Email") {
		req = "?email=" + encodeURI(dat);
	} else if(field == "Subject") {
		req = "?subject=" + encodeURI(dat);
	} else if(field == "Message") {
		req = "?message=" + encodeURI(dat);
	} else if(field == "Image") {
		req = "?image=" + encodeURI(dat);
	}
	callSite('validate.php' + req, loc);
}

function submitForm() {
	var loc = 'msg_Result';
	document.getElementById("msg_Name").innerHTML = "";
	document.getElementById("msg_Email").innerHTML = "";
	document.getElementById("msg_Subject").innerHTML = "";
	document.getElementById("msg_Message").innerHTML = "";
	document.getElementById("msg_Image").innerHTML = "";
	document.getElementById("msg_Result").innerHTML = "";
	req = "name=" + escape(encodeURI(document.getElementById("name").value)) + 
		"&email=" + escape(encodeURI(document.getElementById("email").value)) + 
		"&subject=" + escape(encodeURI(document.getElementById("subject").value)) + 
		"&message=" + escape(encodeURI(document.getElementById("message").value)) + 
		"&image=" + escape(encodeURI(document.getElementById("image").value));
	callSitePost('submitForm.php', req, loc);
}

function clearField(thing) {
	if(thing.value == thing.defaultValue) {
		thing.value = "";
	}
}

call = createRequestObject();