function checkEmail(value) {
	var email_a = value.split('@');
	if (email_a.length == 2) {
		email_a = email_a[1].split('.');
		if (email_a.length == 2) return true;
	}
	return false;
}

function checkParam(form, msg, elemName, property) {
	if (!form.elements[elemName][property]) {
		alert(msg);
		form.elements[elemName].focus();
	} else {
        if ((elemName == 'email') && !checkEmail(form.elements[elemName][property])) {
		  alert(msg);
		  form.elements[elemName].focus();
        } return true;
    }	
	return false;
}

function checkFormParams(form, fields) {
    if (!fields) {
        fields = [
            {text:'Введите свое имя!', name:'name'},
            {text:'Введите свой контактный телефон!', name:'phone'},
            {text:'Не введен email, или неверный формат!', name:'email'},
            {text:'Оставьте свои пожелания!', name:'description'}
        ]
    }
    
    for (var i in fields) {
        var item = fields[i];
        if (form.elements[item.name]) {
        	if (!checkParam(form, item.text, item.name, item.property?item.property:'value'))
                return false;
        }
    }
    return true;
}