import Link from "next/link";
import type { Metadata } from "next";
import { requireUser } from "@/lib/auth";
import { getSettings } from "@/lib/settings";
import { env } from "@/lib/env";
import { searchMovies, searchMulti, searchSeries, type TmdbSearchResult } from "@/lib/tmdb";
import { AppShell } from "@/components/AppShell";
import { Poster } from "@/components/Poster";
import { SearchField } from "@/components/SearchField";
import { SearchPendingProvider, SearchResults } from "@/components/SearchPending";

export const metadata: Metadata = { title: "Suchen" };

type Filter = "alle" | "serien" | "filme";

const FILTERS: { key: Filter; label: string }[] = [
  { key: "alle", label: "Alles" },
  { key: "serien", label: "Serien" },
  { key: "filme", label: "Filme" },
];

/** Normalisiert die drei TMDB-Antwortformen auf eine gemeinsame Darstellung. */
function normalize(item: TmdbSearchResult, fallbackType: "tv" | "movie") {
  const type = item.media_type === "tv" || item.media_type === "movie" ? item.media_type : fallbackType;
  const date = type === "tv" ? item.first_air_date : item.release_date;
  return {
    tmdbId: item.id,
    type,
    title: (type === "tv" ? item.name : item.title) ?? item.original_name ?? item.original_title ?? "Ohne Titel",
    overview: item.overview ?? "",
    posterPath: item.poster_path ?? null,
    year: date ? date.slice(0, 4) : null,
    rating: item.vote_average ?? null,
  };
}

export default async function SearchPage({
  searchParams,
}: {
  searchParams: Promise<{ q?: string; typ?: string }>;
}) {
  const user = await requireUser("/suche");
  const settings = await getSettings();

  const params = await searchParams;
  const query = (params.q ?? "").trim();
  const filter: Filter = FILTERS.some((f) => f.key === params.typ) ? (params.typ as Filter) : "alle";

  return (
    <AppShell user={user} instanceName={settings.instanceName}>
      <header className="mb-6">
        <h1 className="text-2xl font-semibold tracking-tight sm:text-3xl">Suchen</h1>
        <p className="mt-1 text-sm text-[var(--fl-muted)]">
          Serien und Filme aus der TMDB-Datenbank — mit Postern, Staffeln und Episoden.
        </p>
      </header>

      <SearchPendingProvider>
        <SearchField initialQuery={query} filter={filter} filters={FILTERS} />

        <p className="mt-3 text-sm text-[var(--fl-faint)]">
          Nichts dabei?{" "}
          <Link href="/titel/neu" className="text-[var(--fl-accent)] underline-offset-4 hover:underline">
            Titel selbst anlegen
          </Link>
        </p>

        <SearchResults>
          <div className="mt-8">
            {!env.tmdb.isConfigured ? (
              <Notice tone="warning">
                Ohne TMDB-Schlüssel kann Flimmer nicht suchen. Trage <code>TMDB_API_KEY</code> in
                der <code>.env</code> ein und starte die Instanz neu.
              </Notice>
            ) : query.length < 2 ? (
              <Notice>Gib mindestens zwei Zeichen ein, um zu suchen.</Notice>
            ) : (
              <Results query={query} filter={filter} />
            )}
          </div>
        </SearchResults>
      </SearchPendingProvider>
    </AppShell>
  );
}

async function Results({ query, filter }: { query: string; filter: Filter }) {
  let items: ReturnType<typeof normalize>[];

  try {
    if (filter === "serien") {
      const data = await searchSeries(query);
      items = data.results.map((item) => normalize(item, "tv"));
    } else if (filter === "filme") {
      const data = await searchMovies(query);
      items = data.results.map((item) => normalize(item, "movie"));
    } else {
      const data = await searchMulti(query);
      items = data.results.map((item) => normalize(item, "movie"));
    }
  } catch (error) {
    return (
      <Notice tone="danger">
        {error instanceof Error ? error.message : "Die Suche bei TMDB ist fehlgeschlagen."}
      </Notice>
    );
  }

  if (items.length === 0) {
    return <Notice>Zu „{query}" hat TMDB nichts gefunden.</Notice>;
  }

  return (
    <>
      <p className="mb-4 text-sm text-[var(--fl-faint)]">
        {items.length} {items.length === 1 ? "Treffer" : "Treffer"} zu „{query}"
      </p>
      <ul className="grid grid-cols-2 gap-4 sm:grid-cols-3 md:grid-cols-4 lg:grid-cols-6">
        {items.map((item) => (
          <li key={`${item.type}-${item.tmdbId}`}>
            <Link
              href={`/tmdb/${item.type === "tv" ? "serie" : "film"}/${item.tmdbId}`}
              className="fl-poster-card group block focus:outline-none"
            >
              <Poster path={item.posterPath} alt={item.title} size="w342" />
              <div className="mt-2 space-y-0.5">
                <p className="line-clamp-2 min-h-[2lh] text-sm font-medium leading-snug group-hover:text-[var(--fl-text)]">
                  {item.title}
                </p>
                <p className="text-xs text-[var(--fl-faint)]">
                  {item.type === "tv" ? "Serie" : "Film"}
                  {item.year ? ` · ${item.year}` : ""}
                </p>
              </div>
            </Link>
          </li>
        ))}
      </ul>
    </>
  );
}

function Notice({
  children,
  tone = "neutral",
}: {
  children: React.ReactNode;
  tone?: "neutral" | "warning" | "danger";
}) {
  const color =
    tone === "warning" ? "var(--fl-warning)" : tone === "danger" ? "var(--fl-danger)" : "var(--fl-muted)";
  return (
    <p
      className="fl-card px-4 py-3 text-sm"
      style={{
        color,
        borderColor:
          tone === "neutral" ? undefined : `color-mix(in oklab, ${color} 45%, transparent)`,
        backgroundColor:
          tone === "neutral" ? undefined : `color-mix(in oklab, ${color} 10%, transparent)`,
      }}
    >
      {children}
    </p>
  );
}