Add toggle play button to remote app

A single toggle play button for now. Meant for testing the remote communication/delays over local network.

clapper_src/widgetRemote.js

@@ -1,4 +1,5 @@
-const { GObject, Gtk } = imports.gi;
+const { GObject, Gtk, GstPlayer } = imports.gi;
+const Buttons = imports.clapper_src.buttons;
 const Misc = imports.clapper_src.misc;
 const { PlayerRemote } = imports.clapper_src.playerRemote;
 
@@ -7,17 +8,59 @@ class ClapperWidgetRemote extends Gtk.Grid
 {
     _init(opts)
     {
-        super._init();
+        super._init({
+            halign: Gtk.Align.CENTER,
+            valign: Gtk.Align.CENTER,
+        });
 
         Misc.loadCustomCss();
 
         this.player = new PlayerRemote();
         this.player.webclient.passMsgData = this.receiveWs.bind(this);
+
+        /* FIXME: create better way to add buttons for
+         * remote app without duplicating too much code */
+        this.togglePlayButton = new Buttons.IconToggleButton(
+            'media-playback-start-symbolic',
+            'media-playback-pause-symbolic'
+        );
+        this.togglePlayButton.remove_css_class('flat');
+        this.togglePlayButton.child.add_css_class('playbackicon');
+        this.togglePlayButton.connect(
+            'clicked', this.sendWs.bind(this, 'toggle_play')
+        );
+
+        this.attach(this.togglePlayButton, 0, 0, 1, 1);
+    }
+
+    sendWs(action, value)
+    {
+        const data = { action };
+
+        /* do not send "null" or "undefined"
+         * for faster network data transfer */
+        if(value != null)
+            data.value = value;
+
+        this.player.webclient.sendMessage(data);
     }
 
     receiveWs(action, value)
     {
         switch(action) {
+            case 'state_changed':
+                switch(value) {
+                    case GstPlayer.PlayerState.STOPPED:
+                    case GstPlayer.PlayerState.PAUSED:
+                        this.togglePlayButton.setPrimaryIcon();
+                        break;
+                    case GstPlayer.PlayerState.PLAYING:
+                        this.togglePlayButton.setSecondaryIcon();
+                        break;
+                    default:
+                        break;
+                }
+                break;
             case 'close':
                 let root = this.get_root();
                 root.run_dispose();