(function () {
  const AUTH_STORAGE_KEY = "loremIpsumAuth";

  function readAuth() {
    const raw = localStorage.getItem(AUTH_STORAGE_KEY);
    if (!raw) {
      return null;
    }

    try {
      const parsed = JSON.parse(raw);
      if (!parsed.username || !parsed.password) {
        return null;
      }
      return parsed;
    } catch {
      return null;
    }
  }

  function saveAuth(username, password) {
    localStorage.setItem(
      AUTH_STORAGE_KEY,
      JSON.stringify({ username: username, password: password }),
    );
  }

  function clearAuth() {
    localStorage.removeItem(AUTH_STORAGE_KEY);
  }

  function updateHeaderUsername() {
    const usernameDisplay = document.getElementById("username-display");
    const navbarLogin = document.getElementById("navbar-login");
    const auth = readAuth();

    if (usernameDisplay) {
      usernameDisplay.textContent = auth ? "User: " + auth.username : "User: Guest";
    }

    if (navbarLogin) {
      navbarLogin.textContent = auth ? auth.username : "Login / Registrieren";
    }
  }

  function setFeedback(message, type) {
    const feedback = document.getElementById("auth-feedback");
    if (!feedback) {
      return;
    }

    feedback.className = "alert alert-" + type;
    feedback.textContent = message;
    feedback.classList.remove("d-none");
  }

  function updateSessionBox() {
    const sessionText = document.getElementById("current-session-text");
    const logoutButton = document.getElementById("logout-button");
    const deleteAccountButton = document.getElementById("delete-account-button");
    const currentSessionBox = document.getElementById("current-session-box");
    const authFormsRow = document.getElementById("auth-forms-row");

    if (!sessionText || !logoutButton || !deleteAccountButton || !currentSessionBox || !authFormsRow) {
      return;
    }

    const auth = readAuth();
    if (auth) {
      sessionText.textContent = "Eingeloggt als " + auth.username + ".";
      logoutButton.disabled = false;
      deleteAccountButton.disabled = false;
      currentSessionBox.classList.remove("d-none");
      authFormsRow.classList.add("d-none");
    } else {
      sessionText.textContent = "Nicht eingeloggt.";
      logoutButton.disabled = true;
      deleteAccountButton.disabled = true;
      currentSessionBox.classList.add("d-none");
      authFormsRow.classList.remove("d-none");
    }
  }

  function getUserService() {
    if (!window.config || !window.UserService) {
      return null;
    }

    return new window.UserService(window.config);
  }

  async function handleLoginSubmit(event) {
    event.preventDefault();

    const userService = getUserService();
    if (!userService) {
      setFeedback("User-Service konnte nicht geladen werden.", "danger");
      return;
    }

    const usernameInput = document.getElementById("login-username");
    const passwordInput = document.getElementById("login-password");
    const username = usernameInput.value.trim();
    const password = passwordInput.value.trim();

    if (!username || !password) {
      setFeedback("Bitte Username und Passwort eingeben.", "warning");
      return;
    }

    const result = await userService.getUser(username, password);
    if (result.ok) {
      saveAuth(username, password);
      setFeedback("Login erfolgreich.", "success");
      updateSessionBox();
      updateHeaderUsername();
      setTimeout(function() {
        if (typeof window.loadPage === "function") {
          window.loadPage("home", "nav-home");
        }
      }, 500);
      return;
    }

    if (result.status === 401) {
      setFeedback("Login fehlgeschlagen: Username oder Passwort ist falsch.", "danger");
      return;
    }

    setFeedback("Login fehlgeschlagen (Status " + result.status + ").", "danger");
  }

  async function handleRegisterSubmit(event) {
    event.preventDefault();

    const userService = getUserService();
    if (!userService) {
      setFeedback("User-Service konnte nicht geladen werden.", "danger");
      return;
    }

    const usernameInput = document.getElementById("register-username");
    const username = usernameInput.value.trim();

    if (!username) {
      setFeedback("Bitte einen Username eingeben.", "warning");
      return;
    }

    const result = await userService.postUser(username);
    if (result.ok && result.body) {
      const createdName = result.body.name || username;
      const createdPassword = result.body.password || "";

      saveAuth(createdName, createdPassword);
      updateSessionBox();
      updateHeaderUsername();

