import { prisma } from "@/lib/db";
import { browseReleaseGroups } from "@/lib/musicbrainz";

export async function POST(request: Request, { params }: { params: Promise<{ id: string }> }) {
  const { id } = await params;
  let body: unknown;
  try {
    body = await request.json();
  } catch {
    return Response.json({ error: "invalid JSON" }, { status: 400 });
  }
  const { action } = (body ?? {}) as { action?: unknown };
  if (action !== "follow" && action !== "want" && action !== "dismiss") {
    return Response.json({ error: "action must be follow, want, or dismiss" }, { status: 400 });
  }

  const s = await prisma.discoverySuggestion.findUnique({ where: { id } });
  if (!s) return Response.json({ error: "not found" }, { status: 404 });

  if (action === "dismiss") {
    await prisma.discoverySuggestion.update({ where: { id }, data: { status: "dismissed" } });
    // Dismissing an artist also dismisses its album suggestions, so the whole unified row
    // disappears cleanly instead of leaving the artist's albums stranded.
    if (s.kind === "artist") {
      await prisma.discoverySuggestion.updateMany({
        where: { kind: "album", artistMbid: s.artistMbid, status: "pending" },
        data: { status: "dismissed" },
      });
    }
    return Response.json({ id, status: "dismissed" });
  }

  if (action === "follow") {
    if (s.kind !== "artist") {
      return Response.json({ error: "follow applies to artist suggestions" }, { status: 400 });
    }
    const existing = await prisma.watchedArtist.findUnique({ where: { mbid: s.artistMbid } });
    if (!existing) {
      let releases;
      try {
        releases = await browseReleaseGroups(s.artistMbid);
      } catch {
        return Response.json({ error: "MusicBrainz unavailable" }, { status: 502 });
      }
      const created = await prisma.watchedArtist.create({
        data: { mbid: s.artistMbid, name: s.artistName },
      });
      if (releases.length > 0) {
        await prisma.monitoredRelease.createMany({
          data: releases.map((r) => ({
            watchedArtistId: created.id,
            artistMbid: s.artistMbid,
            artistName: s.artistName,
            rgMbid: r.rgMbid,
            album: r.title,
            primaryType: r.primaryType,
            secondaryTypes: r.secondaryTypes,
            firstReleaseDate: r.firstReleaseDate,
            monitored: false,
          })),
          skipDuplicates: true,
        });
      }
    }
    await prisma.discoverySuggestion.update({ where: { id }, data: { status: "followed" } });
    return Response.json({ id, status: "followed" });
  }

  // action === "want"
  if (s.kind !== "album" || !s.rgMbid) {
    return Response.json({ error: "want applies to album suggestions" }, { status: 400 });
  }
  await prisma.monitoredRelease.upsert({
    where: { rgMbid: s.rgMbid },
    create: {
      artistMbid: s.artistMbid,
      artistName: s.artistName,
      rgMbid: s.rgMbid,
      album: s.album ?? "",
      primaryType: s.primaryType,
      secondaryTypes: s.secondaryTypes,
      firstReleaseDate: s.firstReleaseDate,
      monitored: true,
    },
    update: { monitored: true },
  });
  await prisma.discoverySuggestion.update({ where: { id }, data: { status: "wanted" } });
  return Response.json({ id, status: "wanted" });
}