import superjson from "superjson";
import { schema, type OutputType } from "./identify_POST.schema";

type AudDResult = {
  artist?: string;
  title?: string;
  album?: string;
  release_date?: string;
  label?: string;
  timecode?: string;
  song_link?: string;
  spotify?: {
    uri?: string;
    track_number?: number;
    disc_number?: number;
    external_ids?: { isrc?: string };
    external_urls?: { spotify?: string };
    album?: { images?: Array<{ url?: string }> };
  };
};

type AudDResponse = {
  status?: string;
  result?: AudDResult | null;
  error?: { error_message?: string };
};

export async function handle(request: Request) {
  try {
    const apiToken = process.env.AUDD_API_TOKEN;
    if (!apiToken) {
      return new Response(
        superjson.stringify({ error: "Music recognition is not connected yet." }),
        { status: 503 },
      );
    }

    const incoming = await request.formData();
    const parsed = schema.parse({ file: incoming.get("file") });
    const file = parsed.file;

    const outgoing = new FormData();
    outgoing.append("api_token", apiToken);
    outgoing.append("file", file, file.name);
    outgoing.append("return", "spotify,musicbrainz");

    const response = await fetch("https://api.audd.io/", {
      method: "POST",
      body: outgoing,
    });

    if (!response.ok) {
      return new Response(
        superjson.stringify({ error: `Recognition service returned HTTP ${response.status}.` }),
        { status: 502 },
      );
    }

    const body = (await response.json()) as AudDResponse;
    if (body.status !== "success") {
      const detail = body.error?.error_message || "";
      if (detail.toLowerCase().includes("audio fingerprint")) {
        return new Response(superjson.stringify({ matched: false } satisfies OutputType));
      }
      return new Response(
        superjson.stringify({
          error: detail || "Recognition service could not process this file.",
        }),
        { status: 502 },
      );
    }

    if (!body.result) {
      return new Response(superjson.stringify({ matched: false } satisfies OutputType));
    }

    const match = body.result;
    const artworkUrl = match.spotify?.album?.images?.find((image) => image.url)?.url;
    const result: OutputType = {
      matched: true,
      title: match.title,
      artist: match.artist,
      album: match.album,
      releaseDate: match.release_date,
      label: match.label,
      timecode: match.timecode,
      songLink: match.song_link,
      artworkUrl,
      spotifyUri: match.spotify?.uri,
      spotifyUrl: match.spotify?.external_urls?.spotify,
      trackNumber: match.spotify?.track_number,
      discNumber: match.spotify?.disc_number,
      isrc: match.spotify?.external_ids?.isrc,
    };

    return new Response(superjson.stringify(result));
  } catch (error) {
    const message = error instanceof Error ? error.message : "Unable to identify audio.";
    return new Response(superjson.stringify({ error: message }), { status: 400 });
  }
}