(function (ns) {
  'use strict';

  const dialog = document.getElementById('info-dialog');
  const title = document.getElementById('info-dialog-title');
  const menu = document.getElementById('info-menu');
  const backButton = document.getElementById('info-back');
  const closeButton = document.getElementById('info-close');
  const infoButton = document.getElementById('info-button');
  const pageTitles = Object.freeze({
    privacy: 'Datenschutzerklärung',
    imprint: 'Impressum',
    technology: 'Cookies und Technik'
  });

  function ready(callback) {
    if (document.readyState === 'loading') {
      document.addEventListener('DOMContentLoaded', callback, { once: true });
      return;
    }
    callback();
  }

  function createElement(tagName, attributes = {}, text = '') {
    const element = document.createElement(tagName);
    Object.entries(attributes).forEach(([name, value]) => {
      if (value === null || value === undefined) return;
      if (name === 'className') {
        element.className = value;
        return;
      }
      if (name === 'dataset') {
        Object.entries(value).forEach(([key, dataValue]) => {
          element.dataset[key] = dataValue;
        });
        return;
      }
      element.setAttribute(name, value);
    });
    if (text) element.textContent = text;
    return element;
  }

  function ensureInfoControl() {
    let control = document.querySelector('.info-control');
    let button = document.getElementById('info-button')
      ?? document.querySelector('[aria-controls="info-dropdown"], .info-button');
    let dropdown = document.getElementById('info-dropdown')
      ?? document.querySelector('.info-dropdown');

    if (!control) {
      control = createElement('div', { className: 'info-control' });
      document.body.insertBefore(control, document.body.firstChild);
    }

    if (!button) {
      button = createElement('button', {
        id: 'info-button',
        className: 'info-button',
        type: 'button',
        'aria-label': 'Informationsmenü öffnen',
        title: 'Informationen'
      });
      const icon = createElement('span', { 'aria-hidden': 'true' }, 'i');
      button.appendChild(icon);
    }

    if (button.parentElement !== control) {
      control.insertBefore(button, control.firstChild);
    }

    button.id = 'info-button';
    button.classList.add('info-button');
    button.setAttribute('type', 'button');
    button.setAttribute('aria-haspopup', 'true');
    button.setAttribute('aria-expanded', 'false');
    button.setAttribute('aria-controls', 'info-dropdown');
    if (!button.getAttribute('aria-label')) button.setAttribute('aria-label', 'Informationsmenü öffnen');
    if (!button.textContent.trim()) {
      const icon = createElement('span', { 'aria-hidden': 'true' }, 'i');
      button.appendChild(icon);
    }

    if (!dropdown) {
      dropdown = createElement('nav', {
        id: 'info-dropdown',
        className: 'info-dropdown',
        'aria-label': 'Rechtliche und technische Informationen'
      });
    }

    if (dropdown.parentElement !== control) {
      control.appendChild(dropdown);
    }

    dropdown.id = 'info-dropdown';
    dropdown.classList.add('info-dropdown');
    dropdown.setAttribute('aria-label', dropdown.getAttribute('aria-label') ?? 'Rechtliche und technische Informationen');
    dropdown.hidden = true;

    menuEntries.forEach(([target, label]) => {
      let menuButton = dropdown.querySelector(`[data-info-target="${target}"]`);
      if (!menuButton) {
        menuButton = createElement('button', {
          type: 'button',
          dataset: { infoTarget: target }
        }, label);
        dropdown.appendChild(menuButton);
      }
      menuButton.setAttribute('type', 'button');
      menuButton.dataset.infoTarget = target;
      if (!menuButton.textContent.trim()) menuButton.textContent = label;
    });

    return { control, button, dropdown };
  }

  function moveExistingPagesInto(content, dialog) {
    dialog.querySelectorAll('[data-info-page]').forEach(page => {
      if (page.parentElement !== content) content.appendChild(page);
    });
  }

