import { FetchError, type FetchOptions, ofetch } from "ofetch";
import type { ValidationIssue } from "@imen/shared";

/** Raw client without auth handling (login / refresh / logout use it directly) */
export const rawApi = ofetch.create({ baseURL: "/api", credentials: "include" });

type AuthHooks = {
  token: () => string;
  refresh: () => Promise<boolean>;
  onExpired: () => void;
};
let hooks: AuthHooks | null = null;

/** Wired by the auth store, which owns the access token */
export const setAuthHooks = (h: AuthHooks) => {
  hooks = h;
};

/**
 * Authenticated request. On 401 it refreshes the access token once (using the httpOnly
 * refresh cookie) and retries; if that fails the session is over.
 */
export async function api<T>(url: string, opts: FetchOptions<"json"> = {}, retried = false): Promise<T> {
  const token = hooks?.token();
  try {
    return await rawApi<T>(url, {
      ...opts,
      headers: { ...(opts.headers as Record<string, string>), ...(token && { Authorization: `Bearer ${token}` }) },
    });
  } catch (e) {
    if (e instanceof FetchError && e.status === 401 && !retried && hooks) {
      if (await hooks.refresh()) return api<T>(url, opts, true);
      hooks.onExpired();
    }
    throw e;
  }
}

interface ApiErrorBody {
  message?: string | string[];
  issues?: ValidationIssue[];
}

export const errorBody = (e: unknown): ApiErrorBody =>
  e instanceof FetchError ? ((e.data as ApiErrorBody | undefined) ?? {}) : {};

/** Human-readable (Persian) error message for notifications */
export function errorMessage(e: unknown): string {
  if (e instanceof FetchError) {
    if (!e.status) return "ارتباط با سرور برقرار نشد";
    const msg = errorBody(e).message;
    if (Array.isArray(msg)) return msg.join("، ");
    if (msg) return msg;
    if (e.status === 413) return "حجم فایل بیش از حد مجاز است";
    if (e.status === 429) return "تعداد درخواست‌ها زیاد است؛ کمی بعد تلاش کنید";
    return `خطای سرور (${e.status})`;
  }
  return "خطای ناشناخته";
}