service/mpris: hack around more non-compliant players

Mpris is currently winning the competition for least compliant clients.

Author: outfoxxed

src/services/mpris/player.cpp

@@ -1,5 +1,6 @@
 #include "player.hpp"
 
+#include <qtimer.h>
 #include <qcontainerfwd.h>
 #include <qdatetime.h>
 #include <qdbusconnection.h>
@@ -317,11 +318,24 @@ void MprisPlayer::onMetadataChanged() {
 		}
 	}
 
+	// Some players (Jellyfin) specify xesam:url or mpris:trackid
+	// and DON'T ACTUALLY CHANGE THEM WHEN THE TRACK CHANGES.
+	auto titleVariant = this->bpMetadata.value().value("xesam:title");
+	if (titleVariant.isValid() && titleVariant.canConvert<QString>()) {
+		auto title = titleVariant.toString();
+
+		if (title != this->mTrackTitle) {
+			this->mTrackTitle = title;
+			trackChanged = true;
+		}
+	}
+
 	Qt::beginPropertyUpdateGroup();
 
 	if (trackChanged) {
 		emit this->trackChanged();
 		this->bUniqueId = this->bUniqueId + 1;
+		this->trackChangedBeforeState = true;
 
 		// Some players don't seem to send position updates or seeks on track change.
 		this->pPosition.requestUpdate();
@@ -386,6 +400,23 @@ void MprisPlayer::setPlaying(bool playing) {
 	this->togglePlaying();
 }
 
+void MprisPlayer::onPlaybackStatusUpdated() {
+	// Insurance - have not yet seen a player where this particular check is required that doesn't
+	// require the late query below.
+	this->pPosition.requestUpdate();
+
+	// For exceptionally bad players that update playback timestamps at an indeterminate time AFTER
+	// updating playback state. (Youtube)
+	QTimer::singleShot(100, this, [&]() { this->pPosition.requestUpdate(); });
+
+	// For exceptionally bad players that don't update length (or other metadata) until a new track actually
+	// starts playing, and then don't trigger a metadata update when they do. (Jellyfin)
+	if (this->trackChangedBeforeState) {
+		this->trackChangedBeforeState = false;
+		this->pMetadata.requestUpdate();
+	}
+}
+
 bool MprisPlayer::loopSupported() const { return this->pLoopStatus.exists(); }
 
 void MprisPlayer::setLoopState(MprisLoopState::Enum loopState) {

src/services/mpris/player.hpp

@@ -242,7 +242,7 @@ class MprisPlayer: public QObject {
 	/// Equivalent to calling @@play() if not playing or @@pause() if playing.
 	///
 	/// May only be called if @@canTogglePlaying is true, which is equivalent to
-	/// @@canPlay or @@canPause() depending on the current playback state.
+	/// @@canPlay or @@canPause depending on the current playback state.
 	Q_INVOKABLE void togglePlaying();
 
 	[[nodiscard]] bool isValid() const;
@@ -391,6 +391,7 @@ private slots:
 private:
 	void onMetadataChanged();
 	void onPositionUpdated();
+	void onPlaybackStatusUpdated();
 	// call instead of setting bpPosition
 	void setPosition(qlonglong position);
 	void requestPositionUpdate() { this->pPosition.requestUpdate(); };
@@ -462,7 +463,7 @@ private slots:
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, qlonglong, pPosition, bpPosition, onPositionUpdated, playerProperties, "Position", false);
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pVolume, bVolume, playerProperties, "Volume", false);
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pMetadata, bpMetadata, playerProperties, "Metadata");
-	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pPlaybackStatus, bpPlaybackStatus, playerProperties, "PlaybackStatus");
+	QS_DBUS_PROPERTY_BINDING(MprisPlayer, void, pPlaybackStatus, bpPlaybackStatus, onPlaybackStatusUpdated, playerProperties, "PlaybackStatus", true);
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pLoopStatus, bpLoopStatus, playerProperties, "LoopStatus", false);
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pRate, bRate, playerProperties, "Rate", false);
 	QS_DBUS_PROPERTY_BINDING(MprisPlayer, pMinRate, bMinRate, playerProperties, "MinimumRate", false);
@@ -477,6 +478,8 @@ private slots:
 	DBusMprisPlayer* player = nullptr;
 	QString mTrackId;
 	QString mTrackUrl;
+	QString mTrackTitle;
+	bool trackChangedBeforeState = false;
 };
 
 } // namespace qs::service::mpris