subsonic-tui/internal/playback/mpris.go

package playback

import (
	"encoding/base32"
	"fmt"

	"git.dayanhub.com/sagi/subsonic-tui/internal/client"
	"github.com/delucks/go-subsonic"
	"github.com/godbus/dbus/v5"
	"github.com/quarckster/go-mpris-server/pkg/events"
	"github.com/quarckster/go-mpris-server/pkg/server"
	mprisTypes "github.com/quarckster/go-mpris-server/pkg/types"
)

const (
	mprisPlayerNmae = "SubsonicTUI"
	mprisNoTrack    = "/org/mpris/MediaPlayer2/TrackList/NoTrack"
)

type mprisRoot struct{}

func (r mprisRoot) Raise() error {
	return nil
}

func (r mprisRoot) Quit() error {
	return nil
}

func (r mprisRoot) CanQuit() (bool, error) {
	return true, nil
}

func (r mprisRoot) CanRaise() (bool, error) {
	return false, nil
}

func (r mprisRoot) HasTrackList() (bool, error) {
	return false, nil
}

func (r mprisRoot) Identity() (string, error) {
	return mprisPlayerNmae, nil
}

func (r mprisRoot) SupportedUriSchemes() ([]string, error) {
	return []string{}, nil
}

func (r mprisRoot) SupportedMimeTypes() ([]string, error) {
	return []string{}, nil
}

type mprisPlayer struct {
	ctrl *Controller
}

// Implement other methods of `pkg.types.OrgMprisMediaPlayer2PlayerAdapter`.
func (p mprisPlayer) Next() error {
	p.ctrl.Next()

	return nil
}

func (p mprisPlayer) Previous() error {
	p.ctrl.Prev()

	return nil
}

func (p mprisPlayer) Pause() error {
	if p.ctrl.State() == PlaybackStatePlaying {
		p.ctrl.TogglePlayPause()
	}

	return nil
}

func (p mprisPlayer) PlayPause() error {
	switch p.ctrl.State() {
	case PlaybackStatePaused, PlaybackStatePlaying:
		p.ctrl.TogglePlayPause()
	case PlaybackStateStopped:
		p.ctrl.Play(p.ctrl.GetCurrentSong())
	}

	return nil
}

func (p mprisPlayer) Stop() error {
	p.ctrl.Stop()

	return nil
}

func (p mprisPlayer) Play() error {
	switch p.ctrl.State() {
	case PlaybackStatePaused:
		p.ctrl.TogglePlayPause()
	case PlaybackStateStopped:
		p.ctrl.Play(p.ctrl.GetCurrentSong())
	}

	return nil
}

func (p mprisPlayer) Seek(offset mprisTypes.Microseconds) error {
	return nil
}

func (p mprisPlayer) SetPosition(trackId string, position mprisTypes.Microseconds) error {
	return nil
}

func (p mprisPlayer) OpenUri(uri string) error {
	return nil
}

func (p mprisPlayer) PlaybackStatus() (mprisTypes.PlaybackStatus, error) {
	switch p.ctrl.State() {
	case PlaybackStatePlaying:
		return mprisTypes.PlaybackStatusPlaying, nil
	case PlaybackStatePaused:
		return mprisTypes.PlaybackStatusPaused, nil
	case PlaybackStateStopped:
		return mprisTypes.PlaybackStatusStopped, nil
	}
	// Should not get here
	return mprisTypes.PlaybackStatusStopped, nil
}

func (p mprisPlayer) Rate() (float64, error) {
	return 1, nil
}

func (p mprisPlayer) SetRate(float64) error {
	return nil
}

func (p mprisPlayer) Metadata() (mprisTypes.Metadata, error) {
	s := p.ctrl.GetCurrentSong()
	objPath := mprisNoTrack

	if s != nil {
		objPath = encodeTrackID(s.ID)
	} else {
		s = &subsonic.Child{}
	}

	md := mprisTypes.Metadata{
		TrackId:     dbus.ObjectPath(objPath),
		Length:      secondsToMicroseconds(s.Duration),
		Title:       s.Title,
		Album:       s.Album,
		Artist:      []string{s.Artist},
		DiscNumber:  s.DiscNumber,
		Genre:       []string{s.Genre},
		TrackNumber: s.Track,
		UserRating:  float64(s.UserRating),
		UseCount:    int(s.PlayCount),
	}
	artw := client.ArtCache.GetPath(s.CoverArt)

	if artw != nil {
		md.ArtUrl = "file://" + *artw
	}

	return md, nil
}

func (p mprisPlayer) Volume() (float64, error) {
	return 1, nil
}

func (p mprisPlayer) SetVolume(float64) error {
	return nil
}

func (p mprisPlayer) Position() (int64, error) {
	return int64(secondsToMicroseconds(int(p.ctrl.position))), nil
}

func (p mprisPlayer) MinimumRate() (float64, error) {
	return 1, nil
}

func (p mprisPlayer) MaximumRate() (float64, error) {
	return 1, nil
}

func (p mprisPlayer) CanGoNext() (bool, error) {
	return p.ctrl.queue.HasNext(), nil
}

func (p mprisPlayer) CanGoPrevious() (bool, error) {
	return p.ctrl.queue.HasPrev(), nil
}

func (p mprisPlayer) CanPlay() (bool, error) {
	return p.ctrl.GetCurrentSong() != nil, nil
}

func (p mprisPlayer) CanPause() (bool, error) {
	return true, nil
}

func (p mprisPlayer) CanSeek() (bool, error) {
	return false, nil
}

func (p mprisPlayer) CanControl() (bool, error) {
	return true, nil
}

var _ DesktopPlayback = &mprisPlayback{}

type mprisPlayback struct {
	root         mprisRoot
	player       mprisPlayer
	eventHandler *events.EventHandler
	server       *server.Server
	err          error
}

func (p *mprisPlayback) Start() {
	go func() {
		p.err = p.server.Listen()
	}()
}

func (p *mprisPlayback) Stop() error {
	return p.server.Stop()
}

func (p *mprisPlayback) OnPlayPause() {
	if p.err != nil {
		return
	}

	p.err = p.eventHandler.Player.OnPlayPause()
}

func (p *mprisPlayback) OnPlaylistChanged() {
	if p.err != nil {
		return
	}

	p.err = p.eventHandler.Player.OnOptions()
}

func (p *mprisPlayback) OnSongChanged() {
	if p.err != nil {
		return
	}

	p.err = p.eventHandler.Player.OnTitle()
}

func (p *mprisPlayback) OnPositionChanged(position int) {
	if p.err != nil {
		return
	}

	p.err = p.eventHandler.Player.OnSeek(secondsToMicroseconds(position))
	if p.err != nil {
		return
	}

	p.err = p.eventHandler.Player.OnOptions()
}

func desktopPlayer(c *Controller) DesktopPlayback {
	r := mprisRoot{}
	p := mprisPlayer{
		ctrl: c,
	}
	s := server.NewServer(mprisPlayerNmae, r, p)
	ev := events.NewEventHandler(s)

	return &mprisPlayback{
		root:         r,
		player:       p,
		server:       s,
		eventHandler: ev,
	}
}

func secondsToMicroseconds(s int) mprisTypes.Microseconds {
	return mprisTypes.Microseconds(s * 1_000_000)
}

func encodeTrackID(id string) string {
	data := []byte(id)

	return fmt.Sprintf("/%s/Track/%s", mprisPlayerNmae, base32.StdEncoding.WithPadding('0').EncodeToString(data))
}