// src/lib/auth.ts
import NextAuth from 'next-auth'
import Credentials from 'next-auth/providers/credentials'
import bcrypt from 'bcryptjs'
import { prisma } from './prisma'

export const { handlers, auth, signIn, signOut } = NextAuth({
  providers: [
    Credentials({
      credentials: {
        email: { label: 'Email', type: 'email' },
        password: { label: 'Password', type: 'password' },
      },
      async authorize({ email, password }) {
        if (!email || !password) return null
        const user = await prisma.user.findUnique({ where: { email: String(email) } })
        if (!user?.password) return null
        const ok = await bcrypt.compare(String(password), user.password)
        if (!ok) return null
        return { id: user.id, name: user.name, email: user.email, role: user.role }
      },
    }),
  ],
  callbacks: {
    jwt({ token, user }) {
      if (user) token.role = (user as any).role
      return token
    },
    session({ session, token }) {
      if (session.user) (session.user as any).role = token.role
      return session
    },
  },
  pages: { signIn: '/admin/login' },
})

// src/app/api/auth/[...nextauth]/route.ts
import { handlers } from '@/lib/auth'
export const { GET, POST } = handlers

// src/middleware.ts
import { auth } from '@/lib/auth'
import { NextResponse } from 'next/server'

export default auth((req) => {
  const isAdminRoute = req.nextUrl.pathname.startsWith('/admin')
  const isLoginPage = req.nextUrl.pathname === '/admin/login'

  if (isAdminRoute && !isLoginPage && !req.auth) {
    return NextResponse.redirect(new URL('/admin/login', req.url))
  }
  if (isLoginPage && req.auth) {
    return NextResponse.redirect(new URL('/admin', req.url))
  }
})

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

// src/app/admin/login/page.tsx
'use client'
import { signIn } from 'next-auth/react'
import { useState } from 'react'
import { useRouter } from 'next/navigation'

export default function LoginPage() {
  const [error, setError] = useState('')
  const router = useRouter()

  const handleSubmit = async (e: React.FormEvent<HTMLFormElement>) => {
    e.preventDefault()
    const fd = new FormData(e.currentTarget)
    const result = await signIn('credentials', {
      email: fd.get('email'),
      password: fd.get('password'),
      redirect: false,
    })
    if (result?.error) {
      setError('이메일 또는 비밀번호가 올바르지 않습니다.')
    } else {
      router.push('/admin')
    }
  }

  return (
    <form onSubmit={handleSubmit} className="max-w-sm mx-auto mt-20 space-y-4">
      <h1 className="text-2xl font-bold">관리자 로그인</h1>
      {error && <p className="text-red-400 text-sm">{error}</p>}
      <input name="email" type="email" placeholder="이메일" className="input w-full" />
      <input name="password" type="password" placeholder="비밀번호" className="input w-full" />
      <button type="submit" className="btn-primary w-full">로그인</button>
    </form>
  )
}

import { auth } from '@/lib/auth'
import { redirect } from 'next/navigation'

export default async function AdminLayout({ children }: { children: React.ReactNode }) {
  const session = await auth()
  if (!session) redirect('/admin/login')

  return (
    <div className="flex">
      <Sidebar />
      <main className="flex-1 p-8">{children}</main>
    </div>
  )
}

import bcrypt from 'bcryptjs'

// 저장 시
const hashed = await bcrypt.hash(plainPassword, 12) // cost factor 12

// 검증 시
const match = await bcrypt.compare(plainPassword, hashed)