application: Integrate with Night Light

This is mostly a nice touch of integration for when
using the Night Light feature. It can be disabled by
switching the 'follow-night-light' dconf key to false,
but no user interface widgetry was added.

src/gcal-application.c

@@ -26,6 +26,7 @@
 #include "gcal-debug.h"
 #include "gcal-enums.h"
 #include "gcal-log.h"
+#include "gcal-night-light-monitor.h"
 #include "gcal-shell-search-provider.h"
 #include "gcal-weather-service.h"
 #include "gcal-window.h"
@@ -53,8 +54,8 @@ struct _GcalApplication
   GcalTimeFormat      time_format;
 
   GcalWeatherService *weather_service;
-
   GcalShellSearchProvider *search_provider;
+  GcalNightLightMonitor *night_light_monitor;
 
   GcalClock          *clock;
 };
@@ -230,6 +231,7 @@ gcal_application_finalize (GObject *object)
   g_clear_object (&self->clock);
   g_clear_object (&self->desktop_settings);
   g_clear_object (&self->manager);
+  g_clear_object (&self->night_light_monitor);
   g_clear_object (&self->provider);
   g_clear_object (&self->search_provider);
   g_clear_object (&self->weather_service);
@@ -293,6 +295,9 @@ gcal_application_activate (GApplication *application)
                                                  GTK_STYLE_PROVIDER_PRIORITY_APPLICATION + 2);
     }
 
+  if (!self->night_light_monitor)
+    self->night_light_monitor = gcal_night_light_monitor_new (self->manager);
+
   if (!self->window)
     {
       if (!self->initial_date)

