/* Checks if a value is in a numeric format */
function isNum(value)
{
	var testcase;
	var result;
  
	value = value.replace(',','');
	
	if( value == '' || value == null ){ return true; }
	
	testCase = /\d+\.?\d*/;
	if((result = testCase.exec( value )) == null)	{ return false; } else { return true; }
}



/**
 * Checks a value to see if it fits a date format
 *
 * @return	true if fits date format or is blank
 *					false otherwise, with error message
 */
function chkdate(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;
  strDate = datefield;

  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;
        alert("The date entered is invalid.  Use MM/DD/YYYY format.");
        return false;
      }
      else {
        strMonth = strDateArray[0];
        strDay = strDateArray[1];
        strYear = strDateArray[2];
      }
      booFound = true;
    }
    else {
      alert("The date entered is invalid.  Use MM/DD/YYYY format.");
      return false;
    }
  }
  if (strYear.length != 4) {
	  if(strYear.length == 2 ){ strYear = "19" + strYear; }
	  else
	  {
		  alert("Please enter the year as a 4 digit number: YYYY, 2002, etc...");
		  return false;
	  }
  }
  intday = parseInt(strDay, 10);
  if (isNaN(intday)) {
    err = 2;
    alert("The date entered is invalid.  Use MM/DD/YYYY format.");
    return false;
  }
  intMonth = parseInt(strMonth, 10);
  if (isNaN(intMonth)) {
    err = 3;
    alert("The date entered is invalid.  Use MM/DD/YYYY format.");
    return false;
  }
  intYear = parseInt(strYear, 10);
  if (isNaN(intYear)) {
    err = 4;
    alert("The date entered is invalid.  Use MM/DD/YYYY format.");
    return false;
  }
//  This next check is for SQL server.  SmallDateType doesnt like years outside this range
  if ((intYear < 1900) || (intYear > 2078))  {
    err = 4;
    alert("Please use a year between 1900 and 2078.");
    return false;
  }
  if (intMonth>12 || intMonth<1) {
    err = 5;
    alert("The month entered isnt between 1-12.  Use MM/DD/YYYY format.");
    return false;
  }
  if ((intMonth == 1 || intMonth == 3 || intMonth == 5 || intMonth == 7 || intMonth == 8 || intMonth == 10 || intMonth == 12) && (intday > 31 || intday < 1)) {
    err = 6;
    alert("The day entered isn't between 1-31.  Use MM/DD/YYYY format.");
    return false;
  }
  if ((intMonth == 4 || intMonth == 6 || intMonth == 9 || intMonth == 11) && (intday > 30 || intday < 1)) {
    err = 7;
    alert("The date entered does not exist.  Use MM/DD/YYYY format.");
    return false;
  }
  if (intMonth == 2) {
    if (intday < 1) {
      err = 8;
      alert("The date entered does not exist.  Use MM/DD/YYYY format.");
      return false;
    }
    if (LeapYear(intYear) == true) {
      if (intday > 29) {
        err = 9;
        alert("The date entered does not exist.  Use MM/DD/YYYY format.");
        return false;
      }
    }
    else {
      if (intday > 28) {
        err = 10;
        alert("The date entered does not exist.  Use MM/DD/YYYY format.");
        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;
}