(function () {
  const EMAIL_STORAGE_KEY = 'ff_member_form_email_v1';
  const DISCLAIMER_ACCEPTED_KEY = 'ff_member_form_disclaimer_accepted_v1';
  const boot = window.APP_BOOT || { steps: [], csrf: '', contactEmail: '' };
  const baseUrl = String(boot.baseUrl || '').replace(/\/+$/, '');

  const state = {
    email: '',
    currentStep: 1,
    totalSteps: boot.steps.length,
    autosaveId: null,
  };

  const disclaimerSection = document.getElementById('disclaimerSection');
  const acceptDisclaimerBtn = document.getElementById('acceptDisclaimerBtn');
  const startSection = document.getElementById('startSection');
  const startForm = document.getElementById('startForm');
  const startIntroText = document.getElementById('startIntroText');
  const startEmailField = document.getElementById('startEmailField');
  const startActions = document.getElementById('startActions');
  const startEmailInput = document.getElementById('startEmail');
  const resetDataBtn = document.getElementById('resetDataBtn');
  const compactStatusBox = document.getElementById('compactStatusBox');
  const statusEmailValue = document.getElementById('statusEmailValue');
  const draftStatusValue = document.getElementById('draftStatusValue');
  const feedbackMessage = document.getElementById('feedbackMessage');

  const wizardSection = document.getElementById('wizardSection');
  const applicationForm = document.getElementById('applicationForm');
  const applicationEmail = document.getElementById('applicationEmail');
  const progress = document.getElementById('progress');
  const prevBtn = document.getElementById('prevBtn');
  const nextBtn = document.getElementById('nextBtn');
  const submitBtn = document.getElementById('submitBtn');
  const stepElements = Array.from(document.querySelectorAll('.step'));

  function appUrl(path) {
    const normalizedPath = String(path || '').replace(/^\/+/, '');
    return (baseUrl ? baseUrl + '/' : '/') + normalizedPath;
  }

  function setFeedback(text, isError) {
    feedbackMessage.textContent = text || '';
    feedbackMessage.classList.toggle('error-text', Boolean(isError));
  }

  function setDraftStatus(text, isError) {
    draftStatusValue.textContent = text || '';
    draftStatusValue.classList.toggle('error-text', Boolean(isError));
  }

  function formatTimestamp(isoDate) {
    if (!isoDate) {
      return '';
    }

    const date = new Date(isoDate);
    if (Number.isNaN(date.getTime())) {
      return String(isoDate);
    }

    return date.toLocaleString('de-DE');
  }

  function normalizeEmail(email) {
    return (email || '').trim().toLowerCase();
  }

  function isValidEmail(email) {
    return /^[^\s@]+@[^\s@]+\.[^\s@]+$/.test(email);
  }

  function rememberEmail(email) {
    try {
      localStorage.setItem(EMAIL_STORAGE_KEY, email);
    } catch (_err) {
      // ignore localStorage errors
    }
  }

  function getRememberedEmail() {
    try {
      return localStorage.getItem(EMAIL_STORAGE_KEY) || '';
    } catch (_err) {
      return '';
    }
  }

  function forgetRememberedEmail() {
    try {
      localStorage.removeItem(EMAIL_STORAGE_KEY);
    } catch (_err) {
      // ignore localStorage errors
    }
  }

  function hasAcceptedDisclaimer() {
    try {
      return localStorage.getItem(DISCLAIMER_ACCEPTED_KEY) === '1';
    } catch (_err) {
      return false;
    }
  }

  function setDisclaimerAccepted() {
    try {
      localStorage.setItem(DISCLAIMER_ACCEPTED_KEY, '1');
    } catch (_err) {
      // ignore localStorage errors
    }
  }

  function enterCompactStatus(email) {
    statusEmailValue.textContent = email;
    startSection.classList.add('compact-mode');
    compactStatusBox.classList.remove('hidden');
    startIntroText.classList.add('hidden');
    startEmailField.classList.add('hidden');
    startActions.classList.add('hidden');
  }

  function leaveCompactStatus() {
    startSection.classList.remove('compact-mode');
    compactStatusBox.classList.add('hidden');
    startIntroText.classList.remove('hidden');
    startEmailField.classList.remove('hidden');
    startActions.classList.remove('hidden');
    statusEmailValue.textContent = '-';
    setDraftStatus('Noch nicht gespeichert', false);
  }

