import { getOAuthManager } from '../auth/oauth.js';
import type { ApiError } from '../types/index.js';
const BASE_URL = 'https://invoice.moneyforward.com/api/v3';
const RATE_LIMIT = 3; // requests per second
const RATE_WINDOW = 1000; // 1 second in ms
class RateLimiter {
private timestamps: number[] = [];
async waitForSlot(): Promise<void> {
const now = Date.now();
// Remove timestamps older than the rate window
this.timestamps = this.timestamps.filter(t => now - t < RATE_WINDOW);
if (this.timestamps.length >= RATE_LIMIT) {
// Calculate wait time until oldest timestamp expires
const oldestTimestamp = this.timestamps[0];
const waitTime = RATE_WINDOW - (now - oldestTimestamp) + 10; // +10ms buffer
if (waitTime > 0) {
await new Promise(resolve => setTimeout(resolve, waitTime));
// Recursively check again after waiting
return this.waitForSlot();
}
}
this.timestamps.push(Date.now());
}
}
const rateLimiter = new RateLimiter();
export interface RequestOptions {
method?: 'GET' | 'POST' | 'PUT' | 'PATCH' | 'DELETE';
body?: unknown;
params?: Record<string, string | number | undefined>;
}
export class ApiClient {
private async request<T>(endpoint: string, options: RequestOptions = {}): Promise<T> {
await rateLimiter.waitForSlot();
const oauthManager = getOAuthManager();
const accessToken = await oauthManager.getAccessToken();
const url = new URL(`${BASE_URL}${endpoint}`);
// Add query parameters
if (options.params) {
for (const [key, value] of Object.entries(options.params)) {
if (value !== undefined && value !== null && value !== '') {
url.searchParams.set(key, String(value));
}
}
}
const headers: Record<string, string> = {
'Authorization': `Bearer ${accessToken}`,
'Accept': 'application/json',
};
if (options.body) {
headers['Content-Type'] = 'application/json';
}
const response = await fetch(url.toString(), {
method: options.method || 'GET',
headers,
body: options.body ? JSON.stringify(options.body) : undefined,
});
if (!response.ok) {
if (response.status === 429) {
// Rate limit exceeded - wait and retry
const retryAfter = parseInt(response.headers.get('Retry-After') || '1', 10);
await new Promise(resolve => setTimeout(resolve, retryAfter * 1000));
return this.request<T>(endpoint, options);
}
let errorMessage = `API request failed: ${response.status} ${response.statusText}`;
try {
const errorBody = await response.json() as ApiError;
errorMessage = `${errorMessage}: ${errorBody.message || JSON.stringify(errorBody)}`;
} catch {
// ignore JSON parse error
}
throw new Error(errorMessage);
}
// Handle 204 No Content
if (response.status === 204) {
return {} as T;
}
return await response.json() as T;
}
async get<T>(endpoint: string, params?: Record<string, string | number | undefined>): Promise<T> {
return this.request<T>(endpoint, { method: 'GET', params });
}
async post<T>(endpoint: string, body?: unknown): Promise<T> {
return this.request<T>(endpoint, { method: 'POST', body });
}
async put<T>(endpoint: string, body?: unknown): Promise<T> {
return this.request<T>(endpoint, { method: 'PUT', body });
}
async patch<T>(endpoint: string, body?: unknown): Promise<T> {
return this.request<T>(endpoint, { method: 'PATCH', body });
}
async delete<T>(endpoint: string): Promise<T> {
return this.request<T>(endpoint, { method: 'DELETE' });
}
}
// Singleton instance
export const apiClient = new ApiClient();
