var idFormstart = 'shop_name';
var idConfirmer = 'shop_confirm';
var idSubmit = 'shop_submit';
var reqFields = Array();

window.onload = function() {
	if (!document.getElementById) return false;
	disableForm();
	document.getElementById(idFormstart).focus();
}

function disableForm() {
	if (!document.getElementById) return false;
	document.getElementById(idSubmit).disabled = true;
	attachEventListener(document.getElementById(idConfirmer), 'click', validateForm, false);
	for (iReq = 0; iReq < reqFields.length; iReq++) {
		attachEventListener(document.getElementById(reqFields[iReq]), 'keyup', validateForm, false);
	}
}

function validateForm() {
	if (!document.getElementById) return false;
	var iFalse = 0;
	if (document.getElementById(idConfirmer).checked == false) iFalse++;
	for (iReq = 0; iReq < reqFields.length; iReq++) {
		if (document.getElementById(reqFields[iReq]).value == '') iFalse++;
	}
	if (iFalse == 0) {
		document.getElementById(idSubmit).disabled = false;
	} else {
		document.getElementById(idSubmit).disabled = true;
	}
}


function attachEventListener(target, eventType, functionRef, capture) {
	if (typeof target.addEventListener != "undefined") {
	   target.addEventListener(eventType, functionRef, capture);
	} else if (typeof target.attachEvent != "undefined") {
		target.attachEvent("on" + eventType, functionRef);
	} else {
		eventType = "on" + eventType;
		if (typeof target[eventType] == "function") {
			var oldListener = target[eventType];
			target[eventType] = function() {
				oldListener();
				return functionRef();
			};
		} else {
			target[eventType] = functionRef;
		}
	}
}