service/mpris: add properties for common track metadata

This was done to work around bad player implementations sending weird
metadata, such as removing the art url halfway through a song.

src/services/mpris/player.cpp

@@ -1,4 +1,5 @@
 #include "player.hpp"
+#include <utility>
 
 #include <qcontainerfwd.h>
 #include <qdatetime.h>
@@ -255,6 +256,11 @@ void MprisPlayer::setVolume(qreal volume) {
 }
 
 QVariantMap MprisPlayer::metadata() const { return this->pMetadata.get(); }
+QString MprisPlayer::trackTitle() const { return this->mTrackTitle; }
+QString MprisPlayer::trackAlbum() const { return this->mTrackAlbum; }
+QString MprisPlayer::trackAlbumArtist() const { return this->mTrackAlbumArtist; }
+QVector<QString> MprisPlayer::trackArtists() const { return this->mTrackArtists; }
+QString MprisPlayer::trackArtUrl() const { return this->mTrackArtUrl; }
 
 void MprisPlayer::onMetadataChanged() {
 	emit this->metadataChanged();
@@ -274,7 +280,7 @@ void MprisPlayer::onMetadataChanged() {
 
 	auto trackidVariant = this->pMetadata.get().value("mpris:trackid");
 	if (trackidVariant.isValid() && trackidVariant.canConvert<QString>()) {
-		auto trackId = trackidVariant.value<QString>();
+		auto trackId = trackidVariant.toString();
 
 		if (trackId != this->mTrackId) {
 			this->mTrackId = trackId;
@@ -285,14 +291,49 @@ void MprisPlayer::onMetadataChanged() {
 	// Helps to catch players without trackid.
 	auto urlVariant = this->pMetadata.get().value("xesam:url");
 	if (urlVariant.isValid() && urlVariant.canConvert<QString>()) {
-		auto url = urlVariant.value<QString>();
+		auto url = urlVariant.toString();
 
-		if (url != this->mUrl) {
+		if (url != this->mTrackUrl) {
-			this->mUrl = url;
+			this->mTrackUrl = url;
 			trackChanged = true;
 		}
 	}
 
+	auto trackTitle = this->pMetadata.get().value("xesam:title");
+	if (trackTitle.isValid() && trackTitle.canConvert<QString>()) {
+		this->setTrackTitle(trackTitle.toString());
+	} else if (trackChanged) {
+		this->setTrackTitle("Unknown Track");
+	}
+
+	auto trackAlbum = this->pMetadata.get().value("xesam:album");
+	if (trackAlbum.isValid() && trackAlbum.canConvert<QString>()) {
+		this->setTrackAlbum(trackAlbum.toString());
+	} else if (trackChanged) {
+		this->setTrackAlbum("Unknown Album");
+	}
+
+	auto trackAlbumArtist = this->pMetadata.get().value("xesam:albumArtist");
+	if (trackAlbumArtist.isValid() && trackAlbumArtist.canConvert<QString>()) {
+		this->setTrackAlbumArtist(trackAlbumArtist.toString());
+	} else if (trackChanged) {
+		this->setTrackAlbumArtist("Unknown Artist");
+	}
+
+	auto trackArtists = this->pMetadata.get().value("xesam:artist");
+	if (trackArtists.isValid() && trackArtists.canConvert<QVector<QString>>()) {
+		this->setTrackArtists(trackArtists.value<QVector<QString>>());
+	} else if (trackChanged) {
+		this->setTrackArtists({});
+	}
+
+	auto trackArtUrl = this->pMetadata.get().value("mpris:artUrl");
+	if (trackArtUrl.isValid() && trackArtUrl.canConvert<QString>()) {
+		this->setTrackArtUrl(trackArtUrl.toString());
+	} else if (trackChanged) {
+		this->setTrackArtUrl("");
+	}
+
 	if (trackChanged) {
 		// Some players don't seem to send position updates or seeks on track change.
 		this->pPosition.update();
@@ -300,6 +341,41 @@ void MprisPlayer::onMetadataChanged() {
 	}
 }
 
