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", "X"); 
      return false;
    }
    else {
      msg (infofield, "ok", "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, "ok", "OK");  
  return true;
}

// --------------------------------------------
//               validateSelect
// Validate if selected
// Returns true if value isn't empty 
// --------------------------------------------

function validateSelect  (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;
  		
  		if (!valfield.options[valfield.selectedIndex].value) {  //if value is empty
   		msg (infofield, "error", "X");
   		valfield.submit.disabled = true;
   		return false;
		}
  		else {
    		msg (infofield, "ok", "OK");
    		return true;
  		}
}

// --------------------------------------------
//             validateRegexp 
// Validate person's Regular expression
// Returns true if OK
// --------------------------------------------

function validateRegexp (valfield,   // element to be validated
						 		 regexp,	 // Regular expression
                         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 = valfield.value;
  if (!regexp.test(tfld)) {
    msg (infofield, "error", "X");
    return false;
  }
  else{
  	msg (infofield, "ok", "OK");
  	return true;
  }
}