"use server";

import bcrypt from "bcryptjs";

import { AuthError } from "next-auth";

import { prisma } from "@/lib/db";
import { signIn, signOut } from "@/auth";
import { LoginSchema, SignupSchema } from "@/lib/validation/auth";

export type SignupState = {
  error?: string;
} | undefined;

export type LoginState = {
  error?: string;
} | undefined;

export async function login(
  _prevState: LoginState,
  formData: FormData
): Promise<LoginState> {
  const parsed = LoginSchema.safeParse({
    email: formData.get("email"),
    password: formData.get("password"),
  });

  if (!parsed.success) {
    return { error: parsed.error.issues[0]?.message ?? "Invalid input." };
  }

  try {
    await signIn("credentials", {
      email: parsed.data.email,
      password: parsed.data.password,
      redirectTo: "/",
    });
  } catch (error) {
    if (error instanceof AuthError) {
      return { error: "Incorrect email or password." };
    }
    throw error;
  }
}

export async function signup(
  _prevState: SignupState,
  formData: FormData
): Promise<SignupState> {
  const parsed = SignupSchema.safeParse({
    name: formData.get("name"),
    email: formData.get("email"),
    password: formData.get("password"),
  });

  if (!parsed.success) {
    return { error: parsed.error.issues[0]?.message ?? "Invalid input." };
  }

  const { name, email, password } = parsed.data;

  const existing = await prisma.user.findUnique({ where: { email } });
  if (existing) {
    return { error: "An account with that email already exists." };
  }

  const passwordHash = await bcrypt.hash(password, 12);
  await prisma.user.create({ data: { name, email, passwordHash } });

  try {
    // Signs the user in and redirects to "/" on success. NextAuth throws a
    // framework-handled redirect internally, so nothing after this runs.
    await signIn("credentials", { email, password, redirectTo: "/" });
  } catch (error) {
    if (error instanceof AuthError) {
      return { error: "Account created, but sign-in failed. Try logging in." };
    }
    throw error;
  }
}

export async function logout() {
  await signOut({ redirectTo: "/login" });
}