import { ChatPanel } from './chat-app.js';
import { FilesPanel } from './files-app.js';
import { lazy } from './lazy.js';

// Chat and Files open with the group; every other app, and every settings
// pane, is fetched the first time it is shown (lazy.js) — a member who only
// chats never downloads the Videos app.
const VideoApp = lazy(() => import('./video-app.js'), 'VideoApp');
const MusicApp = lazy(() => import('./music-app.js'), 'MusicApp');
const PhotosApp = lazy(() => import('./photos-app.js'), 'PhotosApp');
const ChatSettings = lazy(() => import('./chat-app-settings.js'), 'ChatSettings');
const VideoSettings = lazy(() => import('./video-app-settings.js'), 'VideoSettings');
const MusicSettings = lazy(() => import('./music-app-settings.js'), 'MusicSettings');
const PhotoSettings = lazy(() => import('./photos-app-settings.js'), 'PhotoSettings');
const HelloWorldApp = lazy(() => import('./helloworld-app.js'), 'HelloWorldApp');
const HelloWorldSettings = lazy(() => import('./helloworld-app-settings.js'), 'HelloWorldSettings');

/**
 * Whether apps marked `dev` are shown. Opt in once with `?dev=1`, off with
 * `?dev=0` — persisted, the same shape as transport.js's `?trace=1`.
 *
 * HelloWorld exists to prove that adding an application is a registry entry
 * and two files. Registering it normally would put a toy app in every
 * operator's group; leaving it unregistered would prove nothing, since the
 * claim is precisely that registration is enough. So it is registered, and
 * hidden behind a flag that changes nothing else.
 */
const DEV_KEY = 'mb_dev_apps';
(function _initDevFlag() {
  try {
    const params = new URLSearchParams(location.search);
    if (params.has('dev')) {
      if (params.get('dev') === '0') localStorage.removeItem(DEV_KEY);
      else localStorage.setItem(DEV_KEY, '1');
    }
  } catch { /* localStorage unavailable — dev apps stay hidden */ }
})();

function devAppsShown() {
  try { return localStorage.getItem(DEV_KEY) === '1'; } catch { return false; }
}

/**
 * Every group "application", in tab order.
 *
 * Adding one means a new file exporting a component, an optional second file
 * exporting its settings pane, and one entry here. Nothing in `group-page.js`
 * or `group-settings.js` changes: every registered component receives the same
 * shared context (see `commonProps`) and renders itself into the active tab,
 * and every registered `Settings` gets its own collapsible section with a
 * toggle, rendered by a loop that names no app.
 *
 * `key` doubles as the identifier the node's `apps_enabled` setting and its
 * `app_directories` op use, so it must match `ALLOWED_APPS` in the node's
 * transport/webrtc/group_ops.py. It is also the key an app's directories are stored under
 * (`<key>_directories`) — one identifier per app, everywhere.
 *
 * Fields:
 *   key            the identifier, shared with the node
 *   icon, labelKey the tab
 *   Component      the app itself
 *   Settings       its operator settings pane, if it has any (optional)
 *   alwaysEnabled  cannot be turned off, and is not offered as a toggle
 */
const APPS = [
  { key: 'chat', icon: 'chat', labelKey: 'group.tab_chat',
    Component: ChatPanel, Settings: ChatSettings },
  // Files has no settings of its own: it works over every shared directory by
  // definition, which is what the shared-directories table already configures.
  { key: 'files', icon: 'folder', labelKey: 'group.tab_files',
    Component: FilesPanel, alwaysEnabled: true },
  { key: 'video', icon: 'video', labelKey: 'group.tab_video',
    Component: VideoApp, Settings: VideoSettings },
  { key: 'music', icon: 'music', labelKey: 'group.tab_music',
    Component: MusicApp, Settings: MusicSettings },
  { key: 'photo', icon: 'image', labelKey: 'group.tab_photos',
    Component: PhotosApp, Settings: PhotoSettings },
  // The reference implementation (docs/MESHBAY_DESIGN.md §9.4). `dev` keeps
  // it out of an operator's way; everything else about it is an ordinary
  // entry, which is the point.
  { key: 'helloworld', icon: 'chat', labelKey: 'group.tab_helloworld',
    Component: HelloWorldApp, Settings: HelloWorldSettings, dev: true },
];

/** Everything a reader of this page is allowed to see, in registry order. */
function availableApps() {
  const dev = devAppsShown();
  return APPS.filter(a => dev || !a.dev);
}

/** The registry filtered to what this group has enabled, in registry order. */
function visibleApps(enabledKeys) {
  const registered = availableApps();
  const enabled = new Set(
    enabledKeys && enabledKeys.length ? enabledKeys : registered.map(a => a.key));
  return registered.filter(a => a.alwaysEnabled || enabled.has(a.key));
}

/** The apps the Settings page offers a section for, in registry order. */
function configurableApps() {
  return availableApps().filter(a => !a.alwaysEnabled && a.Settings);
}

export { APPS, availableApps, visibleApps, configurableApps };