import './StaticParty.css';
import html from './StaticParty.html';
import {
  deleteStaticParty,
  getStaticParty,
  joinStaticParty,
  leaveStaticParty,
  markStaticItemWatched,
  startCatchUp,
  startStaticSession
} from '../../api/staticParty';
import { navigate } from '../../router';
import type { RouteParams } from '../../router';
import { escapeHtml } from '../../tiles';
import { LOADING_HINT } from '../../loading';
import { showToast } from '../../toast';
import type { StaticPartyDetailDto, StaticPartyItemDto } from '../../types';

/**
 * Route `/static/:id` - one static (persistent) watch party: the group's
 * progress through the whole series/playlist, its members, and - the
 * point of the feature - what *you* missed, with ways to catch up (alone,
 * or as a watch party others can join) or mark things as already seen.
 * Launching the group's session hands off to the normal player
 * (`/party/:id`) - a session is an ordinary party server-side. See
 * server/src/services/StaticPartyService.ts and spec/static-watch-party.md.
 */
export async function renderStaticParty(root: HTMLElement, params: RouteParams): Promise<void> {
  const staticId = params.id as string;
  root.innerHTML = LOADING_HINT;

  let detail: StaticPartyDetailDto;
  try {
    detail = await getStaticParty(staticId);
  } catch (err) {
    console.error('[staticParty] load failed', staticId, err);
    root.innerHTML = `<p class="error">${escapeHtml((err as Error).message || 'Impossible de charger cette watch party.')}</p>`;
    return;
  }

  root.innerHTML = html;
  root.querySelector('#back')!.addEventListener('click', () => history.back());
  wireActions(root, staticId);
  render(root, detail);
}

/** Re-fetches and re-renders in place - after any action that changed
 *  progress or membership. */
async function reload(root: HTMLElement, staticId: string): Promise<void> {
  try {
    const detail = await getStaticParty(staticId);
    if (!root.querySelector('#staticTitle')) return; // navigated away mid-flight
    render(root, detail);
  } catch (err) {
    console.error('[staticParty] reload failed', staticId, err);
    showToast((err as Error).message, { variant: 'error' });
  }
}

/** Fills every part of the page from `detail`. */
function render(root: HTMLElement, detail: StaticPartyDetailDto): void {
  (root.querySelector('#staticCover') as HTMLImageElement).src = detail.imageUrl;
  root.querySelector('#staticTitle')!.textContent = detail.name;
  const sourceLabel = detail.sourceType === 'series' ? 'Série' : 'Playlist';
  root.querySelector('#staticMeta')!.textContent =
    `${sourceLabel} · ${detail.groupWatchedCount}/${detail.itemCount} vus par le groupe · ${detail.memberCount} membre${detail.memberCount > 1 ? 's' : ''}`;
  const percent = detail.itemCount ? Math.round((detail.groupWatchedCount / detail.itemCount) * 100) : 0;
  (root.querySelector('#staticProgressFill') as HTMLElement).style.width = `${percent}%`;
  root.querySelector('#staticNext')!.innerHTML = detail.nextItemName
    ? `Prochain : <strong>${escapeHtml(detail.nextItemName)}</strong>`
    : '<strong>Le groupe a tout vu.</strong>';

  const sessionBtn = root.querySelector('#sessionBtn') as HTMLButtonElement;
  sessionBtn.textContent = detail.livePartyId ? 'Rejoindre la séance en cours' : 'Lancer la séance';
  sessionBtn.disabled = !detail.livePartyId && !detail.nextItemName;
  root.querySelector('#joinBtn')!.classList.toggle('hide', detail.youAreMember);
  root.querySelector('#leaveBtn')!.classList.toggle('hide', !detail.youAreMember || detail.youAreCreator);
  root.querySelector('#deleteBtn')!.classList.toggle('hide', !detail.youAreCreator);

  renderMissed(root, detail);
  renderMembers(root, detail);
  renderItems(root, detail);
}

/** "Tu as manqué" - hidden entirely when there's nothing to catch up on. */
function renderMissed(root: HTMLElement, detail: StaticPartyDetailDto): void {
  const section = root.querySelector('#missedSection') as HTMLElement;
  const missed = new Set(detail.missedItemIds);
  const items = detail.items.filter((i) => missed.has(i.itemId));
  section.hidden = !items.length;
  root.querySelector('#missedCount')!.textContent = String(items.length);
  root.querySelector('#missedList')!.innerHTML = items.map((item) => `
    <div class="episodeRow">
      <input type="checkbox" class="staticCheck" data-item-id="${escapeHtml(item.itemId)}" checked aria-label="Inclure dans le rattrapage" />
      <img src="${escapeHtml(item.itemImageUrl)}" alt="" loading="lazy" onerror="this.classList.add('noImage')" />
      <div class="episodeInfo"><strong>${escapeHtml(item.itemName)}</strong></div>
      <div class="staticRowActions">
        <button class="secondaryBtn soloOneBtn" data-item-id="${escapeHtml(item.itemId)}">Regarder en solo</button>
        <button class="secondaryBtn markWatchedBtn" data-item-id="${escapeHtml(item.itemId)}">Marquer comme vu</button>
      </div>
    </div>`).join('');
}

