// These two functins take care of the
// navigation item images
function set_one_navi_image(imageid) {
	document.getElementById("content_left_item_" + imageid).style.backgroundImage="url(http://www.contactair-va.de/images/layout/bg_navi_item_"+imageid+"_on.png)";
}
function clear_one_navi_image(imageid) {
	document.getElementById("content_left_item_" + imageid).style.backgroundImage="url(http://www.contactair-va.de/images/layout/bg_navi_item_"+imageid+".png)";
}

// This function determnines the value of
// an array of radio buttons
function getRadioValue(argRadioButton) {
	for (var i=0; i < argRadioButton.length; i++) {
		if (argRadioButton[i].checked) {
			return argRadioButton[i].value;
		}
	}
	return null;
}

// This function sets a mouse down image
function setMouseDown(argButtonText) {
	document.getElementById("button" + argButtonText).src = 'http://www.contactair-va.de/images/buttons/' + argButtonText + "1.gif";
}
// This function sets a mouse up image
function setMouseUp(argButtonText) {
	document.getElementById("button" + argButtonText).src = 'http://www.contactair-va.de/images/buttons/' + argButtonText + "0.gif";
}


// This function checks if at least one
// item of a list of checkable elements
// is checked
function oneIsChecked(argCheckableElement) {
	var returnValue = false;
	for (var i = 0; i < argCheckableElement.length; i++) {
		if (argCheckableElement[i].checked) {
			returnValue = true;
		}
	}
	return returnValue;
}

// This function validates an eMail-address
function validateEmail(emailToCheck) {	
	var exclude=/[^@\-\.\w]|^[_@\.\-]|[\._\-]{2}|[@\.]{2}|(@)[^@]*\1/;
	var check=/@[\w\-]+\./;
	var checkend=/\.[a-zA-Z]{2,4}$/;
	
	if(((emailToCheck.search(exclude) != -1)||(emailToCheck.search(check)) == -1)||(emailToCheck.search(checkend) == -1)){
		return false;
	}
	else {
		return true;
	}
}

// This function validates a given filename to
// a list of allowed extensions.
function validateFileExtension(argFileName, argAllowedExtensions) {

	var fileExtension      = argFileName.substring(argFileName.lastIndexOf('.')+1).toLowerCase();
	var fileExtensionValid = false;
	
	
	for (i=0; i < argAllowedExtensions.length; i++) {

		if (fileExtension == argAllowedExtensions[i].toLowerCase()) {
			fileExtensionValid = true;
			break;
		}
	}	
		
	return fileExtensionValid;
}

// This function validates a Date
function validateDate(argDate) {

	var dateDay, dateMonth, dateYear, daysMonth, dateToCheckLen, dotCounter, i;
	
	dateLen=argDate.length;
	dotCounter = 0;
	
	// Find the number of dots
	for (i=0; i < dateLen; i++) {
		if (argDate.substring(i, i+1) == ".")
			dotCounter++;
	}

	// Get the Day, Month and Year values
	if (dateLen==10 && argDate.substring(2,3)=="." && argDate.substring(5,6)=="." && dotCounter==2) {
		dateDay	  = parseInt(argDate.substring(0,2),10);
		dateMonth = parseInt(argDate.substring(3,5),10);
		dateYear  = parseInt(argDate.substring(6,10),10);
	}
	else if (dateLen==8 && argDate.indexOf(".")== -1) {
		dateDay	  = parseInt(argDate.substring(0,2),10);
		dateMonth = parseInt(argDate.substring(2,4),10);
		dateYear  =	parseInt(argDate.substring(4,8),10);
	}
	else {
		return false
	}
	
	// Get the possible values for that date
	if (dateMonth==4 || dateMonth==6 || dateMonth==9 || dateMonth==11) {
		daysMonth=30;
	}
	else if (dateMonth==1 || dateMonth==3 || dateMonth==5 || dateMonth==7 || dateMonth==8 || dateMonth==10 || dateMonth==12) {
		daysMonth=31;
	}
	else if(dateMonth==2 && (dateYear%4==0 && (dateYear%100!=0 || dateYear%400==0))) {
		daysMonth=29;
	}
	else if(dateMonth==2 && (dateYear%4!=0 || (dateYear%100==0 && dateYear%400!=0))) {
		daysMonth=28;
	}
	
	// Now finally check the date
	if (dateDay>=1 && dateDay<=daysMonth && dateMonth>=1 && dateMonth<=12 && dateYear>=1900 && dateYear<=2999) {
		return true;
	}
	else {
		return false;
	}

}