diff --git a/README.md b/README.md
new file mode 100644
index 0000000..c32d931
--- /dev/null
+++ b/README.md
@@ -0,0 +1,7 @@
+Gruppe 14: SASSY
+
+WebServer starten:
+`php -qS localhost:8000`
+	
+WebServer (Debug) starten:
+`php -S localhost:8000`
\ No newline at end of file
diff --git a/files/lib/basic.js b/files/lib/basic.js
index f75096f..4a027cf 100644
--- a/files/lib/basic.js
+++ b/files/lib/basic.js
@@ -349,14 +349,7 @@ function form1(string) {
 
 
 async function getUserData(couchDB) {
-	let username = getURLArgsMap()["user"];
-	if (!username) {
-		if (debug && typeof (debug_username) == "string") {
-			username = debug_username;
-		} else {
-			return null;
-		}
-	}
+	let username = localStorage.getItem("user");
 	const res = await couchDB.get("users");
 	if (!res) return null;
 	const data = res[username];
diff --git a/files/login.html b/files/login.html
index 08ca1fb..a45742c 100644
--- a/files/login.html
+++ b/files/login.html
@@ -7,6 +7,7 @@
 <link rel="stylesheet" href="./lib/basic.css" />
 <script src="./auth.js"></script>
 <script src="./lib/basic.js"></script>
+
 <style>
 	* {
 		box-sizing: border-box;
@@ -98,6 +99,7 @@
 		autocomplete="username"
 		autocapitalize="off"
 		autocorrect="off"
+		onkeypress='if (event.key == "Enter") login()'
 		required
 		autofocus
 	/>
@@ -108,6 +110,7 @@
 		id="password"
 		name="password"
 		autocomplete="current-password"
+		onkeypress='if (event.key == "Enter") login()'
 		required
 	/>
 
@@ -141,11 +144,14 @@ async function login() {
 	if (user.password != password) {
 		return alert("Incorrect password!");
 	}
+	
+	localStorage.setItem("user", username);
+	
 	if (user.role === "student") {
-		location.href = "./student/uebersicht.html?user=" + username;
+		location.href = "./student/uebersicht.html";
 		return;
 	} else {
-		location.href = "./prof/uebersicht.html?user=" + username;
+		location.href = "./prof/uebersicht.html";
 		return;
 	}
 }
diff --git a/files/prof/auswertung.html b/files/prof/auswertung.html
index 0a3572a..77d30c4 100644
--- a/files/prof/auswertung.html
+++ b/files/prof/auswertung.html
@@ -103,7 +103,7 @@ button.navigation:hover {
 <div class="header_bar_1">
 	<div>
 		<div>
-			<button onclick="location.href = './uebersicht.html?user=' + userData.name;" class="navigation">Meine Kurse</button>
+			<button onclick="location.href = './uebersicht.html';" class="navigation">Meine Kurse</button>
 		</div>
 	</div>
 	<div><b>Auswertungen</b></div>
diff --git a/files/prof/kursAnzeige.html b/files/prof/kursAnzeige.html
index 8cda212..6580150 100644
--- a/files/prof/kursAnzeige.html
+++ b/files/prof/kursAnzeige.html
@@ -17,7 +17,7 @@ setUserData(couchDB);
 </head>
 <body>
 	<div class="header_bar_1">
-	<button class="back" onclick="location.href = './uebersicht.html?user=' + userData.name;">
+	<button class="back" onclick="location.href = './uebersicht.html';">
 		Übersicht
     </button>
 	<div>
diff --git a/files/prof/uebersicht.html b/files/prof/uebersicht.html
index cb58f49..acdd74a 100644
--- a/files/prof/uebersicht.html
+++ b/files/prof/uebersicht.html
@@ -20,7 +20,7 @@ setUserData(couchDB);
 		Meine Kurse
 	</div>
 	<div>
-		<button class="auswertung" onclick='location.href = "./auswertung.html?user=" + userData.name'>
+		<button class="auswertung" onclick='location.href = "./auswertung.html";'>
 			Auswertungen
 		</button>
 	</div>
diff --git a/files/student/kursAnzeige.html b/files/student/kursAnzeige.html
index d71ea24..1a48210 100644
--- a/files/student/kursAnzeige.html
+++ b/files/student/kursAnzeige.html
@@ -18,7 +18,7 @@
 <body>
   <div class="header_bar_1">
     <div>
-      <button onclick="location.href = './uebersicht.html?user=' + userData.name;" class="back">Meine
+      <button onclick="location.href = './uebersicht.html" class="back">Meine
         Kurse</button>
     </div>
     <div>
diff --git a/files/student/uebersicht.html b/files/student/uebersicht.html
index 80f66a8..6add110 100644
--- a/files/student/uebersicht.html
+++ b/files/student/uebersicht.html
@@ -208,7 +208,7 @@ async function startSurvey() {
 			users[userData.name].courses.push(code);
 		}
 		await couchDB.set("users", users);
-		location.href = "./umfrage.html?user=" + userData.name + ",course=" + code;
+		location.href = "./umfrage.html?course=" + code;
 	} else {
 		alert("Umfrage nicht gefunden!");
 	}
@@ -229,7 +229,7 @@ async function setCourseView() {
 		card.addEventListener("click", (e) => {
 			if (e.target.closest("button")) return;
 			location.href =
-				"./kursAnzeige.html?user=" + userData.name + ",course=" + courseId;
+				"./kursAnzeige.html?course=" + courseId;
 		});
 
