function CalcLMP(lmp_id, weeks, edd, which)
{
	data = document.getElementById(lmp_id).value;
	if (data.length==0)
	{
		if ((which==0)||(which==1))
 			document.getElementById(weeks).value = ""
 		if ((which==0)||(which==2))
 			document.getElementById(edd).value = ""
 		return;
 	}
 		
 	var today = new Date();
 	var lmp = ConvertStrToDate(data)

	days = GetTotalDays(today - lmp)
	if (days > 42*7)
		w = "heigh"
	else if (days >= 7)
		w = parseInt((days / 7), 10) +"w"+ (days % 7) + "d";
	else
		w = days + "d"
	
	if ((which==0)||(which==1))
		document.getElementById(weeks).value = w
	today.setTime( today.getTime() + AddDays(40*7 - days) )
	if ((which==0)||(which==2))
		document.getElementById(edd).value = ConvertDateToStr(today)
}

function AddDays(days)
{
	var hour = 1000*60*60
	var day = hour*24

	return 	day * days;
}

function ConvertStrToDate(str)
{
	if (str.length != 10)
		return null;
	
	var date = new Date();
	date.setFullYear(str.substring(6), str.substring(3,5)-1, str.substring(0,2)-1)
	return 	date;
}

function ConvertDateToStr(date)
{
	var year=date.getFullYear()
	var month=date.getMonth()+1
	var day=date.getDate()

	return twoDigits(day) + "/" + twoDigits(month) + "/" + year;	
}

function GetTotalDays(date) 
{
	var hours = 1000*60*60;
	var days = hours*24;
	
	return parseInt((date / days), 10)
}

function GetAge(date) 
{
	var hours = 1000*60*60;
	var year = hours*24* 365;
	
	var y = parseInt((date / year), 10)
	date = date - year * y;
	
	var m = parseInt((date / year)*12, 10)

	if (m == 0)
		return y;

	return y +"."+m
}

function twoDigits(i)
{
	if (i < 10)
  		i = "0" + i

	return i;
}

function CalcWeeksOK(date)
{
	if (date == "")
		return true;
 	var today = new Date();
 	var lmp = ConvertStrToDate(date)

	days = GetTotalDays(today - lmp)
	if (days > 40*7 + 1)
		return false;
	else if (days < 0)
		return false;

	return true;
}

function IsDateOK(date)
{
	if (date == "")
		return true;
 	var today = new Date();
 	var d = ConvertStrToDate(date)

	if (today <=d )
		return false;
		
	return true;
}