const VOLATILE_IMAGE_HOSTS = new Set([
  'finder.video.qq.com',
]);

const VOLATILE_IMAGE_PATH_PARTS = [
  '/stodownload',
];

const IMAGE_FIELD_KEYS = new Set([
  'avatar',
  'avatarUrl',
  'avatar_url',
  'accountAvatar',
  'authorAvatar',
  'cover',
  'coverUrl',
  'cover_url',
  'thumbnail',
  'thumbnailUrl',
  'thumbnail_url',
]);

function isVolatileRemoteImageUrl(value: string): boolean {
  const trimmed = value.trim();
  if (!trimmed || trimmed.startsWith('data:') || trimmed.startsWith('blob:')) {
    return false;
  }

  try {
    const url = new URL(trimmed);
    const host = url.hostname.toLowerCase();
    const path = url.pathname.toLowerCase();

    if (VOLATILE_IMAGE_HOSTS.has(host) && VOLATILE_IMAGE_PATH_PARTS.some((part) => path.includes(part))) {
      return true;
    }

    return host.endsWith('.video.qq.com') && url.searchParams.has('encfilekey');
  } catch {
    return false;
  }
}

export function getSafeImageSrc(value: string | null | undefined): string | undefined {
  if (!value) return undefined;
  const trimmed = value.trim();
  if (!trimmed || isVolatileRemoteImageUrl(trimmed)) return undefined;
  return trimmed;
}

export function sanitizeApiImageFields<T>(payload: T): T {
  const seen = new WeakSet<object>();

  function visit(value: unknown): unknown {
    if (!value || typeof value !== 'object') return value;
    if (seen.has(value)) return value;
    seen.add(value);

    if (Array.isArray(value)) {
      value.forEach((item) => visit(item));
      return value;
    }

    const record = value as Record<string, unknown>;
    Object.keys(record).forEach((key) => {
      const fieldValue = record[key];
      if (typeof fieldValue === 'string' && IMAGE_FIELD_KEYS.has(key) && isVolatileRemoteImageUrl(fieldValue)) {
        record[key] = '';
        return;
      }
      visit(fieldValue);
    });

    return value;
  }

  return visit(payload) as T;
}