import type Database from 'better-sqlite3';
import { listDomains, normalizeDomain } from '../domains/repository';
import { fetchText } from '../http';

export type WebHit = {
  url: string;
  title: string;
  domain: string;
  snippet: string | null;
  thumbnail: string | null;
};

type SearxngResult = {
  url: string;
  title: string;
  content?: string;
  thumbnail?: string;
  img_src?: string;
};

type SearxngResponse = {
  results?: SearxngResult[];
};

function hostnameFromUrl(url: string): string | null {
  try {
    return normalizeDomain(new URL(url).hostname);
  } catch {
    return null;
  }
}

export async function searchWeb(
  db: Database.Database,
  query: string,
  opts: { searxngUrl?: string; limit?: number } = {}
): Promise<WebHit[]> {
  const trimmed = query.trim();
  if (!trimmed) return [];
  const domains = listDomains(db).map((d) => d.domain);
  if (domains.length === 0) return [];

  const searxngUrl = opts.searxngUrl ?? process.env.SEARXNG_URL ?? 'http://localhost:8888';
  const limit = opts.limit ?? 20;
  const siteFilter = domains.map((d) => `site:${d}`).join(' OR ');
  const q = `${trimmed} (${siteFilter})`;
  const endpoint = new URL('/search', searxngUrl);
  endpoint.searchParams.set('q', q);
  endpoint.searchParams.set('format', 'json');
  endpoint.searchParams.set('language', 'de');

  const body = await fetchText(endpoint.toString(), { timeoutMs: 15_000 });
  let parsed: SearxngResponse;
  try {
    parsed = JSON.parse(body) as SearxngResponse;
  } catch {
    throw new Error('SearXNG did not return JSON');
  }
  const results = parsed.results ?? [];
  const allowed = new Set(domains);
  const seen = new Set<string>();
  const hits: WebHit[] = [];
  for (const r of results) {
    const host = hostnameFromUrl(r.url);
    if (!host || !allowed.has(host)) continue;
    if (seen.has(r.url)) continue;
    seen.add(r.url);
    hits.push({
      url: r.url,
      title: r.title,
      domain: host,
      snippet: r.content ?? null,
      thumbnail: r.thumbnail ?? r.img_src ?? null
    });
    if (hits.length >= limit) break;
  }
  return hits;
}