src/gcal-night-light-monitor.c

@@ -0,0 +1,206 @@
+/* gcal-night-light-monitor.c
+ *
+ * Copyright 2018 Georges Basile Stavracas Neto <georges.stavracas@gmail.com>
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#include "gcal-debug.h"
+#include "gcal-night-light-monitor.h"
+
+struct _GcalNightLightMonitor
+{
+  GObject             parent;
+
+  GcalManager        *manager;
+
+  GDBusProxy         *night_light_proxy;
+};
+
+G_DEFINE_TYPE (GcalNightLightMonitor, gcal_night_light_monitor, G_TYPE_OBJECT)
+
+enum
+{
+  PROP_0,
+  PROP_MANAGER,
+  N_PROPS
+};
+
+static GParamSpec *properties [N_PROPS];
+
+
+/*
+ * Callbacks
+ */
+
+static void
+on_night_light_proxy_properties_changed_cb (GcalNightLightMonitor *self,
+                                            GVariant              *properties,
+                                            const gchar * const   *invalidated,
+                                            GDBusProxy            *proxy)
+{
+  GSettings *settings;
+
+  g_assert (GCAL_IS_NIGHT_LIGHT_MONITOR (self));
+  g_assert (G_IS_DBUS_PROXY (proxy));
+
+  settings = gcal_manager_get_settings (self->manager);
+
+  if (g_settings_get_boolean (settings, "follow-night-light"))
+    {
+      g_autoptr (GVariant) activev = NULL;
+      gboolean active;
+
+      activev = g_dbus_proxy_get_cached_property (proxy, "NightLightActive");
+      active = g_variant_get_boolean (activev);
+
+      g_object_set (gtk_settings_get_default (),
+                    "gtk-application-prefer-dark-theme",
+                    active,
+                    NULL);
+    }
+}
+
+
+/*
+ * GObject overrides
+ */
+
+static void
+gcal_night_light_monitor_finalize (GObject *object)
+{
+  GcalNightLightMonitor *self = (GcalNightLightMonitor *)object;
+
+  g_clear_object (&self->manager);
+  g_clear_object (&self->night_light_proxy);
+
+  G_OBJECT_CLASS (gcal_night_light_monitor_parent_class)->finalize (object);
+}
+
+static void
+gcal_night_light_monitor_constructed (GObject *object)
+{
+  GcalNightLightMonitor *self = (GcalNightLightMonitor *)object;
+  g_autoptr (GDBusConnection) connection = NULL;
+  g_autoptr (GDBusProxy) proxy = NULL;
+
+  GCAL_ENTRY;
+
+  G_OBJECT_CLASS (gcal_night_light_monitor_parent_class)->constructed (object);
+
+  connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, NULL);
+
+  if (!connection)
+    GCAL_RETURN ();
+
+  proxy = g_dbus_proxy_new_sync (connection,
+                                 G_DBUS_PROXY_FLAGS_GET_INVALIDATED_PROPERTIES,
+                                 NULL,
+                                 "org.gnome.SettingsDaemon.Color",
+                                 "/org/gnome/SettingsDaemon/Color",
+                                 "org.gnome.SettingsDaemon.Color",
+                                 NULL,
+                                 NULL);
+
+  if (!proxy)
+    GCAL_RETURN ();
+
+  g_debug ("Created Night Light monitor");
+
+  g_signal_connect_object (proxy,
+                           "g-properties-changed",
+                           G_CALLBACK (on_night_light_proxy_properties_changed_cb),
+                           self,
+                           G_CONNECT_SWAPPED);
+
+  self->night_light_proxy = g_steal_pointer (&proxy);
+
+  on_night_light_proxy_properties_changed_cb (self, NULL, NULL, self->night_light_proxy);
+
+  GCAL_EXIT;
+}
+
+static void
+gcal_night_light_monitor_get_property (GObject    *object,
+                                       guint       prop_id,
+                                       GValue     *value,
+                                       GParamSpec *pspec)
+{
+  GcalNightLightMonitor *self = GCAL_NIGHT_LIGHT_MONITOR (object);
+
+  switch (prop_id)
+    {
+    case PROP_MANAGER:
+      g_value_set_object (value, self->manager);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+gcal_night_light_monitor_set_property (GObject      *object,
+                                       guint         prop_id,
+                                       const GValue *value,
+                                       GParamSpec   *pspec)
+{
+  GcalNightLightMonitor *self = GCAL_NIGHT_LIGHT_MONITOR (object);
+
+  switch (prop_id)
+    {
+    case PROP_MANAGER:
+      g_assert (self->manager == NULL);
+      self->manager = g_value_dup_object (value);
+      g_object_notify_by_pspec (object, pspec);
+      break;
+
+    default:
+      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
+    }
+}
+
+static void
+gcal_night_light_monitor_class_init (GcalNightLightMonitorClass *klass)
+{
+  GObjectClass *object_class = G_OBJECT_CLASS (klass);
+
+  object_class->finalize = gcal_night_light_monitor_finalize;
+  object_class->constructed = gcal_night_light_monitor_constructed;
+  object_class->get_property = gcal_night_light_monitor_get_property;
+  object_class->set_property = gcal_night_light_monitor_set_property;
+
+  properties[PROP_MANAGER] = g_param_spec_object ("manager",
+                                                  "Manager",
+                                                  "Manager",
+                                                  GCAL_TYPE_MANAGER,
+                                                  G_PARAM_READWRITE | G_PARAM_CONSTRUCT_ONLY | G_PARAM_STATIC_STRINGS);
+
+  g_object_class_install_properties (object_class, N_PROPS, properties);
+}
+
+static void
+gcal_night_light_monitor_init (GcalNightLightMonitor *self)
+{
+}
+
+GcalNightLightMonitor*
+gcal_night_light_monitor_new (GcalManager *manager)
+{
+  return g_object_new (GCAL_TYPE_NIGHT_LIGHT_MONITOR,
+                       "manager", manager,
+                       NULL);
+}

src/gcal-night-light-monitor.h

@@ -0,0 +1,34 @@
+/* gcal-night-light-monitor.h
+ *
+ * Copyright 2018 Georges Basile Stavracas Neto <georges.stavracas@gmail.com>
+ *
+ * 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, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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/>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
+#pragma once
+
+#include "gcal-manager.h"
+#include "gcal-window.h"
+
+G_BEGIN_DECLS
+
+#define GCAL_TYPE_NIGHT_LIGHT_MONITOR (gcal_night_light_monitor_get_type())
+
+G_DECLARE_FINAL_TYPE (GcalNightLightMonitor, gcal_night_light_monitor, GCAL, NIGHT_LIGHT_MONITOR, GObject)
+
+GcalNightLightMonitor* gcal_night_light_monitor_new              (GcalManager        *manager);
+
+G_END_DECLS

src/meson.build

@@ -43,6 +43,7 @@ sources = files(
   'gcal-log.c',
   'gcal-manager.c',
   'gcal-multi-choice.c',
+  'gcal-night-light-monitor.c',
   'gcal-quick-add-popover.c',
   'gcal-recurrence.c',
   'gcal-search-popover.c',