function check_address(form) {
	if (isBlank(form.email, "Please fill in an email address.")) { return false; }
	if (!isValidAddress(form.email.value)) {
		alert("Please enter a valid e-mail address.");
		form.email.focus();
		form.email.select();
		return false;
	}
	
	return true;
}

function check_contact(form) {
	if (isBlank(form.first_name, "Please enter your first name")) { return false; }
	if (isBlank(form.last_name, "Please enter your last name")) { return false; }	
	if (isBlank(form.email, "Please fill in an email address.")) { return false; }
	if (!isValidAddress(form.email.value)) {
		alert("Please enter a valid e-mail address.");
		form.email.focus();
		form.email.select();
		return false;
	}
	
	return true;
}

function check_iaf(form) {
	if (isBlank(form.company, "Please enter your company.")) { return false; }
	if (isBlank(form.first_name, "Please enter your first name.")) { return false; }
	if (isBlank(form.last_name, "Please enter your last name.")) { return false; }
	if (isBlank(form.phone, "Please enter your phone number.")) { return false; }
	if (isBlank(form.assistance, "Please enter the type of assistance needed.")) { return false; }
	
	return true;
}

function check_laf(form) {
	if (isBlank(form.company, "Please enter your company.")) { return false; }
	if (isBlank(form.first_name, "Please enter your first name.")) { return false; }
	if (isBlank(form.last_name, "Please enter your last name.")) { return false; }
	if (isBlank(form.phone, "Please enter your phone number.")) { return false; }
	if (isBlank(form.assistance, "Please enter the type of assistance needed.")) { return false; }
	
	return true;
}

function isBlank(obj, message) {
	if (obj.value == "") {
		alert(message);
		obj.focus();
		return true;
	}
	
	return false;
}

function isValue(obj, value, message) {
	if (obj.value == value) {
		alert(message);
		obj.focus();
		return true;
	}
	
	return false;
}

function isDateFormat(date) {	
		var d1 = date.split("-");	
		if ((d1.length < 3 || isNaN(d1[0]) || isNaN(d1[1]) || isNaN(d1[2]))) {		
			return false;
		}
		
		//conform to javascript date standards
		d1[1] = d1[1] - 1;
		d1[2] = get_full_year(d1[2]);
		
		if (!isValidDate(d1[1], d1[0], d1[2])) {
			return false;
		}
		
		return true;
}

function isValidAddress(addr) {
	index1 = addr.indexOf("@");
	if (index1 <= 0) {
		return false;
	}
	index2 = addr.indexOf(".", index1);
	if (index2 < index1) {
		return false;
	}
	
	//must be at least a period and 2 characters at the end
	if (index2 == addr.length-1 || index2 == addr.length-2) {
		return false;
	}
	return true;
}

function isValidDate(month, day, year) {
	var numDaysInMonths = new Array(31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31); 
	
	if (month < 0 || month > 11) {
		return false;
	}
	
	if (day < 1 || day > numDaysInMonths[month]) {
		return false;
	}else if (month == 2 && day == 29 && ((year%4) != 0 || (year%100) == 0)) {
		return false;
	}
	
	if (year >= 2100 || year < 1900) {
		return false;
	}
	return true;
}