middleware.ts

import acceptLanguage from "accept-language"
import { NextRequest, NextResponse } from "next/server"

import { cookieName, fallbackLng, languages } from "@/app/i18n/settings"

acceptLanguage.languages(languages)

export const config = {
  matcher: [
    /*
     * Match all request paths except for the ones starting with:
     * - api (API routes)
     * - _next/static (static files)
     * - _next/image (image optimization files)
     * - favicon.ico (favicon file)
     */
    {
      source: "/((?!api|_next/static|_next/image|favicon.ico).*)",
    },

    // 排除 assets路径
    {
      source: "/((?!assets/).*)",
    },

    // 排除特定文件
    "/((?!sw\\.js).*)",
    "/((?!site\\.webmanifest).*)",

    // 排除以特定字符串开头的路径
    "/((?!icon/).*)",
    "/((?!chrome/).*)",
  ],
}

export function middleware(req: NextRequest): NextResponse {
  // static file  /public/xxx.svg
  if (
    req.nextUrl.pathname.endsWith(".svg") ||
    req.nextUrl.pathname.endsWith(".png") ||
    req.nextUrl.pathname.endsWith(".ico")
  ) {
    return NextResponse.next()
  }

  if (req.nextUrl.pathname.indexOf("icon") > -1 || req.nextUrl.pathname.indexOf("chrome") > -1)
    return NextResponse.next()

  let lng: string | undefined | null
  if (req.cookies.has(cookieName)) lng = acceptLanguage.get(req.cookies.get(cookieName)?.value)
  if (!lng) lng = acceptLanguage.get(req.headers.get("Accept-Language"))
  if (!lng) lng = fallbackLng

  // Redirect if lng in path is not supported
  if (
    !languages.some((loc) => req.nextUrl.pathname.startsWith(`/${loc}`)) &&
    !req.nextUrl.pathname.startsWith("/_next")
  ) {
    const newUrl = new URL(`/${lng}${req.nextUrl.pathname}${req.nextUrl.search}`, req.url)
    return NextResponse.redirect(newUrl)
  }

  if (req.headers.has("referer")) {
    const refererUrl = new URL(req.headers.get("referer") || "")
    const lngInReferer = languages.find((l) => refererUrl.pathname.startsWith(`/${l}`))
    const response = NextResponse.next()
    if (lngInReferer) response.cookies.set(cookieName, lngInReferer)
    return response
  }

  return NextResponse.next()
}