// ----------------------------------------------------------------------
// 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
												 errorMessage, 
												 warnMessage)
{
  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, "commentsmallerror", errorMessage);  
      setfocus(valfield);
      return false;
    }
    else {
      msg (infofield, "commentsmallwarning", warnMessage);   // 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, "warn", "");  
  return true;
}

/*
\method	validateEmail1
\brief 	determines if the user has provided a valid email1
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/
function validateEmail1 (valfield, infofield, required, std) {
	var stat = commonCheck (valfield, infofield, required, "REQUIRED: please provide your email address", "") ;
	
	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, "commentsmallerror", "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, "commentsmallwarning", "Notice: Unusual e-mail address - please check");
	} else {
		msg (infofield, "commentsmallwarning", "");
	}
	
	
	//reset message to it's original
	msg (infofield, "commentsmall", std) ;
	return true ;return true;
}

/*
\method	validateEmail2
\brief 	determines if the users second email address matches their first
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/
function validateEmail2 (valfield, infofield, required, email1) {
	var stat = commonCheck (valfield, infofield, required, "REQUIRED: please provide your email address", "") ;
	
	if (stat != proceed) { 
		return stat ;
	}
	
	var tfld = trim(valfield.value);	// value of field with whitespace trimmed off
	var tfld2 = trim(email1.value);	// value of field with whitespace trimmed off
	
	if (tfld != tfld2) {
		msg (infofield, "commentsmallerror", "ERROR: Email addresses do not match") ;
		return false ;
	}
	
	//reset message to it's original
	msg (infofield, "commentsmall", "") ;
	return true ;
}

/*
\method	validateAge
\brief 	determines if the user has provided a valid age
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/
function validateAge (valfield, infofield, required) {
	var stat = commonCheck (valfield, infofield, required, "REQUIRED: please state your age", "") ;
	
	if (stat != proceed) {
		return stat ;
	}
	
	var tfld = trim(valfield.value) ;
	var ageRE = /^[0-9]{1,3}$/
	
	if (!ageRE.test(tfld)) {
		msg (infofield, "commentsmallerror", "ERROR: not a valid age");
		setfocus(valfield) ;
		return false ;
	}
	
	if (tfld >= 200) {
		msg (infofield, "commentsmallerror", "ERROR: not a valid age");
		setfocus (valfield) ;
		return false ;
	}
	
	if (tfld > 110) {
		msg (infofield, "commentsmallwarning", "Notice: Older than 110 - please check");
	}
	
	//reset message to it's original
	msg (infofield, "commentsmall", "") ;
	return true ;return true;
}

/*
\method	validateEditBox
\brief 	determines if the user has provides a value in a required edit box
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/
function validateEditBox  (valfield, infofield, required, std, error) {
	var stat = commonCheck (valfield, infofield, required, error, "") ;
	
	if (stat != proceed) {
		return stat ;
	}
	
	//reset message to it's original
	msg (infofield, "commentsmall", "") ;
	return true ;
}

/*
\method	validateComboBox
\brief 	determines if the user has selected a valid element from the list
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/

function validateComboBox  (valfield, infofield, required, std, error) {
	var stat = commonCheck (valfield, infofield, required, error, "") ;
	
	if (stat != proceed) {
		return stat ;
	}
	
	var tfld = trim(valfield.value);  // value of field with whitespace trimmed off
	
	if (tfld == "choose one") {
		msg (infofield, "commentsmallerror", error) ;
		return false ;
	}
	
	
	//reset message to it's original
	msg (infofield, "commentsmall", std) ;
	return true ;
}

/*
\method	validateLinuxDistribution
\brief 	determines if the user has included their distro when OS is linux
\notes	returns true if the browser is old
\author	Ryan Boucher
\version	1.0
*/

function validateLinuxDistribution (valfield, infofield, os) {
	var tfld = trim(os.value);  // value of field with whitespace trimmed off
	
	if (tfld == "Linux") {
		var stat = commonCheck (valfield, infofield, true, 'REQUIRED: please specify your Linux distribution', "") ;
		
		if (stat != proceed) {
			return stat ;
		}
	}
	
	//reset message to it's original
	msg (infofield, "commentsmall", 'only required if you specifed Linux as your operating system.') ;
	return true ;
}