import NextAuth from "next-auth";
import type { DefaultSession, NextAuthConfig } from "next-auth";
import Credentials from "next-auth/providers/credentials";
import GitHub from "next-auth/providers/github";
import Google from "next-auth/providers/google";

/**
 * Optional: `pnpm add @auth/drizzle-adapter` then wire DrizzleAdapter + session strategy "database".
 * Using JWT + Credentials/OAuth; `db` is loaded dynamically inside `authorize` (Node route handler only).
 * User lookup uses the postgres.js client from Drizzle (`db.$client`) so we avoid a direct `drizzle-orm` import in this app.
 */

declare module "next-auth" {
  interface Session {
    user: {
      id: string;
    } & DefaultSession["user"];
  }
}

const providers: NextAuthConfig["providers"] = [
  Credentials({
    name: "Email",
    credentials: {
      email: { label: "Email", type: "email" },
      password: { label: "Password", type: "password" },
    },
    async authorize(credentials) {
      const email = credentials?.email as string | undefined;
      const password = credentials?.password as string | undefined;
      if (!email?.trim() || !password) return null;

      const devPassword = process.env.AUTH_DEV_PASSWORD;
      if (!devPassword) {
        console.warn("[auth] AUTH_DEV_PASSWORD is not set; credentials sign-in disabled.");
        return null;
      }
      if (password !== devPassword) return null;

      const { db } = await import("@tasks/database/client");
      const sql = (db as { $client: (t: TemplateStringsArray, ...v: unknown[]) => Promise<unknown[]> })
        .$client;
      const rows = (await sql`
        SELECT id, email, name, avatar_url AS "avatarUrl"
        FROM users
        WHERE lower(email) = lower(${email.trim()})
        LIMIT 1
      `) as { id: string; email: string; name: string | null; avatarUrl: string | null }[];
      const user = rows[0];
      if (!user) return null;

      return {
        id: user.id,
        email: user.email,
        name: user.name ?? undefined,
        image: user.avatarUrl ?? undefined,
      };
    },
  }),
];

if (process.env.AUTH_GITHUB_ID && process.env.AUTH_GITHUB_SECRET) {
  providers.push(
    GitHub({
      clientId: process.env.AUTH_GITHUB_ID,
      clientSecret: process.env.AUTH_GITHUB_SECRET,
    }),
  );
}

if (process.env.AUTH_GOOGLE_ID && process.env.AUTH_GOOGLE_SECRET) {
  providers.push(
    Google({
      clientId: process.env.AUTH_GOOGLE_ID,
      clientSecret: process.env.AUTH_GOOGLE_SECRET,
    }),
  );
}

export const { handlers, auth, signIn, signOut } = NextAuth({
  session: { strategy: "jwt" },
  pages: {
    signIn: "/sign-in",
  },
  providers,
  callbacks: {
    async jwt({ token, user }) {
      if (user?.id) {
        token.id = user.id;
      }
      return token;
    },
    async session({ session, token }) {
      if (session.user && token.id) {
        session.user.id = token.id as string;
      }
      return session;
    },
  },
  trustHost: true,
});