import type { ApiErrorCode } from "@umt/contracts";
import type { z } from "zod";
import { ApiRequestError, apiFetch, type FetcherArg } from "~/lib/api.ts";

export { ApiRequestError };

/** 请求并用 contracts 的 zod schema 校验 data;失败抛 ApiRequestError(给 react-query 的 error 态) */
export async function apiParsed<S extends z.ZodType>(schema: S, path: string, arg?: FetcherArg): Promise<z.infer<S>> {
  const r = await apiFetch<unknown>(path, arg);
  if (!r.ok) throw new ApiRequestError(r.error.code, r.error.message);
  const parsed = schema.safeParse(r.data);
  if (!parsed.success) {
    const issue = parsed.error.issues[0];
    throw new ApiRequestError(
      "internal" satisfies ApiErrorCode,
      `响应格式不符合接口定义：${issue ? `${issue.path.join(".")} ${issue.message}` : "未知字段"}`,
    );
  }
  return parsed.data;
}

/** 变更请求:返回 data,失败抛错(给 useMutation,由 onError 统一 toast) */
export async function apiMutate<T = unknown>(path: string, arg: FetcherArg = {}): Promise<T> {
  const r = await apiFetch<T>(path, { method: "POST", ...arg });
  if (!r.ok) throw new ApiRequestError(r.error.code, r.error.message);
  return r.data;
}

export const errorCode = (err: unknown): string | null => (err instanceof ApiRequestError ? err.code : null);

/** 端点是否不存在(后端尚未提供) */
export const isMissingEndpoint = (err: unknown) => errorCode(err) === "not_found";

/** 查询字符串:去掉空值 */
export function cleanParams(p: Record<string, string | number | boolean | undefined | null>) {
  const out: Record<string, string | number | boolean> = {};
  for (const [k, v] of Object.entries(p)) if (v !== undefined && v !== null && v !== "") out[k] = v;
  return out;
}

/** 小规模配置集合:跟随游标取齐,保留列表返回形状供选择器与本地分页共用。 */
export async function fetchAllCursorPages<P extends { items: unknown[]; nextCursor?: string | null }>(
  fetchPage: (cursor?: string) => Promise<P>,
): Promise<P> {
  const first = await fetchPage();
  const items = [...first.items];
  const seen = new Set<string>();
  let cursor = first.nextCursor;
  while (cursor) {
    if (seen.has(cursor)) throw new ApiRequestError("internal", "分页游标重复。重试");
    seen.add(cursor);
    const page = await fetchPage(cursor);
    items.push(...page.items);
    cursor = page.nextCursor;
  }
  return { ...first, items, nextCursor: null };
}