itd/pkg/mpris/mpris.go
razorkitty 1e8c9484d2 copy mpris implementation from infinitime library to itd, where it really belongs
moved dbus.go to an internal utils package
added context function parameter to initMusicCtrl and updated main.go to pass it
updated calls.go, maps.go, music.go, and notifs.go to use utils package for getting a dus connection
2022-11-21 19:59:54 +00:00

273 lines
6.2 KiB
Go

package mpris
import (
"context"
"strings"
"sync"
"github.com/godbus/dbus/v5"
"go.arsenm.dev/itd/internal/utils"
)
var (
method, monitor *dbus.Conn
monitorCh chan *dbus.Message
onChangeOnce sync.Once
)
// Init makes required connections to DBis and
// initializes change monitoring channel
func Init(ctx context.Context) error {
// Connect to session bus for monitoring
monitorConn, err := utils.NewSessionBusConn(ctx)
if err != nil {
return err
}
// Add match rule for PropertiesChanged on media player
monitorConn.AddMatchSignal(
dbus.WithMatchObjectPath("/org/mpris/MediaPlayer2"),
dbus.WithMatchInterface("org.freedesktop.DBus.Properties"),
dbus.WithMatchMember("PropertiesChanged"),
)
monitorCh = make(chan *dbus.Message, 10)
monitorConn.Eavesdrop(monitorCh)
// Connect to session bus for method calls
methodConn, err := utils.NewSessionBusConn(ctx)
if err != nil {
return err
}
method, monitor = methodConn, monitorConn
return nil
}
// Exit closes all connections and channels
func Exit() {
close(monitorCh)
method.Close()
monitor.Close()
}
// Play uses MPRIS to play media
func Play() error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
call := player.Call("org.mpris.MediaPlayer2.Player.Play", 0)
if call.Err != nil {
return call.Err
}
}
return nil
}
// Pause uses MPRIS to pause media
func Pause() error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
call := player.Call("org.mpris.MediaPlayer2.Player.Pause", 0)
if call.Err != nil {
return call.Err
}
}
return nil
}
// Next uses MPRIS to skip to next media
func Next() error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
call := player.Call("org.mpris.MediaPlayer2.Player.Next", 0)
if call.Err != nil {
return call.Err
}
}
return nil
}
// Prev uses MPRIS to skip to previous media
func Prev() error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
call := player.Call("org.mpris.MediaPlayer2.Player.Previous", 0)
if call.Err != nil {
return call.Err
}
}
return nil
}
func VolUp(percent uint) error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
currentVal, err := player.GetProperty("org.mpris.MediaPlayer2.Player.Volume")
if err != nil {
return err
}
newVal := currentVal.Value().(float64) + (float64(percent) / 100)
err = player.SetProperty("org.mpris.MediaPlayer2.Player.Volume", newVal)
if err != nil {
return err
}
}
return nil
}
func VolDown(percent uint) error {
player, err := getPlayerObj()
if err != nil {
return err
}
if player != nil {
currentVal, err := player.GetProperty("org.mpris.MediaPlayer2.Player.Volume")
if err != nil {
return err
}
newVal := currentVal.Value().(float64) - (float64(percent) / 100)
err = player.SetProperty("org.mpris.MediaPlayer2.Player.Volume", newVal)
if err != nil {
return err
}
}
return nil
}
type ChangeType int
const (
ChangeTypeTitle ChangeType = iota
ChangeTypeArtist
ChangeTypeAlbum
ChangeTypeStatus
)
func (ct ChangeType) String() string {
switch ct {
case ChangeTypeTitle:
return "Title"
case ChangeTypeAlbum:
return "Album"
case ChangeTypeArtist:
return "Artist"
case ChangeTypeStatus:
return "Status"
}
return ""
}
// OnChange runs cb when a value changes
func OnChange(cb func(ChangeType, string)) {
go onChangeOnce.Do(func() {
// For every message on channel
for msg := range monitorCh {
// Parse PropertiesChanged
iface, changed, ok := parsePropertiesChanged(msg)
if !ok || iface != "org.mpris.MediaPlayer2.Player" {
continue
}
// For every property changed
for name, val := range changed {
// If metadata changed
if name == "Metadata" {
// Get fields
fields := val.Value().(map[string]dbus.Variant)
// For every field
for name, val := range fields {
// Handle each field appropriately
if strings.HasSuffix(name, "title") {
title := val.Value().(string)
if title == "" {
title = "Unknown " + ChangeTypeTitle.String()
}
cb(ChangeTypeTitle, title)
} else if strings.HasSuffix(name, "album") {
album := val.Value().(string)
if album == "" {
album = "Unknown " + ChangeTypeAlbum.String()
}
cb(ChangeTypeAlbum, album)
} else if strings.HasSuffix(name, "artist") {
var artists string
switch artistVal := val.Value().(type) {
case string:
artists = artistVal
case []string:
artists = strings.Join(artistVal, ", ")
}
if artists == "" {
artists = "Unknown " + ChangeTypeArtist.String()
}
cb(ChangeTypeArtist, artists)
}
}
} else if name == "PlaybackStatus" {
// Handle status change
cb(ChangeTypeStatus, val.Value().(string))
}
}
}
})
}
// getPlayerNames gets all DBus MPRIS player bus names
func getPlayerNames(conn *dbus.Conn) ([]string, error) {
var names []string
err := conn.BusObject().Call("org.freedesktop.DBus.ListNames", 0).Store(&names)
if err != nil {
return nil, err
}
var players []string
for _, name := range names {
if strings.HasPrefix(name, "org.mpris.MediaPlayer2") {
players = append(players, name)
}
}
return players, nil
}
// GetPlayerObj gets the object corresponding to the first
// bus name found in DBus
func getPlayerObj() (dbus.BusObject, error) {
players, err := getPlayerNames(method)
if err != nil {
return nil, err
}
if len(players) == 0 {
return nil, nil
}
return method.Object(players[0], "/org/mpris/MediaPlayer2"), nil
}
// parsePropertiesChanged parses a DBus PropertiesChanged signal
func parsePropertiesChanged(msg *dbus.Message) (iface string, changed map[string]dbus.Variant, ok bool) {
if len(msg.Body) != 3 {
return "", nil, false
}
iface, ok = msg.Body[0].(string)
if !ok {
return
}
changed, ok = msg.Body[1].(map[string]dbus.Variant)
if !ok {
return
}
return
}