import { z } from "zod";
import { NonNegInt, Timestamp } from "./common.ts";

// C2-A 缓存管理(docs/runbook/cache.md):TMDB 缓存(请求响应 + 识别结果,对照 MP TmdbCache)、图片代理缓存。

export const TmdbCacheKind = z.enum(["request", "recognize"]);
export type TmdbCacheKind = z.infer<typeof TmdbCacheKind>;

/** 一条 TMDB 缓存(对照 MP list_items:识别条目带 tmdbId / 标题 / 年份 / 类型 / 海报) */
export const TmdbCacheItem = z.object({
  kind: TmdbCacheKind,
  key: z.string(),
  expiresAt: Timestamp,
  updatedAt: Timestamp,
  /** jsonb 存储字节数 */
  bytes: NonNegInt,
  /** 识别条目:TMDB id,0 = 负缓存(未识别) */
  tmdbId: z.number().int().nullable(),
  title: z.string().nullable(),
  year: z.string().nullable(),
  mediaType: z.enum(["movie", "tv", "unknown"]).nullable(),
  posterPath: z.string().nullable(),
});
export type TmdbCacheItem = z.infer<typeof TmdbCacheItem>;

export const TmdbCacheQuery = z.object({
  kind: TmdbCacheKind.optional(),
  limit: z.coerce.number().int().min(1).max(5000).default(500),
});

export const TmdbCacheList = z.object({
  items: z.array(TmdbCacheItem),
  counts: z.object({ request: NonNegInt, recognize: NonNegInt }),
  /** 每类条数上限(cache.tmdbMaxSize) */
  maxSize: NonNegInt,
  ttlHours: NonNegInt,
  emptyResultTtlSec: NonNegInt,
});
export type TmdbCacheList = z.infer<typeof TmdbCacheList>;

export const CacheClearResult = z.object({ deleted: NonNegInt });
export type CacheClearResult = z.infer<typeof CacheClearResult>;

/** 图片代理缓存用量 */
export const ImageCacheStatus = z.object({
  /** cache.globalImageCache */
  enabled: z.boolean(),
  /** cache.globalImageCacheDays */
  days: NonNegInt,
  usedBytes: NonNegInt,
  files: NonNegInt,
  dir: z.string(),
});
export type ImageCacheStatus = z.infer<typeof ImageCacheStatus>;

/** TMDB 图片尺寸白名单(与 TMDB configuration.images 一致) */
export const TMDB_IMAGE_SIZES = [
  "w92",
  "w154",
  "w185",
  "w300",
  "w342",
  "w500",
  "w780",
  "w1280",
  "h632",
  "original",
] as const;
export type TmdbImageSize = (typeof TMDB_IMAGE_SIZES)[number];

/** 海报 / 背景图路径 → 图片代理 URL(相对 API_PREFIX 之外的完整路径,前端直接用作 img src) */
export function tmdbImageUrl(path: string | null | undefined, size: TmdbImageSize = "w342"): string | null {
  if (!path) return null;
  const p = path.startsWith("/") ? path.slice(1) : path;
  if (!/^[A-Za-z0-9_-]+\.(jpg|jpeg|png|webp)$/.test(p)) return null;
  return `/api/v1/img/tmdb/${size}/${p}`;
}

// ── 通用缓存(kv_cache)按 region 管理(设置 → 缓存) ──

/** region 名:小写字母、数字、`.`、`_`、`-` */
export const CacheRegionName = z.string().regex(/^[a-z0-9][a-z0-9._-]{0,63}$/, "缓存区名不合法");
export const CacheRegionParam = z.object({ region: CacheRegionName });

export const CacheRegionStat = z.object({
  region: z.string(),
  /** 未过期条目数 */
  entries: NonNegInt,
  /** 已过期、等清理任务删除的条目数 */
  expired: NonNegInt,
  /** 键与值占用字节(pg_column_size 之和,含已过期) */
  bytes: NonNegInt,
  /** 最近一次写入 */
  lastWriteAt: Timestamp.nullable(),
});
export type CacheRegionStat = z.infer<typeof CacheRegionStat>;

export const CacheRegionList = z.object({ items: z.array(CacheRegionStat) });
export type CacheRegionList = z.infer<typeof CacheRegionList>;

/** region → 界面名;精确匹配优先,其次按前缀(`bangumi.*`);都不中返回 null(界面原样显示 region) */
const CACHE_REGION_LABELS: Record<string, string> = {
  "tmdb.request": "TMDB 请求",
  "tmdb.recognize": "TMDB 识别",
  "douban.request": "豆瓣请求",
  "douban.subject": "豆瓣条目",
  "bangumi.request": "Bangumi 请求",
  "bangumi.subject": "Bangumi 条目",
  "meta.subject_miss": "豆瓣 / Bangumi 查无结果",
  "discover.list": "发现列表",
  "site.detail": "站点详情页",
  "identity.detail_ids": "识别抓详情页计数",
  enrich: "元数据补全",
  "enrich.robots": "元数据补全 robots.txt",
  websearch: "网页搜索",
  "websearch.allow": "可读取的网页",
  images: "图片",
};
const CACHE_REGION_PREFIX_LABELS: [string, string][] = [
  ["tmdb.", "TMDB"],
  ["douban.", "豆瓣"],
  ["bangumi.", "Bangumi"],
  ["discover.", "发现"],
  ["site.", "站点"],
  ["enrich.", "元数据补全"],
  ["websearch.", "网页搜索"],
];
export function cacheRegionLabel(region: string): string | null {
  const exact = CACHE_REGION_LABELS[region];
  if (exact) return exact;
  const hit = CACHE_REGION_PREFIX_LABELS.find(([p]) => region.startsWith(p));
  return hit ? `${hit[1]}（${region.slice(hit[0].length)}）` : null;
}