Create user on first login

server/src/main/java/com/vpr/server/controller/UserController.java

@@ -84,6 +84,27 @@ public class UserController {
             @RequestParam String login,
             @RequestParam String password
     ) {
+        if(userRepository.findAllUsernames().length == 0){
+            byte[] salt = Hasher.GenerateSalt();
+            byte[] hash;
+            try {
+                hash = Hasher.HashPassword(password, salt);
+            } catch (NoSuchAlgorithmException | InvalidKeySpecException e) {
+                e.printStackTrace();
+                return new ResponseEntity<>("Fehler beim hashen", HttpStatus.INTERNAL_SERVER_ERROR);
+            }
+
+            User user = new User();
+            user.setName("Admin");
+            user.setForename(login);
+            user.setLogin(login);
+            user.setPassword(hash);
+            user.setSalt(salt);
+            user.setToken("");
+            user.setAdmin(true);
+
+            userRepository.save(user);
+        }
         System.out.println(login + " tries to login.");
         User user = userRepository.findByLogin(login);
         if (user == null) {