// Check browser version
var isNav4 = false, isNav5 = false, isIE4 = false
var strSeperator = "/"; 
var vDateType = 3; // Global value for type of date format
var vYearType = 4; //Set to 2 or 4 for number of digits in the year for Netscape
var vYearLength = 2; // Set to 4 if you want to force the user to enter 4 digits for the year before validating.
var err = 0; // Set the error code to a default of zero
if(navigator.appName == "Netscape") {
if (navigator.appVersion < "5") {
isNav4 = true;
isNav5 = false;
}
else
if (navigator.appVersion > "4") {
isNav4 = false;
isNav5 = true;
   }
}
else {
isIE4 = true;
}
function DateFormat(vDateName, vDateValue, e, dateCheck, dateType) {
vDateType = dateType;
if (vDateValue == "~") {
alert("AppVersion = "+navigator.appVersion+" \nNav. 4 Version = "+isNav4+" \nNav. 5 Version = "+isNav5+" \nIE Version = "+isIE4+" \nYear Type = "+vYearType+" \nDate Type = "+vDateType+" \nSeparator = "+strSeperator);
vDateName.value = "";
vDateName.focus();
return true;
}
var whichCode = (window.Event) ? e.which : e.keyCode;
if (vDateValue.length > 8 && isNav4) {
if ((vDateValue.indexOf("-") >= 1) || (vDateValue.indexOf("/") >= 1))
return true;
}
//Eliminate all the ASCII codes that are not valid
var alphaCheck = " abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ/-";
if (alphaCheck.indexOf(vDateValue) >= 1) {
if (isNav4) {
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
}
else {
vDateName.value = vDateName.value.substr(0, (vDateValue.length));
return false;
   }
}
if (whichCode == 8) //Ignore the Netscape value for backspace. IE has no value
return false;
else {
var strCheck = '47,48,49,50,51,52,53,54,55,56,57,58,59,95,96,97,98,99,100,101,102,103,104,105';
if (strCheck.indexOf(whichCode) != -1) {
if (isNav4) {
if (((vDateValue.length < 6 && dateCheck) || (vDateValue.length == 7 && dateCheck)) && (vDateValue.length >=1)) {
alert("Invalid Date\nPlease Re-Enter");
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
}
if (vDateValue.length == 6 && dateCheck) {
var mDay = vDateName.value.substr(2,2);
var mMonth = vDateName.value.substr(0,2);
var mYear = vDateName.value.substr(4,4)
//Turn a two digit year into a 4 digit year
if (mYear.length == 2 && vYearType == 4) {
var mToday = new Date();
//If the year is greater than 30 years from now use 19, otherwise use 20
var checkYear = mToday.getFullYear() + 30; 
var mCheckYear = '20' + mYear;
if (mCheckYear >= checkYear)
mYear = '19' + mYear;
else
mYear = '20' + mYear;
}
var vDateValueCheck = mMonth+strSeperator+mDay+strSeperator+mYear;
if (!dateValid(vDateValueCheck)) {
alert("Invalid Date\nPlease Re-Enter");
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
}
return true;
}
else {
// Reformat the date for validation and set date type to a 1
if (vDateValue.length >= 8  && dateCheck) {
if (vDateType == 3) // ddmmyyyy
{
var mMonth = vDateName.value.substr(2,2);
var mDay = vDateName.value.substr(0,2);
var mYear = vDateName.value.substr(4,4)
vDateName.value = mDay+strSeperator+mMonth+strSeperator+mYear;
}
//Create a temporary variable for storing the DateType and change
//the DateType to a 1 for validation.
var vDateTypeTemp = vDateType;
vDateType = 1;
var vDateValueCheck = mMonth+strSeperator+mDay+strSeperator+mYear;
if (!dateValid(vDateValueCheck)) {
alert("Invalid Date\nPlease Re-Enter");
vDateType = vDateTypeTemp;
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
}
vDateType = vDateTypeTemp;
return true;
}
else {
if (((vDateValue.length < 8 && dateCheck) || (vDateValue.length == 9 && dateCheck)) && (vDateValue.length >=1)) {
alert("Invalid Date\nPlease Re-Enter");
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
         }
      }
   }
}
else {
// Non isNav Check
if (((vDateValue.length < 8 && dateCheck) || (vDateValue.length == 9 && dateCheck)) && (vDateValue.length >=1)) {
alert("Invalid Date\nPlease Re-Enter");
vDateName.value = "";
vDateName.focus();
return true;
}
if (vDateValue.length >= 8 && dateCheck) {
if (vDateType == 3) // dd/mm/yyyy
{
var mDay = vDateName.value.substr(0,2);
var mMonth = vDateName.value.substr(3,2);
var mYear = vDateName.value.substr(6,4)
}
if (vYearLength == 4) {
if (mYear.length < 4) {
alert("Invalid Date\nPlease Re-Enter");
vDateName.value = "";
vDateName.focus();
return true;
   }
}
var vDateTypeTemp = vDateType;
vDateType = 1;
