var USERNAME_MAX = 127;
var USERNAME_MIN = 6;
var PASSWORD_MAX = 127;
var EMAIL_MAX = 255;

var FIRST_NAME_MAX = 127;
var LAST_NAME_MAX = 127;
var FULL_NAME_MAX = 255;

var ADDRESS1_MAX = 127;
var ADDRESS2_MAX = 127;
var CITY_MAX = 127;
var STATE_MAX = 2;
var OTHER_STATE_MAX = 127;
var COUNTRY_MAX = 3;
var POSTCODE_MAX = 15;

var CREDIT_CARD_NAME_MAX = FULL_NAME_MAX;
var CREDIT_CARD_NUMBER_MAX = 31;
var CREDIT_CARD_CCV_MAX = 4;

var EMPTY_MESSAGE = "Missing required %s";
var LENGTH_MESSAGE = "%s must be between %s and %s characters";

function validate_string_not_empty ( str, message ) {
	if (str.length == 0) {
		alert (message);
		return false;
	}
	else return true;
}

function validate_string_size (str, min, max, message ) {
	if (str.length < min || str.length > max) {
		alert (message);
		return false;
	}
	else return true;
}

function validate_first_name(str) {
	name = "First Name";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, FIRST_NAME_MAX, sprintf(LENGTH_MESSAGE, name, 1, FIRST_NAME_MAX)) ) return false;
	return true;
}

function validate_last_name(str) {
	name = "Last Name";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, LAST_NAME_MAX, sprintf(LENGTH_MESSAGE, name, 1, LAST_NAME_MAX)) ) return false;
	return true;
}

function validate_username(str, name) {
	if (!name) name = "Username";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, USERNAME_MIN, USERNAME_MAX, sprintf(LENGTH_MESSAGE, name, USERNAME_MIN, USERNAME_MAX)) ) return false;
	return true;
}

function validate_screenname(str, name) {
	if (!name) name = "Screename";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, USERNAME_MAX, sprintf(LENGTH_MESSAGE, name, 1, USERNAME_MAX)) ) return false;
	return true;
}

function validate_email(str) {
	name = "E-mail";
	var reg1 = /(@.*@)|(\.\.)|(@\.)|(\.@)|(^\.)/; // not valid
	var reg2 = /^.+\@(\[?)[a-zA-Z0-9\-\.]+\.([a-zA-Z]{2,6}|[0-9]{1,3})(\]?)$/; // valid
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, EMAIL_MAX, sprintf(LENGTH_MESSAGE, name, 1, EMAIL_MAX)) ) return false;
	if ( !(!reg1.test(str) && reg2.test(str)) ) {
		alert("Invalid email address format");
		return false;
	}
	return true;
}

function validate_password(str) {
	name = "Password";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 6, PASSWORD_MAX, sprintf(LENGTH_MESSAGE, name, 6, PASSWORD_MAX)) ) return false;
	return true;
}

function validate_passwords(str1, str2) {
	name = "Username";
	if ( !(str1 == str2) ) {
		alert("Passwords do not match");
		return false;
	}
	if ( !validate_password(str1) ) return false;
	if ( !validate_password(str2) ) return false;
	return true;
}

function validate_address1(str) {
	name = "Address 1";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, ADDRESS1_MAX, sprintf(LENGTH_MESSAGE, name, 1, ADDRESS1_MAX)) ) return false;
	return true;
}

function validate_address2(str) {
	name = "Address 2";
	if ( !validate_string_size(str, 0, ADDRESS2_MAX, sprintf(LENGTH_MESSAGE, name, 1, ADDRESS2_MAX)) ) return false;
	return true;
}

function validate_city(str) {
	name = "City";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, CITY_MAX, sprintf(LENGTH_MESSAGE, name, 1, CITY_MAX)) ) return false;
	return true;
}

function validate_state(str) {
	name = "State";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, STATE_MAX, sprintf(LENGTH_MESSAGE, name, 1, STATE_MAX)) ) return false;
	return true;
}

function validate_country(str) {
	name = "Country";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, COUNTRY_MAX, sprintf(LENGTH_MESSAGE, name, 1, COUNTRY_MAX)) ) return false;
	return true;
}

