import NextAuth, { NextAuthConfig } from "next-auth"
import CredentialsProvider from "next-auth/providers/credentials"
import { PrismaAdapter } from "@auth/prisma-adapter"
import { PrismaClient } from "@prisma/client"
import bcrypt from "bcryptjs"

const prisma = new PrismaClient()

export const authConfig: NextAuthConfig = {
  adapter: PrismaAdapter(prisma),
  providers: [
    CredentialsProvider({
      name: "credentials",
      credentials: {
        email: { label: "Email", type: "email" },
        password: { label: "Password", type: "password" }
      },
      async authorize(credentials) {
        if (!credentials?.email || !credentials?.password) {
          return null
        }

        const user = await prisma.user.findUnique({
          where: {
            email: credentials.email as string
          }
        })

        if (!user || !user.isActive) {
          return null
        }

        const isPasswordValid = await bcrypt.compare(
          credentials.password as string,
          user.password
        )

        if (!isPasswordValid) {
          return null
        }

        return {
          id: user.id.toString(),
          email: user.email,
          name: user.name,
          role: user.role,
        }
      }
    })
  ],
  session: {
    strategy: "jwt"
  },
  callbacks: {
    async jwt({ token, user }) {
      if (user) {
        token.role = user.role
      }
      return token
    },
    async session({ session, token }) {
      if (token) {
        session.user.id = token.sub ?? ""
        session.user.role = token.role as string
      }
      return session
    }
  },
  pages: {
    signIn: "/auth/signin",
  },
  // Kein Fallback-Secret: fehlt NEXTAUTH_SECRET, soll der Start fehlschlagen,
  // statt still mit einem öffentlich bekannten Wert zu signieren.
  secret: process.env.NEXTAUTH_SECRET!
}

export const { handlers, auth, signIn, signOut } = NextAuth(authConfig)