import { defineEventHandler, getHeader, getRequestURL, getRouterParam, proxyRequest } from 'h3'
import { useRuntimeConfig } from '#imports'
import { getTenantFromContext } from '../../utils/tenant'

function joinURL(base: string, path: string) {
  if (!path) return base
  return base.replace(/\/+$/, '') + '/' + path.replace(/^\/+/, '')
}

/**
 * 文件代理
 * /api/file/[...path] → SaaS 后端文件服务器
 * 隐藏真实文件服务器地址
 */
export default defineEventHandler((event) => {
  const config = useRuntimeConfig()
  const ctx = getTenantFromContext(event, config)
  const fileServerBase = config.public.fileServerBase as string
  const path = getRouterParam(event, 'path') || ''
  const search = getRequestURL(event).search
  const target = joinURL(fileServerBase, path) + search

  const authorization = getHeader(event, 'authorization')

  return proxyRequest(event, target, {
    headers: {
      TenantId: ctx.tenantId,
      ...(authorization ? { Authorization: authorization } : {})
    }
  })
})