Implement GNOME Settings Daemon MediaKeys handling.

Clean up some warnings.

src/koto-playerbar.c

@@ -88,10 +88,6 @@ static void koto_playerbar_constructed(GObject *obj) {
 	gtk_range_set_increments(GTK_RANGE(self->progress_bar), 1, 1);
 	gtk_range_set_round_digits(GTK_RANGE(self->progress_bar), 1);
 
-	GtkEventController *scroll_controller = gtk_event_controller_scroll_new(GTK_EVENT_CONTROLLER_SCROLL_HORIZONTAL);
-	g_signal_connect(scroll_controller, "scroll-begin", G_CALLBACK(koto_playerbar_handle_progressbar_scroll_begin), self);
-	gtk_widget_add_controller(GTK_WIDGET(self->progress_bar), scroll_controller);
-
 	GtkGesture *press_controller = gtk_gesture_click_new(); // Create a new GtkGestureLongPress
 	gtk_gesture_single_set_button(GTK_GESTURE_SINGLE(press_controller), 1); // Set to left click
 
@@ -241,7 +237,6 @@ void koto_playerbar_create_secondary_controls(KotoPlayerBar* bar) {
 	if (GTK_IS_VOLUME_BUTTON(bar->volume_button)) {
 		GtkAdjustment *granular_volume_change = gtk_adjustment_new(0.5, 0, 1.0, 0.02, 0.02, 0.02);
 		g_object_set(bar->volume_button, "use-symbolic", TRUE, NULL);
-		gtk_range_set_round_digits(GTK_RANGE(bar->volume_button), FALSE);
 		gtk_scale_button_set_adjustment(GTK_SCALE_BUTTON(bar->volume_button), granular_volume_change); // Set our adjustment
 		gtk_box_append(GTK_BOX(bar->secondary_controls_section), bar->volume_button);
 
@@ -290,10 +285,6 @@ void koto_playerbar_handle_is_paused(KotoPlaybackEngine *engine, gpointer user_d
 	koto_button_show_image(bar->play_pause_button, FALSE); // Set to FALSE to show play as the next action
 }
 
-void koto_playerbar_handle_progressbar_scroll_begin(GtkEventControllerScroll *controller, gpointer data){
-	(void) controller;
-}
-
 void koto_playerbar_handle_progressbar_gesture_begin(GtkGesture *gesture, GdkEventSequence *seq, gpointer data) {
 	(void) gesture; (void) seq;
 	KotoPlayerBar *bar = data;

src/main.c

@@ -19,6 +19,7 @@
 #include <gstreamer-1.0/gst/gst.h>
 #include "db/cartographer.h"
 #include "db/db.h"
+#include "playback/media-keys.h"
 #include "playback/mimes.h"
 #include "playback/mpris.h"
 
@@ -43,6 +44,8 @@ static void on_activate (GtkApplication *app) {
 	main_window = gtk_application_get_active_window (app);
 	if (main_window == NULL) {
 		main_window = g_object_new(KOTO_TYPE_WINDOW,  "application", app,  "default-width", 1200,  "default-height", 675, NULL);
+		setup_mpris_interfaces(); // Set up our MPRIS interfaces
+		setup_mediakeys_interface(); // Set up our media key support
 	}
 
 	gtk_window_present(main_window);
@@ -72,7 +75,6 @@ int main (int argc, char *argv[]) {
 
 	koto_maps = koto_cartographer_new(); // Create our new cartographer and their collection of maps
 	open_db(); // Open our database
-	setup_mpris_interfaces(); // Set up our MPRIS interfaces
 
 	app = gtk_application_new ("com.github.joshstrobl.koto", G_APPLICATION_FLAGS_NONE);
 	g_signal_connect (app, "activate", G_CALLBACK (on_activate), NULL);

src/meson.build

@@ -12,6 +12,7 @@ koto_sources = [
 	'pages/music/disc-view.c',
 	'pages/music/music-local.c',
 	'playback/engine.c',
+	'playback/media-keys.c',
 	'playback/mimes.c',
 	'playback/mpris.c',
 	'playlist/current.c',

