/** 头像裁切参数：正方形、聚焦面部 */
const AVATAR_CROP = "w=480&h=480&fit=crop&crop=faces&auto=format&q=85";

/**
 * 32 张精选东亚青年人像（约 20 岁档），男女交替。
 * 来源 Unsplash 免费图库，经 asian portrait 检索筛选。
 */
const AVATAR_PHOTO_IDS = [
  "photo-1534528741775-53994a69daeb", // F
  "photo-1542909168-82c3e7fdca5c", // M
  "photo-1594744803329-7837a673c588", // F
  "photo-1681097561932-36d0df02b379", // M
  "photo-1616268164880-673b3ba611bb", // F
  "photo-1720501828093-c792c10e3f0b", // M
  "photo-1534751516642-a1af1ef26a56", // F
  "photo-1542327897-d73f4005b533", // M
  "photo-1542996966-2e31c00bae31", // F
  "photo-1540569014015-19a7be504e3a", // M
  "photo-1696956994811-95c0a29c917c", // F
  "photo-1642060603505-e716140d45d2", // M
  "photo-1619235327941-c0e47a3ac74a", // F
  "photo-1552358155-515e264cb8b8", // M
  "photo-1541823709867-1b206113eafd", // F
  "photo-1507591064344-4c6ce005b128", // M
  "photo-1580489944761-15a19d654956", // F
  "photo-1546567850-8a49d669d37a", // M
  "photo-1610892417845-07f399a903f4", // F
  "photo-1616326431985-b9f89ebc6ab7", // M
  "photo-1524502397800-2ee9a7dfd228", // F
  "photo-1543610892-0b1f7e6d8ac1", // M
  "photo-1573496359142-b8d87734a5a2", // F
  "photo-1537107041341-713aaa2a234c", // M
  "photo-1601455763557-db1aca8d9a2d", // F
  "photo-1503443207922-dff7d543fd0e", // M
  "photo-1521577352947-9bb5871b2487", // F
  "photo-1534471770828-9bde524ee634", // M
  "photo-1544005313-94ddf0286df2", // F
  "photo-1563521779750-d0bb67aa1d23", // M
  "photo-1554151228-14d9def656e4", // F
  "photo-1543132220-3ec99c6094dc", // M
] as const;

export const AVATAR_URLS = AVATAR_PHOTO_IDS.map(
  (id) => `https://images.unsplash.com/${id}?${AVATAR_CROP}`
);

export function avatarForIndex(index: number): string {
  const safeIndex = Number.isFinite(index) ? Math.abs(Math.trunc(index)) : 0;
  return AVATAR_URLS[safeIndex % AVATAR_URLS.length];
}

export function avatarForName(name: string): string {
  const seed = Array.from(name || "NomadCNA").reduce((sum, char) => sum + char.charCodeAt(0), 0);
  return avatarForIndex(seed);
}