const API_BASE = process.env.NEXT_PUBLIC_API_URL || "http://localhost:8000";

async function fetchWithAuth(
  url: string,
  options: RequestInit = {},
  token?: string
) {
  const headers: Record<string, string> = {
    "Content-Type": "application/json",
    ...((options.headers as Record<string, string>) || {}),
  };
  if (token) {
    headers["Authorization"] = `Bearer ${token}`;
  }
  const res = await fetch(`${API_BASE}${url}`, { ...options, headers });

  if (res.status === 401) {
    if (typeof window !== "undefined") {
      window.location.href = "/login";
    }
    throw new Error("登录已过期，请重新登录");
  }

  if (!res.ok) {
    let errorDetail = `请求失败 (HTTP ${res.status})`;
    try {
      const error = await res.json();
      errorDetail = error.detail || error.message || errorDetail;
    } catch {
      // 解析失败，使用默认错误信息
    }
    throw new Error(errorDetail);
  }

  if (res.status === 204) {
    return null;
  }

  return res.json();
}

export const api = {
  auth: {
    register: (data: { name: string; email: string; password: string }) =>
      fetchWithAuth("/api/v1/auth/register", {
        method: "POST",
        body: JSON.stringify(data),
      }),
    login: (data: { email: string; password: string }) =>
      fetchWithAuth("/api/v1/auth/login", {
        method: "POST",
        body: JSON.stringify(data),
      }),
    getMe: (token: string) => fetchWithAuth("/api/v1/auth/me", {}, token),
  },
  queries: {
    list: (token: string) => fetchWithAuth("/api/v1/queries/", {}, token),
    create: (token: string, data: unknown) =>
      fetchWithAuth("/api/v1/queries/", { method: "POST", body: JSON.stringify(data) }, token),
    update: (token: string, id: string, data: unknown) =>
      fetchWithAuth(`/api/v1/queries/${id}`, { method: "PUT", body: JSON.stringify(data) }, token),
    delete: (token: string, id: string) =>
      fetchWithAuth(`/api/v1/queries/${id}`, { method: "DELETE" }, token),
    runNow: (token: string, id: string) =>
      fetchWithAuth(`/api/v1/queries/${id}/run-now`, { method: "POST" }, token),
  },
  citations: {
    list: (token: string, params?: string) =>
      fetchWithAuth(`/api/v1/citations/${params ? `?${params}` : ""}`, {}, token),
    getStats: (token: string) => fetchWithAuth("/api/v1/citations/stats/", {}, token),
  },
  reports: {
    exportCSV: (token: string, queryId?: string) => {
      const query = queryId ? `?query_id=${queryId}` : "";
      return fetchWithAuth(`/api/v1/reports/export/csv${query}`, {}, token);
    },
  },
};