src/playback/media-keys.c

@@ -0,0 +1,174 @@
+/* media-keys.c
+ *
+ * Copyright 2021 Joshua Strobl
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * 	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <glib-2.0/glib.h>
+#include <glib-2.0/gio/gio.h>
+#include <gtk-4.0/gtk/gtk.h>
+#include "engine.h"
+#include "media-keys.h"
+
+extern GtkWindow *main_window;
+extern KotoPlaybackEngine *playback_engine;
+
+GDBusConnection *media_keys_dbus_conn = NULL;
+GDBusProxy *media_keys_proxy = NULL;
+GDBusNodeInfo *media_keys_introspection_data = NULL;
+
+static const gchar introspection_xml[] =
+"<node name='/org/gnome/SettingsDaemon/MediaKeys'>"
+"  <interface name='org.gnome.SettingsDaemon.MediaKeys'>"
+"    <annotation name='org.freedesktop.DBus.GLib.CSymbol' value='gsd_media_keys_manager'/>"
+"    <method name='GrabMediaPlayerKeys'>"
+"      <arg name='application' direction='in' type='s'/>"
+"      <arg name='time' direction='in' type='u'/>"
+"    </method>"
+"    <method name='ReleaseMediaPlayerKeys'>"
+"      <arg name='application' direction='in' type='s'/>"
+"    </method>"
+"    <signal name='MediaPlayerKeyPressed'>"
+"      <arg name='application' type='s'/>"
+"      <arg name='key' type='s'/>"
+"    </signal>"
+"  </interface>"
+"</node>";
+
+void grab_media_keys() {
+	if (media_keys_proxy == NULL) { // No connection
+		return;
+	}
+
+	g_dbus_proxy_call(
+		media_keys_proxy,
+		"GrabMediaPlayerKeys",
+		g_variant_new("(su)", "com.github.joshstrobl.koto", 0),
+		G_DBUS_CALL_FLAGS_NONE,
+		-1,
+		NULL,
+		handle_media_keys_async_done,
+		NULL
+	);
+}
+
+void handle_media_keys_async_done(GObject *source_object, GAsyncResult *res, gpointer user_data) {
+	(void) user_data;
+	g_dbus_proxy_call_finish(G_DBUS_PROXY(source_object), res, NULL); // Ensure we finish our call
+}
+
+void handle_media_keys_signal(GDBusProxy *proxy, const gchar *sender_name, const gchar *signal_name, GVariant *parameters, gpointer user_data) {
+	(void) proxy; (void) sender_name; (void) user_data;
+	if (g_strcmp0(signal_name, "MediaPlayerKeyPressed") != 0) { // Not MediaPlayerKeyPressed
+		return;
+	}
+
+	gchar *application_name = NULL;
+	gchar *key = NULL;
+
+	g_variant_get(parameters, "(ss)", &application_name, &key);
+
+	if (g_strcmp0(application_name, "com.github.joshstrobl.koto") != 0) { // Not for Koto
+		return;
+	}
+
+	if (g_strcmp0(key, "Play") == 0) {
+		koto_playback_engine_play(playback_engine);
+	} else if (g_strcmp0(key, "Pause") == 0) {
+		koto_playback_engine_pause(playback_engine);
+	} else if (g_strcmp0(key, "Stop") == 0) {
+		koto_playback_engine_stop(playback_engine);
+	} else if (g_strcmp0(key, "Previous") == 0) {
+		koto_playback_engine_backwards(playback_engine);
+	} else if (g_strcmp0(key, "Next") == 0) {
+		koto_playback_engine_forwards(playback_engine);
+	} else if (g_strcmp0(key, "Repeat") == 0) {
+		koto_playback_engine_toggle_track_repeat(playback_engine);
+	} else if (g_strcmp0(key, "Shuffle") == 0) {
+		koto_playback_engine_toggle_track_shuffle(playback_engine);
+	}
+}
+
+void handle_window_enter(GtkEventControllerFocus *controller, gpointer user_data) {
+	grab_media_keys(); // Grab our media keys
+}
+
+void handle_window_leave(GtkEventControllerFocus *controller, gpointer user_data) {
+	release_media_keys(); // Release our media keys
+}
+
+void release_media_keys() {
+	if (media_keys_dbus_conn == NULL) { // No connection
+		return;
+	}
+
+	GVariant *params = g_variant_new_string(g_strdup("com.github.joshstrobl.koto"));
+
+	g_dbus_proxy_call(
+		media_keys_proxy,
+		"ReleaseMediaPlayerKeys",
+		params,
+		G_DBUS_CALL_FLAGS_NONE,
+		-1,
+		NULL,
+		handle_media_keys_async_done,
+		NULL
+	);
+}
+
+void setup_mediakeys_interface() {
+	media_keys_introspection_data = g_dbus_node_info_new_for_xml(introspection_xml, NULL);
+	g_assert(media_keys_introspection_data != NULL);
+
+	GDBusConnection *bus;
+	GError *error = NULL;
+
+	bus = g_bus_get_sync(G_BUS_TYPE_SESSION, NULL, &error);
+
+	if (bus == NULL) { // Failed to get session bus
+		g_printerr("Failed to get our session bus: %s\n", error->message);
+		g_error_free(error);
+		return;
+	}
+
+	media_keys_proxy = g_dbus_proxy_new_sync(
+		bus,
+		G_DBUS_PROXY_FLAGS_NONE,
+		NULL,
+		"org.gnome.SettingsDaemon.MediaKeys",
+		"/org/gnome/SettingsDaemon/MediaKeys",
+		"org.gnome.SettingsDaemon.MediaKeys",
+		NULL,
+		&error
+	);
+
+	if (media_keys_proxy == NULL) {
+		g_printerr("Failed to get a proxy to GNOME Settings Daemon Media-Keys: %s\n", error->message);
+		g_error_free(error);
+		return;
+	}
+
+	g_signal_connect_object(
+		media_keys_proxy,
+		"g-signal",
+		G_CALLBACK(handle_media_keys_signal),
+		NULL,
+		0
+	);
+
+	GtkEventController *focus_controller = gtk_event_controller_focus_new(); // Create a new focus controller
+	g_signal_connect(focus_controller, "enter", G_CALLBACK(handle_window_enter), NULL);
+	g_signal_connect(focus_controller, "leave", G_CALLBACK(handle_window_leave), NULL);
+	gtk_widget_add_controller(GTK_WIDGET(main_window), focus_controller);
+}

src/playback/media-keys.h

@@ -0,0 +1,32 @@
+/* media-keys.h
+ *
+ * Copyright 2021 Joshua Strobl
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * 	http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <glib-2.0/glib.h>
+#include <glib-2.0/gio/gio.h>
+#include <gtk-4.0/gtk/gtk.h>
+
+G_BEGIN_DECLS
+
+void grab_media_keys();
+void handle_media_keys_async_done(GObject *source_object, GAsyncResult *res, gpointer user_data);
+void handle_media_keys_signal(GDBusProxy *proxy, const gchar *sender_name, const gchar *signal_name, GVariant *parameters, gpointer user_data);
+void handle_window_enter(GtkEventControllerFocus *controller, gpointer user_data);
+void handle_window_leave(GtkEventControllerFocus *controller, gpointer user_data);
+void release_media_keys();
+void setup_mediakeys_interface();
+
+G_END_DECLS