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

// ----------------------------------------------
//					mid
// Returns part of string - safely
// -------------------------------------------
function Mid(str, start, len)
{
// Make sure start and len are within proper bounds
    if (start < 0 || len < 0) return "";
    var iEnd, iLen = String(str).length;
    if (start + len > iLen)
          iEnd = iLen;
    else
          iEnd = start + len;
    return String(str).substring(start,iEnd);
}

// --------------------------------------------
//                  instr
// Looks for character in string.  Returns position or -1 if not found
// --------------------------------------------
function InStr(strSearch, charSearchFor)
{
            for (var i=0; i < strSearch.length; i++)
            {
                  if (charSearchFor == Mid(strSearch, i, 1))
                  {
                        return i;
                  }
            }
            return -1;
}


// --------------------------------------------
//                  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;  

// ----------------------------
//      trim - removes leading and trailing spaces
// ----------------------------




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");  
        setfocus(valfield);
        return false;
      }
      else {
        msg (infofield, "warn", "");   // 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;
}


// -----------------------------------------
//			validateHasSpace
// Validate if string has a space after position 1
// returns true if so
// -----------------------------------------
function validateHasSpace(valfield,   // element to be validated
						  infofield,  // id of element to receive info/error msg
						  errtxt)
{
  var stat = commonCheck(valfield, infofield, true);
  if (stat != proceed) return stat;
  var tfield = trim(valfield.value);
  stat = tfield.indexOf(" ");
  if (stat != -1) {
		   msg (infofield, "warn", "");
		   return true;
  		};
  msg (infofield, "error", errtxt);
  setfocus (valfield);
  return false;
}						  
 
// --------------------------------------------
//            validateDate
// validates that the date is OK and is in range
//
//---------------------------------------------
function validateDate(valfieldYear,		// Year as a select field
					  valfieldMonth,	// Month as a select field
					  valfieldDay,		// Day of month	as select field	
					  min, max,			// Minimum and Max diff from today 
					  infofield,		// field for message
					  errtxt )			// error text if out of range
{
  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  
     };


  var today  = new Date();
  var month = valfieldMonth.selectedIndex;
  var year  = parseInt(valfieldYear.options[valfieldYear.selectedIndex].text); 
  var day   = parseInt(valfieldDay.options[valfieldDay.selectedIndex].text);
  if ((year % 4) == 0) {
		 var maxDays = "312931303130313130313031"
  		}
  		else {
		 var maxDays = "312831303130313130313031"
 		};
 
  var maxDay = parseInt(Mid(maxDays, month*2, 2));
  if (parseInt(day) > maxDay) {
		 msg (infofield,'error', ' - invalid Day of month');
		 setfocus(valfieldDay);
		 return false;
  	    };        
  var odate = new Date(year,month,day,16); // Checkin is 4pm=16:00
  var days = parseInt((odate - today) / 86400000);
  if ((days < min) || (days>max)) {
		 msg (infofield,'error', errtxt);
		 setfocus(valfieldMonth);
		 return false;
  		};
  return true;
}

// --------------------------------------------
//            validateSelect
// Validate if something has been Selected
// Returns true if so 
// --------------------------------------------

function validateSelect(valfield,   // element to be validated
                         infofield, // id of element to receive info/error msg
						 dflttxt)	// Default Text to display if OK 
{
//  var stat = commonCheck (valfield, infofield, false);
//  if (stat != proceed) return stat;
//  if (!valfield.selectedIndex)
//  	return true;
  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  
     };


  var myindex=valfield.selectedIndex;
  

  if (myindex<1) {
	  msg (infofield, "error", " - Please select a value");
	  setfocus (valfield);
	  return false;
    };
  msg (infofield, "normal", dflttxt);  
  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", "- 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");
  else
    msg (infofield, "warn", "");
  return true;
}


// --------------------------------------------
//            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", "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", " - " + 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;
}

// --------------------------------------------
//             validateAge
// Validate person's age
// Returns true if OK 
// --------------------------------------------

function validateAge    (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 ageRE = /^[0-9]{1,3}$/
  if (!ageRE.test(tfld)) {
    msg (infofield, "error", " - not a valid age");
    setfocus(valfield);
    return false;
  }

  if (tfld>=200) {
    msg (infofield, "error", " - not a valid age");
    setfocus(valfield);
    return false;
  }

  if (tfld>110) msg (infofield, "warn", " - Older than 110: check correct");
  else {
    if (tfld<7) msg (infofield, "warn", " - Bit young for this, aren't you?");
    else        msg (infofield, "warn", "");
  }
  return true;
}