nav-bar: implemented today button

Implements today button between previous and forward buttons.

Fix bug #703316.

data/ui/nav_bar.ui

@@ -37,6 +37,28 @@
             <property name="position">0</property>
           </packing>
         </child>
+        <child>
+          <object class="GtkButton" id="today_button">
+            <property name="visible">True</property>
+            <property name="can_focus">True</property>
+            <property name="focus_on_click">False</property>
+            <style>
+              <class name="nav-button"/>
+            </style>
+            <child>
+              <object class="GtkLabel" id="today_label">
+                <property name="visible">True</property>
+                <property name="can_focus">False</property>
+                <property name="label" translatable="yes">Today</property>
+              </object>
+            </child>
+          </object>
+          <packing>
+            <property name="expand">False</property>
+            <property name="fill">True</property>
+            <property name="position">1</property>
+          </packing>
+        </child>
         <child>
           <object class="GtkButton" id="forward_button">
             <property name="visible">True</property>
@@ -56,7 +78,7 @@
           <packing>
             <property name="expand">False</property>
             <property name="fill">True</property>
-            <property name="position">1</property>
+            <property name="position">2</property>
           </packing>
         </child>
       </object>

src/gcal-nav-bar.c

@@ -26,6 +26,7 @@
 typedef struct
 {
   GtkWidget *back_button;
+  GtkWidget *today_button;
   GtkWidget *forward_button;
 
   GtkWidget *left_label;
@@ -88,6 +89,7 @@ gcal_nav_bar_class_init (GcalNavBarClass *klass)
 
   /* Bind internals widgets */
   gtk_widget_class_bind_template_child_private (widget_class, GcalNavBar, back_button);
+  gtk_widget_class_bind_template_child_private (widget_class, GcalNavBar, today_button);
   gtk_widget_class_bind_template_child_private (widget_class, GcalNavBar, forward_button);
   gtk_widget_class_bind_template_child_private (widget_class, GcalNavBar, left_label);
   gtk_widget_class_bind_template_child_private (widget_class, GcalNavBar, right_label);
@@ -174,6 +176,15 @@ gcal_nav_bar_get_prev_button (GcalNavBar *nav_bar)
   return priv->back_button;
 }
 
+GtkWidget*
+gcal_nav_bar_get_today_button (GcalNavBar *nav_bar)
+{
+  GcalNavBarPrivate *priv;
+
+  priv = gcal_nav_bar_get_instance_private (nav_bar);
+  return priv->today_button;
+}
+
 GtkWidget*
 gcal_nav_bar_get_next_button (GcalNavBar *nav_bar)
 {

src/gcal-nav-bar.h

@@ -50,6 +50,8 @@ GtkWidget*     gcal_nav_bar_new              (void);
 
 GtkWidget*     gcal_nav_bar_get_prev_button  (GcalNavBar *nav_bar);
 
+GtkWidget*     gcal_nav_bar_get_today_button (GcalNavBar *nav_bar);
+
 GtkWidget*     gcal_nav_bar_get_next_button  (GcalNavBar *nav_bar);
 
 G_END_DECLS

src/gcal-window.c

@@ -257,28 +257,39 @@ date_updated (GtkButton  *button,
 {
   GcalWindowPrivate *priv;
 
-  gboolean move_back;
+  gboolean move_back, move_today;
 
   priv = gcal_window_get_instance_private (GCAL_WINDOW (user_data));
 
+  move_today = gcal_nav_bar_get_today_button (GCAL_NAV_BAR (priv->nav_bar)) == (GtkWidget*) button;
   move_back = gcal_nav_bar_get_prev_button (GCAL_NAV_BAR (priv->nav_bar)) == (GtkWidget*) button;
 
-  switch (priv->active_view)
+  if (move_today)
     {
-    case GCAL_WINDOW_VIEW_DAY:
+      GcalManager *manager;
-      priv->active_date->day += 1 * (move_back ? -1 : 1);
+
-      break;
+      manager = get_manager (GCAL_WINDOW (user_data));
-    case GCAL_WINDOW_VIEW_WEEK:
+      *(priv->active_date) = icaltime_current_time_with_zone (gcal_manager_get_system_timezone (manager));
-      priv->active_date->day += 7 * (move_back ? -1 : 1);
+    }
-      break;
+  else
-    case GCAL_WINDOW_VIEW_MONTH:
+    {
-      priv->active_date->month += 1 * (move_back ? -1 : 1);
+      switch (priv->active_view)
-      break;
+        {
-    case GCAL_WINDOW_VIEW_YEAR:
+        case GCAL_WINDOW_VIEW_DAY:
-      priv->active_date->year += 1 * (move_back ? -1 : 1);
+          priv->active_date->day += 1 * (move_back ? -1 : 1);
-      break;
+          break;
-    case GCAL_WINDOW_VIEW_LIST:
+        case GCAL_WINDOW_VIEW_WEEK:
-      break;
+          priv->active_date->day += 7 * (move_back ? -1 : 1);
+          break;
+        case GCAL_WINDOW_VIEW_MONTH:
+          priv->active_date->month += 1 * (move_back ? -1 : 1);
+          break;
+        case GCAL_WINDOW_VIEW_YEAR:
+          priv->active_date->year += 1 * (move_back ? -1 : 1);
+          break;
+        case GCAL_WINDOW_VIEW_LIST:
+          break;
+        }
     }
   *(priv->active_date) = icaltime_normalize (*(priv->active_date));
   g_object_notify (user_data, "active-date");
@@ -1054,6 +1065,8 @@ gcal_window_constructed (GObject *object)
                     G_CALLBACK (view_changed), object);
   g_signal_connect (gcal_nav_bar_get_prev_button (GCAL_NAV_BAR (priv->nav_bar)),
                     "clicked", G_CALLBACK (date_updated), object);
+  g_signal_connect (gcal_nav_bar_get_today_button (GCAL_NAV_BAR (priv->nav_bar)),
+                    "clicked", G_CALLBACK (date_updated), object);
   g_signal_connect (gcal_nav_bar_get_next_button (GCAL_NAV_BAR (priv->nav_bar)),
                     "clicked", G_CALLBACK (date_updated), object);
 }