+void MprisPlayer::setTrackTitle(QString title) {
+	if (title == this->mTrackTitle) return;
+
+	this->mTrackTitle = std::move(title);
+	emit this->trackTitleChanged();
+}
+
+void MprisPlayer::setTrackAlbum(QString album) {
+	if (album == this->mTrackAlbum) return;
+
+	this->mTrackAlbum = std::move(album);
+	emit this->trackAlbumChanged();
+}
+
+void MprisPlayer::setTrackAlbumArtist(QString albumArtist) {
+	if (albumArtist == this->mTrackAlbumArtist) return;
+
+	this->mTrackAlbumArtist = std::move(albumArtist);
+	emit this->trackAlbumArtistChanged();
+}
+
+void MprisPlayer::setTrackArtists(QVector<QString> artists) {
+	if (artists == this->mTrackArtists) return;
+
+	this->mTrackArtists = std::move(artists);
+	emit this->trackArtistsChanged();
+}
+
+void MprisPlayer::setTrackArtUrl(QString artUrl) {
+	if (artUrl == this->mTrackArtUrl) return;
+
+	this->mTrackArtUrl = std::move(artUrl);
+	emit this->trackArtUrlChanged();
+}
+
 MprisPlaybackState::Enum MprisPlayer::playbackState() const { return this->mPlaybackState; }
 
 void MprisPlayer::setPlaybackState(MprisPlaybackState::Enum playbackState) {

src/services/mpris/player.hpp

@@ -122,7 +122,21 @@ class MprisPlayer: public QObject {
 	///
 	/// A map of common properties is available [here](https://www.freedesktop.org/wiki/Specifications/mpris-spec/metadata).
 	/// Do not count on any of them actually being present.
+	///
+	/// Note that the `trackTitle`, `trackAlbum`, `trackAlbumArtist`, `trackArtists` and `trackArtUrl`
+	/// properties have extra logic to guard against bad players sending weird metadata, and should
+	/// be used over grabbing the properties directly from the metadata.
 	Q_PROPERTY(QVariantMap metadata READ metadata NOTIFY metadataChanged);
+	/// The title of the current track, or "Unknown Track" if none was provided.
+	Q_PROPERTY(QString trackTitle READ trackTitle NOTIFY trackTitleChanged);
+	/// The current track's album, or "Unknown Album" if none was provided.
+	Q_PROPERTY(QString trackAlbum READ trackAlbum NOTIFY trackAlbumChanged);
+	/// The current track's album artist, or "Unknown Artist" if none was provided.
+	Q_PROPERTY(QString trackAlbumArtist READ trackAlbumArtist NOTIFY trackAlbumArtistChanged);
+	/// The current track's artists, or an empty list if none were provided.
+	Q_PROPERTY(QVector<QString> trackArtists READ trackArtists NOTIFY trackArtistsChanged);
+	/// The current track's art url, or `""` if none was provided.
+	Q_PROPERTY(QString trackArtUrl READ trackArtUrl NOTIFY trackArtUrlChanged);
 	/// The playback state of the media player.
 	///
 	/// - If `canPlay` is false, you cannot assign the `Playing` state.
@@ -234,6 +248,11 @@ public:
 	void setVolume(qreal volume);
 
 	[[nodiscard]] QVariantMap metadata() const;
+	[[nodiscard]] QString trackTitle() const;
+	[[nodiscard]] QString trackAlbum() const;
+	[[nodiscard]] QString trackAlbumArtist() const;
+	[[nodiscard]] QVector<QString> trackArtists() const;
+	[[nodiscard]] QString trackArtUrl() const;
 
 	[[nodiscard]] MprisPlaybackState::Enum playbackState() const;
 	void setPlaybackState(MprisPlaybackState::Enum playbackState);
@@ -280,6 +299,11 @@ signals:
 	void volumeChanged();
 	void volumeSupportedChanged();
 	void metadataChanged();
+	void trackTitleChanged();
+	void trackAlbumChanged();
+	void trackAlbumArtistChanged();
+	void trackArtistsChanged();
+	void trackArtUrlChanged();
 	void playbackStateChanged();
 	void loopStateChanged();
 	void loopSupportedChanged();
@@ -302,6 +326,12 @@ private slots:
 	void onLoopStatusChanged();
 
 private:
+	void setTrackTitle(QString title);
+	void setTrackAlbum(QString album);
+	void setTrackAlbumArtist(QString albumArtist);
+	void setTrackArtists(QVector<QString> artists);
+	void setTrackArtUrl(QString artUrl);
+
 	// clang-format off
 	dbus::DBusPropertyGroup appProperties;
 	dbus::DBusProperty<QString> pIdentity {this->appProperties, "Identity"};
@@ -340,7 +370,12 @@ private:
 	DBusMprisPlayerApp* app = nullptr;
 	DBusMprisPlayer* player = nullptr;
 	QString mTrackId;
-	QString mUrl;
+	QString mTrackUrl;
+	QString mTrackTitle;
+	QString mTrackAlbum;
+	QString mTrackAlbumArtist;
+	QVector<QString> mTrackArtists;
+	QString mTrackArtUrl;
 };
 
 } // namespace qs::service::mpris