  function lockEmail(email) {
    state.email = email;
    applicationEmail.value = email;
    startEmailInput.value = email;
    startEmailInput.readOnly = true;
    startEmailInput.setAttribute('aria-readonly', 'true');
    rememberEmail(email);
    enterCompactStatus(email);
  }

  function unlockEmail(clearInput) {
    state.email = '';
    applicationEmail.value = '';
    startEmailInput.readOnly = false;
    startEmailInput.removeAttribute('aria-readonly');
    if (clearInput) {
      startEmailInput.value = '';
    }
    forgetRememberedEmail();
    leaveCompactStatus();
  }

  function stopAutosave() {
    if (state.autosaveId) {
      clearInterval(state.autosaveId);
      state.autosaveId = null;
    }
  }

  function startAutosave() {
    stopAutosave();
    state.autosaveId = setInterval(async () => {
      if (!state.email || wizardSection.classList.contains('hidden')) {
        return;
      }
      try {
        await saveDraft(false);
      } catch (_err) {
        // visible on next manual action
      }
    }, 15000);
  }

  function clearErrors() {
    document.querySelectorAll('[data-error-for]').forEach((el) => {
      el.textContent = '';
    });
  }

  function showErrors(errors) {
    clearErrors();
    Object.keys(errors || {}).forEach((key) => {
      const el = document.querySelector('[data-error-for="' + key + '"]');
      if (el) {
        el.textContent = errors[key];
      }
    });
  }

  function clearWizardData() {
    applicationForm.reset();
    clearErrors();
    renderUploadInfo({});
    state.currentStep = 1;
    submitBtn.disabled = false;
    nextBtn.disabled = false;
    prevBtn.disabled = false;
    updateProgress();
    Array.from(document.querySelectorAll('[data-upload-key]')).forEach((control) => {
      const fieldKey = control.getAttribute('data-upload-key');
      if (fieldKey) {
        updateUploadSelectionText(fieldKey);
      }
    });
  }

  function updateProgress() {
    progress.textContent = 'Schritt ' + state.currentStep + ' von ' + state.totalSteps;
    stepElements.forEach((el) => {
      const step = Number(el.getAttribute('data-step'));
      el.classList.toggle('hidden', step !== state.currentStep);
    });

    prevBtn.disabled = state.currentStep === 1;
    nextBtn.classList.toggle('hidden', state.currentStep === state.totalSteps);
    submitBtn.classList.toggle('hidden', state.currentStep !== state.totalSteps);
  }

  function fillFormData(data) {
    Object.keys(data || {}).forEach((key) => {
      const field = applicationForm.querySelector('[name="form_data[' + key + ']"]');
      if (!field) return;

      if (field.type === 'checkbox') {
        field.checked = ['1', 'on', 'true', true].includes(data[key]);
      } else {
        field.value = data[key] || '';
      }
    });
  }

  function renderUploadInfo(uploads) {
    document.querySelectorAll('[data-upload-list]').forEach((el) => {
      el.innerHTML = '';
    });

    Object.keys(uploads || {}).forEach((field) => {
      const target = document.querySelector('[data-upload-list="' + field + '"]');
      if (!target || !Array.isArray(uploads[field])) return;

      uploads[field].forEach((item) => {
        const div = document.createElement('div');
        div.className = 'upload-item';
        div.textContent = item.original_filename + ' (' + item.uploaded_at + ')';
        target.appendChild(div);
      });
    });
  }

  function updateUploadSelectionText(fieldKey) {
    const target = document.querySelector('[data-upload-selected="' + fieldKey + '"]');
    if (!target) {
      return;
    }

    const fileInput = applicationForm.querySelector('[name="' + fieldKey + '"]');
    const cameraInput = applicationForm.querySelector('[name="' + fieldKey + '__camera"]');

    let label = 'Keine Datei gewählt';
    if (fileInput && fileInput.files && fileInput.files[0]) {
      label = 'Ausgewählt: ' + fileInput.files[0].name;
    }
    if (cameraInput && cameraInput.files && cameraInput.files[0]) {
      label = 'Ausgewählt: ' + cameraInput.files[0].name + ' (Foto)';
    }

    target.textContent = label;
  }

  async function triggerInstantUpload() {
    if (!state.email || wizardSection.classList.contains('hidden')) {
      return;
    }

    setDraftStatus('Datei wird hochgeladen ...', false);
    try {
      await saveDraft(true);
      setFeedback('', false);
    } catch (err) {
      const msg = (err.payload && err.payload.message) || err.message || 'Upload fehlgeschlagen.';
      setDraftStatus('Upload fehlgeschlagen', true);
      setFeedback(msg, true);
    }
  }

