import type { Context } from '@netlify/functions'
import { guardMethod } from '../utils/method.js'
import { fail, ok } from '../utils/http.js'
import { readJson } from '../utils/request.js'
import { prisma } from '../utils/prisma.js'
import { createBridgeSignature } from '../utils/crypto.js'
import { withErrorBoundary } from '../utils/handler.js'

type SupplierTokenRequest = {
  userId?: string
  supplierIdentification?: string
}

type BridgeTokenResponse = {
  resultCode?: number
  message?: string
  accessToken?: string
  refreshToken?: string
  expire?: number
  refreshExpire?: number
  time?: string
}

const normalizeBase = (base: string) => base.replace(/\/$/, '')

export default withErrorBoundary(async (request: Request, _context: Context) => {
  const methodResponse = guardMethod(request, ['POST'])
  if (methodResponse) return methodResponse

  const body = await readJson<SupplierTokenRequest>(request)
  const userId = String(body.userId || '').trim()
  const supplierIdentification = String(body.supplierIdentification || '').trim().toLowerCase()

  if (!userId || !supplierIdentification) {
    return fail('用户信息和供应商唯一标识不能为空')
  }

  const supplier = await prisma.supplierInfo.findUnique({
    where: { supplierIdentification }
  })

  if (!supplier || supplier.deleted === 1) {
    return fail('供应商信息未配置或已停用', 404, 'SUPPLIER_NOT_CONFIGURED')
  }

  const timestamp = String(Date.now())
  const signature = createBridgeSignature(supplier.clientId, supplier.clientSecret, timestamp)
  const apiBase = normalizeBase(process.env.POINTS_MALL_OPEN_API_BASE || '')

  if (!apiBase) {
    return fail('平台积分商城接口地址未配置', 500, 'OPEN_API_BASE_MISSING')
  }

  const response = await fetch(`${apiBase}/connect/token`, {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      supplierId: supplier.supplierId,
      clientId: supplier.clientId,
      clientSecret: supplier.clientSecret,
      sendSha256: signature,
      code: '',
      timestamp
    })
  })

  const tokenPayload = (await response.json().catch(() => ({}))) as BridgeTokenResponse

  if (!response.ok || tokenPayload.resultCode !== 0) {
    return fail(tokenPayload.message || '获取平台授权令牌失败', 502, 'BRIDGE_TOKEN_FAILED')
  }

  return ok({
    supplierIdentification,
    supplierId: supplier.supplierId,
    supplierName: supplier.supplierName,
    userId,
    token: tokenPayload.accessToken,
    accessToken: tokenPayload.accessToken,
    refreshToken: tokenPayload.refreshToken,
    expiresIn: tokenPayload.expire,
    refreshExpiresIn: tokenPayload.refreshExpire,
    issuedAt: tokenPayload.time
  })
})