/**
 * SPDX-License-Identifier: GPL-3.0-only
 * @mp-source app/modules/indexer/spider/milkie.py @ 3b156a5
 * 对照 MoviePilot v3.2.4 的公开 Milkie API 行为实现。搜索结果不保存含 API Key 的下载地址。
 */
import { SiteError } from "../types.ts";
import { apiRequest, businessError, downloadTorrentFile, isoWithZoneToUtc, isPlainObject, siteBase } from "./common.ts";
import type { SpecializedSiteDefinition, SpecializedSpider, SpecializedTorrent, SpiderSearchQuery } from "./types.ts";

export function milkieSearchParams(query: SpiderSearchQuery): Record<string, string | number> {
  const params: Record<string, string | number> = { pi: query.page ?? 0, ps: 100, oby: "created_at", odir: "desc" };
  if (query.keyword) {
    params.query = query.keyword;
    const category = query.mtype ? { movie: "1", tv: "2", music: "3" }[query.mtype] : undefined;
    if (category) params.categories = category;
  }
  return params;
}

/** Milkie 资源 ID 可能为 UUID；不使用其它站点的数字 ID 提取规则。 */
function milkieId(siteId: string, value: unknown): string {
  const id = String(value ?? "");
  if (!/^[a-zA-Z0-9_-]+$/.test(id)) throw new SiteError(siteId, "not_found", "Milkie 资源 ID 非法");
  return id;
}

export function parseMilkieResult(rows: unknown[], def: SpecializedSiteDefinition): SpecializedTorrent[] {
  return rows.flatMap((row): SpecializedTorrent[] => {
    if (!isPlainObject(row) || row.id == null || !row.releaseName) return [];
    const id = milkieId(def.id, row.id);
    const category = { "1": "电影", "2": "电视剧", "3": "音乐" } as const;
    const result: SpecializedTorrent = {
      title: String(row.releaseName),
      description: id,
      site_release_id: id,
      page_url: `${siteBase(def)}browse/${encodeURIComponent(id)}`,
      category: category[String(row.category) as keyof typeof category] ?? "未知",
      downloadvolumefactor: 0,
      uploadvolumefactor: 1,
    };
    if (row.category != null) result.category_id = String(row.category);
    for (const [source, target] of [
      ["size", "size"],
      ["seeders", "seeders"],
      ["leechers", "peers"],
      ["downloaded", "grabs"],
    ] as const) {
      const value = row[source] == null ? NaN : Number(row[source]);
      if (Number.isFinite(value)) result[target] = value;
    }
    const utc = isoWithZoneToUtc(row.createdAt);
    if (utc) result.pubdate_utc = utc;
    else if (typeof row.createdAt === "string") result.pubdate = row.createdAt;
    if (isPlainObject(row.externals) && typeof row.externals.imdb === "string") result.imdbid = row.externals.imdb;
    return [result];
  });
}

export const milkieSpider: SpecializedSpider = {
  parser: "Milkie",
  credential: "apiKey",
  pageSize: () => 100,
  async search(ctx, query) {
    const key = (await ctx.secret("apiKey", true))!;
    const payload = await apiRequest(ctx, `${siteBase(ctx.def)}api/v1/torrents`, {
      headers: { "x-milkie-auth": key },
      query: milkieSearchParams(query),
    });
    if (!isPlainObject(payload) || !Array.isArray(payload.torrents))
      throw businessError(ctx, "搜索", "Milkie 响应不含 torrents 列表");
    return parseMilkieResult(payload.torrents, ctx.def);
  },
  async resolveDownload(ctx, siteReleaseId) {
    const key = (await ctx.secret("apiKey", true))!;
    const id = milkieId(ctx.def.id, siteReleaseId);
    const url = new URL(`api/v1/torrents/${encodeURIComponent(id)}/torrent`, siteBase(ctx.def));
    url.searchParams.set("key", key);
    return downloadTorrentFile(ctx, url.href);
  },
};