function validate_postcode(str) {
	name = "Zipcode";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, POSTCODE_MAX, sprintf(LENGTH_MESSAGE, name, 1, POSTCODE_MAX)) ) return false;
	return true;
}

function validate_card_type(str) {
	name = "Credit Card Type";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( str!='001' && str!='002' && str!='003' && str!='004' ) {
		alert('Invalid credit card type');
		return false;
	}
	return true;
}

function validate_card_name(str) {
	name = "Credit Card Name";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, CREDIT_CARD_NAME_MAX, sprintf(LENGTH_MESSAGE, name, 1, CREDIT_CARD_NAME_MAX)) ) return false;
	return true;
}

function validate_card_number(str) {
	name = "Credit Card Number";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, CREDIT_CARD_NUMBER_MAX, sprintf(LENGTH_MESSAGE, name, 1, CREDIT_CARD_NUMBER_MAX)) ) return false;
	return true;
}

function validate_card_expiration(month, year) {
	name = "Credit Card Month";
	var today = new Date();
	x = today.getYear();
	var y = x % 100;
	y += (y < 38) ? 2000 : 1900;
	var today_year = y;
	var today_month = today.getMonth()+1;
	if (year < today_year || (year == today_year && month < today_month)) {
		alert('Invalid credit card expiration');
		return false;
	}
	return true;
}

function validate_card_ccv(str) {
	name = "Credit Card CCV Number";
	if ( !validate_string_not_empty(str, sprintf(EMPTY_MESSAGE, name)) ) return false;
	if ( !validate_string_size(str, 1, CREDIT_CARD_CCV_MAX, sprintf(LENGTH_MESSAGE, name, 1, CREDIT_CARD_CCV_MAX)) ) return false;
	return true;
}



function sprintf()
{
	if (!arguments || arguments.length < 1 || !RegExp)
	{
		return;
	}
	var str = arguments[0];
	var re = /([^%]*)%('.|0|\x20)?(-)?(\d+)?(\.\d+)?(%|b|c|d|u|f|o|s|x|X)(.*)/;
	var a = b = [], numSubstitutions = 0, numMatches = 0;
	while (a = re.exec(str))
	{
		var leftpart = a[1], pPad = a[2], pJustify = a[3], pMinLength = a[4];
		var pPrecision = a[5], pType = a[6], rightPart = a[7];
		
		//alert(a + '\n' + [a[0], leftpart, pPad, pJustify, pMinLength, pPrecision);

		numMatches++;
		if (pType == '%')
		{
			subst = '%';
		}
		else
		{
			numSubstitutions++;
			if (numSubstitutions >= arguments.length)
			{
				alert('Error! Not enough function arguments (' + (arguments.length - 1) + ', excluding the string)\nfor the number of substitution parameters in string (' + numSubstitutions + ' so far).');
			}
			var param = arguments[numSubstitutions];
			var pad = '';
			       if (pPad && pPad.substr(0,1) == "'") pad = leftpart.substr(1,1);
			  else if (pPad) pad = pPad;
			var justifyRight = true;
			       if (pJustify && pJustify === "-") justifyRight = false;
			var minLength = -1;
			       if (pMinLength) minLength = parseInt(pMinLength);
			var precision = -1;
			       if (pPrecision && pType == 'f') precision = parseInt(pPrecision.substring(1));
			var subst = param;
			       if (pType == 'b') subst = parseInt(param).toString(2);
			  else if (pType == 'c') subst = String.fromCharCode(parseInt(param));
			  else if (pType == 'd') subst = parseInt(param) ? parseInt(param) : 0;
			  else if (pType == 'u') subst = Math.abs(param);
			  else if (pType == 'f') subst = (precision > -1) ? Math.round(parseFloat(param) * Math.pow(10, precision)) / Math.pow(10, precision): parseFloat(param);
			  else if (pType == 'o') subst = parseInt(param).toString(8);
			  else if (pType == 's') subst = param;
			  else if (pType == 'x') subst = ('' + parseInt(param).toString(16)).toLowerCase();
			  else if (pType == 'X') subst = ('' + parseInt(param).toString(16)).toUpperCase();
		}
		str = leftpart + subst + rightPart;
	}
	return str;
}