var form_errmsg = '';
var reValidEmail = new RegExp('^[a-z0-9\.\_\%\+\-]+@([A-Z0-9-]+\.)+[a-z]{2,6}$', 'i');

function dummy(response) { }

function is_empty(str) {
	return (typeof(str) == 'undefined') || !str;
}

function is_radio(radio) {
	var ok = false;

	for (c = 0; c < radio.length; c++) {
		if (radio[c].checked) {
			ok = true;
		}
	}
	return ok;
}

function newsletterValidateForm(theForm) {
			if(!is_email(theForm.email.value)) {
				form_errmsg = form_errmsg + "\nMolimo vas da upisete vasu email adresu!";
				theForm.email.focus();
				return(-1);
			}
			return(0);
		}


function newsletterFormSubmit(form, divID, callback_f) {
	var errcode;
	if (errcode = newsletterValidateForm(form)) {
		alert(trim(form_errmsg));
		form_errmsg = '';
	} else {

		var params = Form.serialize(form);
		Form.disable(form);
		new Ajax.Updater(divID, form.action,
    		{ asynchronous:true,
      		  evalScripts:true,
	      	  onComplete: function(r) { Form.enable(form); callback_f(r.responseText); },
    	  	  parameters:params
    		}
		);
	}
}

/****** utility functions ********/

function is_email(str) {
	return reValidEmail.test(str);
}

function is_empty(str) {
	return (typeof(str) == 'undefined') || !str;
}

function ltrim(str) {
	return str.replace(/^\s*/, '');
}

function rtrim(str) {
	return str.replace(/\s*$/, '');
}

function trim(str) {
	return ltrim(rtrim(str));
}

function trim_all_elements(form) {
	var el = Form.getElements(form);
	for (var i = 0; i < el.length; i++) {
		if (el[i].type != 'file')
			el[i].value = trim(el[i].value);
	}
}