///////////////////////////////
// STRING validation functions
///////////////////////////////

//
// do trim
//
function trim(str)
{
  return str.replace(/^\s+|\s+$/g, ''  );
}


//
// function that validates a string contains only alpha characters
//
function isAlpha( inputStr )
{
	for (var i=0; i<inputStr.length; i++)
	{
		var ch = inputStr.charAt(i);
		//alert("Checking character "+char);
		if (!((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')))
		{
			//alert("Invalid character");
			return false;
		}
	}
	return true;
}


//
// function that validates a string contains only alphanumeric characters
//
function isText( inputStr )
{
	for (var i=0; i<inputStr.length; i++)
	{
		var ch = inputStr.charAt(i);
		//alert("Checking character "+char);
		if (!((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || (ch >= '0' && ch <= '9')))
		{
			//alert("Invalid character");
			return false;
		}
	}
	return true;
}


//
// function that determines if an input value has been entered at all.
//
function isEmpty(inputStr)
{
	if (inputStr == null || ( inputStr.toString().search( /^\s*$/ ) != -1 ) )
	{
		return true;
	}
	return false;
}


//
// function to check string length is within specified range
//
function isRangeSizeValid(inputVal, lowerLimit, upperLimit)
{
	if (isEmpty(inputVal))
		return true;
	if ( lowerLimit != null && inputVal.length < lowerLimit)
			return false;
	if ( upperLimit != null && inputVal.length > upperLimit)
			return false;
	return true;
}




////////////////////////////////
// NUMERIC validation functions
////////////////////////////////
//


//
// general purpose function to check whether a numeric input is a positive integer or not
//
function isPosInteger(inputVal)
{
	inputStr = inputVal.toString()
	for (var i = 0; i < inputStr.length; i++)
	{
		var oneChar = inputStr.charAt(i);
		if (oneChar < "0" || oneChar > "9")
		{
			return false;
		}
	}
	return true;
}


//
// general purpose function to check whether the numeric input is a positive or negative integer
//
function isInteger(inputVal)
{
	inputStr = inputVal.toString()
	for (var i = 0; i < inputStr.length; i++)
	{
		var oneChar = inputStr.charAt(i)
		if (i == 0 && oneChar == "-")
		{
			continue;
		}
		if (oneChar < "0" || oneChar > "9")
		{
			return false;
		}
	}
	return true;
}


// 
// function to determine if value is in acceptable integer range
//
function inRange(inputStr, lowerLimit, upperLimit)
{
	if (isEmpty(inputStr))
		return true;
	if (!isInteger(inputStr))
		return false;
	num = parseInt(inputStr)
	if (lowerLimit != null && num < lowerLimit)
		return false;
	if (upperLimit != null && num > upperLimit)
		return false;
	return true;
}


//
// general purpose function to check if value is a real number
//
function isReal(inputVal)
{
	oneDecimal = false
	inputStr = inputVal.toString()
	for (var i = 0; i < inputStr.length; i++) {
		var oneChar = inputStr.charAt(i)
		if (i == 0 && oneChar == "-") {
			continue
		}
		if (oneChar == "." && !oneDecimal) {
			oneDecimal = true
			continue
		}
		if (oneChar < "0" || oneChar > "9") {
			return false
		}
	}
	return true
}


///////////////////////////////
// Australia Post code check
//////////////////////////////
function isPostcode( inputVal )
{
  inputStr = inputVal.toString();
  if ( inputStr.search( /^\d{3,4}$/ ) == -1 ) {
    return false;
  } else {
    return true;
  }
}


////////////////////////////
// Aust ABN number
////////////////////////////
function isABN( inputVal )
{
  inputStr = inputVal.toString();
  if ( inputStr.search( /^\d{2}( \d{3}){3}$|^\d{11}$/ ) == -1 ) {
    return false;
  } else {
    return true;
  }
}

/////////////////////////////
// DATE validation functions
/////////////////////////////


//
// check basic date syntax dd/mm/yyyy and date validity
//
function isValidDate(dateString)
{
	if (stringToDate(dateString) == null)
		return false;
	else
		return true;
}


//
// check date is valid and is before today
//
function isPastDate(dateString)
{
	if (isEmpty(dateString))
		return true;
	var d = stringToDate( dateString);
	var todaysDate = getTodaysDate();
	return dateCompare(d, "<=", todaysDate);
}


//
// check date is valid and is today or in the future
//
function isFutureDate(dateString)
{
	if (isEmpty(dateString))
		return true;
	var d = stringToDate( dateString);
	var todaysDate = getTodaysDate();
	return dateCompare(d, ">=", todaysDate);
}


//
// Converts a 2 digit year to a 4 digit year
//
function iY2KBlackBox(iYear)
{
	if (isNaN(iYear)) return '';

	// Detect if we got a 4 digit year. If not, add 2000 to it to make it a reasonable year
	if (iYear.length <= 2)
	{
		iYear = parseInt(iYear) + 2000;
	}
	else
	{
		iYear = parseInt(iYear);
	}
	return iYear;
}


//
// Function determines whether the integer components make up a valid date
//
function DayOK(iDay, iMonth, iYear)
{
	if ( (iMonth == 01) || (iMonth == 03) || (iMonth == 05) || (iMonth == 07) || (iMonth == 08) || (iMonth == 10) || (iMonth == 12) )
	{
		return (iDay >= 01 && iDay <= 31);
	}
	else
	{
		if (iMonth == 02)
		{
			if ((iYear % 4 == 0) && ( (!(iYear % 100 == 0)) || (iYear % 400 == 0) ) )
			{
				// 29 days in Feb during leap year
				return (iDay >= 01 && iDay <= 29);
			}
			else
			{
				// 28 days otherwise
				return (iDay >= 01 && iDay <= 28);
			}
		}
		else
		{
			if ( (iMonth == 04) || (iMonth == 06) || (iMonth == 09) || (iMonth == 11) )
			{
				return (iDay >= 01 && iDay <= 30);
			}
		}
	}
}


//
// Converts a string in the format dd/mm/yy and returns a date.
// Returns null if date is not valid. 
//
function stringToDate( dateString )
{
	//alert("Running stringToDate on "+dateString);
	// Check for empty string
	if (dateString == null || dateString == "")
		return null;

	// Check basic date syntax
	var dateParts = dateString.split('/');
	for (var i = 0; i < 3; ++i)
	{
		if (dateParts[i]==null || !isPosInteger(dateParts[i]))
			return null;
	}
	var day = dateParts[0];
	var month = dateParts[1];
	
	//Check the corect number of digits for each date Part
	if ((day.length > 2) || (month.length > 2))
		return null;
	
	var year = iY2KBlackBox(dateParts[2]);
	
	if (year > 9999)
	 return null;

	// Check it is a valid date
	if ( !DayOK( day, month, year) )
		return null;
	
	var theDate = new Date( year, month-1, day);

	return theDate;
}


//
// Converts a date to a string in the format dd/mm/yyyy
//
function dateToString( theDate )
{
	var theDateString;
	var day = theDate.getDate();
	var month = theDate.getMonth()+1;
	var year = theDate.getFullYear();
	theDateString = (day < 10) ? "0"+day : day;
	theDateString = theDateString + "/";
	theDateString = theDateString + ((month < 10) ? "0"+month : month);
	theDateString = theDateString + "/";
	theDateString = theDateString + year;
	return theDateString;
}


//
// Returns today's date with the time component removed
//
function getTodaysDate()
{
	var todaysDate = new Date();
	return new Date( todaysDate.getFullYear(), todaysDate.getMonth(), todaysDate.getDate() );
}