// ----------------------------------------------------------------------
// Javascript form validation routines.
// Author: Stephen Poley
// Edited by: Helen Cheng on 3/13/07
//
// 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
// --------------------------------------------

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 field.");  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "warn", "");   // OK
      return true;  
    }
  }
  return proceed;
}

// --------------------------------------------
//            checkSelect for Client
// Common code for all validation routines to:
// (a) check for older / less-equipped browsers
// (b) check if select field is required
// Returns true (validation passed), 
//         false (validation failed) 
// --------------------------------------------

function checkSelect   (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  
 
 
    txt = valfield.options[valfield.selectedIndex].value;

	if (txt.match('None') ) {
	    if (required) {
   	  	msg (infofield, "error", "Required field.");  
	      setfocus(valfield);
	      return false;
	    }
    	else {
    	 msg (infofield, "warn", "");   // OK
     	 return true;  
	    }
  	}
	else return true;
}

// --------------------------------------------
//            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,   // 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", "Please enter 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 e-mail address - check if correct");
//  else
  msg (infofield, "warn", "");
  return true;
}



// --------------------------------------------
//             validateClient
// Validate that the user selected an email client.
// Returns true if OK 
// --------------------------------------------

function validateClient(valfield, infofield) 
{
	//make a list of all the allowed selection names
	var list = new RegExp("(None|Outlook 2007|Outlook 2003|Outlook 2002 (XP)|Outlook 2000|Lotus Notes 7|Lotus Notes 6.5|Lotus Notes 6|Eudora|Mozilla Thunderbird|Gmail|Yahoo Mail Client|Web-based Mail Client|Other)", "i");
	txt = valfield.options[valfield.selectedIndex].value; // find the value of the selected option

	if (list.test(txt))  //check if one of the selections is selected (this should always be the case)
	{
		if (txt.match('Other') ) {  // if the selection is "Other," show the optional text box
			document.getElementById('Other').style.visibility = 'visible';
			msg (infofield, "warn", "");
			return true;
			}

		if (txt.match('None') ) { // if the selection is "None," prompt the user to select a different choice
			msg (infofield, "error", "Please select an email client.");
			document.getElementById('Other').style.visibility = 'hidden';
			setfocus(valfield);
			return false;
			}
		document.getElementById('Other').style.visibility = 'hidden';  // re-hide the optional text box if it is shown and "Other" was unselected
		msg (infofield, "warn", "");
		return true;
	}
	else return false;
}



// --------------------------------------------
//            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", "ERROR: not a valid telephone number. Characters permitted are digits, space ()- and leading +");
    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;
}