import { redactUrl } from "../../rss/redact";
import type { PromotionType, SitePromotion, SiteRelease } from "../types";
import { parseSiteTime } from "../util";
import type { IndexerDefinition } from "./schema";
import type { SpiderTorrent } from "./spider";

/**
 * MP 系数 → 统一促销类型。MP 只有 downloadvolumefactor/uploadvolumefactor/freedate 三个字段,
 * 类型名由系数组合推出;字段未配置(undefined)时为 unknown。
 */
export function promotionFromFactors(
  dl: number | undefined,
  ul: number | undefined,
  freedate: string | null,
): SitePromotion {
  if (dl === undefined && ul === undefined)
    return { type: "unknown", downloadFactor: null, uploadFactor: null, expiresAt: null };
  const d = dl ?? 1;
  const u = ul ?? 1;
  let type: PromotionType;
  if (d === 0) type = u >= 2 ? "2xfree" : "free";
  else if (d === 0.5) type = u >= 2 ? "2x50%" : "50%";
  else if (d === 0.3) type = "30%";
  else if (d === 1 && u >= 2) type = "2x";
  else if (d === 1 && u === 1) type = "none";
  else type = "unknown";
  return { type, downloadFactor: dl ?? null, uploadFactor: ul ?? null, expiresAt: type === "none" ? null : freedate };
}

/** 从详情链接取站点资源 ID(NexusPHP `details.php?id=`)。 */
export function releaseIdFromUrl(url: string | undefined): string | null {
  if (!url) return null;
  return /[?&]id=(\d+)/.exec(url)?.[1] ?? null;
}

export function categoryName(def: IndexerDefinition, id: string | undefined): string | null {
  if (!id) return null;
  const named = def.umt.categoryNames?.[id];
  if (named) return named;
  for (const k of ["movie", "tv", "music"] as const) {
    const hit = (def.category?.[k] ?? []).find((c) => String(c.id) === id);
    if (hit?.desc) return hit.desc;
  }
  return null;
}

/** SpiderTorrent(MP TorrentInfo 字段)→ SiteRelease。raw 保存完整 MP 字段(enclosure 脱敏)。 */
export function spiderTorrentToRelease(
  t: SpiderTorrent,
  def: IndexerDefinition,
  observedAt: string,
): SiteRelease | null {
  const id = releaseIdFromUrl(t.page_url) ?? releaseIdFromUrl(t.enclosure);
  if (!id || !t.title) return null;
  const tz = def.umt.timezone;
  const freedate = t.freedate ? parseSiteTime(t.freedate, tz) : null;
  const raw: Record<string, unknown> = { ...t };
  if (t.enclosure) raw.enclosure = redactUrl(t.enclosure);
  const release: SiteRelease = {
    siteId: def.id,
    siteReleaseId: id,
    title: t.title,
    category: { id: t.category_id ?? null, name: categoryName(def, t.category_id) },
    sizeBytes: t.size ?? null,
    seeders: t.seeders ?? null,
    leechers: t.peers ?? null,
    snatched: t.grabs ?? null,
    promotion: promotionFromFactors(t.downloadvolumefactor, t.uploadvolumefactor, freedate),
    hr: t.hit_and_run === undefined ? "unknown" : t.hit_and_run,
    uploadedAt: parseSiteTime(t.pubdate, tz),
    detailUrl: t.page_url ?? new URL(`${def.umt.detailPath}?id=${id}`, def.domain).toString(),
    downloadUrl: t.enclosure
      ? redactUrl(t.enclosure)
      : new URL(`${def.umt.downloadPath}?id=${id}`, def.domain).toString(),
    tags: t.labels ?? [],
    raw,
    observedAt,
  };
  if (t.description) release.subtitle = t.description;
  if (t.imdbid) release.imdbId = t.imdbid;
  return release;
}