softdsp-endpoint: automatically deselect other endpoints when one is selected

Only one endpoint of a certain media class can be selected at a time

modules/module-pw-audio-softdsp-endpoint.c

@@ -619,9 +619,50 @@ endpoint_factory (WpFactory * factory, GType type, GVariant * properties)
   return ep;
 }
 
+static void
+global_endpoint_notify_control_value (WpEndpoint * ep, guint control_id,
+    WpCore * core)
+{
+  WpPwAudioSoftdspEndpoint *sdspep = WP_PW_AUDIO_SOFTDSP_ENDPOINT (ep);
+  g_autoptr (GPtrArray) a = NULL;
+  int i;
+
+  /* when an endpoint becomes "selected", unselect
+   * all other endpoints of the same media class */
+  if (control_id == CONTROL_SELECTED && sdspep->selected) {
+    g_debug ("selected: %p", ep);
+    a = wp_endpoint_find (core, wp_endpoint_get_media_class (ep));
+
+    for (i = 0; i < a->len; i++) {
+      WpEndpoint *other = g_ptr_array_index (a, i);
+      if (!WP_PW_IS_AUDIO_SOFTDSP_ENDPOINT (ep)
+          || other == ep
+          || !WP_PW_AUDIO_SOFTDSP_ENDPOINT (other)->selected)
+        continue;
+
+      g_debug ("unselecting %p", other);
+      WP_PW_AUDIO_SOFTDSP_ENDPOINT (other)->selected = FALSE;
+      wp_endpoint_notify_control_value (other, CONTROL_SELECTED);
+    }
+  }
+}
+
+static void
+global_endpoint_added (WpCore *core, GQuark key, WpEndpoint *ep, gpointer data)
+{
+  if (WP_PW_IS_AUDIO_SOFTDSP_ENDPOINT (ep)) {
+    g_debug ("connecting to notify-control-value for %p", ep);
+    g_signal_connect (ep, "notify-control-value",
+        (GCallback) global_endpoint_notify_control_value, core);
+  }
+}
+
 void
 wireplumber__module_init (WpModule * module, WpCore * core, GVariant * args)
 {
   /* Register the softdsp endpoint */
   wp_factory_new (core, "pw-audio-softdsp-endpoint", endpoint_factory);
+
+  g_signal_connect (core, "global-added::endpoint",
+      (GCallback) global_endpoint_added, NULL);
 }