// ----------------------------------------------------------------------
// Javascript form validation routines.
// Author: Stephen Poley
// URL: http://www.xs4all.nl/~sbpoley/webmatters/formval.html
// Simple routines to quickly pick up obvious typos.
// All validation routines return true if executed by an older browser:
// in this case validation must be left to the server.
// Update Jun 2005: discovered that reason IE wasn't setting focus was
// due to an IE timing bug. Added 0.1 sec delay to fix.
// Update Oct 2005: minor tidy-up: unused parameter removed
// Update Jun 2006: minor improvements to variable names and layout
// ----------------------------------------------------------------------

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

// --------------------------------------------
// trim - Trim leading/trailing whitespace off string
// --------------------------------------------

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
// --------------------------------------------
// id of element to display message in
// class to give element ("warn" or "error")
// string to display
function msg(fld, msgtype, message)	{
	// 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)
// --------------------------------------------
// element to be validated
// id of element to receive info/error msg
// true if required
var proceed = 2;
function commonCheck (valfield, infofield, 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) {
			/*
			if (infofield == "inf_name") {
				msg (infofield, "error", "What is your name?");
			} else if (infofield == "inf_email") {
				msg (infofield, "error", "What is your email address?");
			} else if (infofield == "inf_phone") {
				msg (infofield, "error", "What is your phone no?");
			} else if (infofield == "inf_message") {
				msg (infofield, "error", "Why are you contacting us?");
			} else {
			*/
				msg (infofield, "error", "X");
			/* } */
			setfocus(valfield);
			return false;
		} else {
			msg (infofield, "warn", "");	// OK
			return true;
		}
	}
	return proceed;
}

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

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

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

// --------------------------------------------
// validateProject - Validate if something has been entered
// Returns true if so 
// --------------------------------------------
// element to be validated
// id of element to receive info/error msg
function validateProject(valfield, infofield ) {
	//var stat = commonCheck (valfield, infofield, true);
	//if (stat != proceed) return stat;
	if (valfield == 0);
	msg (infofield, "warn", "");
	return true;
}

// --------------------------------------------
// validateEmail - Validate if email address
// Returns true if so (and also if could not be executed because of old browser)
// --------------------------------------------
// element to be validated
// id of element to receive info/error msg
// true if required
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$/	;
	if (!email.test(tfld)) {
		msg (infofield, "error", "This isn't a valid email address");
		setfocus(valfield);
		return false;
	}
	var email2 = /^[A-Za-z][\w.-]+@\w[\w.-]+\.[\w.-]*[A-Za-z][A-Za-z]$/	;
	if (!email2.test(tfld)) 
		msg (infofield, "warn", "Unusual email address - check if correct");
	else
		msg (infofield, "warn", "");
	return true;
}

// --------------------------------------------
// validatePhone - Validate telephone number
// Returns true if so (and also if could not be executed because of old browser)
// Permits spaces, hyphens, brackets and leading +
// --------------------------------------------
// element to be validated
// id of element to receive info/error msg
// true if required
function validatePhone (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 telnr = /^\+?[0-9 ()-]+[0-9]$/	;
	if (!telnr.test(tfld)) {
		msg (infofield, "error", "This isn't a valid phone number");
		// msg (infofield, "error", "This isn't a valid telephone number. Characters permitted are digits, spaces, leading +, () and -");
		setfocus(valfield);
		return false;
	}
	var numdigits = 0;
	for (var j=0; j<tfld.length; j++)
		if (tfld.charAt(j)>='0' && tfld.charAt(j)<='9') numdigits++;
	if (numdigits<6) {
		msg (infofield, "error", "Error: " + numdigits + " digits - too short");
		setfocus(valfield);
		return false;
	}
	if (numdigits>14)
		msg (infofield, "warn", numdigits + " digits - check if correct");
	else { 
		if (numdigits<10)
			msg (infofield, "warn", "Only " + numdigits + " digits - check if correct");
		else
			msg (infofield, "warn", "");
	}
	return true;
}

// --------------------------------------------
// validateAge - Validate person's age
// Returns true if OK 
// --------------------------------------------
// element to be validated
// id of element to receive info/error msg
// true if required
function validateAge (valfield, infofield, required) {
	var stat = commonCheck (valfield, infofield, required);
	if (stat != proceed) return stat;
	var tfld = trim(valfield.value);
	var ageRE = /^[0-9]{1,3}$/
	if (!ageRE.test(tfld)) {
		msg (infofield, "error", "Error: not a valid age");
		setfocus(valfield);
		return false;
	}
	if (tfld>=200) {
		msg (infofield, "error", "Error: not a valid age");
		setfocus(valfield);
		return false;
	}
	if (tfld>110) msg (infofield, "warn", "Older than 110: check correct");
	else {
		if (tfld<7) msg (infofield, "warn", "Bit young for this, aren't you?");
		else msg (infofield, "warn", "");
	}
	return true;
}

function validateFiletype(field, ext) {
	if (field.value.indexOf('.' + ext) == -1) {
		return false;
	}
	return true;
}