  function initUploadControls() {
    const controls = Array.from(document.querySelectorAll('[data-upload-key]'));

    controls.forEach((control) => {
      const fieldKey = control.getAttribute('data-upload-key') || '';
      if (!fieldKey) {
        return;
      }

      const fileInput = applicationForm.querySelector('[name="' + fieldKey + '"]');
      const cameraInput = applicationForm.querySelector('[name="' + fieldKey + '__camera"]');

      if (fileInput) {
        fileInput.addEventListener('change', async () => {
          if (fileInput.files && fileInput.files[0] && cameraInput) {
            cameraInput.value = '';
          }
          updateUploadSelectionText(fieldKey);
          if (fileInput.files && fileInput.files[0]) {
            await triggerInstantUpload();
          }
        });
      }

      if (cameraInput) {
        cameraInput.addEventListener('change', async () => {
          if (cameraInput.files && cameraInput.files[0] && fileInput) {
            fileInput.value = '';
          }
          updateUploadSelectionText(fieldKey);
          if (cameraInput.files && cameraInput.files[0]) {
            await triggerInstantUpload();
          }
        });
      }

      updateUploadSelectionText(fieldKey);
    });
  }

  async function postForm(url, formData) {
    const response = await fetch(url, {
      method: 'POST',
      body: formData,
      credentials: 'same-origin',
      headers: { 'X-Requested-With': 'XMLHttpRequest' },
    });

    const payload = await response.json();
    if (!response.ok || payload.ok === false) {
      const err = new Error(payload.message || 'Anfrage fehlgeschlagen');
      err.payload = payload;
      throw err;
    }

    return payload;
  }

  function collectPayload(includeFiles) {
    const fd = new FormData();
    fd.append('csrf', boot.csrf);
    fd.append('email', state.email);
    fd.append('step', String(state.currentStep));
    fd.append('website', '');

    Array.from(applicationForm.elements).forEach((el) => {
      if (!el.name) return;
      if (!el.name.startsWith('form_data[')) return;

      if (el.type === 'checkbox') {
        fd.append(el.name, el.checked ? '1' : '0');
      } else {
        fd.append(el.name, el.value || '');
      }
    });

    if (includeFiles) {
      Array.from(applicationForm.querySelectorAll('input[type="file"]')).forEach((input) => {
        if (input.files && input.files[0]) {
          fd.append(input.name, input.files[0]);
        }
      });
    }

    return fd;
  }

  async function loadDraft(email) {
    const fd = new FormData();
    fd.append('csrf', boot.csrf);
    fd.append('email', email);
    fd.append('website', '');
    return postForm(appUrl('api/load-draft.php'), fd);
  }

  async function resetSavedData(email) {
    const fd = new FormData();
    fd.append('csrf', boot.csrf);
    fd.append('email', email);
    fd.append('website', '');
    return postForm(appUrl('api/reset.php'), fd);
  }

  async function saveDraft(includeFiles) {
    const payload = collectPayload(includeFiles);
    const response = await postForm(appUrl('api/save-draft.php'), payload);

    if (response.upload_errors && Object.keys(response.upload_errors).length > 0) {
      showErrors(response.upload_errors);
      setDraftStatus('Uploadfehler', true);
      setFeedback('Einige Dateien konnten nicht gespeichert werden.', true);
    } else {
      const ts = formatTimestamp(response.updated_at);
      setDraftStatus('Gespeichert: ' + (ts || 'gerade eben'), false);
    }

    if (response.uploads) {
      renderUploadInfo(response.uploads);
    }

    if (includeFiles) {
      Array.from(applicationForm.querySelectorAll('input[type="file"]')).forEach((input) => {
        input.value = '';
      });
      Array.from(document.querySelectorAll('[data-upload-key]')).forEach((control) => {
        const fieldKey = control.getAttribute('data-upload-key');
        if (fieldKey) {
          updateUploadSelectionText(fieldKey);
        }
      });
    }

    return response;
  }

  async function submitApplication() {
    const payload = collectPayload(true);
    const response = await postForm(appUrl('api/submit.php'), payload);
    clearErrors();
    setDraftStatus('Abgeschlossen', false);
    setFeedback('Antrag erfolgreich abgeschlossen. Vielen Dank.', false);
    submitBtn.disabled = true;
    nextBtn.disabled = true;
    prevBtn.disabled = true;
    return response;
  }

