Throwing an abstraction in front of the player

1 files changed, 299 insertions, 0 deletions

diff --git a/src/media-player-mpris.vala b/src/media-player-mpris.vala
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+++ b/src/media-player-mpris.vala
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+/*
+ * Copyright 2013 Canonical Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 3.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * Authors:
+ *      Lars Uebernickel <lars.uebernickel@canonical.com>
+ */
+
+/**
+ * MediaPlayerMpris represents an MRPIS-capable media player.
+ */
+public class MediaPlayerMpris: MediaPlayer {
+
+	public MediaPlayerMpris (DesktopAppInfo appinfo) {
+		this.appinfo = appinfo;
+	}
+
+	/** Desktop id of the player */
+	public override string id {
+		get {
+			return this.appinfo.get_id ();
+		}
+	}
+
+	/** Display name of the player */
+	public override string name {
+		get {
+			return this.appinfo.get_name ();
+		}
+	}
+
+	/** Application icon of the player */
+	public override Icon? icon {
+		get {
+			return this.appinfo.get_icon ();
+		}
+	}
+
+	/**
+	 * True if an instance of the player is currently running.
+	 *
+	 * See also: attach(), detach()
+	 */
+	public override bool is_running {
+		get {
+			return this.proxy != null;
+		}
+	}
+
+	/** Name of the player on the bus, if an instance is currently running */
+	public override string dbus_name {
+		get {
+			return this._dbus_name;
+		}
+	}
+
+	public override string state {
+		get; private set; default = "Paused";
+	}
+
+	public override MediaPlayer.Track? current_track {
+		get; set;
+	}
+
+	public override bool can_raise {
+		get {
+			return this.root != null ? this.root.CanRaise : true;
+		}
+	}
+
+	/**
+	 * Attach this object to a process of the associated media player.  The player must own @dbus_name and
+	 * implement the org.mpris.MediaPlayer2.Player interface.
+	 *
+	 * Only one player can be attached at any given time.  Use detach() to detach a player.
+	 *
+	 * This method does not block.  If it is successful, "is-running" will be set to %TRUE.
+	 */
+	public void attach (MprisRoot root, string dbus_name) {
+		return_if_fail (this._dbus_name == null && this.proxy == null);
+
+		this.root = root;
+		this.notify_property ("can-raise");
+
+		this._dbus_name = dbus_name;
+		Bus.get_proxy.begin<MprisPlayer> (BusType.SESSION, dbus_name, "/org/mpris/MediaPlayer2",
+										  DBusProxyFlags.GET_INVALIDATED_PROPERTIES, null, got_proxy);
+		Bus.get_proxy.begin<MprisPlaylists> (BusType.SESSION, dbus_name, "/org/mpris/MediaPlayer2",
+											 DBusProxyFlags.GET_INVALIDATED_PROPERTIES, null, got_playlists_proxy);
+	}
+
+	/**
+	 * Detach this object from a process running the associated media player.
+	 *
+	 * See also: attach()
+	 */
+	public void detach () {
+		this.root = null;
+		this.proxy = null;
+		this._dbus_name = null;
+		this.notify_property ("is-running");
+		this.notify_property ("can-raise");
+		this.state = "Paused";
+		this.current_track = null;
+	}
+
+	/**
+	 * Activate the associated media player.
+	 *
+	 * Note: this will _not_ call attach(), because it doesn't know on which dbus-name the player will appear.
+	 * Use attach() to attach this object to a running instance of the player.
+	 */
+	public override void activate () {
+		try {
+			if (this.proxy == null) {
+				this.appinfo.launch (null, null);
+				this.state = "Launching";
+			}
+			else if (this.root != null && this.root.CanRaise) {
+				this.root.Raise ();
+			}
+		}
+		catch (Error e) {
+			warning ("unable to activate %s: %s", appinfo.get_name (), e.message);
+		}
+	}
+
+	/**
+	 * Toggles playing status.
+	 */
+	public override void play_pause () {
+		if (this.proxy != null) {
+			this.proxy.PlayPause.begin ();
+		}
+		else if (this.state != "Launching") {
+			this.play_when_attached = true;
+			this.activate ();
+		}
+	}
+
+	/**
+	 * Skips to the next track.
+	 */
+	public override void next () {
+		if (this.proxy != null)
+			this.proxy.Next.begin ();
+	}
+
+	/**
+	 * Skips to the previous track.
