[recipes] Warn if the window is closed with unsaved changes

[Matthias Clasen <matthiasc src gnome org>]

commit 52e11bdb88c560c9e8041a0fd22f3c82412e5ddc
Author: Matthias Clasen <mclasen redhat com>
Date:   Fri Mar 10 23:56:02 2017 -0500

    Warn if the window is closed with unsaved changes
    
    Now that we track the unsaved status of the edit page,
    this is very easy to do.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=778201
    https://bugzilla.gnome.org/show_bug.cgi?id=779602

 src/gr-window.c  |   50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 src/gr-window.ui |    1 +
 2 files changed, 51 insertions(+), 0 deletions(-)
---
diff --git a/src/gr-window.c b/src/gr-window.c
index af72294..102833b 100644
--- a/src/gr-window.c
+++ b/src/gr-window.c
@@ -456,6 +456,55 @@ window_mapped_handler (GtkWidget *widget)
 }
 
 static void
+response_cb (GtkDialog *dialog,
+             int        response,
+             gpointer   data)
+{
+        GrWindow *window = data;
+
+        if (response == GTK_RESPONSE_YES)
+                gtk_widget_destroy (GTK_WIDGET (window));
+        else
+                gtk_widget_destroy (GTK_WIDGET (dialog));
+}
+
+static gboolean
+window_delete_handler (GtkWidget *widget)
+{
+        GrWindow *window = GR_WINDOW (widget);
+        const char *visible;
+        gboolean unsaved;
+
+        visible = gtk_stack_get_visible_child_name (GTK_STACK (window->main_stack));
+        g_object_get (window->edit_page, "unsaved", &unsaved, NULL);
+
+        if (strcmp (visible, "edit") == 0 && unsaved) {
+                GtkWidget *dialog;
+                GrRecipe *recipe;
+                g_autofree char *text = NULL;
+
+                recipe = gr_edit_page_get_recipe (GR_EDIT_PAGE (window->edit_page));
+                if (recipe)
+                        text = g_strdup_printf (_("The “%s” recipe has unsaved changes.\nClose the window 
anyway?"),
+                                                gr_recipe_get_name (recipe));
+                else
+                        text = g_strdup (_("The new recipe has not been saved.\nClose the window anyway?"));
+
+                dialog = gtk_message_dialog_new (GTK_WINDOW (window),
+                                                 GTK_DIALOG_MODAL|GTK_DIALOG_DESTROY_WITH_PARENT,
+                                                 GTK_MESSAGE_QUESTION,
+                                                 GTK_BUTTONS_YES_NO,
+                                                 "%s", text);
+                g_signal_connect (dialog, "response", G_CALLBACK (response_cb), window);
+                gtk_widget_show (dialog);
+
+                return TRUE;
+        }
+
+        return FALSE;
+}
+
+static void
 hide_or_show_header_end_stack (GObject    *object,
                                GParamSpec *pspec,
                                GrWindow   *window)
@@ -760,6 +809,7 @@ gr_window_class_init (GrWindowClass *klass)
         gtk_widget_class_bind_template_callback (widget_class, window_keypress_handler_before);
         gtk_widget_class_bind_template_callback (widget_class, window_buttonpress_handler);
         gtk_widget_class_bind_template_callback (widget_class, window_mapped_handler);
+        gtk_widget_class_bind_template_callback (widget_class, window_delete_handler);
         gtk_widget_class_bind_template_callback (widget_class, do_undo);
         gtk_widget_class_bind_template_callback (widget_class, close_undo);
         gtk_widget_class_bind_template_callback (widget_class, do_remind);
diff --git a/src/gr-window.ui b/src/gr-window.ui
index a8021e3..ea7de13 100644
--- a/src/gr-window.ui
+++ b/src/gr-window.ui
@@ -6,6 +6,7 @@
     <signal name="key-press-event" handler="window_keypress_handler_before"/>
     <signal name="key-press-event" handler="window_keypress_handler" after="yes"/>
     <signal name="button-press-event" handler="window_buttonpress_handler" after="yes"/>
+    <signal name="delete-event" handler="window_delete_handler"/>
     <signal name="map" handler="window_mapped_handler" after="yes"/>
     <child type="titlebar">
       <object class="GtkHeaderBar" id="header">