tempus/app/src/main/java/com/cappielloantonio/play/viewmodel/SongBottomSheetViewModel.java

package com.cappielloantonio.play.viewmodel;

import android.app.Application;
import android.content.Context;

import androidx.annotation.NonNull;
import androidx.lifecycle.AndroidViewModel;
import androidx.lifecycle.LifecycleOwner;
import androidx.lifecycle.LiveData;
import androidx.lifecycle.MutableLiveData;
import androidx.media3.common.util.UnstableApi;

import com.cappielloantonio.play.model.Album;
import com.cappielloantonio.play.model.Artist;
import com.cappielloantonio.play.model.Media;
import com.cappielloantonio.play.repository.AlbumRepository;
import com.cappielloantonio.play.repository.ArtistRepository;
import com.cappielloantonio.play.repository.SongRepository;
import com.cappielloantonio.play.util.DownloadUtil;
import com.cappielloantonio.play.util.MappingUtil;
import com.cappielloantonio.play.util.PreferenceUtil;

import java.util.Collections;
import java.util.List;

@UnstableApi
public class SongBottomSheetViewModel extends AndroidViewModel {
    private final SongRepository songRepository;
    private final AlbumRepository albumRepository;
    private final ArtistRepository artistRepository;

    private Media song;

    private final MutableLiveData<List<Media>> instantMix = new MutableLiveData<>(null);

    public SongBottomSheetViewModel(@NonNull Application application) {
        super(application);

        songRepository = new SongRepository(application);
        albumRepository = new AlbumRepository(application);
        artistRepository = new ArtistRepository(application);
    }

    public Media getSong() {
        return song;
    }

    public void setSong(Media song) {
        this.song = song;
    }

    public void setFavorite(Context context) {
        if (song.isStarred()) {
            songRepository.unstar(song.getId());
            song.setStarred(false);
        } else {
            songRepository.star(song.getId());
            song.setStarred(true);

            if (PreferenceUtil.getInstance(context).isStarredSyncEnabled()) {
                DownloadUtil.getDownloadTracker(context).download(
                        MappingUtil.mapMediaItem(context, song, false),
                        MappingUtil.mapDownload(song, null, null)
                );
            }
        }
    }

    public LiveData<Album> getAlbum() {
        return albumRepository.getAlbum(song.getAlbumId());
    }

    public LiveData<Artist> getArtist() {
        return artistRepository.getArtist(song.getArtistId());
    }

    public LiveData<List<Media>> getInstantMix(LifecycleOwner owner, Media media) {
        instantMix.setValue(Collections.emptyList());

        songRepository.getInstantMix(media, 20).observe(owner, instantMix::postValue);

        return instantMix;
    }
}