/**
 * POST /api/accounting/incoming-invoices/upload
 * Multipart: one file per request (the client uploads many in parallel, tracking
 * per-file upload % via XHR). Creates the CUST_IncomingInvoice staging record,
 * stores the PDF in Strapi (attached to that record), and kicks the extraction
 * pipeline in the BACKGROUND with the in-memory buffer (fire-and-forget), so
 * uploads stay fast for large batches.
 */
import refreshTokenHelper from '../../../utils/refreshTokenHelper'
import errorHandlingHelper from '../../../utils/errorHandlingHelper'
import { createInboxDocument, setInboxStrapiFile } from '../../../utils/inbox/inboxDb'
import { getInboxScope, buildInboxCtx } from '../../../utils/inbox/scope'
import { attachToStrapi } from '../../../utils/inbox/strapiAttach'
import { processInboxDocument } from '../../../utils/inbox/processDocument'

const ALLOWED = /pdf|xml|png|jpe?g|tiff?/i

export default defineEventHandler(async (event) => {
  const scope = getInboxScope(event)
  if (!scope.orgId) return { status: 401, message: 'No organization context' }

  // Read the multipart body ONCE (a refresh-retry can't re-read it).
  const form = await readMultipartFormData(event)
  if (!form) return { status: 400, message: 'No file in request' }
  let buf: Buffer | null = null
  let filename = 'invoice.pdf'
  let mime = 'application/pdf'
  for (const part of form) {
    if (['file', 'files', 'attachment'].includes(part.name || '') && part.data?.length) {
      buf = part.data; filename = part.filename || filename; mime = (part as any).type || mime
    }
  }
  if (!buf || buf.length === 0) return { status: 400, message: 'Empty file' }
  if (!ALLOWED.test(mime) && !ALLOWED.test(filename)) return { status: 415, message: 'Unsupported file type (PDF/XML/image only)' }

  // createInboxDocument is the first REST write — safe to retry after refresh
  // (nothing persisted before it). Strapi attach + background run are best-effort.
  const persist = async (token: string) => {
    const ctx = buildInboxCtx(event, token)
    const id = await createInboxDocument(ctx, {
      filename, mimeType: mime, byteSize: buf!.length
    })
    if (!id) return { status: 500, message: 'Could not create inbox record' }
    try {
      const att = await attachToStrapi(event, token, {
        tableName: 'CUST_IncomingInvoice', recordId: id, buffer: buf!, filename, mimeType: mime
      })
      await setInboxStrapiFile(ctx, id, att.fileUrl, att.strapiAttachmentId)
    } catch (e: any) {
      console.warn('[Inbox] PDF Strapi attach failed (record kept):', e?.message || e)
    }
    processInboxDocument(ctx, id, buf!, { mimeType: mime, filename }).catch(() => {})
    return { status: 200, id, filename, fileStatus: 'processing' }
  }

  try {
    return await persist(await getTokenHelper(event))
  } catch (err: any) {
    try {
      return await persist(await refreshTokenHelper(event))
    } catch (error: any) {
      return errorHandlingHelper(err?.data ?? err, error?.data ?? error)
    }
  }
})