import NextAuth from "next-auth";
import Credentials from "next-auth/providers/credentials";
import MicrosoftEntra from "next-auth/providers/microsoft-entra-id";
import bcrypt from "bcryptjs";
import { db } from "@/lib/db";
import { loginSchema } from "@/lib/validations/user";
import type { Role } from "@prisma/client";

export const { handlers, auth, signIn, signOut } = NextAuth({
  trustHost: true,
  session: { strategy: "jwt" },
  pages: {
    signIn: "/login",
    error: "/login",
  },
  providers: [
    MicrosoftEntra({
      clientId: process.env.AZURE_AD_CLIENT_ID!,
      clientSecret: process.env.AZURE_AD_CLIENT_SECRET!,
      // Restricts sign-in to Pelagia Marine's M365 tenant. Without this,
      // any Microsoft account (personal or other org) could authenticate.
      issuer: `https://login.microsoftonline.com/${process.env.AZURE_AD_TENANT_ID}/v2.0`,
    }),
    Credentials({
      credentials: {
        email: { label: "Email", type: "email" },
        password: { label: "Password", type: "password" },
      },
      async authorize(credentials) {
        const parsed = loginSchema.safeParse(credentials);
        if (!parsed.success) return null;

        const user = await db.user.findUnique({
          where: { email: parsed.data.email },
        });
        if (!user || !user.isActive || !user.passwordHash) return null;

        const valid = await bcrypt.compare(parsed.data.password, user.passwordHash);
        if (!valid) return null;

        return { id: user.id, email: user.email, name: user.name, role: user.role };
      },
    }),
  ],
  callbacks: {
    async signIn({ account, profile }) {
      if (account?.provider !== "microsoft-entra-id") return true;

      const email = profile?.email ?? (profile as Record<string, unknown>)?.preferred_username as string;
      if (!email) return false;

      const dbUser = await db.user.findUnique({ where: { email } });
      return !!(dbUser?.isActive);
    },

    async jwt({ token, user, account }) {
      if (account?.provider === "credentials" && user) {
        token.id = user.id;
        token.role = (user as unknown as { role: Role }).role;
      }
      if (account?.provider === "microsoft-entra-id") {
        const email = token.email;
        if (email) {
          const dbUser = await db.user.findUnique({ where: { email } });
          if (dbUser) {
            token.id = dbUser.id;
            token.role = dbUser.role;
          }
        }
      }
      return token;
    },

    session({ session, token }) {
      session.user.id = token.id as string;
      session.user.role = token.role as Role;
      return session;
    },
  },
});

declare module "next-auth" {
  interface Session {
    user: {
      id: string;
      name: string;
      email: string;
      role: Role;
    };
  }
}