// ----------------------------------------------------------------------
// Javascript form validation routines.
// Author: Stephen Poley
// Modified 22/06/2006 By Jon Cotton on Behalf of Label Media Ltd
//
// 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 validateLoaded = true; //GLOBAL: this is used to test if the script has been loaded

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
var changeCount = 0;
var firstError = true;
var firstField;

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

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

// --------------------------------------------
//                  initialCap
// Makes the first letter of the string uppercase
// --------------------------------------------

function initialCap(str) {
   return str.substr(0, 1).toUpperCase() + str.substr(1);
}


// --------------------------------------------
//                  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 );
	if (firstError) {
		firstField = global_valfield;
		firstError = false;
	}

}

// --------------------------------------------
//                  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
             valfield) // id of element that message applies to
{
  // 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 = initialCap(valfield.name) + ": " + message;

  var elem = document.getElementById(fld);
  elem.firstChild.nodeValue = dispmessage;
  elem.style.display = "inline";
  elem.style.visibility = "visible";
  
  valfield.className = "input_" + msgtype; //change the class of the element that the message applies to
 
}

// --------------------------------------------
//            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", valfield); 	 
      setfocus(valfield);
      return false;
    } else {
		document.getElementById(infofield).style.display = "none";
		document.getElementById(infofield).style.visibility = "hidden";
		valfield.className = false;
      	return true;
    }
  }
  document.getElementById(infofield).style.display = "none";
  document.getElementById(infofield).style.visibility = "hidden";
  valfield.className = false;
  return proceed;
}

// --------------------------------------------
//               validateEmail
// Validate if e-mail address
// Returns true if so (and also if could not be executed because of old browser)
// --------------------------------------------

function validateEmail  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if 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", "Not a valid e-mail address", valfield);
    setfocus(valfield);
    return false;
  } else {
  	document.getElementById(infofield).style.display = "none";
  	document.getElementById(infofield).style.visibility = "hidden";
  	valfield.className = false;
	return true;
  }
  
}

// --------------------------------------------
//            validateTelnr
// Validate telephone number
// Returns true if so (and also if could not be executed because of old browser)
// Permits spaces, hyphens, brackets and leading +
// --------------------------------------------

function validateTelnr  (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if 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", "Not a valid telephone/fax number", valfield);
    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", numdigits + " digits - too short", valfield);
    setfocus(valfield);
    return false;
  }
  document.getElementById(infofield).style.display = "none";
  document.getElementById(infofield).style.visibility = "hidden";
  valfield.className = false;
  return true;
  
}

// --------------------------------------------
//             validateDate
// Validate a date to UK Date Format (DD/MON/YYYY)
// Returns true if OK 
// --------------------------------------------
function validateDate    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value);
  var dateRE = /^(0[1-9]|[12][0-9]|3[01])[-](Jan|Feb|Mar|Apr|May|Jun|Jul|Aug|Sep|Oct|Nov|Dec)[-](19|20)\d\d$/i;
  if (!dateRE.test(tfld)) {
    msg (infofield, "error", "not a valid date (dd-mon-yyyy)", valfield);
    setfocus(valfield);
    return false;
  } else {
  	document.getElementById(infofield).style.display = "none";
  	document.getElementById(infofield).style.visibility = "hidden";
  	valfield.className = false;
	return true;
  }
  
}

// --------------------------------------------
//             validateStr
// Validate a str
// Returns true if OK 
// --------------------------------------------
function validateStr    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;
	
  document.getElementById(infofield).style.display = "none";
  document.getElementById(infofield).style.visibility = "hidden";
  valfield.className = false;
  return true;
  
}

// --------------------------------------------
//             validateNum
// Validate a number
// Returns true if OK 
// --------------------------------------------
function validateNum    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;
  
  var tfld = trim(valfield.value);
  var numRE = /^[-+]?([0-9]*\.[0-9]+|[0-9]+)$/
  if (!numRE.test(tfld)) {
    msg (infofield, "error", "not a valid number", valfield);
    setfocus(valfield);
    return false;
  } else {
  	document.getElementById(infofield).style.display = "none";
  	document.getElementById(infofield).style.visibility = "hidden";
  	valfield.className = false;
	return true;
  }
  
}

// --------------------------------------------
//             validatePcode
// Validate a UK Postcode
//Return true if OK
// --------------------------------------------
function validatePcode    (valfield,   // element to be validated
                         infofield,  // id of element to receive info/error msg
                         required)   // true if required
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;
  
  var tfld = trim(valfield.value);
  var pcodeRE = /^[a-zA-Z]{1,2}[0-9][0-9A-Za-z]{0,1} {0,1}[0-9][A-Za-z]{2}$/
  if (!pcodeRE.test(tfld)) {
    msg (infofield, "error", "not a valid UK Postcode", valfield);
    setfocus(valfield);
    return false;
  } else {
  	document.getElementById(infofield).style.display = "none";
  	document.getElementById(infofield).style.visibility = "hidden";
  	valfield.className = false;
	return true;
  }
  
}

function checkChanges() {
	
	if (changeCount > 0) {
		response = confirm('Warning Changes Detected: Would you like to save the changes to this form?');
		if (response) {
			document.forms[0].submit();
			return false;
		} else {
			return true;
		}
	} else {
		return true;
	}
	
}