// Store reformatted date to new variable for validation.
var vDateValueCheck = mMonth+strSeperator+mDay+strSeperator+mYear;
if (mYear.length == 2 && vYearType == 4 && dateCheck) {
//Turn a two digit year into a 4 digit year
var mToday = new Date();
//If the year is greater than 30 years from now use 19, otherwise use 20
var checkYear = mToday.getFullYear() + 30; 
var mCheckYear = '20' + mYear;
if (mCheckYear >= checkYear)
mYear = '19' + mYear;
else
mYear = '20' + mYear;
vDateValueCheck = mMonth+strSeperator+mDay+strSeperator+mYear;
// Store the new value back to the field.  This function will
// not work with date type of 2 since the year is entered first.
if (vDateTypeTemp == 3) // dd/mm/yyyy
vDateName.value = mDay+strSeperator+mMonth+strSeperator+mYear;
} 
if (!dateValid(vDateValueCheck)) {
alert("Invalid Date\nPlease Re-Enter");
vDateType = vDateTypeTemp;
vDateName.value = "";
vDateName.focus();
return true;
}
vDateType = vDateTypeTemp;
return true;
}
else {
if (vDateType == 3) {
if (vDateValue.length == 2) {
vDateName.value = vDateValue+strSeperator;
}
if (vDateValue.length == 5) {
vDateName.value = vDateValue+strSeperator;
   }
}
return true;
   }
}
if (vDateValue.length == 10&& dateCheck) {
if (!dateValid(vDateName)) {
// Un-comment the next line of code for debugging the dateValid() function error messages
//alert(err);  
alert("Invalid Date\nPlease Re-Enter");
vDateName.focus();
vDateName.select();
   }
}
return false;
}
else {
// If the value is not in the string return the string minus the last
// key entered.
if (isNav4) {
vDateName.value = "";
vDateName.focus();
vDateName.select();
return false;
}
else
{
vDateName.value = vDateName.value.substr(0, (vDateValue.length));
return false;
         }
      }
   }
}
function dateValid(objName) {
var strDate;
var strDateArray;
var strDay;
var strMonth;
var strYear;
var intday;
var intMonth;
var intYear;
var booFound = false;
var datefield = objName;
var strSeparatorArray = new Array("-"," ","/",".");
var intElementNr;
// var err = 0;
var strMonthArray = new Array(12);
strMonthArray[0] = "Jan";
strMonthArray[1] = "Feb";
strMonthArray[2] = "Mar";
strMonthArray[3] = "Apr";
strMonthArray[4] = "May";
strMonthArray[5] = "Jun";
strMonthArray[6] = "Jul";
strMonthArray[7] = "Aug";
strMonthArray[8] = "Sep";
strMonthArray[9] = "Oct";
strMonthArray[10] = "Nov";
strMonthArray[11] = "Dec";
//strDate = datefield.value;
strDate = objName;
if (strDate.length < 1) {
return true;
}
for (intElementNr = 0; intElementNr < strSeparatorArray.length; intElementNr++) {
if (strDate.indexOf(strSeparatorArray[intElementNr]) != -1) {
strDateArray = strDate.split(strSeparatorArray[intElementNr]);
if (strDateArray.length != 3) {
err = 1;
return false;
}
else {
strDay = strDateArray[0];
strMonth = strDateArray[1];
strYear = strDateArray[2];
}
booFound = true;
   }
}
if (booFound == false) {
if (strDate.length>5) {
strDay = strDate.substr(0, 2);
strMonth = strDate.substr(2, 2);
strYear = strDate.substr(4);
   }
}
//Adjustment for short years entered
if (strYear.length == 2) {
strYear = '20' + strYear;
}
strTemp = strDay;
strDay = strMonth;
strMonth = strTemp;
intday = parseInt(strDay, 10);
if (isNaN(intday)) {
err = 2;
return false;
}
intMonth = parseInt(strMonth, 10);
if (isNaN(intMonth)) {
for (i = 0;i<12;i++) {
if (strMonth.toUpperCase() == strMonthArray[i].toUpperCase()) {
intMonth = i+1;
strMonth = strMonthArray[i];
i = 12;
   }
}
if (isNaN(intMonth)) {
err = 3;
return false;
   }
}
intYear = parseInt(strYear, 10);
if (isNaN(intYear)) {
err = 4;
return false;
}
if (intMonth>12 || intMonth<1) {
err = 5;
return false;
}
if ((intMonth == 1 || intMonth == 3 || intMonth == 5 || intMonth == 7 || intMonth == 8 || intMonth == 10 || intMonth == 12) && (intday > 31 || intday < 1)) {
err = 6;
return false;
}
if ((intMonth == 4 || intMonth == 6 || intMonth == 9 || intMonth == 11) && (intday > 30 || intday < 1)) {
err = 7;
return false;
}
if (intMonth == 2) {
if (intday < 1) {
err = 8;
return false;
}
if (LeapYear(intYear) == true) {
if (intday > 29) {
err = 9;
return false;
   }
}
else {
if (intday > 28) {
err = 10;
return false;
      }
   }
}
return true;
}
function LeapYear(intYear) {
if (intYear % 100 == 0) {
if (intYear % 400 == 0) { return true; }
}
else {
if ((intYear % 4) == 0) { return true; }
}
return false;
}
//  End -->




