Frankfurter

/**
 * Frankfurter - generated by OmniStream from Frankfurter's OpenAPI spec.
 * One typed method per endpoint. A single Omni key reaches the API.
 */
const DEFAULT_BASE = "https://grid.skinvaults.online/v1/proxy/frankfurter";

export class FrankfurterError extends Error {
  status: number;
  code?: string;
  constructor(status: number, code: string | undefined, message?: string) {
    super(message || `Frankfurter error ${status}`);
    this.name = "FrankfurterError";
    this.status = status;
    this.code = code;
  }
}

export interface FrankfurterOptions {
  baseUrl?: string;
  fetch?: typeof fetch;
  timeoutMs?: number;
}

export class Frankfurter {
  /** @param token Your OmniStream key (one key for every API). */
  constructor(private token: string, private opts: FrankfurterOptions = {}) {
    if (!token) throw new Error("Frankfurter: token is required");
  }
  rateLimit: { remainingMinute?: number; remainingDay?: number } | null = null;

  private async _request(method: string, path: string, { params, body }: { params?: Record<string, unknown>; body?: unknown } = {}): Promise<any> {
    const f = this.opts.fetch ?? globalThis.fetch;
    const url = new URL((this.opts.baseUrl ?? DEFAULT_BASE).replace(/\/+$/, "") + path);
    if (params) for (const [k, v] of Object.entries(params)) if (v != null) url.searchParams.set(k, String(v));
    const headers: Record<string, string> = { "x-omni-key": this.token };
    if (body !== undefined) headers["content-type"] = "application/json";
    const res = await f(url, { method, headers, body: body !== undefined ? JSON.stringify(body) : undefined });
    this.rateLimit = {
      remainingMinute: Number(res.headers.get("x-ratelimit-remaining-minute")) || undefined,
      remainingDay: Number(res.headers.get("x-ratelimit-remaining-day")) || undefined,
    };
    const data = await res.json().catch(() => ({}));
    if (!res.ok) throw new FrankfurterError(res.status, data?.error?.code, data?.error?.message);
    return data.data ?? data;
  }

  /** Latest exchange rates */
  latestRates(params: { "base"?: string; "symbols"?: string }): Promise<any> {
    return this._request("GET", "/latest", { params });
  }

  /** Historical rates for a date (YYYY-MM-DD) */
  historicalRates(params: { "date": string; "base"?: string }): Promise<any> {
    return this._request("GET", "/{date}", { params });
  }
}

export default Frankfurter;