var count = 0;
function showAdvertising() {	
	if (count == 7) {
		return;
	}
	count++;
	if(document.getElementById('nl').style.visibility == 'visible') {	
		document.getElementById('nl').style.visibility = 'hidden';
	} else {	
		document.getElementById('nl').style.visibility = 'visible';
	}
	setTimeout("showAdvertising()", 350);
}

function onChangeDay() {
	if (document.datecreate.day.value.length == 2) {
		document.datecreate.month.focus();
	}
}

function onChangeMonth() {
	if (document.datecreate.month.value.length == 2) {
		document.datecreate.year.focus();
	}
}

function onChangeYear() {
	if (document.datecreate.year.value.length == 4) {
		document.datecreate.hour.focus();
	}
}

function onChangeHour() {
	if (document.datecreate.hour.value.length == 2) {
		document.datecreate.minute.focus();
	}
}

function onChangeMinute() {
	if (document.datecreate.minute.value.length == 2) {
		document.datecreate.club.focus();
	}
}

/* highlight effect
 * for menu
 * @params elementID: id of the element that the mouse is over
 *         color: color for the effect
*/
function menuOverTd(elementID, color) {
	overTd("menu", elementID, color);

}

/* function to build a mail adress
 * @params account account of a domain to send the mail
 */
function buildMailAdress(account) {	
	domain = "djlamboo";
	tld = "de";
	location.href = "mailto:" + account + "@" + domain + "." +tld;
}

/* function checks all inputfields of contact form
 * returns true, if all inputfields are filled and 
 * email adress valid
 * otherwise returns false
 */
function checkInput() {
	if (document.getElementById("from").value == "") {
		alert("Bitte Absender (email-Adresse) eingeben!");
		document.getElementById("from").focus();
		return false;
	}
	
	//check emailadress
	if (!checkEmailAdress(document.getElementById("from").value)) {
		alert("Bitte gültigen Absender (email-Adresse) eingeben!");
		document.getElementById("from").focus();
		return false;
	}	
	
	if (document.getElementById("subject").value == "") {
		alert("Bitte Betreff eingeben!");
		document.getElementById("subject").focus();
		return false;
	}
	
	if (document.getElementById("etext").value == "") {
		alert("Bitte Text eingeben!");
		document.getElementById("etext").focus();
		return false;
	}
	
	return true;
	
}

/* function checks if an email-adress
 * contains a "@" and "."
 * @params email email adress to check
 */
function checkEmailAdress(email) {
	//check email adress
	at = email.indexOf("@");
	if (at == -1 || at != email.lastIndexOf("@")) {
		//more than one "@"
		return false;
	} else {
		dot = email.lastIndexOf(".");
		if (dot == -1 || dot <= at) {
			//error
			return false;
		}	
	}
	return true;
}

/** function checks if all needed inputs in date create 
 *  are set and if date and time are valid
 *  return true or false
 */
function checkDateCreateInput() {
	//check date
	day = document.getElementById("day").value;
	if (day == "") {
		alert("Bitte Tag eingeben!");
		document.getElementById("day").focus();
		return false;
	}	
	if (day.length < 2) {
		alert("Bitte Tag zweistellig eingeben!");
		document.getElementById("day").focus();
		return false;
	}
	
	month = document.getElementById("month").value;		
	if (month == "") {
		alert("Bitte Monat eingeben!");
		document.getElementById("month").focus();
		return false;
	}	
	if (month.length < 2) {
		alert("Bitte Monat zweistellig eingeben!");
		document.getElementById("month").focus();
		return false;
	}
	month--;
	
	
	year = document.getElementById("year").value;
	if (year == "") {
		alert("Bitte Jahr eingeben!");
		document.getElementById("year").focus();
		return false;
	}
	if (year.length < 4) {
		alert("Bitte Jahr vierstellig eingeben!");
		document.getElementById("year").focus();
		return false;
	}
	
	
	//check if date is valid
	curDate = new Date (year, month, day);	
	//alert(curDate.getFullYear() + " " + curDate.getMonth() + " " + curDate.getDay());
	if (curDate.getFullYear() != year || curDate.getMonth() != month || curDate.getDate() != day) {
		alert("Bitte gültiges Datum eingeben!");
		document.getElementById("day").focus();
		return false;
	}
	
	
	//check time
	hour = document.getElementById("hour").value;
	minu = document.getElementById("minute").value;
	if ((hour == "" && minu != "") || (hour != "" && minu == "")) {	
		alert("Bitte gültige Zeit eingeben!");
		document.getElementById("hour").focus();
		return false;
	}
	
	//check if time is valid
	if (hour != "" && minu != "") {
		if (hour > 23 || hour < 0 || minu > 59 || minu < 0) {
			alert("Bitte gültige Zeit eingeben!");
			document.getElementById("hour").focus();
			return false;		
		}
		if (minu.length < 2) {
			alert("Bitte Minuten zweistellig eingeben!");
			document.getElementById("minute").focus();
			return false;	
		}
	}
	
	if (document.getElementById("club").value == "") {
		alert("Bitte Club eingeben!");
		document.getElementById("club").focus();
		return false;
	}
	
	return true;
}

/* popup to confirm given text
*  @params: text that has to confirmed
*  @return: true if "ok", false if "cancel"
*/
function popupToConfirm(text) {
	//popup mit ok abbrechen buttons
	return false;
}