// Controllo che il valore immesso in una form sia in formato Data Europeo

function checkeurodate(object_value)

    {
    //Returns true if value is a eurodate format or is NULL
    //otherwise returns false   

 //   if (object_value.length == 0)
  //      return true;

    //Returns true if value is a date in the dd/mm/yyyy format
        isplit = object_value.indexOf('/');

        if (isplit == -1 || isplit == object_value.length)
                return false;

    sDay = object_value.substring(0, isplit);

        isplit = object_value.indexOf('/', isplit + 1);

        if (isplit == -1 || isplit == object_value.length)
                return false;

    sMonth = object_value.substring((sDay.length + 1), isplit);

        sYear = object_value.substring(isplit + 1);

        if (!checkinteger(sMonth)) //check month
                return false;
                //alert("qui");
        else if (!checkrange(sMonth, 1, 12)) // check month
                return false;
                //alert("quo");
        else if (!checkinteger(sYear)) //check year
                return false;
                //alert("qua");
        else if (!checkrange(sYear, 1900, null)) //check year
                return false;
                //alert("que");
        else if (!checkinteger(sDay)) //check day
                return false;
                //alert("quu");
        else if (!checkday(sYear, sMonth, sDay)) //check day
                return false;
        else
                return true;
    }

function checkeurodateshort(object_value)
{
    //Returns true if value is a eurodate format or is NULL
    //otherwise returns false   

 //   if (object_value.length == 0)
  //      return true;

    //Returns true if value is a date in the dd/mm/yyyy format
    isplit = object_value.indexOf('/');

    if (isplit == -1 || isplit == object_value.length)
            return false;
    //isplit = object_value.indexOf('/', isplit + 1);
    if (isplit == -1 || isplit == object_value.length)
            return false;

    sMonth = object_value.substring(0, isplit);
	if(sMonth.length<2){
		return false;
	}

    sYear = object_value.substring(isplit + 1);

    if (!checkinteger(sMonth)) //check month
            return false;
    else if (!checkrange(sMonth, 1, 12)) // check month
            return false;
    else if (!checkinteger(sYear)) //check year
            return false;
    else if (!checkrange(sYear, 1900, null)) //check year
            return false;
    else
			return true;
}

function checkday(checkYear, checkMonth, checkDay)
    {
//alert(checkDay+checkMonth+checkYear);
        maxDay = 31;

        if (checkMonth == 4 || checkMonth == 6 || checkMonth == 9 || checkMonth == 11)
                maxDay = 30;
        else if (checkMonth == 2)
        {
                if (checkYear % 4 > 0)
                        maxDay = 28;
                else if (checkYear % 100 == 0 && checkYear % 400 > 0)
                        maxDay = 28;
                else
                        maxDay = 29;
        }
        return checkrange(checkDay, 1, maxDay); //check day
    }



function checkinteger(object_value)
    {
    //Returns true if value is a number or is NULL
    //otherwise returns false   
//alert(object_value);
    if (object_value.length == 0)
        return true;

    //Returns true if value is an integer defined as
    //   having an optional leading + or -.
    //   otherwise containing only the characters 0-9.
        var decimal_format = ".";
        var check_char;

    //The first character can be + -  blank or a digit.
        check_char = object_value.indexOf(decimal_format)
    //Was it a decimal?
    if (check_char < 1)
        return checknumber(object_value);
    else
        return false;
    }



function numberrange(object_value, min_value, max_value)
    {
    // check minimum
    if (min_value != null)
        {
        if (object_value < min_value)
                return false;
        }

    // check maximum
    if (max_value != null)
        {
        if (object_value > max_value)
                return false;
        }
        
    //All tests passed, so...
    return true;
    }



function checknumber(object_value)
    {
    //Returns true if value is a number and  is not NULL
    //otherwise returns false   

// controllo che non siano null
    if (object_value.length == 0)
        return false;

    //Returns true if value is a number defined as
    //   having an optional leading + or -.
    //   having at most 1 decimal point.
    //   otherwise containing only the characters 0-9.
        var start_format = " .+-0123456789";
        var number_format = " .0123456789";
        var check_char;
        var decimal = false;
        var trailing_blank = false;
        var digits = false;

    //The first character can be + - .  blank or a digit.
        check_char = start_format.indexOf(object_value.charAt(0))

    //Was it a decimal?
        if (check_char == 1)
            decimal = true;
        else if (check_char < 1)
                return false;
        
        //Remaining characters can be only . or a digit, but only one decimal.
        for (var i = 1; i < object_value.length; i++)
        {
                check_char = number_format.indexOf(object_value.charAt(i))
                if (check_char < 0)
                        return false;
                else if (check_char == 1)
                {
                        if (decimal)            // Second decimal.
                                return false;
                        else
                                decimal = true;
                }
                else if (check_char == 0)
                {
                        if (decimal || digits)  
                                trailing_blank = true;
        // ignore leading blanks

                }
                else if (trailing_blank)
                        return false;
                else
                        digits = true;
        }       
    //All tests passed, so...
    return true
    }





function checkrange(object_value, min_value, max_value)
    {
    //if value is in range then return true else return false

    if (object_value.length == 0)
        return true;


    if (!checknumber(object_value))
        {
        return false;
        }
    else
        {
        return (numberrange((eval(object_value)), min_value, max_value));
        }
        
    //All tests passed, so...
    return true;
    }