/**
 * API client utilities for backend communication with JWT handling.
 */

const API_URL = process.env.NEXT_PUBLIC_API_URL || '';

export function getToken(): string | null {
  if (typeof window === 'undefined') return null;
  return localStorage.getItem('token');
}

export function setToken(token: string): void {
  if (typeof window === 'undefined') return;
  localStorage.setItem('token', token);
}

export function removeToken(): void {
  if (typeof window === 'undefined') return;
  localStorage.removeItem('token');
}

export async function apiCall(
  endpoint: string,
  method: string = 'GET',
  body?: any,
  requiresAuth: boolean = true
): Promise<any> {
  const headers: HeadersInit = {
    'Content-Type': 'application/json',
  };

  if (requiresAuth) {
    const token = getToken();
    if (token) {
      headers['Authorization'] = `Bearer ${token}`;
    }
  }

  const options: RequestInit = {
    method,
    headers,
  };

  if (body) {
    options.body = JSON.stringify(body);
  }

  const response = await fetch(`${API_URL}${endpoint}`, options);

  if (!response.ok) {
    const error = await response.json();
    throw new Error(error.detail || 'API request failed');
  }

  if (response.status === 204) {
    return null;
  }

  return response.json();
}