/*********************** FORM VALIDATION JAVASCRIPT CODE  *******************************/

var nbsp = 160;		// non-breaking space char
var node_text = 3;	// DOM text node-type
var emptyString = /^\s*$/ ;
var global_valfield;	// retain valfield for timer thread

	// --------------------------------------------
	function trim(str) {
		return str.replace(/^\s+|\s+$/g, '');
	}

	// --------------------------------------------
	//                  setfocus
	// Delayed focus setting to get around IE bug
	// --------------------------------------------
	function setFocusDelayed() {
		global_valfield.focus();
	}

	function setfocus(valfield) {
		// save valfield in global variable so value retained when routine exits
		global_valfield = valfield;
		setTimeout( 'setFocusDelayed()', 100 );
	}


	// --------------------------------------------
	//                  msg
	// Display warn/error message in HTML element.
	// commonCheck routine must have previously been called
	// --------------------------------------------

	function msg(fld,     // id of element to display message in
					msgtype, // class to give element ("warn" or "error")
							message) // string to display
	{
		// setting an empty string can give problems if later set to a 
		// non-empty string, so ensure a space present. (For Mozilla and Opera one could 
		// simply use a space, but IE demands something more, like a non-breaking space.)
		var dispmessage;
		if (emptyString.test(message)) 
			dispmessage = String.fromCharCode(nbsp);    
		else 
			dispmessage = message;

		var elem = document.getElementById(fld);
		elem.firstChild.nodeValue = dispmessage;  
		elem.className = msgtype;   // set the CSS class to adjust appearance of message
	}

	// --------------------------------------------
	//            commonCheck
	// Common code for all validation routines to:
	// (a) check for older / less-equipped browsers
	// (b) check if empty fields are required
	// Returns true (validation passed), 
	//         false (validation failed) or 
	//         proceed (don't know yet)
	// --------------------------------------------
	var proceed = 2;
	function commonCheck    (valfield,   // element to be validated
									infofield,  // id of element to receive info/error msg
											required)   // true if required
	{
		if (!document.getElementById) 
			return true;  // not available on this browser - leave validation to the server
			var elem = document.getElementById(infofield);
			if (!elem.firstChild) return true;  // not available on this browser 
			if (elem.firstChild.nodeType != node_text) return true;  // infofield is wrong type of node  
			if (emptyString.test(valfield.value)) {
			if (required) {
				msg (infofield, "error", "Required");  
				setfocus(valfield);
				return false;
			} else {
				msg (infofield, "warn", "");   // OK
				return true;
			}
		}
		return proceed;
	}

	// --------------------------------------------
	//            validatePresent
	// Validate if something has been entered
	// Returns true if so 
	// --------------------------------------------
	function validatePresent(valfield,   // element to be validated
									infofield ) // id of element to receive info/error msg
	{
		var stat = commonCheck (valfield, infofield, true);
		if (stat != proceed) return stat;

		msg (infofield, "warn", "");  
		return true;
	}

	// --------------------------------------------
	//               validateEmail
	// Validate if e-mail address
	// Returns true if so (and also if could not be executed because of old browser)
	// --------------------------------------------
	function validateEmail  (valfield, infofield, required)	{
		var stat = commonCheck (valfield, infofield, required);
		if (stat != proceed) return stat;
	
		var tfld = trim(valfield.value);  // value of field with whitespace trimmed off
		var email = /^[^@]+@[^@.]+\.[^@]*\w\w$/  ;
		if (!email.test(tfld)) {
			msg (infofield, "error", "ERROR: not a valid e-mail address");
			setfocus(valfield);
			return false;
		}
	
		var email2 = /^[A-Za-z][\w.-]+@\w[\w.-]+\.[\w.-]*[A-Za-z][A-Za-z]$/  ;
		if (!email2.test(tfld)) 
			msg (infofield, "warning", "Unusual e-mail address - check if correct");
		else
			msg (infofield, "warning", "");
		return true;
	}