import NextAuth from "next-auth";
import Credentials from "next-auth/providers/credentials";
import { compare } from "bcryptjs";
import { z } from "zod";
import { prisma } from "@/lib/prisma";
import { checkRateLimit, AUTH_RATE_LIMITS } from "@/lib/rate-limit";
import authConfig from "./auth.config";

declare module "next-auth" {
  interface Session {
    user: {
      id: string;
      email: string;
      name?: string | null;
      image?: string | null;
      isEmailVerified: boolean;
    };
  }
}

declare module "@auth/core/jwt" {
  interface JWT {
    id: string;
    isEmailVerified: boolean;
  }
}

const loginSchema = z.object({
  email: z.string().email("Invalid email address"),
  password: z.string().min(8, "Password must be at least 8 characters"),
});

export const { handlers, auth, signIn, signOut } = NextAuth({
  ...authConfig,
  providers: [
    Credentials({
      credentials: {
        email: { label: "Email", type: "email" },
        password: { label: "Password", type: "password" },
      },
      async authorize(credentials, request) {
        const parsed = loginSchema.safeParse(credentials);
        if (!parsed.success) return null;

        const { email, password } = parsed.data;
        const ip = (request instanceof Request
          ? request.headers.get("x-forwarded-for")?.split(",")[0]?.trim()
          : undefined) ?? "unknown";

        const rl = await checkRateLimit(`login:${ip}`, AUTH_RATE_LIMITS.login);
        if (!rl.allowed) return null;

        const user = await prisma.user.findUnique({
          where: { email: email.toLowerCase() },
        });
        if (!user) return null;

        const isValid = await compare(password, user.passwordHash);
        if (!isValid) return null;

        return {
          id: user.id,
          email: user.email,
          name: user.name,
        };
      },
    }),
  ],
  callbacks: {
    async jwt({ token, user, trigger }) {
      if (user) {
        token.id = user.id as string;
      }
      if (trigger === "update" || user) {
        const dbUser = await prisma.user.findUnique({
          where: { id: token.id },
          select: { emailVerified: true },
        });
        if (dbUser) {
          token.isEmailVerified = dbUser.emailVerified;
        }
      }
      return token;
    },
    session({ session, token }) {
      session.user.id = token.id;
      session.user.isEmailVerified = token.isEmailVerified;
      return session;
    },
  },
});