middleware.ts

import { NextResponse } from 'next/server'
import type { NextRequest } from 'next/server'
import { unsealData } from 'iron-session'
import type { SessionData } from '@/lib/session'
import { sessionOptions } from '@/lib/session'

export async function middleware(request: NextRequest) {
  const { pathname } = request.nextUrl

  const isAdminPage = pathname.startsWith('/admin') && pathname !== '/admin/login'
  const isAdminApi = pathname.startsWith('/api/admin')

  if (!isAdminPage && !isAdminApi) {
    return NextResponse.next()
  }

  const cookieValue = request.cookies.get(sessionOptions.cookieName)?.value

  if (!cookieValue) {
    if (isAdminApi) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }
    return NextResponse.redirect(new URL('/admin/login', request.url))
  }

  try {
    const session = await unsealData<SessionData>(cookieValue, {
      password: sessionOptions.password as string,
    })

    if (!session.userId) {
      if (isAdminApi) {
        return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
      }
      return NextResponse.redirect(new URL('/admin/login', request.url))
    }
  } catch {
    if (isAdminApi) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }
    return NextResponse.redirect(new URL('/admin/login', request.url))
  }

  return NextResponse.next()
}

export const config = {
  matcher: ['/admin/:path*', '/api/admin/:path*'],
}