// 特殊文件夹图片接口。基址与 photos.ts 一致。
const API_BASE =
  (import.meta.env.VITE_API_BASE as string | undefined) ?? 'http://localhost:8080'

function authHeaders(token: string): Record<string, string> {
  return { Authorization: `Bearer ${token}` }
}

/** 检查文件夹是否已注册（登录前，无鉴权） */
export async function checkFolder(name: string): Promise<boolean> {
  try {
    const res = await fetch(`${API_BASE}/api/web/folder`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ name }),
    })
    if (!res.ok) return false
    return ((await res.json()) as { ok: boolean }).ok
  } catch {
    return false
  }
}

export interface FolderPhotoItem {
  id: string
}

export interface FolderPhotoList {
  items: FolderPhotoItem[]
  totalBytes: number
  overQuota: boolean
}

/** 上传失败的可区分原因 */
export type UploadError = 'too-large' | 'bad-type' | 'failed'

/** 列出文件夹内所有图片，含配额信息 */
export async function listFolderPhotos(
  token: string,
  folder: string,
): Promise<FolderPhotoList> {
  const res = await fetch(`${API_BASE}/api/web/folder/${folder}/photos`, {
    headers: authHeaders(token),
  })
  if (res.status === 403) throw new Error('forbidden')
  if (!res.ok) throw new Error(`list failed: ${res.status}`)
  return (await res.json()) as FolderPhotoList
}

/** 上传图片到文件夹，返回服务器分配的 id */
export async function uploadFolderPhoto(
  token: string,
  folder: string,
  dataUrl: string,
): Promise<string> {
  const res = await fetch(`${API_BASE}/api/web/folder/${folder}/photos`, {
    method: 'POST',
    headers: { ...authHeaders(token), 'Content-Type': 'application/json' },
    body: JSON.stringify({ dataUrl }),
  })
  if (res.ok) return ((await res.json()) as { id: string }).id
  if (res.status === 403) throw new Error('forbidden')
  const reason: UploadError =
    res.status === 413
      ? 'too-large'
      : res.status === 415
        ? 'bad-type'
        : 'failed'
  throw new Error(reason)
}

/** 删除文件夹内图片 */
export async function deleteFolderPhoto(
  token: string,
  folder: string,
  id: string,
): Promise<void> {
  const res = await fetch(`${API_BASE}/api/web/folder/${folder}/photos/${id}`, {
    method: 'DELETE',
    headers: authHeaders(token),
  })
  if (res.status === 403) throw new Error('forbidden')
  if (!res.ok && res.status !== 404) throw new Error(`delete failed: ${res.status}`)
}

/** 获取文件夹内图片的 objectURL（调用方负责释放） */
export async function fetchFolderPhotoUrl(
  token: string,
  folder: string,
  id: string,
): Promise<string> {
  const res = await fetch(`${API_BASE}/api/web/folder/${folder}/photos/${id}`, {
    headers: authHeaders(token),
  })
  if (res.status === 403) throw new Error('forbidden')
  if (!res.ok) throw new Error(`get failed: ${res.status}`)
  return URL.createObjectURL(await res.blob())
}