 		const surveyUrl = (card.innerHTML = `
@@ -240,7 +240,7 @@ async function setCourseView() {
 </div>
 
 ${isExpired ? '': `
-<button class="action start" onclick='location.href = "./umfrage.html?user=${userData.name},course=${courseId.trim()}";'>
+<button class="action start" onclick='location.href = "./umfrage.html?course=${courseId.trim()}";'>
 	Umfrage Starten
 </button>`
 }
diff --git a/files/student/umfrage.html b/files/student/umfrage.html
index ba48839..0ea24bf 100644
--- a/files/student/umfrage.html
+++ b/files/student/umfrage.html
@@ -163,7 +163,7 @@ async function updateCourseAnswer(answer) {
 	return kurs;
 }
 function close_page() {
-	location.href = "./uebersicht.html?user=" + userData.name;
+	location.href = "./uebersicht.html";
 }
 
 function createNavBar(pos) {
@@ -287,7 +287,7 @@ async function onFinishEva() {
 	}
 }
 async function onEndEvent() {
-	location.href = "./uebersicht.html?user=" + userData.name;
+	location.href = "./uebersicht.html";
 }
 
 (async () => {
diff --git a/index.php b/index.php
index 63fdb29..86285e1 100644
--- a/index.php
+++ b/index.php
@@ -4,8 +4,12 @@ require_once './utils/couch.php';
 
 
 $path_info = new TurtlePathInfo();
-$path_info->content = "./files/";
-	
+$path_info->filesDir = "./files/";
+$path_info->contentDir = "./files/";
+$path_info->homeFile = "./files/START.html";
+$path_info->notFoundFile = "./files/NOT-FOUND.html";
+
+
 $url_obj = TurtleURLObject::create_from_server(false, false);
 
 if (str_starts_with($url_obj->url, "couchdb")) {
diff --git a/utils/url_handler.php b/utils/url_handler.php
index 410078a..a380a7b 100644
--- a/utils/url_handler.php
+++ b/utils/url_handler.php
@@ -1,17 +1,48 @@
 <?php
 