      // Modal mit Daten füllen und anzeigen
      const modalUsername = document.getElementById("modal-username");
      const modalPassword = document.getElementById("modal-password");
      if (modalUsername) modalUsername.textContent = createdName;
      if (modalPassword) modalPassword.textContent = createdPassword;

      const passwordModalElement = document.getElementById("password-modal");
      if (passwordModalElement) {
        const passwordModal = new window.bootstrap.Modal(passwordModalElement);
        
        // Listener für Modals-Schließen: zur Startseite navigieren
        passwordModalElement.addEventListener("hidden.bs.modal", function handleClose() {
          if (typeof window.loadPage === "function") {
            window.loadPage("home", "nav-home");
          }
          passwordModalElement.removeEventListener("hidden.bs.modal", handleClose);
        });

        passwordModal.show();
      } else {
        // Fallback wenn Modal nicht gefunden
        setFeedback(
          "Account erstellt. Username: " + createdName + ", Passwort: " + createdPassword,
          "success",
        );
        setTimeout(function() {
          if (typeof window.loadPage === "function") {
            window.loadPage("home", "nav-home");
          }
        }, 1500);
      }

      const loginUsernameInput = document.getElementById("login-username");
      const loginPasswordInput = document.getElementById("login-password");
      if (loginUsernameInput && loginPasswordInput) {
        loginUsernameInput.value = createdName;
        loginPasswordInput.value = createdPassword;
      }

      return;
    }

    if (result.status === 400) {
      const errorMessage = result.body && result.body.message
        ? result.body.message
        : "Dieser Username existiert bereits.";
      setFeedback(errorMessage, "danger");
      return;
    }

    setFeedback(
      "Account konnte nicht erstellt werden (Status " + result.status + ").",
      "danger",
    );
  }

  function handleLogout() {
    clearAuth();
    setFeedback("Du wurdest ausgeloggt.", "info");
    updateSessionBox();
    updateHeaderUsername();
  }

  async function handleDeleteAccount() {
    const auth = readAuth();
    if (!auth) {
      setFeedback("Du bist nicht eingeloggt.", "warning");
      return;
    }

    const wantsDelete = window.confirm(
      "Möchtest du den Account \"" + auth.username + "\" wirklich löschen?",
    );
    if (!wantsDelete) {
      return;
    }

    const userService = getUserService();
    if (!userService) {
      setFeedback("User-Service konnte nicht geladen werden.", "danger");
      return;
    }

    const result = await userService.deleteUser(auth.username, auth.password);
    if (result.ok) {
      clearAuth();
      updateSessionBox();
      updateHeaderUsername();
      setFeedback("Account wurde gelöscht.", "success");
      return;
    }

    if (result.status === 401) {
      setFeedback("Account konnte nicht gelöscht werden: nicht autorisiert.", "danger");
      return;
    }

    setFeedback(
      "Account konnte nicht gelöscht werden (Status " + result.status + ").",
      "danger",
    );
  }

  function initLoginPage() {
    const loginForm = document.getElementById("login-form");
    const registerForm = document.getElementById("register-form");
    const logoutButton = document.getElementById("logout-button");
    const deleteAccountButton = document.getElementById("delete-account-button");

    if (!loginForm || !registerForm || !logoutButton || !deleteAccountButton) {
      return;
    }

    loginForm.addEventListener("submit", handleLoginSubmit);
    registerForm.addEventListener("submit", handleRegisterSubmit);
    logoutButton.addEventListener("click", handleLogout);
    deleteAccountButton.addEventListener("click", handleDeleteAccount);

    updateSessionBox();
    updateHeaderUsername();
  }

  window.initLoginPage = initLoginPage;
  window.AppAuth = {
    getAuth: readAuth,
    clearAuth: clearAuth,
  };

  document.addEventListener("DOMContentLoaded", updateHeaderUsername);
})();