// ----------------------------------------------------------------------
// Javascript form validation routines.
// Author: Stephen Poley
//
// 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, '');
}


// --------------------------------------------
//                  setFocusDelayed
// Delayed focus setting to get around IE bug
// --------------------------------------------

function setFocusDelayed() {
	global_valfield.focus();
}

// --------------------------------------------
//                  setfocus
// Delayed focus setting to get around IE bug
// --------------------------------------------

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
					 requiredMsg) { // valid 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 (requiredMsg != undefined) {
			msg (infofield, "error", requiredMsg);  
			//setfocus(valfield);
			return (false);
		}
		else {
			msg (infofield, "warn", " ");   // OK
			return (true);  
		}
	}
	return proceed;
}

// --------------------------------------------
//            validateRadioChecked
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validateRadioChecked(valfield) {   	// id of element to be validated
	 
	// set var radio_choice to false
	radio_choice = false;

	// Loop from zero to the one minus the number of radio button selections
	for (counter = 0; counter < valfield.length; counter++) {
		if(!(valfield[counter].type == "radio")) {		
			alert("validateRadioChecked called on non-radio button:" + valfield[counter].name);
			return (false);
		}
		// If a radio button has been selected it will return (true)
		// (If not it will return (false))
		if (valfield[counter].checked)
		radio_choice = true; 
	}

	if (!radio_choice) {
		// If there were no selections made display an alert box 
		return (false);
	}
	return (true);
}

// --------------------------------------------
//            validatePresent
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validatePresent(valfield,     // element to be validated
						 infofield,
						 requiredMsg ) { // id of element to receive info/error msg

	var stat = commonCheck (valfield, infofield, requiredMsg);
	if (stat != proceed) 
		return stat;

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

// --------------------------------------------
//            validateSelection
// Validate if something has been entered
// Returns true if so 
// --------------------------------------------

function validateSelection(valfield,  // element to be validated
						   infofield, // id of element to receive info/error msg
						   warning) {
							   
	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

	var success = (valfield.value != "Invalid");
	if (!success) {
		msg(infofield, "warn", warning);
		return (false);
	}
	else {
		msg(infofield, "warn", " ");  
		return (true);
	}
};

// --------------------------------------------
//               isValidEmail
// Validate if e-mail address
// Returns 0 if valid or the number of the test failed
// --------------------------------------------

function isValidEmail(val) {
	var tfld = trim(val);  // value of field with whitespace trimmed off
	var email = /^[^@]+@[^@.]+\.[^@]*\w\w$/;
	if (!email.test(tfld)) {
		return 1;
	}

	var email2 = /^[A-Za-z][\w.-]+@\w[\w.-]+\.[\w.-]*[A-Za-z][A-Za-z]$/;
	if (!email2.test(tfld))
		return 2;
	else
		return 0;
}

// --------------------------------------------
//               isValidEmail
// Validate if e-mail address
// Returns 0 if valid or the number of the test failed
// --------------------------------------------

function isValidZip(val) {
	var tfld = trim(val);  // value of field with whitespace trimmed off
	var zip = /^\d{5}([\-]\d{4})?$/;
	if (!zip.test(tfld)) 
		return 1;
	else
		return 0;
}

// --------------------------------------------
//            isValidTelephone
// Validate telephone number
// Returns 0 if valid or the number of the failed test
// Permits spaces, hyphens, brackets and leading +
// --------------------------------------------

function isValidTelephone(val) {
	var tfld = trim(val);  // value of field with whitespace trimmed off
	var telnr = /^\+?[0-9 ()-]+[0-9]$/  ;
	if (!telnr.test(tfld)) {
		return 1;
	}

	var numdigits = 0;
	for (var j=0; j<tfld.length; j++)
		if (tfld.charAt(j)>='0' && tfld.charAt(j)<='9') numdigits++;

	if (numdigits < 6) 
		return 2;
	
	if (numdigits > 14)
		return 3;
	else if (numdigits < 10)
		return 4;
	else
		return 0;
}