function isValidDate(dateStr) {

var mmddyyyy;

// Checks for the following valid date formats:
// DD/MM/YY    DD-MM-YYYY

datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/; // requires 4 digit year

var matchArray = dateStr.match(datePat); // is the format ok?
//if (matchArray == null) {
//alert(dateStr + " Date is not in a valid format.");
//return false;
//}

day = matchArray[1]; // parse date into variables
month = matchArray[3];
year = matchArray[4];


if (month < 1 || month > 12) { // check month range
alert("Month must be between 1 and 12.");
return false;
}
if (day < 1 || day > 31) {
alert("Day must be between 1 and 31.");
return false;
}
if ((month==4 || month==6 || month==9 || month==11) && day==31) {
alert("Month "+month+" doesn't have 31 days!")
return false;
}
if (month == 2) { // check for february 29th
var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
if (day>29 || (day==29 && !isleap)) {
alert("February " + year + " doesn't have " + day + " days!");
return false;
   }
}
mmddyyyy =  month + "/"+ day +"/"+ year;

return mmddyyyy;
}


function dateDiff(dateform,firstdate,seconddate,diff) {

date1 = new Date();
date2 = new Date();
diff  = new Date();

var d1;
var d2;

//d1=isValidDate(dateform.firstdate.value);
//d2=isValidDate(dateform.seconddate.value);


d1=isValidDate(firstdate.value);
d2=isValidDate(seconddate.value);


if (d1) 
   { // Validates first date 
   date1temp = new Date(d1);
   date1.setTime(date1temp.getTime());
   //alert ("date1  :" + date1temp);
 }
else return false; // otherwise exits


if (d2) 
  { // Validates second date 
   date2temp = new Date(d2);
   date2.setTime(date2temp.getTime());
  // alert ("date2  :" + date2temp);
  }
else return false; // otherwise exits

// sets difference date to difference of first date and second date

if (date2 >= date1) {

diff.setTime(Math.abs(date1.getTime() - date2.getTime()));





timediff = diff.getTime();

weeks = Math.floor(timediff / (1000 * 60 * 60 * 24 * 7));
timediff -= weeks * (1000 * 60 * 60 * 24 * 7);

days = Math.floor(timediff / (1000 * 60 * 60 * 24)); 
timediff -= days * (1000 * 60 * 60 * 24);

hours = Math.floor(timediff / (1000 * 60 * 60)); 
timediff -= hours * (1000 * 60 * 60);

mins = Math.floor(timediff / (1000 * 60)); 
timediff -= mins * (1000 * 60);

secs = Math.floor(timediff / 1000); 
timediff -= secs * 1000;

//dateform.difference.value = weeks  + " weeks, " + days + " days, " + hours + " hours, " + mins + " minutes, and " + secs + " seconds";
diff = weeks *7  +  days +1 ;
return diff;
}
else
{
  alert("Invalid To Date");
  dateform.seconddate.focus();
  dateform.difference.value="";
 }

 // form should never submit, returns false
}
//  End -->