// JavaScript Document from Grig®I

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

function isEmpty(string) 
{
	var str = string.toString();
	if(string.length == 0)
		return true;
	else
		return false;
}

function isValidEmail(string) 
{
	if (string.search(/^\w+((-\w+)|(\.\w+))*\@[A-Za-z0-9]+((\.|-)[A-Za-z0-9]+)*\.[A-Za-z0-9]+$/) != -1)
		return true;
	else
		return false;
}

function isAlphanumeric(string)
{
	if(string.search(/^[a-zA-Z0-9]+$/) == -1 )
		return true;	
	else
		return false;
}

function checkSearch(searchForm) {
	var keyword = searchForm.keyword;
	
	if (isEmpty(keyword.value)) {
		alert('Required to fill !');
		keyword.focus();
		return false;
	}
	return true;
}

function checkLogin(loginForm) {
	var username = loginForm.username;
	var password = loginForm.password;
	
	if (isEmpty(username.value) || isAlphanumeric(username.value) || username.value.length < 4) {
		alert('Username is a required field, min. 4 alphanumeric characters !');
		username.focus();
		return false;
	}
	
	if (isEmpty(password.value) || isAlphanumeric(password.value) || password.value.length < 6) {
		alert('Password is a required field, min. 6 alphanumeric characters !');
		password.focus();
		return false;
	}
	return true;
}

function checkSignup(signupForm) {
	var nickname = signupForm.nickname;
	var username = signupForm.username;
	var password = signupForm.password;

	if (isEmpty(nickname.value) || isAlphanumeric(nickname.value) || nickname.value.length < 4) {
		alert('Nickname is a required field, min. 4 alphanumeric characters !');
		nickname.focus();
		return false;
	}
	if (isEmpty(username.value) || isAlphanumeric(username.value) || username.value.length < 4) {
		alert('Username is a required field, min. 4 alphanumeric characters !');
		username.focus();
		return false;
	}
	if (isEmpty(password.value) || isAlphanumeric(password.value) || password.value.length < 4) {
		alert('Password is a required field, min. 4 alphanumeric characters !');
		password.focus();
		return false;
	}
	window.open('','MYWINDOW','width=680,height=500,toolbar=no,statusbar=no');
	return true;
}