 class TurtlePathInfo {
-	public string $content;
+	public static function create_default(string $filesDir) :TurtlePathInfo {
+		$res = new TurtlePathInfo();
+		$res->filesDir = $filesDir;
+		$res->contentDir = "{$filesDir}content/";
+		$res->homeFile = "{$res->contentDir}HOME";
+		$res->notFoundFile = "{$res->contentDir}NOT-FOUND";
+		return $res;
+	}
+	
+	public string $filesDir;
+	public string $contentDir;
+	
+	public string $homeFile;
+	public string $notFoundFile;
 }
+
 class TurtleURLObject {
+	public static function parse_url_mark(array $urlParts) :object {
+		$res = (object) [];
+		if (count($urlParts) == 1) return $res;
+		foreach (explode('&', $urlParts[1]) as $part) {
+			$arr = explode('=', $part, 2);
+			$cnt = count($arr);
+			switch ($cnt) {
+				case 1:
+					$res->{$arr[0]} = 1;
+					break;
+				case 2:
+					$res->{$arr[0]} = $arr[1];
+					break;
+			}
+		}
+		return $res;
+	}
 	public static function create_from_server(bool $lowerCase = true, bool $alternativeURL = true) :TurtleURLObject {
 		$urlParts = explode('?',  trim($_SERVER['REQUEST_URI'], '/'));
-		$urlMark = _parseUrlMark($urlParts);
+		$urlMark = TurtleURLObject::parse_url_mark($urlParts);
 		$request = str_replace("..", ".", $urlParts[0]);
 		
 		if ($lowerCase) $request = strtolower($request);
 		if ($alternativeURL) $request = str_replace("-", "/", $request);
-		
+				
 		$res = new TurtleURLObject($request, $urlMark);
 		$res->method = $_SERVER['REQUEST_METHOD'];
 		$res->method_type = explode(',', $_SERVER['HTTP_ACCEPT'] ?? '');
@@ -32,116 +63,109 @@ class TurtleURLObject {
 		$bodyContent = file_get_contents("php://input");
 		return $bodyContent;
 	}
-	
-	public function get_html_file(string $file_path): string {
-		if (!file_exists($file_path)) {
-			return "Not found!";
-		} else {
-			return file_get_contents($file_path);
-		}
+	public function get_body_json() :mixed {
+		$res = json_decode($this->get_body_text());
+		return json_last_error() === JSON_ERROR_NONE ? $res: null;
 	}
 	public function send_text(string $text) :void {
-		header('Content-Type: text/plain');
+		$this->set_ext_header('txt');
 		echo $text;
 	}
 	public function send_json(mixed $data) :void {
-		header('Content-Type: application/json');
+		$this->set_ext_header('json');
 		echo json_encode($data);
 	}
-	public function send_image(string $path) :void {
+	
+	//send custom content
+	
+	public function send_file(string $path) :void {
 		$fileExt = pathinfo($path, PATHINFO_EXTENSION);
-		if ($fileExt === "ico") {
-			header("Cache-Control: no-cache, must-revalidate, max-age=0");
-			header("Content-Type: image/x-icon");
+		$fileExt = strtolower(ltrim($fileExt, '.'));
+		$this->set_ext_header($fileExt);
+		
+		if ($fileExt == "html") {
+			if (!is_file($path)) echo 'File not found!';
+			else echo $this->get_html_file($path);
 		} else {
-			header("Content-Type: image/$fileExt");
+			if (!is_file($path)) echo '';
+			else readfile($path);
 		}
-		readfile($path);
 	}
-	public function send_custom_file(string $path) :bool {
-		$fileExt = pathinfo($path, PATHINFO_EXTENSION);
-		if (isFileExtImage($fileExt)) {
-			$this->send_image($path);
-		} else if ($fileExt == "json") {
-			$content = file_get_contents($path);
-			if ($content == false) return false;
-			header('Content-Type: application/json');
-			echo $content;
-		} else if ($fileExt == "txt") {
-			$content = file_get_contents($path);
-			if ($content == false) return false;
-			$this->send_text($content);
-		} else if ($fileExt == "js") {
-			header('Content-Type: text/javascript; charset=utf-8');
-			echo file_get_contents($path);
-			return true;
-		} else if ($fileExt == "css") {
-			header("Content-Type: text/css");
-			echo file_get_contents($path);
-		} else if ($fileExt == "html") {
-			echo $this->get_html_file($path);
-		} else {
+	public function allow_ext_referer(string $ext) :bool {
+		$types = $this->method_type;
+		if (isFileExtImage($ext)) {
+			foreach ($types as $i) if (str_starts_with($i, 'image/')) return true;
 			return false;
+		} else if ($ext == 'js') {
+			if (sizeof($types) == 1 && $types[0] == "*/*") return true;
+			return false;
+		} else if ($ext == 'css') {
+			foreach ($types as $i) if ($i == 'text/css') return true;
+			return false;
+		} else {
+			return true;
+		}
+	}
+	public function set_ext_header(string $ext) :void {
+		if (isFileExtImage($ext)) {
+			if ($ext === "ico") {
+				header("Cache-Control: no-cache, must-revalidate, max-age=0");
+				header("Content-Type: image/x-icon");
+			} else {
+				header("Content-Type: image/$ext");
+			}
+			return;
+		}
+		switch ($ext) {
+			case 'html':
+				header('Content-Type: text/html'); break;
+			case 'json':
+				header('Content-Type: application/json'); break;
+			case 'css':
+				header("Content-Type: text/css"); break;
+			case 'js':
+				header('Content-Type: application/javascript; charset=utf-8'); break;
+			case 'md': case 'txt':
+				header('Content-Type: text/plain'); break;
+			case 'pdf':
+				header("Content-Type: application/$ext"); break;
+			default:
+				header('Content-Type: text/html'); break;
 		}
-		return true;
 	}
 	
