/**
 * React hook for loading and updating global configuration.
 */

import { useCallback, useEffect, useRef, useState } from "react";
import { fetchGlobalConfig, updateGlobalConfig } from "../api/config";
import { handleFetchError, createStringErrorAdapter } from "../utils/fetchError";
import type { GlobalConfig, GlobalConfigUpdate } from "../types/config";

export interface UseGlobalConfigResult {
  config: GlobalConfig | null;
  loading: boolean;
  error: string | null;
  refresh: () => void;
  updateConfig: (update: GlobalConfigUpdate) => Promise<void>;
}

/**
 * Load global configuration and expose update operations.
 */
export function useGlobalConfig(): UseGlobalConfigResult {
  const [config, setConfig] = useState<GlobalConfig | null>(null);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const abortRef = useRef<AbortController | null>(null);

  const load = useCallback((): void => {
    abortRef.current?.abort();
    const ctrl = new AbortController();
    abortRef.current = ctrl;
    setLoading(true);
    setError(null);

    fetchGlobalConfig()
      .then((resp) => {
        if (!ctrl.signal.aborted) {
          setConfig(resp);
        }
      })
      .catch((err: unknown) => {
        if (!ctrl.signal.aborted) {
          handleFetchError(err, createStringErrorAdapter(setError), "Failed to fetch global config");
        }
      })
      .finally(() => {
        if (!ctrl.signal.aborted) {
          setLoading(false);
        }
      });
  }, []);

  useEffect(() => {
    load();
    return (): void => {
      abortRef.current?.abort();
    };
  }, [load]);

  const updateConfig = useCallback(
    async (update: GlobalConfigUpdate): Promise<void> => {
      await updateGlobalConfig(update);
      load();
    },
    [load],
  );

  return { config, loading, error, refresh: load, updateConfig };
}