Initial MPRIS support

Implement a working MPRIS DBus connection with a separate API to control it. Right now only player playback state is reflected and Play/Pause/PlayPause calls work.

src/misc.js

@@ -1,4 +1,4 @@
-const { Gio, Gdk, Gtk } = imports.gi;
+const { Gio, GLib, Gdk, Gtk } = imports.gi;
 const Debug = imports.src.debug;
 
 const { debug } = Debug;
@@ -39,6 +39,57 @@ function getClapperVersion()
         : '';
 }
 
+function getClapperThemeIconUri()
+{
+    const display = Gdk.Display.get_default();
+    if(!display) return null;
+
+    const iconTheme = Gtk.IconTheme.get_for_display(display);
+    if(!iconTheme || !iconTheme.has_icon(appId))
+        return null;
+
+    const iconPaintable = iconTheme.lookup_icon(appId, null, 256, 1,
+        Gtk.TextDirection.NONE, Gtk.IconLookupFlags.FORCE_REGULAR
+    );
+    const iconFile = iconPaintable.get_file();
+    if(!iconFile) return null;
+
+    const iconPath = iconFile.get_path();
+    if(!iconPath) return null;
+
+    let substractName = iconPath.substring(
+        iconPath.indexOf('/icons/') + 7, iconPath.indexOf('/scalable/')
+    );
+    if(!substractName || substractName.includes('/'))
+        return null;
+
+    substractName = substractName.toLowerCase();
+    const postFix = (substractName === iconTheme.theme_name.toLowerCase())
+        ? substractName
+        : 'hicolor';
+    const cacheIconName = `clapper-${postFix}.svg`;
+
+    /* We need to have this icon placed in a folder
+     * accessible from both app runtime and gnome-shell */
+    const expectedFile = Gio.File.new_for_path(
+        GLib.get_user_cache_dir() + `/${appId}/icons/${cacheIconName}`
+    );
+    if(!expectedFile.query_exists(null)) {
+        debug('no cached icon file');
+
+        const dirPath = expectedFile.get_parent().get_path();
+        GLib.mkdir_with_parents(dirPath, 493); // octal 755
+        iconFile.copy(expectedFile,
+            Gio.FileCopyFlags.TARGET_DEFAULT_PERMS, null, null
+        );
+        debug(`icon copied to cache dir: ${cacheIconName}`);
+    }
+    const iconUri = expectedFile.get_uri();
+    debug(`using cached clapper icon uri: ${iconUri}`);
+
+    return iconUri;
+}
+
 function loadCustomCss()
 {
     const clapperPath = getClapperPath();

src/player.js

@@ -20,14 +20,18 @@ class ClapperPlayer extends GstClapper.Clapper
         const glsinkbin = Gst.ElementFactory.make('glsinkbin', null);
         glsinkbin.sink = gtk4plugin.video_sink;
 
-        const dispatcher = new GstClapper.ClapperGMainContextSignalDispatcher();
-        const renderer = new GstClapper.ClapperVideoOverlayVideoRenderer({
-            video_sink: glsinkbin
-        });
-
         super._init({
-            signal_dispatcher: dispatcher,
-            video_renderer: renderer
+            signal_dispatcher: new GstClapper.ClapperGMainContextSignalDispatcher(),
+            video_renderer: new GstClapper.ClapperVideoOverlayVideoRenderer({
+                video_sink: glsinkbin,
+            }),
+            mpris: new GstClapper.ClapperMpris({
+                own_name: `org.mpris.MediaPlayer2.${Misc.appName}`,
+                id_path: '/' + Misc.appId.replace(/\./g, '/'),
+                identity: Misc.appName,
+                desktop_entry: Misc.appId,
+                default_art_url: Misc.getClapperThemeIconUri(),
+            }),
         });
 
         this.widget = gtk4plugin.video_sink.widget;