import { el, clear, onTeardown } from '../lib/dom.js';
import { loadSnapshot } from '../data/snapshot.js';
import { settings } from '../store/settings.js';
import { ui } from '../store/ui.js';
import { entry } from '../store/selection.js';
import { prettify } from '../data/pokedex-resolver.js';
import { getMoveIndex, getItemIndex, getMove, mapLimit } from '../data/api.js';
import { Sprite } from '../components/Sprite.js';
import { TypeChip } from '../components/TypeChip.js';

const idFromUrl = (u) => Number(u.replace(/\/$/, '').split('/').pop());
// Names in the API use hyphens; people type spaces. Compare both loosely.
const loose = (s) => s.toLowerCase().replace(/[-\s]+/g, ' ').trim();
const itemSprite = (name) =>
  `https://raw.githubusercontent.com/PokeAPI/sprites/master/sprites/items/${name}.png`;
const DMG = { physical: 'Phys', special: 'Spec', status: 'Stat' };

let moveIndex = null;
let itemIndex = null;

const TABS = [
  { id: 'pokemon', label: 'Pokémon' },
  { id: 'moves', label: 'Moves' },
  { id: 'items', label: 'Items' },
];

/**
 * Unified lookup for Pokémon, moves and items. Pokémon come from the bundled
 * snapshot (offline); moves and items lazy-load a name index from PokéAPI
 * (then cached by the service worker) and fetch per-entry detail on demand.
 */
export async function SearchView() {
  const snap = await loadSnapshot();
  const view = el('section', { class: 'view search' });

  let tab = TABS.some((t) => t.id === ui.get().searchTab) ? ui.get().searchTab : 'pokemon';
  let query = ui.get().searchQuery || '';
  let enrichTimer = null;
  let runToken = 0;

  const input = el('input', {
    class: 'search__input',
    type: 'search',
    value: query,
    oninput: (e) => {
      query = e.target.value;
      ui.set({ searchQuery: query });
      run();
    },
  });

  const seg = el(
    'div',
    { class: 'seg' },
    ...TABS.map((t) =>
      el(
        'button',
        {
          class: `seg__btn${t.id === tab ? ' is-active' : ''}`,
          type: 'button',
          onclick: () => {
            tab = t.id;
            ui.set({ searchTab: t.id });
            [...seg.children].forEach((b, i) => b.classList.toggle('is-active', TABS[i].id === tab));
            syncPlaceholder();
            run();
          },
        },
        t.label,
      ),
    ),
  );

  const note = el('p', { class: 'search__note' });
  const results = el('div', { class: 'search__results' });

  function syncPlaceholder() {
    input.placeholder =
      tab === 'pokemon' ? 'Name, number or type…' : tab === 'moves' ? 'Move name…' : 'Item name…';
    const st = settings.get();
    note.textContent =
      tab === 'pokemon'
        ? `Every Pokémon, any game. Opening one shows it for ${
            st.versionGroup === 'all' ? 'all games' : prettify(st.versionGroup)
          }.`
        : tab === 'moves'
          ? 'Every move in the series.'
          : 'Every item in the series.';
  }

  view.append(
    el('header', { class: 'view__header' }, el('h1', {}, 'Search'), note),
    seg,
    input,
    results,
  );
  syncPlaceholder();

  // ---- renderers -------------------------------------------------
  function renderPokemon(q) {
    const style = settings.get().spriteStyle;
    const matches = snap.species
      .filter(
        (s) =>
          loose(s.name).includes(q) ||
          String(s.id) === q ||
          (s.types || []).some((t) => t === q),
      )
      .slice(0, 60);
    if (!matches.length) return void results.append(el('p', { class: 'search__empty' }, 'No matches.'));
    for (const s of matches) {
      const e = entry(s.id);
      results.append(
        el(
          'a',
          { class: `search__row${e.caught ? ' is-caught' : ''}`, href: `#/pokemon/${s.id}` },
          Sprite(s.id, { style, alt: s.name, size: 52 }),
          el('span', { class: 'search__num' }, `#${String(s.id).padStart(4, '0')}`),
          el('span', { class: 'search__name' }, s.name.replace(/-/g, ' ')),
          el('span', { class: 'search__types' }, ...(s.types || []).map(TypeChip)),
        ),
      );
    }
  }

  async function renderMoves(q, token) {
    if (!moveIndex) {
      results.append(el('p', { class: 'search__empty' }, 'Loading moves…'));
      try {
        moveIndex = (await getMoveIndex()).results;
      } catch {
        if (token === runToken) results.textContent = 'Move list unavailable offline.';
        return;
      }
      if (token !== runToken) return; // superseded by a newer query/tab
      clear(results);
    }
    const matches = moveIndex.filter((m) => loose(m.name).includes(q)).slice(0, 80);
    if (!matches.length) return void results.append(el('p', { class: 'search__empty' }, 'No matches.'));

    const metas = new Map();
    for (const m of matches) {
      const meta = el('span', { class: 'search__types' });
      metas.set(m.name, meta);
      results.append(
        el(
          'a',
          { class: 'search__row search__row--slim', href: `#/move/${idFromUrl(m.url)}` },
          el('span', { class: 'search__name' }, m.name.replace(/-/g, ' ')),
          meta,
        ),
      );
    }
    // Enrich a short result set with type / class / power after a pause.
    clearTimeout(enrichTimer);
    if (matches.length <= 24) {
      enrichTimer = setTimeout(() => {
        mapLimit(matches, 6, async (m) => {
          try {
            const d = await getMove(idFromUrl(m.url));
            const meta = metas.get(m.name);
            if (!meta.isConnected) return;
            meta.append(
              TypeChip(d.type.name),
              el('span', { class: 'moverow__cat', dataset: { cat: d.damage_class?.name || '' } },
                DMG[d.damage_class?.name] || '—'),
              el('span', { class: 'search__num' }, d.power != null ? `${d.power} pw` : ''),
            );
          } catch {
            /* leave bare */
          }
        });
      }, 220);
    }
  }

  async function renderItems(q, token) {
    if (!itemIndex) {
      results.append(el('p', { class: 'search__empty' }, 'Loading items…'));
      try {
        itemIndex = (await getItemIndex()).results;
      } catch {
        if (token === runToken) results.textContent = 'Item list unavailable offline.';
        return;
      }
      if (token !== runToken) return;
      clear(results);
    }
    const matches = itemIndex.filter((it) => loose(it.name).includes(q)).slice(0, 80);
    if (!matches.length) return void results.append(el('p', { class: 'search__empty' }, 'No matches.'));
    for (const it of matches) {
      const icon = el('img', {
        class: 'search__item-icon',
        loading: 'lazy',
        alt: '',
        src: itemSprite(it.name),
      });
      icon.addEventListener('error', () => icon.remove(), { once: true });
      results.append(
        el(
          'a',
          { class: 'search__row', href: `#/item/${idFromUrl(it.url)}` },
          icon,
          el('span', { class: 'search__name' }, it.name.replace(/-/g, ' ')),
        ),
      );
    }
  }

  function run() {
    const token = ++runToken;
    const q = loose(query);
    clear(results);
    if (tab === 'pokemon') {
      if (q) renderPokemon(q);
      return;
    }
    if (!q) return;
    (tab === 'moves' ? renderMoves : renderItems)(q, token);
  }

  run();
  requestAnimationFrame(() => window.scrollTo(0, ui.get().searchScroll || 0));
  onTeardown(view, () => {
    clearTimeout(enrichTimer);
    ui.set({ searchScroll: window.scrollY });
  });

  return view;
}