const initialState = Object.freeze({
  title: '',
  artist: '',
  album: '',
  albumArt: '',
  isPlaying: false,
  progress: 0,
  duration: 0,
});

function mergeState(current, update) {
  return {
    title: update.title ?? current.title,
    artist: update.artist ?? current.artist,
    album: update.album ?? current.album,
    albumArt: update.albumArt ?? current.albumArt,
    isPlaying: update.isPlaying ?? current.isPlaying,
    progress: update.progress ?? current.progress,
    duration: update.duration ?? current.duration,
  };
}

module.exports = { initialState, mergeState };