import { AuthOptions } from "next-auth";
import CredentialsProvider from "next-auth/providers/credentials";
import GoogleProvider from "next-auth/providers/google";
import { PrismaAdapter } from "@next-auth/prisma-adapter";
import bcrypt from "bcryptjs";
import { prisma } from "@/lib/prisma";
import { isAdminEmail } from "@/lib/admin";

// Adapter dipakai untuk persist User + Account saat OAuth (Google).
// Session tetap pakai JWT supaya kompatibel dengan CredentialsProvider.
export const authOptions: AuthOptions = {
  adapter: PrismaAdapter(prisma),
  providers: [
    GoogleProvider({
      clientId: process.env.GOOGLE_CLIENT_ID!,
      clientSecret: process.env.GOOGLE_CLIENT_SECRET!,
      // Auto-link kalau email Google sama dengan email user yang sudah register
      // via Credentials. Aman karena Google selalu memverifikasi email pemilik akun.
      allowDangerousEmailAccountLinking: true,
    }),
    CredentialsProvider({
      name: "credentials",
      credentials: {
        email: { label: "Email", type: "email" },
        password: { label: "Password", type: "password" },
      },
      async authorize(credentials) {
        if (!credentials?.email || !credentials?.password) {
          throw new Error("Email dan password harus diisi");
        }

        const user = await prisma.user.findUnique({
          where: { email: credentials.email },
        });

        if (!user) {
          throw new Error("Email tidak ditemukan");
        }

        if (!user.password) {
          throw new Error("Akun ini terdaftar via Google. Silakan login dengan Google.");
        }

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

        if (!isPasswordValid) {
          throw new Error("Password salah");
        }

        return {
          id: user.id,
          name: user.name,
          email: user.email,
          image: user.image,
        };
      },
    }),
  ],
  session: {
    strategy: "jwt",
  },
  callbacks: {
    async signIn({ user }) {
      // Block suspended user dari sign-in (Credentials + OAuth).
      // Email-based lookup karena `user.id` belum tentu ada untuk first-time
      // OAuth sign-in sebelum adapter persist.
      const email = user.email;
      if (!email) return true;
      const existing = await prisma.user.findUnique({
        where: { email },
        select: { suspended: true },
      });
      if (existing?.suspended) {
        // NextAuth menerjemahkan return false jadi error "AccessDenied".
        return false;
      }
      return true;
    },
    async jwt({ token, user, trigger }) {
      if (user) {
        token.id = user.id;
      }
      // Hidrasi `acceptedTermsAndPrivacy` dari DB:
      // - login pertama (`undefined`)
      // - client memanggil `useSession().update()` setelah accept
      // - token masih `false` → selalu cek DB (mencegah infinite redirect loop
      //   antara middleware dan /accept-terms saat DB sudah true tapi cookie stale)
      if (
        token.id &&
        (trigger === "update" ||
          token.acceptedTermsAndPrivacy === undefined ||
          token.acceptedTermsAndPrivacy === false)
      ) {
        const dbUser = await prisma.user.findUnique({
          where: { id: token.id as string },
          select: { acceptedTermsAndPrivacy: true },
        });
        token.acceptedTermsAndPrivacy = dbUser?.acceptedTermsAndPrivacy ?? false;
      }
      return token;
    },
    async session({ session, token }) {
      if (session.user) {
        session.user.id = token.id as string;
        session.user.acceptedTermsAndPrivacy = token.acceptedTermsAndPrivacy ?? false;
        session.user.isAdmin = isAdminEmail(session.user.email);
      }
      return session;
    },
  },
  pages: {
    signIn: "/login",
  },
  secret: process.env.NEXTAUTH_SECRET,
};