window.onload = initAll;

function initAll() {

	for (var i=0; i< document.forms.length; i++) { //initiates form validations
			document.forms[i].onsubmit = checkValidForm; 
		} 
}

function checkValidForm() {  //form validation functions
	var allGood = true;
	var errormsg ="";
	var allTags = document.getElementsByTagName("*");

	for (var i=0; i<allTags.length; i++) {
		if (!validTag(allTags[i])) {
			allGood = false;
		}
	}
	
	if (!errormsg == "") {
		alert(errormsg);
	}
	
	return allGood;
	
function validTag(thisTag) { //checks each tag
		var thisTagCheck = true;
		var allClasses = thisTag.className.split(" ");
	
		for (var j=0; j<allClasses.length; j++) {
			validBasedOnClass(allClasses[j]);
		}
		
	return thisTagCheck;
	
function validBasedOnClass(thisClass) {  // checks each class
		switch(thisClass) {
			case "reqd":
				if (thisTag.value == "") {
					var lableText = thisTag.parentNode.innerText || thisTag.parentNode.textContent || ""; //need this for IE which does not have textContent
					var rtpos = lableText.indexOf("*");  //use lable to left of * in error message
					errormsg += lableText.substring(0,rtpos) + " is required\n" ;
					thisTagCheck = false;
				}
				break;
			case "email":
				if (!validEmail(thisTag.value)) {
					errormsg += "Email address is not valid\n" ;
					thisTagCheck = false;
				}
				break;
			default:
		}
	}
			
	}
	
function validEmail(email) { //does a general format test for valid email address
		var invalidChars = " /:,;";
	
		if (email == "") {
			return false;
		}
		for (var k=0; k<invalidChars.length; k++) {
			var badChar = invalidChars.charAt(k);
			if (email.indexOf(badChar) > -1) {
				return false;
			}
		}
		var atPos = email.indexOf("@",1);
		if (atPos == -1) {
			return false;
		}
		if (email.indexOf("@",atPos+1) != -1) {
			return false;
		}
		var periodPos = email.indexOf(".",atPos);
		if (periodPos == -1) {	
			return false;
		}
		if (periodPos+3 > email.length)	{
			return false;
		}
		return true;
	}
}