/*
*	Author:		Tim Alstadt
*	Company:		Eye-Site.nl Internet!
*	Date:			June, 5th 2009
*
*	This javascript file contains a function to perform several checks on html form fields to validate the data entered by the user.
*	
*	You can have form fields automaticly  checked by adding the following markers to the objects classnames:
*	check_notempty		Verifies that the form field is not empty.
*	check_email			Verifies that a valid email address is entered.
*	check_numeric			Verifies that a numeric value is entered.
*	check_url				Verifies that a valid url is entered (including http://)
*	
*	Additionally, add a title attribute to describe the form field. This title is used in the error message.
*
*	Example:
*		<input name="frm_email" type="text" class="check_notempty" title="email address">
*	This field will be checked for a valid email address.
*
*	To activate the validation routine, add the following attribute to your <form> element:
*		onsubmit='javascript: return checkForm(this);'
*	So that your complete form element looks like this:
*		<form name='frm_edit_details' action='?save' method='post' onsubmit='javascript: return checkForm(this);'>
*
*/

function IsNumeric(txt) {
	var ValidChars = "0123456789.";
	var IsNumber=true;
	var Char;

	for (y = 0; y < txt.length && IsNumber == true; y++) {
		Char = txt.charAt(y);
		if (ValidChars.indexOf(Char) == -1) {
			IsNumber = false;
		}
	}
	return IsNumber;
}

function elevenCheck(txt) {
	txt = txt.replace(/\D/, "");
	len = txt.length;
	var som=0;

	for (x=1; x<10; x++) {
		getal=txt.charAt(x-1);
		som+=getal*(10-x);
	} 

	if (som % 11==0 && len==9) {
		return true;
	} else {
		return false;
	}
	return false;
}

function checkForm(form) {
	var emailcheck =/^([\w-]+(?:\.[\w-]+)*)@((?:[\w-]+\.)*\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/i
	var urlcheck = /(http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/
	
	for (i = 0; i < form.elements.length; i++) {
		if (form.elements[i].className.search('check_email') != -1) {
			if (form.elements[i].value.length == 0 || !emailcheck.test(form.elements[i].value)) {
				window.alert('Het veld \'' + form.elements[i].title + '\' bevat geen geldig e-mailadres, controleer dit en probeer het nogmaals.');
				form.elements[i].focus();
				form.elements[i].select();
				return false;
			}
		}

		if (form.elements[i].className.search('check_url') != -1) {
			if (form.elements[i].value.length == 0 || !urlcheck.test(form.elements[i].value)) {
				window.alert('Het veld \'' + form.elements[i].title + '\' bevat geen geldig internetadres, controleer dit en probeer het nogmaals.');
				form.elements[i].focus();
				form.elements[i].select();
				return false;
			}
		}

		if (form.elements[i].className.search('check_numeric') != -1) {
			if (form.elements[i].value.length == 0 || !IsNumeric(form.elements[i].value)) {
				window.alert('Het veld \'' + form.elements[i].title + '\' moet numeriek zijn, controleer dit en probeer het nogmaals.');
				form.elements[i].focus();
				if(form.elements[i].tagName.toUpperCase() != 'SELECT') form.elements[i].select();
				return false;
			}
		}

		if (form.elements[i].className.search('check_notempty') != -1) {
			if (form.elements[i].value.length == 0) {
				window.alert('Het veld \'' + form.elements[i].title + '\' is niet ingevuld, controleer dit en probeer het nogmaals.');
				form.elements[i].focus();
				if(form.elements[i].tagName.toUpperCase() != 'SELECT') form.elements[i].select();
				return false;
			}
		}

		if (form.elements[i].className.search('check_eleven') != -1) {
			//window.alert(form.elements[i].title);
			//if (!elevenCheck(form.elements[i].value)) {
			if (!elevenCheck(form.elements[i].value)) {
				window.alert('Het veld \'' + form.elements[i].title + '\' bevat een ongeldige waarde (11 proef faalt), controleer dit en probeer het nogmaals.');
				form.elements[i].focus();
				if(form.elements[i].tagName.toUpperCase() != 'SELECT') form.elements[i].select();
				return false;
			}
		}
	}

	return true;
}