api.ts

import { ApiResponse } from '@/types/api';
import { ApiError } from '../errors/ApiError';

export interface RequestOptions {
  method?: 'GET' | 'POST' | 'PUT' | 'PATCH' | 'DELETE';
  body?: object | BodyInit;
  headers?: Record<string, string>;
}

export async function apiFetch<T>(endpoint: string, options: RequestOptions = {}): Promise<T> {
  const headers: Record<string, string> = options.headers ?? {};
  const method = options.method ?? 'GET';
  let response: Response;
  let json: ApiResponse<T>;
  let body: BodyInit | undefined;

  if (method !== 'GET') {
    const b = options.body;
    if (b instanceof FormData || b instanceof Blob || typeof b === 'string') {
      body = b;
    } else {
      headers['Content-Type'] = 'application/json';
      body = JSON.stringify(b ?? {});
    }
  }

  try {
    response = await fetch(`${process.env.NEXT_PUBLIC_API_BASE_URL}${endpoint}`, {
      method: method,
      headers: headers,
      body: body,
      credentials: 'include',
    });
  } catch {
    throw new ApiError({ code: 'NETWORK_ERROR', message: 'Failed to connect to server.', status: 0, cause: 'network' });
  }

  try {
    json = (await response.json()) as ApiResponse<T>;
  } catch {
    throw new ApiError({
      code: 'INVALID_JSON',
      message: 'Invalid JSON response from server.',
      status: response.status,
      cause: 'json',
    });
  }

  if (!json.success) {
    throw new ApiError({
      code: json?.error?.code ?? 'API_ERROR',
      message: json?.message ?? response.statusText,
      details: json?.error?.details,
      status: response.status,
      cause: 'api',
    });
  }

  return json.data;
}