export const API_BASE =
  process.env.NEXT_PUBLIC_API_BASE ??
  (process.env.NODE_ENV === "development" ? "http://localhost:8080" : "/admin139");

function uiText(zhText: string, enText: string): string {
  if (typeof window === "undefined") return zhText;
  const lang = window.localStorage.getItem("csp.ui.language");
  return lang === "en" ? enText : zhText;
}

type ApiEnvelope<T> =
  | { ok: true; data?: T;[k: string]: unknown }
  | { ok: false; error?: string;[k: string]: unknown };

export async function apiFetch<T>(
  path: string,
  init?: RequestInit,
  token?: string
): Promise<T> {
  const headers = new Headers(init?.headers);
  if (token) headers.set("Authorization", `Bearer ${token}`);
  if (init?.body && !headers.has("Content-Type")) {
    headers.set("Content-Type", "application/json");
  }

  const method = (init?.method ?? "GET").toUpperCase();
  const retryable = method === "GET" || method === "HEAD";

  let resp: Response;
  try {
    resp = await fetch(`${API_BASE}${path}`, {
      ...init,
      headers,
      cache: "no-store",
    });
  } catch (err) {
    if (!retryable) {
      throw new Error(
        uiText(
          `网络请求失败，请检查后端服务或代理连接（${err instanceof Error ? err.message : String(err)}）`,
          `Network request failed. Please check backend/proxy connectivity (${err instanceof Error ? err.message : String(err)}).`
        )
      );
    }
    await new Promise((resolve) => setTimeout(resolve, 400));
    try {
      resp = await fetch(`${API_BASE}${path}`, {
        ...init,
        headers,
        cache: "no-store",
      });
    } catch (retryErr) {
      throw new Error(
        uiText(
          `网络请求失败，请检查后端服务或代理连接（${retryErr instanceof Error ? retryErr.message : String(retryErr)
          }）`,
          `Network request failed. Please check backend/proxy connectivity (${retryErr instanceof Error ? retryErr.message : String(retryErr)
          }).`
        )
      );
    }
  }

  const text = await resp.text();
  let payload: unknown = null;
  if (text) {
    try {
      payload = JSON.parse(text) as unknown;
    } catch {
      payload = text;
    }
  }

  if (!resp.ok) {
    const msg =
      typeof payload === "object" && payload !== null && "error" in payload
        ? String((payload as { error?: unknown }).error ?? `HTTP ${resp.status}`)
        : `HTTP ${resp.status}`;
    throw new Error(msg);
  }

  if (typeof payload === "object" && payload !== null && "ok" in payload) {
    const env = payload as ApiEnvelope<T>;
    if (!env.ok) {
      throw new Error(env.error ?? "request failed");
    }
    if ("data" in env) return (env.data as T) ?? ({} as T);
    return payload as T;
  }

  return payload as T;
}

export interface RatingHistoryItem {
  type: string;
  created_at: number;
  change: number;
  note: string;
}

export async function listRatingHistory(limit: number = 100): Promise<RatingHistoryItem[]> {
  return apiFetch<RatingHistoryItem[]>(`/api/v1/me/rating-history?limit=${limit}`);
}