-	public function is_image_request() :bool {
-		foreach ($this->method_type as $type) {
-			if (!str_starts_with($type, "image/")) return false;
-		}
-		return true;
-	}
+	//execution
 	
+	private function get_html_file(string $file_path): string {
+		return file_get_contents($file_path);
+	}
+	private function _get_path(string|null $path, string $filesDir = "") :string {
+		if ($path == null || is_file($path)) return $path;
+		if (is_file("$path.html")) return "$path.html";
+			
+		return $path;
+	}
 	public function handle_request(TurtlePathInfo $path_info): void {
 		$referer = $_SERVER['HTTP_REFERER'] ?? '';
 
-		$filePath = $path_info->content . $this->url;
-		
-		if (strlen($this->url) == 0) {
-			$filePath = "{$path_info->content}START.html";
-		}
-		
-		//-------------Image-Pages-------------------//
-		else if (
-			!empty($referer) && $this->is_image_request()
-		) {
-			if (file_exists($filePath)) {
-				$this->send_image($filePath);
-				return;
-			} else {
-				$filePath = NULL;
-			}
-		}
-		
-		//-------------HTML-Pages-------------------//
+		$filePath = $path_info->contentDir . $this->url;
+		if (strlen($this->url) == 0) $filePath = $path_info->homeFile;
 				
-		if ($filePath === NULL || !file_exists($filePath)) {
-			$filePath = "{$path_info->content}NOT-FOUND.html";
-			http_response_code(404);
+		$filePath = $this->_get_path($filePath, $path_info->filesDir);
+		if (!($this->allow_ext_referer(pathinfo($filePath, PATHINFO_EXTENSION)))) {
+			$filePath = null;
 		}
 		
-		$this->send_custom_file($filePath);
+		if ($filePath == null || !is_file($filePath)) {
+			http_response_code(404);
+			$filePath = $this->_get_path($path_info->notFoundFile, $path_info->filesDir);
+		}
+		
+		$this->send_file($filePath);
 	}
 }
 
-function _parseUrlMark($urlParts) :object {
-	$res = (object) [];
-	if (count($urlParts) == 1) return $res;
-	foreach (explode('&', $urlParts[1]) as $part) {
-		$arr = explode('=', $part, 2);
-		$cnt = count($arr);
-		switch ($cnt) {
-			case 1:
-				$res->{$arr[0]} = 1;
-				break;
-			case 2:
-				$res->{$arr[0]} = $arr[1];
-				break;
-		}
-	}
-	return $res;
-}
+
 function isFileExtImage(string $fileExt) :bool {
 	switch ($fileExt) {
 		case 'png':