import { onMounted, onUnmounted, ref } from 'vue';

import { apiClient } from '../api/client';
import { relayDtoToDomain } from '../types/mappers/relayDtoMapper';
import type { Relay } from '../types/relay';
import { isNil } from '../utils/isNil';

export function useRelayPolling(intervalMs: number = 2000) {
  const relays = ref<Relay[]>([]);
  const isLoading = ref(false);
  const error = ref<string | null>(null);

  let pollingInterval: number | null = null;

  const fetchData = async () => {
    isLoading.value = true;
    try {
      const { data } = await apiClient.GET('/api/relays');
      relays.value = data?.map(relayDtoToDomain) ?? [];
      error.value = null;
    } catch (err: any) {
      console.error('Polling error:', err);
      error.value = err.message || 'Failed to fetch data';
    } finally {
      isLoading.value = false;
    }
  };

  const startPolling = () => {
    fetchData();
    pollingInterval = window.setInterval(fetchData, intervalMs);
  };

  const stopPolling = () => {
    if (isNil(pollingInterval)) {
      return;
    }
    clearInterval(pollingInterval);
    pollingInterval = null;
  };

  onMounted(startPolling);
  onUnmounted(stopPolling);

  return {
    relays,
    isLoading,
    error,
    refresh: fetchData,
  };
}