  async function startProcess(rawEmail) {
    const email = normalizeEmail(rawEmail);
    if (!isValidEmail(email)) {
      setFeedback('Bitte eine gültige E-Mail-Adresse eingeben.', true);
      startEmailInput.focus();
      return;
    }

    try {
      const result = await loadDraft(email);
      lockEmail(email);

      if (result.already_submitted) {
        wizardSection.classList.add('hidden');
        setDraftStatus('Antrag bereits abgeschlossen', false);
        setFeedback(boot.contactEmail ? 'Kontakt: ' + boot.contactEmail : '', false);
        stopAutosave();
        return;
      }

      wizardSection.classList.remove('hidden');
      fillFormData(result.data || {});
      renderUploadInfo(result.uploads || {});

      state.currentStep = Math.min(Math.max(Number(result.step || 1), 1), state.totalSteps);
      updateProgress();
      startAutosave();

      const loadedAt = formatTimestamp(result.updated_at);
      if (loadedAt) {
        setDraftStatus('Entwurf geladen: ' + loadedAt, false);
      } else {
        setDraftStatus('Neuer Entwurf gestartet', false);
      }
      setFeedback('', false);
    } catch (err) {
      const msg = (err.payload && err.payload.message) || err.message || 'Laden fehlgeschlagen.';
      setFeedback(msg, true);
    }
  }

  startForm.addEventListener('submit', async (event) => {
    event.preventDefault();
    await startProcess(startEmailInput.value || '');
  });

  resetDataBtn.addEventListener('click', async () => {
    if (!state.email) {
      setFeedback('Keine aktive E-Mail vorhanden.', true);
      return;
    }

    const confirmed = window.confirm('Alle gespeicherten Daten zu dieser E-Mail endgültig löschen und neu starten?');
    if (!confirmed) {
      return;
    }

    try {
      await resetSavedData(state.email);
      stopAutosave();
      wizardSection.classList.add('hidden');
      clearWizardData();
      unlockEmail(true);
      setFeedback('Alle gespeicherten Daten wurden gelöscht. Sie können neu starten.', false);
      startEmailInput.focus();
    } catch (err) {
      const msg = (err.payload && err.payload.message) || err.message || 'Löschen fehlgeschlagen.';
      setFeedback(msg, true);
    }
  });

  prevBtn.addEventListener('click', async () => {
    if (state.currentStep <= 1) return;

    try {
      await saveDraft(false);
      state.currentStep -= 1;
      updateProgress();
    } catch (err) {
      const msg = (err.payload && err.payload.message) || err.message;
      setFeedback(msg, true);
    }
  });

  nextBtn.addEventListener('click', async () => {
    if (state.currentStep >= state.totalSteps) return;

    try {
      await saveDraft(false);
      state.currentStep += 1;
      updateProgress();
    } catch (err) {
      const msg = (err.payload && err.payload.message) || err.message;
      setFeedback(msg, true);
    }
  });

  submitBtn.addEventListener('click', async () => {
    try {
      await submitApplication();
    } catch (err) {
      const payload = err.payload || {};
      if (payload.errors) {
        showErrors(payload.errors);
      }
      const msg = payload.message || err.message || 'Absenden fehlgeschlagen.';
      setFeedback(msg, true);
      if (payload.already_submitted) {
        wizardSection.classList.add('hidden');
        setDraftStatus('Antrag bereits abgeschlossen', false);
      }
    }
  });

  function initializeAfterDisclaimer() {
    disclaimerSection.classList.add('hidden');
    startSection.classList.remove('hidden');

    const rememberedEmail = normalizeEmail(getRememberedEmail());
    if (rememberedEmail !== '') {
      if (isValidEmail(rememberedEmail)) {
        startEmailInput.value = rememberedEmail;
        setFeedback('', false);
        startProcess(rememberedEmail);
      } else {
        forgetRememberedEmail();
      }
    }
  }

  if (acceptDisclaimerBtn) {
    acceptDisclaimerBtn.addEventListener('click', () => {
      setDisclaimerAccepted();
      initializeAfterDisclaimer();
    });
  }

  if (hasAcceptedDisclaimer()) {
    initializeAfterDisclaimer();
  } else {
    disclaimerSection.classList.remove('hidden');
    startSection.classList.add('hidden');
  }

  initUploadControls();
  updateProgress();
})();