  function ensureInfoPage(content, name) {
    let page = content.querySelector(`[data-info-page="${name}"]`)
      ?? document.querySelector(`[data-info-page="${name}"]`);

    if (!page) {
      page = createElement('article', {
        className: 'info-page',
        dataset: { infoPage: name }
      });
      page.appendChild(createElement('p', {}, `${pageTitles[name]} ist noch nicht hinterlegt.`));
      content.appendChild(page);
    }

    page.classList.add('info-page');
    page.dataset.infoPage = name;
    page.hidden = true;
    if (page.parentElement !== content) content.appendChild(page);
    return page;
  }

  function ensureInfoDialog() {
    let dialog = document.getElementById('info-dialog');
    if (!dialog) {
      dialog = createElement('dialog', {
        id: 'info-dialog',
        className: 'info-dialog',
        'aria-labelledby': 'info-dialog-title'
      });
      document.body.appendChild(dialog);
    }

    dialog.id = 'info-dialog';
    dialog.classList.add('info-dialog');
    dialog.setAttribute('aria-labelledby', 'info-dialog-title');

    let shell = dialog.querySelector('.info-dialog-shell');
    if (!shell) {
      shell = createElement('div', { className: 'info-dialog-shell' });
      while (dialog.firstChild) shell.appendChild(dialog.firstChild);
      dialog.appendChild(shell);
    }

    let header = shell.querySelector('.info-dialog-header');
    if (!header) {
      header = createElement('header', { className: 'info-dialog-header' });
      shell.insertBefore(header, shell.firstChild);
    }

    let title = document.getElementById('info-dialog-title')
      ?? header.querySelector('h1, h2, .info-dialog-title');
    if (!title) {
      title = createElement('h2', { id: 'info-dialog-title' }, 'Informationen');
      header.insertBefore(title, header.firstChild);
    }
    title.id = 'info-dialog-title';
    if (!title.textContent.trim()) title.textContent = 'Informationen';

    let closeButton = document.getElementById('info-close')
      ?? header.querySelector('[data-info-close], .info-close, .info-dialog-close, button[aria-label="Dialog schließen"], button[aria-label="Schließen"]');
    if (!closeButton) {
      closeButton = createElement('button', {
        id: 'info-close',
        type: 'button',
        'aria-label': 'Informationsfenster schließen',
        title: 'Schließen'
      }, '×');
      header.appendChild(closeButton);
    }
    closeButton.id = 'info-close';
    closeButton.setAttribute('type', 'button');
    closeButton.setAttribute('aria-label', closeButton.getAttribute('aria-label') ?? 'Informationsfenster schließen');
    closeButton.setAttribute('title', closeButton.getAttribute('title') ?? 'Schließen');
    if (!closeButton.textContent.trim()) closeButton.textContent = '×';
    if (closeButton.parentElement !== header) header.appendChild(closeButton);

    let content = shell.querySelector('.info-dialog-content');
    if (!content) {
      content = createElement('div', { className: 'info-dialog-content' });
      shell.appendChild(content);
    }

    moveExistingPagesInto(content, dialog);
    Object.keys(pageTitles).forEach(name => ensureInfoPage(content, name));

    return { dialog, title, closeButton, content };
  }

  function ensureInfoUi() {
    const control = ensureInfoControl();
    const dialog = ensureInfoDialog();
    return {
      control: control.control,
      infoButton: control.button,
      dropdown: control.dropdown,
      dialog: dialog.dialog,
      title: dialog.title,
      closeButton: dialog.closeButton,
      content: dialog.content
    };
  }

  function isActivation(event) {
    if (event.type === 'keydown') return event.key === 'Enter' || event.key === ' ';
    if (event.type !== 'pointerup') return false;
    if (event.isPrimary === false) return false;
    return event.pointerType !== 'mouse' || event.button === 0;
  }

