'use server';

import { cookies } from 'next/headers';
import { redirect } from 'next/navigation';

const API_URL = process.env.API_INTERNAL_URL || process.env.NEXT_PUBLIC_API_URL || 'http://localhost:3001';

export interface AuthUser {
  id: string;
  username: string;
  displayName: string | null;
  role: 'SUPER_ADMIN' | 'ADMIN' | 'USER';
  tenantId: string;
  mustChangePassword: boolean;
}

export interface LoginResult {
  success: boolean;
  error?: string;
  user?: AuthUser;
}

/**
 * Login action: POST credentials to API, forward session cookie.
 * In development, the API runs on a different port (3001) so we
 * must manually forward the Set-Cookie header from the API response.
 */
export async function login(formData: FormData): Promise<LoginResult> {
  const username = formData.get('username') as string;
  const password = formData.get('password') as string;
  const rememberMe = formData.get('rememberMe') === 'on';

  if (!username || !password) {
    return { success: false, error: 'invalidCredentials' };
  }

  try {
    const response = await fetch(`${API_URL}/auth/login`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({ username, password }),
    });

    if (!response.ok) {
      return { success: false, error: 'invalidCredentials' };
    }

    const user: AuthUser = await response.json();

    // Forward the session cookie from the API response to the browser
    const setCookieHeader = response.headers.get('set-cookie');
    if (setCookieHeader) {
      const sessionMatch = setCookieHeader.match(/session=([^;]+)/);
      if (sessionMatch) {
        const cookieStore = await cookies();
        cookieStore.set('session', sessionMatch[1], {
          httpOnly: true,
          secure: process.env.NODE_ENV === 'production',
          sameSite: 'lax',
          ...(rememberMe
            ? { maxAge: 30 * 24 * 60 * 60 }
            : {}),
          path: '/',
        });
      }
    }

    return { success: true, user };
  } catch {
    return { success: false, error: 'networkError' };
  }
}

/**
 * Logout action: POST to API, clear local cookie, redirect to /login.
 */
export async function logout(): Promise<void> {
  const cookieStore = await cookies();
  const session = cookieStore.get('session')?.value;

  try {
    await fetch(`${API_URL}/auth/logout`, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        ...(session ? { Cookie: `session=${session}` } : {}),
      },
      credentials: 'include',
    });
  } catch {
    // Logout should still clear the cookie even if API call fails
  }

  cookieStore.delete('session');
  redirect('/login');
}

/**
 * Fetch the current authenticated user from the API.
 * Uses the session cookie for authentication.
 */
export async function fetchCurrentUser(): Promise<AuthUser | null> {
  const cookieStore = await cookies();
  const session = cookieStore.get('session')?.value;

  if (!session) {
    return null;
  }

  try {
    const response = await fetch(`${API_URL}/auth/me`, {
      headers: {
        Cookie: `session=${session}`,
      },
      credentials: 'include',
      cache: 'no-store',
    });

    if (!response.ok) {
      return null;
    }

    return await response.json();
  } catch {
    return null;
  }
}