/** One chip per member, with how many items they've watched. */
function renderMembers(root: HTMLElement, detail: StaticPartyDetailDto): void {
  root.querySelector('#memberList')!.innerHTML = detail.members.length
    ? detail.members.map((m) => `
      <span class="staticMember">${escapeHtml(m.userName)}${m.isCreator ? ' ★' : ''}<span class="hint">${m.watchedCount}/${detail.itemCount}</span></span>`).join('')
    : '<p class="hint">Aucun membre pour le moment.</p>';
}

/** The whole item list, with the group's state and the viewer's own. */
function renderItems(root: HTMLElement, detail: StaticPartyDetailDto): void {
  root.querySelector('#itemList')!.innerHTML = detail.items.map((item, i) => `
    <div class="episodeRow${item.groupState === 'watched' ? ' isWatched' : ''}${item.groupState === 'next' ? ' isNext' : ''}">
      <img src="${escapeHtml(item.itemImageUrl)}" alt="" loading="lazy" onerror="this.classList.add('noImage')" />
      <div class="episodeInfo"><strong>${i + 1}. ${escapeHtml(item.itemName)}</strong></div>
      <span class="staticState">${stateLabel(item)}${item.viewerWatched ? '<span class="mine">✓ vu par toi</span>' : ''}</span>
    </div>`).join('');
}

/** The group-state label for one item. */
function stateLabel(item: StaticPartyItemDto): string {
  if (item.groupState === 'watched') return 'Vu par le groupe';
  if (item.groupState === 'next') return 'Prochain';
  return 'À venir';
}

/**
 * Wires every button once - lists are re-rendered on reload, so row
 * buttons use one delegated listener on their container rather than
 * per-row listeners re-added on every render.
 */
function wireActions(root: HTMLElement, staticId: string): void {
  const sessionBtn = root.querySelector('#sessionBtn') as HTMLButtonElement;
  sessionBtn.addEventListener('click', () => {
    runBusy(sessionBtn, async () => {
      const { partyId } = await startStaticSession(staticId);
      navigate(`/party/${partyId}`);
    });
  });

  const joinBtn = root.querySelector('#joinBtn') as HTMLButtonElement;
  joinBtn.addEventListener('click', () => {
    runBusy(joinBtn, async () => {
      await joinStaticParty(staticId);
      showToast('Tu fais maintenant partie de cette watch party.');
      await reload(root, staticId);
    });
  });

  const leaveBtn = root.querySelector('#leaveBtn') as HTMLButtonElement;
  leaveBtn.addEventListener('click', () => {
    if (!confirm('Quitter cette watch party ? Ta progression y sera oubliée.')) return;
    runBusy(leaveBtn, async () => {
      await leaveStaticParty(staticId);
      await reload(root, staticId);
    });
  });

  const deleteBtn = root.querySelector('#deleteBtn') as HTMLButtonElement;
  deleteBtn.addEventListener('click', () => {
    if (!confirm('Supprimer cette watch party pour tout le monde ? La progression de chacun sera perdue.')) return;
    runBusy(deleteBtn, async () => {
      await deleteStaticParty(staticId);
      showToast('Watch party supprimée.');
      navigate('/home');
    });
  });

  const catchUp = (btn: HTMLButtonElement, mode: 'solo' | 'party') => {
    const itemIds = Array.from(root.querySelectorAll<HTMLInputElement>('#missedList .staticCheck'))
      .filter((c) => c.checked)
      .map((c) => c.dataset.itemId as string);
    if (!itemIds.length) {
      showToast('Coche au moins un élément à rattraper.', { variant: 'error' });
      return;
    }
    runBusy(btn, async () => {
      const { partyId } = await startCatchUp(staticId, itemIds, mode);
      navigate(`/party/${partyId}`);
    });
  };
  const soloBtn = root.querySelector('#catchUpSoloBtn') as HTMLButtonElement;
  const partyBtn = root.querySelector('#catchUpPartyBtn') as HTMLButtonElement;
  soloBtn.addEventListener('click', () => catchUp(soloBtn, 'solo'));
  partyBtn.addEventListener('click', () => catchUp(partyBtn, 'party'));

  root.querySelector('#missedList')!.addEventListener('click', (e) => {
    const btn = (e.target as HTMLElement).closest<HTMLButtonElement>('button[data-item-id]');
    if (!btn) return;
    const itemId = btn.dataset.itemId as string;
    if (btn.classList.contains('soloOneBtn')) {
      runBusy(btn, async () => {
        const { partyId } = await startCatchUp(staticId, [itemId], 'solo');
        navigate(`/party/${partyId}`);
      });
    } else if (btn.classList.contains('markWatchedBtn')) {
      runBusy(btn, async () => {
        await markStaticItemWatched(staticId, itemId);
        await reload(root, staticId);
      });
    }
  });
}

/** Disables `btn` while `action` runs; a failure is toasted, logged, and
 *  gives the button back. */
function runBusy(btn: HTMLButtonElement, action: () => Promise<void>): void {
  btn.disabled = true;
  action()
    .catch((err: unknown) => {
      console.error('[staticParty] action failed', err);
      showToast((err as Error).message, { variant: 'error' });
    })
    .finally(() => {
      btn.disabled = false;
    });
}