// Web + Odysee suggestion enrichment (free APIs, no key required).
// Pure parsers are exported for offline unit tests; fetchers never throw.

const UA = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36';

function webTimeoutMs() {
  const n = Number(process.env.SUGGEST_WEB_TIMEOUT_MS || 4000);
  return Number.isFinite(n) && n > 0 ? Math.min(n, 15000) : 4000;
}

/**
 * Parse an OSJSON response (`["q", ["s1", "s2", ...], ...]`) shared by
 * Bing (`osjson.aspx`) and Google (`client=chrome`). Garbage yields [].
 */
export function parseOsjsonList(text) {
  try {
    const data = JSON.parse(String(text || ''));
    const list = Array.isArray(data) ? data[1] : null;
    if (!Array.isArray(list)) return [];
    return list.map((s) => String(s ?? '').trim()).filter(Boolean);
  } catch {
    return [];
  }
}

/** Bing autocomplete (no key): fr suggestions, up to `limit`. */
export async function fetchBingSuggest(q, { limit = 10, lang = 'fr' } = {}) {
  const query = String(q || '').trim();
  if (query.length < 2) return [];
  try {
    const params = new URLSearchParams({ query, language: String(lang || 'fr') });
    const resp = await fetch(`https://api.bing.com/osjson.aspx?${params.toString()}`, {
      headers: { 'User-Agent': UA, Accept: 'application/json' },
      signal: AbortSignal.timeout(webTimeoutMs()),
    });
    if (!resp.ok) return [];
    return parseOsjsonList(await resp.text()).slice(0, limit);
  } catch {
    return [];
  }
}

/** Google autocomplete, `client=chrome` flavour (no key). Same infra family
 * as the YouTube suggest already used, but generic web suggestions. */
export async function fetchGoogleChromeSuggest(q, { limit = 10, lang = 'fr' } = {}) {
  const query = String(q || '').trim();
  if (query.length < 2) return [];
  try {
    const params = new URLSearchParams({ client: 'chrome', q: query, hl: String(lang || 'fr') });
    const resp = await fetch(`https://suggestqueries.google.com/complete/search?${params.toString()}`, {
      headers: { 'User-Agent': UA },
      signal: AbortSignal.timeout(webTimeoutMs()),
    });
    if (!resp.ok) return [];
    return parseOsjsonList(await resp.text()).slice(0, limit);
  } catch {
    return [];
  }
}

/** Turn an Odysee/LBRY claim `name` slug into a readable suggestion. */
export function humanizeClaimName(name) {
  return String(name || '').replace(/[-_]+/g, ' ').replace(/\s+/g, ' ').trim();
}

/**
 * Parse a Lighthouse (Odysee search API, no key) response into readable
 * video-title suggestions.
 */
export function parseLighthouseList(data, limit = 10) {
  const arr = Array.isArray(data) ? data : [];
  const out = [];
  for (const item of arr) {
    const t = humanizeClaimName(item?.name);
    if (t && t.length >= 3) out.push(t);
    if (out.length >= limit) break;
  }
  return out;
}

/** Odysee Lighthouse full-text search (no key): real Odysee video titles. */
export async function fetchOdyseeLighthouseSuggest(q, { limit = 10 } = {}) {
  const query = String(q || '').trim();
  if (query.length < 2) return [];
  try {
    const params = new URLSearchParams({ s: query, size: String(Math.min(20, Math.max(1, limit))), from: '0' });
    const resp = await fetch(`https://lighthouse.odysee.com/search?${params.toString()}`, {
      headers: { 'User-Agent': UA, Accept: 'application/json' },
      signal: AbortSignal.timeout(webTimeoutMs()),
    });
    if (!resp.ok) return [];
    return parseLighthouseList(await resp.json(), limit);
  } catch {
    return [];
  }
}

function normKey(s) {
  return String(s ?? '').trim().toLowerCase().replace(/\s+/g, ' ');
}

/**
 * Combined generic web suggestions (Bing + Google chrome, in parallel),
 * deduplicated (Bing first). Never throws.
 */
export async function fetchWebSuggest(q, { limit = 10, lang = 'fr' } = {}) {
  const query = String(q || '').trim();
  if (query.length < 2) return [];
  const lim = Math.min(20, Math.max(1, Number(limit) || 10));
  try {
    const [bing, chrome] = await Promise.all([
      fetchBingSuggest(query, { limit: lim, lang }),
      fetchGoogleChromeSuggest(query, { limit: lim, lang }),
    ]);
    const seen = new Set();
    const out = [];
    for (const t of [...(bing || []), ...(chrome || [])]) {
      const clean = String(t ?? '').trim();
      if (!clean) continue;
      const k = normKey(clean);
      if (seen.has(k)) continue;
      seen.add(k);
      out.push(clean);
      if (out.length >= lim) break;
    }
    return out;
  } catch {
    return [];
  }
}