//Create a boolean variable to check for a valid IE instance.
var xmlhttp = false;

//Check if we are using IE.
try {
	//If the javascript version is greater than 5.
	xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
} catch (e) {
	//If not, then use the older active x object.
	try {
		//If we are using IE.
		xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
	} catch (E) {
		//Else we must be using a non-IE browser.
		xmlhttp = false;
	}
}

//If we are using a non-IE browser, create a JavaScript instance of the object.
if (!xmlhttp && typeof XMLHttpRequest != 'undefined') {
	xmlhttp = new XMLHttpRequest();
}
	
function displayMedium (gallery, file, e){
		
	//The location we are loading the page into.
	var objID = "view_medium";
	
	var theextrachar = e.which;
	
		theextrachar = e.keyCode;
	if (theextrachar == undefined){
	}

	//Take into account the backspace.
	if (theextrachar == 8){
		if (file.length == 1){
			var serverPage = "view_medium.php";
		} else {
			var serverPage = "view_medium.php" + "?gallery=" + gallery + "&filename=" + file.substr (0, (file.length -1));
		}
	} else {
		var serverPage = "view_medium.php" + "?gallery=" + gallery + "&filename=" + file + String.fromCharCode (theextrachar);
	}
	
	var obj = document.getElementById(objID);
	xmlhttp.open("GET", serverPage);
	xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
			obj.innerHTML = xmlhttp.responseText;
		}
	}
	xmlhttp.send(null);
}
function closeLarge () {
	var objID = "view_large";
	var obj = document.getElementById(objID);
	obj.style.visibility = "hidden";
	var screen = document.getElementById("screen");
	screen.style.visibility ="hidden";
}

function displayLarge (gallery, file, e){
	
	//The location we are loading the page into.
	var objID = "view_large";
	var obj = document.getElementById(objID);
	obj.style.visibility = "visible";
	var screen = document.getElementById("screen");
	screen.style.visibility ="visible";
	
	var theextrachar = e.which;
	
		theextrachar = e.keyCode;
	if (theextrachar == undefined){
	}

	//Take into account the backspace.
	if (theextrachar == 8){
		if (file.length == 1){
			var serverPage = "view_large.php";
		} else {
			var serverPage = "view_large.php" + "?gallery=" + gallery + "&filename=" + file.substr (0, (file.length -1));
		}
	} else {
		var serverPage = "view_large.php" + "?gallery=" + gallery + "&filename=" + file + String.fromCharCode (theextrachar);
	}
	
	xmlhttp.open("GET", serverPage);
	xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
			obj.innerHTML = xmlhttp.responseText;
		}
	}
	xmlhttp.send(null);
}

function ChangeImage(image, file) {
	image.src = file;
}

function deleteImage (gallery, file, e){
	
	//The location we are loading the page into.
	var objID = "messagebox";
	var obj = document.getElementById(objID);
	obj.style.visibility = "visible";
	
	var theextrachar = e.which;
	
		theextrachar = e.keyCode;
	if (theextrachar == undefined){
	}

	//Take into account the backspace.
	if (theextrachar == 8){
		if (file.length == 1){
			var serverPage = "deleteimage.php";
		} else {
			var serverPage = "deleteimage.php" + "?gallery=" + gallery + "&filename=" + file.substr (0, (file.length -1));
		}
	} else {
		var serverPage = "deleteimage.php" + "?gallery=" + gallery + "&filename=" + file + String.fromCharCode (theextrachar);
	}
	
	xmlhttp.open("GET", serverPage);
	xmlhttp.onreadystatechange = function() {
		if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
			obj.innerHTML = xmlhttp.responseText;
		}
	}
	xmlhttp.send(null);
}

function confirmDelete (gallery, filename) {
	var answer = confirm("Delete image from gallery?")
	if (answer){
		delete_img_url = "./deleteimage.php?gallery=" + gallery + "&filename=" + filename;
		window.location = delete_img_url;
	}
}
function confirmDeleteGallery (gallery) {
	var answer = confirm("Delete all images in this gallery?")
	if (answer){
		delete_img_url = "./deletegallery.php?gallery=" + gallery;
		window.location = delete_img_url;
	}
}