// KnowFirm TypeScript SDK — STARTER (thin fetch client generated from openapi/openapi.yaml).
// Finalize/replace via the `api-sdk-client-generation` skill once the foundation app is live
// (typed models, retries, pagination). Kept minimal and dependency-free for now.
//
//   const kf = new KnowFirm({ apiKey: process.env.KNOWFIRM_KEY! });
//   const biz = await kf.business({ name: "bank of america" });

export interface KnowFirmOptions { apiKey: string; baseUrl?: string; fetchImpl?: typeof fetch }
export interface BusinessQuery { ein?: string; lei?: string; cik?: string; cert?: string; ticker?: string; name?: string }

export class KnowFirmError extends Error {
  constructor(public status: number, public body: unknown) { super(`KnowFirm API error ${status}`); }
}

export class KnowFirm {
  private apiKey: string;
  private baseUrl: string;
  private fetchImpl: typeof fetch;
  constructor(opts: KnowFirmOptions) {
    this.apiKey = opts.apiKey;
    this.baseUrl = (opts.baseUrl ?? "https://api.knowfirm.com").replace(/\/$/, "");
    this.fetchImpl = opts.fetchImpl ?? fetch;
  }

  private async request<T>(method: string, path: string, opts: { query?: Record<string, string | number | undefined>; body?: unknown } = {}): Promise<T> {
    const url = new URL(this.baseUrl + path);
    for (const [k, v] of Object.entries(opts.query ?? {})) if (v !== undefined) url.searchParams.set(k, String(v));
    const res = await this.fetchImpl(url.toString(), {
      method,
      headers: { "X-API-Key": this.apiKey, ...(opts.body ? { "Content-Type": "application/json" } : {}) },
      body: opts.body ? JSON.stringify(opts.body) : undefined,
    });
    const data = await res.json().catch(() => ({}));
    if (!res.ok) throw new KnowFirmError(res.status, data);
    return data as T;
  }

  health() { return this.request<unknown>("GET", "/v1/health"); }
  /** Resolve one business by ein | lei | cik | cert | ticker | name. Returns null on 404. */
  async business(q: BusinessQuery) {
    try { return await this.request<unknown>("GET", "/v1/business", { query: q as Record<string, string | undefined> }); }
    catch (e) { if (e instanceof KnowFirmError && e.status === 404) return null; throw e; }
  }
  search(q: string, limit = 10) { return this.request<unknown[]>("GET", "/v1/business/search", { query: { q, limit } }); }
  screening(input: { name: string; country?: string; address?: string }) { return this.request<unknown>("POST", "/v1/screening", { body: input }); }
  enrich(items: BusinessQuery[]) { return this.request<unknown>("POST", "/v1/enrich", { body: { items } }); }
}