/**
 * Copyright (c) Double Symmetry GmbH
 * Commercial use requires a license. See https://rntp.dev/pricing
 */

import { useEffect, useState } from 'react';
import { AppState } from 'react-native';
import * as TrackPlayer from '../audio';
import { Event } from '../events';
import type { MediaItem } from '../interfaces';

/**
 * Active media item; refreshes on {@link Event.MediaItemTransition} and
 * {@link Event.MediaMetadataChanged} (after native merges stream metadata).
 */
export function useActiveMediaItem(): MediaItem | null {
  const [item, setItem] = useState<MediaItem | null>(() =>
    TrackPlayer.getActiveMediaItem()
  );

  useEffect(() => {
    const transitionSub = TrackPlayer.addEventListener(
      Event.MediaItemTransition,
      (event) => {
        setItem(event.item);
      }
    );
    const metadataSub = TrackPlayer.addEventListener(
      Event.MediaMetadataChanged,
      () => {
        setItem(TrackPlayer.getActiveMediaItem());
      }
    );
    // Android background changes bypass addEventListener (they reach the
    // headless handler instead), so re-read native state on foreground.
    const appStateSub = AppState.addEventListener('change', (status) => {
      if (status === 'active') setItem(TrackPlayer.getActiveMediaItem());
    });
    return () => {
      transitionSub.remove();
      metadataSub.remove();
      appStateSub.remove();
    };
  }, []);

  return item;
}