// 给模型看的人话格式(与控制台 apps/web/app/lib/utils.ts formatBytes、labels.ts formatRelative 同口径):
// 环境层渲染和只读能力的输出(download.list 的 size / progress)共用,避免把原始字节数、ISO 时间交给模型转述。

/** 字节 → "79.4 GB"(1024 进制,与控制台一致);null → null */
export function humanBytes(bytes: number | null | undefined, decimals = 1): string | null {
  if (bytes === null || bytes === undefined || !Number.isFinite(bytes)) return null;
  if (bytes <= 0) return "0 B";
  const sizes = ["B", "KB", "MB", "GB", "TB", "PB"];
  const i = Math.min(Math.floor(Math.log(bytes) / Math.log(1024)), sizes.length - 1);
  return `${Number.parseFloat((bytes / 1024 ** i).toFixed(i === 0 ? 0 : decimals))} ${sizes[i]}`;
}

/** 0..1 → "37%" */
export function humanPercent(ratio: number | null | undefined): string | null {
  if (ratio === null || ratio === undefined || !Number.isFinite(ratio)) return null;
  return `${Math.round(Math.max(0, Math.min(1, ratio)) * 100)}%`;
}

/** 本地日期时间 "09-29 16:12"(按给定时区) */
function clock(d: Date, timeZone?: string): { day: string; time: string } {
  const f = new Intl.DateTimeFormat("zh-CN", {
    ...(timeZone ? { timeZone } : {}),
    year: "numeric",
    month: "2-digit",
    day: "2-digit",
    hour: "2-digit",
    minute: "2-digit",
    hour12: false,
  });
  const p = Object.fromEntries(f.formatToParts(d).map((x) => [x.type, x.value]));
  return { day: `${p.year}-${p.month}-${p.day}`, time: `${p.hour === "24" ? "00" : p.hour}:${p.minute}` };
}

/** 当前时间 "2026-09-30 17:45" */
export function humanNow(now: Date, timeZone?: string): string {
  const c = clock(now, timeZone);
  return `${c.day} ${c.time}`;
}

/**
 * 相对时间:刚刚 / N 分钟前 / N 小时前(当天)/ 昨天 16:12 / N 天前;未来时间写"N 小时后"。
 * 无效或空 → null。
 */
export function humanRelative(iso: string | null | undefined, now: Date, timeZone?: string): string | null {
  if (!iso) return null;
  const t = new Date(iso);
  if (Number.isNaN(t.getTime())) return null;
  const diff = (now.getTime() - t.getTime()) / 1000;
  const abs = Math.abs(diff);
  const suffix = diff >= 0 ? "前" : "后";
  if (abs < 45) return diff >= 0 ? "刚刚" : "马上";
  if (abs < 3600) return `${Math.round(abs / 60)} 分钟${suffix}`;
  const a = clock(t, timeZone);
  const b = clock(now, timeZone);
  if (a.day === b.day) return `${Math.round(abs / 3600)} 小时${suffix}`;
  const yesterday = clock(new Date(now.getTime() - 86400_000), timeZone).day;
  if (diff > 0 && a.day === yesterday) return `昨天 ${a.time}`;
  if (abs < 86400 * 2) return `${Math.round(abs / 3600)} 小时${suffix}`;
  return `${Math.round(abs / 86400)} 天${suffix}`;
}

const KIND_NAMES: Record<string, string> = {
  qbittorrent: "qBittorrent",
  transmission: "Transmission",
  deluge: "Deluge",
  aria2: "Aria2",
  jellyfin: "Jellyfin",
  emby: "Emby",
  plex: "Plex",
  pt: "PT 站",
  public_bt: "公开 BT 站",
  rss_feed: "自定义 RSS 源",
  torznab: "Torznab 索引器",
};

/** 类型代码 → 界面名称(qbittorrent → qBittorrent,pt → PT 站);未知原样返回 */
export function kindName(kind: string): string {
  return KIND_NAMES[kind] ?? kind;
}

const HEALTH_NAMES: Record<string, string> = {
  healthy: "正常",
  degraded: "异常",
  offline: "连不上",
  unknown: "还没检查过",
  failing: "连续失败",
  disabled: "已停用",
};

/** 健康状态 → 人话 */
export function healthName(h: string | null | undefined): string {
  return HEALTH_NAMES[h ?? "unknown"] ?? h ?? "还没检查过";
}

const DOWNLOAD_STATUS: Record<string, string> = {
  queued: "排队中",
  submitting: "提交中",
  downloading: "下载中",
  paused: "已暂停",
  stalled: "无进展",
  completed: "已完成待整理",
  importing: "整理中",
  imported: "已入库",
  failed: "失败",
  removed: "已移除",
  missing: "文件缺失",
};

const SUBSCRIPTION_STATUS: Record<string, string> = {
  active: "追更中",
  paused: "已暂停",
  pending: "待开始",
  completed: "已完成",
  cancelled: "已取消",
};

/** 下载任务状态 → 界面用词;未知原样返回 */
export function downloadStatusName(s: string): string {
  return DOWNLOAD_STATUS[s] ?? s;
}

/** 订阅状态 → 界面用词;未知原样返回 */
export function subscriptionStatusName(s: string): string {
  return SUBSCRIPTION_STATUS[s] ?? s;
}

const ACCOUNT_NAMES: Record<string, string> = {
  active: "登录正常",
  invalid: "凭证无效",
  expired: "登录已失效",
  challenge: "需要人工验证",
  unknown: "登录状态未知",
};

/** 站点账号状态 → 人话 */
export function accountName(s: string): string {
  return ACCOUNT_NAMES[s] ?? s;
}