  function activate(element, handler) {
    element.addEventListener('pointerup', event => {
      if (!isActivation(event)) return;
      event.preventDefault();
      event.stopPropagation();
      handler(event);
    });
    element.addEventListener('keydown', event => {
      if (!isActivation(event)) return;
      event.preventDefault();
      event.stopPropagation();
      handler(event);
    });
  }

  function syncStorageToggles() {
    const enabled = isProgressStorageEnabled();
    document.querySelectorAll('.progress-storage-toggle').forEach(toggle => {
      toggle.checked = enabled;
    });
    document.querySelectorAll('.cookie-toggle').forEach(toggle => {
      toggle.checked = false;
    });
  }

  function showMenu() {
    title.textContent = 'Informationen';
    menu.hidden = false;
    backButton.hidden = true;
    document.querySelectorAll('[data-info-page]').forEach(page => {
      page.hidden = true;
    });
  }

  function showPage(name) {
    const pageName = Object.prototype.hasOwnProperty.call(pageTitles, name) ? name : 'privacy';
    const page = elements?.content?.querySelector(`[data-info-page="${pageName}"]`)
      ?? document.querySelector(`[data-info-page="${pageName}"]`);
    if (!page) return;

    title.textContent = pageTitles[name] ?? 'Informationen';
    menu.hidden = true;
    backButton.hidden = false;
    document.querySelectorAll('[data-info-page]').forEach(item => {
      item.hidden = item !== page;
    });
    if (elements?.content) elements.content.scrollTop = 0;
  }

  function focusSafely(element) {
    if (!element || typeof element.focus !== 'function') return;
    try {
      element.focus({ preventScroll: true });
    } catch {
      element.focus();
    }
  }

  function openDialog() {
    if (dialog.open) return;
    showMenu();
    syncStorageToggles();
    if (typeof dialog.showModal === 'function') dialog.showModal();
    else dialog.setAttribute('open', '');
    closeButton.focus();
  }

  function closeDialog() {
    if (typeof dialog.close === 'function') dialog.close();
    else dialog.removeAttribute('open');
    infoButton.focus();
  }

  function bindStorageToggles() {
    document.querySelectorAll('.progress-storage-toggle').forEach(toggle => {
      if (toggle.dataset.wegwichtelStorageBound === 'true') return;
      toggle.dataset.wegwichtelStorageBound = 'true';
      toggle.addEventListener('change', event => {
        const enabled = setProgressStorageEnabled(event.currentTarget.checked);
        syncStorageToggles();
        document.dispatchEvent(new CustomEvent('wegwichtel:progress-storage-changed', {
          detail: { enabled }
        }));
      });
    });
  }

  activate(infoButton, openDialog);
  activate(closeButton, closeDialog);
  activate(backButton, showMenu);
  document.querySelectorAll('[data-info-target]').forEach(button => {
    activate(button, () => showPage(button.dataset.infoTarget));
  });

    if (elements.dialog.dataset.wegwichtelLegalUiDialogBound !== 'true') {
      elements.dialog.dataset.wegwichtelLegalUiDialogBound = 'true';
      elements.dialog.addEventListener('pointerup', event => {
        if (event.target !== elements.dialog || !isActivation(event)) return;
        event.preventDefault();
        event.stopPropagation();
        closeDialog();
      });
      elements.dialog.addEventListener('cancel', event => {
        event.preventDefault();
        closeDialog();
      });
    }
  }

  function init() {
    elements = ensureInfoUi();
    bindDialog();
    bindStorageToggles();
    syncStorageToggles();

    ns.LegalUi = Object.freeze({
      open: openDialog,
      close: closeDialog,
      toggleMenu: toggleDropdown,
      closeMenu: () => setDropdownOpen(false),
      syncStorageToggles
    });
  }

  ns.LegalUi = Object.freeze({ open: openDialog, close: closeDialog, syncStorageToggles });
}(globalThis.Wegwichtel ??= {}));