// ----------------------------------------------------------------------
// 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, '');
}



// --------------------------------------------
//                  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", "ERROR: required");  
      setfocus(valfield);
      return false;
    }
    else {
      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, "warn", "");  
  return true;
}



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", "ERROR: not a valid e-mail 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 - Is this correct?");
  } else {
    msg (infofield, "warn", "*");
  }
  return true;
}



function validatePh1  (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]{3}$/  ;
  if (!telnr.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid telephone number");
    setfocus(valfield);
    return false;
  } else {
    msg (infofield, "warn", " ");
  }
  return true;
}



function validatePh2  (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]{3}$/  ;
  if (!telnr.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid telephone number");
    setfocus(valfield);
    return false;
  } else {
    msg (infofield, "warn", " ");
  }
  return true;
}



function validatePh3  (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]{4}$/  ;
  if (!telnr.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid telephone number");
    setfocus(valfield);
    return false;
  } else {
    msg (infofield, "warn", " ");
  }
  return true;
}



function validateZip    (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 zip = /^\d{5}$/ ;
	if (!zip.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid zip code");
    setfocus(valfield);
    return false;
  } else {
    msg (infofield, "warn", "*");
  }
  return true;
}



function validateName    (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);

  if (tfld.length == 1)
  {
	  msg (infofield, "warn", "Is this correct?");
  } else {
    msg (infofield, "warn", "*");
  }
  
  return true;
}



function validateMM    (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 tfldint = parseInt(tfld, 10);
  if (tfldint > 12 || tfldint < 1) {
  	msg (infofield, "error", "Error: not a valid date");
  	setfocus(valfield);
	  return false;
  } else {
    msg (infofield, "warn", "*");
  }
  
  return true;
}



function validateDD    (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 tfldint = parseInt(tfld, 10);
  if (tfldint > 31 || tfldint < 1) {
  	msg (infofield, "error", "Error: not a valid date");
  	setfocus(valfield);
	  return false;
  } else {
    msg (infofield, "warn", "*");
  }
  
  return true;
}



function validateYYYY    (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 tfldint = parseInt(tfld, 10);

	var d = new Date();
  if ((tfldint > (d.getFullYear() - 15)) || (tfldint < (d.getFullYear() - 125))) {
  	msg (infofield, "error", "Error: not a valid date");
  	setfocus(valfield);
	  return false;
  } else {
    msg (infofield, "warn", "*");
  }
  
  return true;
}



function validateCity	   (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);

  if (tfld.length == 1)
  {
  	msg (infofield, "warn", "Is this correct?");
  } else {
    msg (infofield, "warn", " ");
  }
  
  return true;
}



function validateStreet  (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 street = /^([0-9A-Za-z\.\W]+)$/ ;
  if (!street.test(tfld)) {
    msg (infofield, "error", "ERROR: not a valid street address");
    setfocus(valfield);
    return false;
  } else {
    msg (infofield, "warn", " ");
  }
	return true;
}