import { z } from "zod";
import { readJson, readPaging, withApi } from "@/lib/api";
import { getLibrary } from "@/lib/queries";
import { addToLibrary } from "@/lib/library";
import { ensureTitle } from "@/lib/catalog";
import type { EntryStatus, TitleType } from "@/generated/prisma/client";

const STATUSES = ["WATCHING", "PAUSED", "COMPLETED", "DROPPED", "WATCHLIST"] as const;

/** GET /api/v1/bibliothek — Bibliothek lesen, mit denselben Filtern wie im UI. */
export const GET = withApi(async (request, user) => {
  const url = new URL(request.url);
  const { limit, offset } = readPaging(request);

  const status = url.searchParams.get("status");
  const type = url.searchParams.get("typ");

  const items = await getLibrary(user.id, {
    query: url.searchParams.get("q") ?? undefined,
    status: STATUSES.includes(status as EntryStatus) ? (status as EntryStatus) : undefined,
    type: type === "SERIES" || type === "MOVIE" ? (type as TitleType) : undefined,
    genre: url.searchParams.get("genre") ?? undefined,
    tag: url.searchParams.get("tag") ?? undefined,
    provider: url.searchParams.get("dienst") ?? undefined,
    owned: url.searchParams.get("sammlung") === "1" ? true : undefined,
  });

  return {
    total: items.length,
    limit,
    offset,
    items: items.slice(offset, offset + limit),
  };
});

const addSchema = z
  .object({
    titleId: z.string().min(1).optional(),
    tmdbId: z.number().int().positive().optional(),
    type: z.enum(["SERIES", "MOVIE"]).optional(),
    status: z.enum(STATUSES).default("WATCHLIST"),
  })
  .refine((value) => Boolean(value.titleId) || Boolean(value.tmdbId && value.type), {
    message: "Entweder titleId oder tmdbId zusammen mit type angeben.",
  });

/** POST /api/v1/bibliothek — Titel aufnehmen, per interner ID oder TMDB-ID. */
export const POST = withApi(async (request, user) => {
  const body = await readJson(request, addSchema);

  let titleId = body.titleId;
  if (!titleId && body.tmdbId && body.type) {
    const title = await ensureTitle(body.type, body.tmdbId, { region: user.region });
    titleId = title.id;
  }
  if (!titleId) {
    throw new z.ZodError([
      { code: "custom", path: ["titleId"], message: "Kein Titel angegeben." },
    ]);
  }

  const entry = await addToLibrary(user.id, titleId, body.status);
  return { id: entry.id, titleId: entry.titleId, status: entry.status };
});