// ----------------------------------------------------------------------
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

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

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

function setfocus(valfield)
{
  global_valfield = valfield;
  setTimeout( 'setFocusDelayed()', 100 );
}

function msg(fld, 
             msgtype, 
             message)
{

  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; 
}

var proceed = 2;  

function commonCheck    (valfield, 
                         infofield, 
                         required) 
{
  if (!document.getElementById) 
    return true; 
  var elem = document.getElementById(infofield);
  if (!elem.firstChild) return true; 
  if (elem.firstChild.nodeType != node_text) return true; 

  if (emptyString.test(valfield.value)) {
    if (required) {
      msg (infofield, "error", "ERROR: required");  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "warn", ""); 
      return true;  
    }
  }
  return proceed;
}

function validatePresent(valfield, 
                         infofield ) 
{
  var stat = commonCheck (valfield, infofield, true);
  if (stat != proceed) return stat;

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

function validateEmail  (valfield, 
                         infofield, 
                         required) 
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value); 
  var email = /^[^@]+@[^@.]+\.[^@]*\w\w$/  ;
  if (!email.test(tfld)) {
    msg (infofield, "error", "ERROR: not valid");
    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;
}

function validateZip  (valfield, 
                         infofield, 
                         required) 
{
  var stat = commonCheck (valfield, infofield, required);
  if (stat != proceed) return stat;

  var tfld = trim(valfield.value); 
  var telnr = /^\+?[0-9 ()-]+[0-9]$/  ;
  if (!telnr.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid zip code. Only numerals please");
    setfocus(valfield);
    return false;
  }

  var numdigits = 0;
  for (var j=0; j<tfld.length; j++)
    if (tfld.charAt(j)>='0' && tfld.charAt(j)<='6') numdigits++;

  if (numdigits<5) {
    msg (infofield, "error", "ERROR: " + numdigits + " digits - too short");
    setfocus(valfield);
    return false;
  }

  return true;
}