import { waitForSlot } from "./rate-limiter";

const TIKHUB_BASE_URL = "https://api.tikhub.io";

// Runtime API Key (set via POST /api/settings)
let runtimeApiKey: string | null = null;

export function setRuntimeApiKey(key: string) {
  runtimeApiKey = key;
}

export function getApiKey(): string | null {
  return runtimeApiKey || process.env.TIKHUB_API_KEY || null;
}

export async function tikhubFetch<T>(
  endpoint: string,
  params?: Record<string, string>,
  method: "GET" | "POST" = "GET",
  body?: Record<string, unknown>
): Promise<T> {
  const apiKey = getApiKey();
  if (!apiKey) {
    throw new TikHubError(401, "API Key 未配置，请在设置页面配置 TikHub API Key");
  }

  await waitForSlot();

  const url = new URL(endpoint, TIKHUB_BASE_URL);
  if (params) {
    Object.entries(params).forEach(([k, v]) => url.searchParams.set(k, v));
  }

  const res = await fetch(url.toString(), {
    method,
    headers: {
      Authorization: `Bearer ${apiKey}`,
      "Content-Type": "application/json",
    },
    ...(method === "POST" ? { body: JSON.stringify(body || {}) } : {}),
  });

  if (!res.ok) {
    if (res.status === 401) {
      throw new TikHubError(401, "API Key 无效，请检查配置");
    }
    if (res.status === 429) {
      throw new TikHubError(429, "请求过于频繁，请稍后重试");
    }
    throw new TikHubError(res.status, `TikHub API 错误: ${res.status}`);
  }

  const json = await res.json();

  // TikHub wraps all responses in { code, data, ... } envelope
  // Unwrap to return the inner data directly
  if (json?.code !== undefined && json?.data !== undefined) {
    return json.data as T;
  }
  return json as T;
}

export class TikHubError extends Error {
  constructor(
    public statusCode: number,
    message: string
  ) {
    super(message);
    this.name = "TikHubError";
  }
}