[gnome-calendar] utils: add dialog to modify recurring events

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit cbc9fe7be165e32974295675c9890187966f7f3f
Author: Yash Singh <yashdev10p gmail com>
Date:   Thu Jun 8 18:16:19 2017 +0530

    utils: add dialog to modify recurring events
    
    Whenever a user chooses to modify an event which is
    recurring, a new dialog will open automatically when
    the user clicks 'Done' or 'Delete' in edit-dialog,
    after making the desired changes. This new dialog
    will ask the user to choose the set of events to
    which the changes will be applied. The options
    include 'This Event Only', 'Subsequent Events'
    and 'All Events'. The function returns true and
    the changes take place only if the user chooses any
    option other than 'Cancel' or <Alt+F4>.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=782755

 src/gcal-utils.c |   80 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 src/gcal-utils.h |    4 +++
 2 files changed, 84 insertions(+), 0 deletions(-)
---
diff --git a/src/gcal-utils.c b/src/gcal-utils.c
index c3cb35d..384860d 100644
--- a/src/gcal-utils.c
+++ b/src/gcal-utils.c
@@ -1150,3 +1150,83 @@ is_source_enabled (ESource *source)
 
   return e_source_selectable_get_selected (selectable);
 }
+
+/**
+ * ask_recurrence_modification_type:
+ * @parent: a #GtkWidget
+ * @modtype: an #ECalObjModType
+ * @source: an #ESource
+ *
+ * Assigns the appropriate modtype while modifying an event
+ * based on user's choice in the GtkMessageDialog that pops up.
+ * The modtype helps the user choose the part of recurrent events
+ * to modify. Such as Only This Event, Subsequent events
+ * or All events.
+ *
+ * Returns: %TRUE if user chooses appropriate option and
+ * @modtype is assigned, %FALSE otherwise.
+ */
+gboolean
+ask_recurrence_modification_type (GtkWidget      *parent,
+                                  ECalObjModType *modtype,
+                                  ESource         source)
+{
+  GtkWidget *dialog;
+  GtkDialogFlags flags;
+  gint result;
+  gboolean is_set;
+  EClient *client;
+
+  flags = GTK_DIALOG_MODAL | GTK_DIALOG_DESTROY_WITH_PARENT;
+  *modtype = E_CAL_OBJ_MOD_THIS;
+
+  dialog = gtk_message_dialog_new (GTK_WINDOW (parent),
+                                   flags,
+                                   GTK_MESSAGE_QUESTION,
+                                   GTK_BUTTONS_NONE,
+                                   _("The event you are trying to modify is recurring. The changes you have 
selected should be applied to:"));
+
+  gtk_dialog_add_buttons (GTK_DIALOG (dialog),
+                          _("_Cancel"),
+                          GTK_RESPONSE_CANCEL,
+                          _("_Only This Event"),
+                          GTK_RESPONSE_ACCEPT,
+                          NULL);
+
+  client = g_object_get_data (G_OBJECT (&source), "client");
+
+  if (!e_client_check_capability (E_CLIENT (client), CAL_STATIC_CAPABILITY_NO_THISANDFUTURE))
+    gtk_dialog_add_button (GTK_DIALOG (dialog), _("_Subsequent events"), GTK_RESPONSE_OK);
+
+  gtk_dialog_add_button (GTK_DIALOG (dialog), _("_All events"), GTK_RESPONSE_YES);
+
+  gtk_window_set_transient_for (GTK_WINDOW (dialog), GTK_WINDOW (parent));
+
+  result = gtk_dialog_run (GTK_DIALOG (dialog));
+
+  switch (result)
+    {
+      case GTK_RESPONSE_CANCEL:
+        is_set = FALSE;
+        break;
+      case GTK_RESPONSE_ACCEPT:
+        *modtype = E_CAL_OBJ_MOD_THIS;
+        is_set = TRUE;
+        break;
+      case GTK_RESPONSE_OK:
+        *modtype = E_CAL_OBJ_MOD_THIS_AND_FUTURE;
+        is_set = TRUE;
+        break;
+      case GTK_RESPONSE_YES:
+        *modtype = E_CAL_OBJ_MOD_ALL;
+        is_set = TRUE;
+        break;
+      default:
+        is_set = FALSE;
+        break;
+    }
+
+  gtk_widget_destroy (GTK_WIDGET (dialog));
+
+  return is_set;
+}
diff --git a/src/gcal-utils.h b/src/gcal-utils.h
index b4ab0ce..37b1d82 100644
--- a/src/gcal-utils.h
+++ b/src/gcal-utils.h
@@ -139,4 +139,8 @@ gboolean        should_change_date_for_scroll                   (gdouble
 
 gboolean        is_source_enabled                               (ESource               *source);
 
+gboolean        ask_recurrence_modification_type                (GtkWidget             *parent,
+                                                                 ECalObjModType        *modtype,
+                                                                 ESource                source);
+
 #endif // __GCAL_UTILS_H__