+	 */
+	public override void previous () {
+		if (this.proxy != null)
+			this.proxy.Previous.begin ();
+	}
+
+	public override uint get_n_playlists () {
+		return this.playlists != null ? this.playlists.length : 0;
+	}
+
+	public override string get_playlist_id (int index) {
+		return_val_if_fail (index < this.playlists.length, "");
+		return this.playlists[index].path;
+	}
+
+	public override string get_playlist_name (int index) {
+		return_val_if_fail (index < this.playlists.length, "");
+		return this.playlists[index].name;
+	}
+
+	public override void activate_playlist_by_name (string name) {
+		if (this.playlists_proxy != null)
+			this.playlists_proxy.ActivatePlaylist.begin (new ObjectPath (name));
+	}
+
+	DesktopAppInfo appinfo;
+	MprisPlayer? proxy;
+	MprisPlaylists ?playlists_proxy;
+	string _dbus_name;
+	bool play_when_attached = false;
+	MprisRoot root;
+	PlaylistDetails[] playlists = null;
+
+	void got_proxy (Object? obj, AsyncResult res) {
+		try {
+			this.proxy = Bus.get_proxy.end (res);
+
+			/* Connecting to GDBusProxy's "g-properties-changed" signal here, because vala's dbus objects don't
+			 * emit notify signals */
+			var gproxy = this.proxy as DBusProxy;
+			gproxy.g_properties_changed.connect (this.proxy_properties_changed);
+
+			this.notify_property ("is-running");
+			this.state = this.proxy.PlaybackStatus;
+			this.update_current_track (gproxy.get_cached_property ("Metadata"));
+
+			if (this.play_when_attached) {
+				/* wait a little before calling PlayPause, some players need some time to
+				   set themselves up */
+				Timeout.add (1000, () => { proxy.PlayPause.begin (); return false; } );
+				this.play_when_attached = false;
+			}
+		}
+		catch (Error e) {
+			this._dbus_name = null;
+			warning ("unable to attach to media player: %s", e.message);
+		}
+	}
+
+	void fetch_playlists () {
+		/* The proxy is created even when the interface is not supported. GDBusProxy will
+		   return 0 for the PlaylistCount property in that case. */
+		if (this.playlists_proxy != null && this.playlists_proxy.PlaylistCount > 0) {
+			this.playlists_proxy.GetPlaylists.begin (0, 100, "Alphabetical", false, (obj, res) => {
+				try {
+					this.playlists = playlists_proxy.GetPlaylists.end (res);
+					this.playlists_changed ();
+				}
+				catch (Error e) {
+					warning ("could not fetch playlists: %s", e.message);
+					this.playlists = null;
+				}
+			});
+		}
+		else {
+			this.playlists = null;
+			this.playlists_changed ();
+		}
+	}
+
+	void got_playlists_proxy (Object? obj, AsyncResult res) {
+		try {
+			this.playlists_proxy = Bus.get_proxy.end (res);
+
+			var gproxy = this.proxy as DBusProxy;
+			gproxy.g_properties_changed.connect (this.playlists_proxy_properties_changed);
+		}
+		catch (Error e) {
+			warning ("unable to create mpris plalists proxy: %s", e.message);
+			return;
+		}
+
+		Timeout.add (500, () => { this.fetch_playlists (); return false; } );
+	}
+
+	/* some players (e.g. Spotify) don't follow the spec closely and pass single strings in metadata fields
+	 * where an array of string is expected */
+	static string sanitize_metadata_value (Variant? v) {
+		if (v == null)
+			return "";
+		else if (v.is_of_type (VariantType.STRING))
+			return v.get_string ();
+		else if (v.is_of_type (VariantType.STRING_ARRAY))
+			return string.joinv (",", v.get_strv ());
+
+		warn_if_reached ();
+		return "";
+	}
+
+	void proxy_properties_changed (DBusProxy proxy, Variant changed_properties, string[] invalidated_properties) {
+		if (changed_properties.lookup ("PlaybackStatus", "s", null)) {
+			this.state = this.proxy.PlaybackStatus;
+		}
+
+		var metadata = changed_properties.lookup_value ("Metadata", new VariantType ("a{sv}"));
+		if (metadata != null)
+			this.update_current_track (metadata);
+	}
+
+	void playlists_proxy_properties_changed (DBusProxy proxy, Variant changed_properties, string[] invalidated_properties) {
+		if (changed_properties.lookup ("PlaylistCount", "u", null))
+			this.fetch_playlists ();
+	}
+
+	void update_current_track (Variant metadata) {
+		if (metadata != null) {
+			this.current_track = new Track (
+				sanitize_metadata_value (metadata.lookup_value ("xesam:artist", null)),
+				sanitize_metadata_value (metadata.lookup_value ("xesam:title", null)),
+				sanitize_metadata_value (metadata.lookup_value ("xesam:album", null)),
+				sanitize_metadata_value (metadata.lookup_value ("mpris:artUrl", null))
+			);
+		}
+		else {
+			this.current_track = null;
+		}
+	}
+}