import { fetchAttachmentDownloadUrl } from '@/api/business'
import { attachmentFullUrl } from '@/composables/useAttachmentActions'

export { attachmentFullUrl }

export function sanitizeZipPathSegment(value: string, fallback = '未命名') {
  const cleaned = String(value || '')
    .replace(/[\\/:*?"<>|]/g, '_')
    .replace(/\s+/g, ' ')
    .trim()
  return cleaned || fallback
}

export function getAttachmentExtension(file: { fileName?: string; fileUrl?: string }) {
  const raw = String(file.fileName || file.fileUrl?.split('/').pop() || '')
    .split('?')[0]
    .trim()
  const dot = raw.lastIndexOf('.')
  if (dot > 0 && dot < raw.length - 1) {
    return raw.slice(dot + 1).toLowerCase()
  }
  return ''
}

export function resolveAttachmentFileName(
  file: { fileName?: string; fileUrl?: string },
  index = 0
) {
  const name = String(file.fileName || '').trim()
  if (name) return name
  const fromUrl = String(file.fileUrl || '')
    .split('?')[0]
    .split('/')
    .pop()
  if (fromUrl) return fromUrl
  const ext = getAttachmentExtension(file)
  return ext ? `附件${index + 1}.${ext}` : `附件${index + 1}`
}

export function ensureUniqueZipEntryName(name: string, used: Set<string>) {
  if (!used.has(name)) {
    used.add(name)
    return name
  }
  const dot = name.lastIndexOf('.')
  const base = dot > 0 ? name.slice(0, dot) : name
  const ext = dot > 0 ? name.slice(dot) : ''
  let n = 2
  while (used.has(`${base}(${n})${ext}`)) n += 1
  const unique = `${base}(${n})${ext}`
  used.add(unique)
  return unique
}

export function formatZipDateStamp(date = new Date()) {
  const y = date.getFullYear()
  const m = String(date.getMonth() + 1).padStart(2, '0')
  const d = String(date.getDate()).padStart(2, '0')
  return `${y}${m}${d}`
}

export async function fetchAttachmentBlob(
  fileUrl: string,
  fileName: string,
  options?: { signal?: AbortSignal }
) {
  const url = String(fileUrl || '').trim()
  if (!url) return null
  try {
    const res = await fetchAttachmentDownloadUrl({ fileUrl: url, fileName })
    if (res?.downloadUrl) {
      const response = await fetch(res.downloadUrl, { signal: options?.signal })
      if (response.ok) return await response.blob()
    }
  } catch (err) {
    if (options?.signal?.aborted) throw err
  }
  const href = attachmentFullUrl(url)
  if (!href) return null
  try {
    const response = await fetch(href, { signal: options?.signal })
    if (response.ok) return await response.blob()
  } catch (err) {
    if (options?.signal?.aborted) throw err
    return null
  }
  return null
}