[tepl] SpaceDrawerPrefs: add result viewer

[Sébastien Wilmet <swilmet src gnome org>]

commit e8418470f62cf2d0f2200739a7aa8eeb4e609ff9
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Thu Sep 24 22:48:34 2020 +0200

    SpaceDrawerPrefs: add result viewer

 tepl/tepl-space-drawer-prefs.c | 66 +++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 65 insertions(+), 1 deletion(-)
---
diff --git a/tepl/tepl-space-drawer-prefs.c b/tepl/tepl-space-drawer-prefs.c
index 719fdff..c777342 100644
--- a/tepl/tepl-space-drawer-prefs.c
+++ b/tepl/tepl-space-drawer-prefs.c
@@ -23,6 +23,7 @@ struct _TeplSpaceDrawerPrefsPrivate
        /* Owned */
        GtkSourceSpaceDrawer *space_drawer;
 
+       /* First column */
        GtkCheckButton *check_button_leading_tabs;
        GtkCheckButton *check_button_leading_spaces;
        GtkCheckButton *check_button_inside_text_tabs;
@@ -30,6 +31,9 @@ struct _TeplSpaceDrawerPrefsPrivate
        GtkCheckButton *check_button_trailing_tabs;
        GtkCheckButton *check_button_trailing_spaces;
        GtkCheckButton *check_button_newlines;
+
+       /* Second column */
+       GtkGrid *second_column_vgrid;
 };
 
 G_DEFINE_TYPE_WITH_PRIVATE (TeplSpaceDrawerPrefs, tepl_space_drawer_prefs, GTK_TYPE_GRID)
@@ -249,13 +253,65 @@ matrix_notify_cb (GtkSourceSpaceDrawer *space_drawer,
        set_check_buttons_state_according_to_matrix (prefs);
 }
 
+static gchar *
+result_viewer_get_buffer_content (void)
+{
+       const gchar *tab_desc = _("Tab");
+       const gchar *space_desc = _("Space");
+       const gchar *nbsp_desc = _("No-Break Space");
+       const gchar *narrow_nbsp_desc = _("Narrow No-Break Space");
+
+       return g_strconcat ("\t", tab_desc, "\t", tab_desc, "\t\n",
+                           " ", space_desc, " ", space_desc, " \n",
+                           "\xC2\xA0", nbsp_desc, "\xC2\xA0", nbsp_desc, "\xC2\xA0\n",
+                           "\xE2\x80\xAF", narrow_nbsp_desc, "\xE2\x80\xAF", narrow_nbsp_desc, 
"\xE2\x80\xAF",
+                           NULL);
+}
+
+static void
+add_result_viewer (TeplSpaceDrawerPrefs *prefs)
+{
+       GtkSourceView *view;
+       GtkTextBuffer *buffer;
+       gchar *buffer_content;
+       GtkSourceSpaceDrawer *space_drawer;
+       GtkWidget *scrolled_window;
+
+       gtk_container_add (GTK_CONTAINER (prefs->priv->second_column_vgrid),
+                          create_subtitle_label (_("Result")));
+
+       view = GTK_SOURCE_VIEW (gtk_source_view_new ());
+       gtk_source_view_set_show_line_numbers (view, TRUE);
+       gtk_text_view_set_editable (GTK_TEXT_VIEW (view), FALSE);
+       gtk_text_view_set_monospace (GTK_TEXT_VIEW (view), TRUE);
+
+       buffer = gtk_text_view_get_buffer (GTK_TEXT_VIEW (view));
+       buffer_content = result_viewer_get_buffer_content ();
+       gtk_text_buffer_set_text (buffer, buffer_content, -1);
+       g_free (buffer_content);
+
+       space_drawer = gtk_source_view_get_space_drawer (view);
+       gtk_source_space_drawer_set_enable_matrix (space_drawer, TRUE);
+       g_object_bind_property (prefs->priv->space_drawer, "matrix",
+                               space_drawer, "matrix",
+                               G_BINDING_DEFAULT | G_BINDING_SYNC_CREATE);
+
+       scrolled_window = gtk_scrolled_window_new (NULL, NULL);
+       gtk_widget_set_size_request (scrolled_window, 500, 120);
+       gtk_widget_set_margin_start (scrolled_window, 12);
+       gtk_scrolled_window_set_shadow_type (GTK_SCROLLED_WINDOW (scrolled_window), GTK_SHADOW_IN);
+       gtk_scrolled_window_set_overlay_scrolling (GTK_SCROLLED_WINDOW (scrolled_window), FALSE);
+       gtk_container_add (GTK_CONTAINER (scrolled_window), GTK_WIDGET (view));
+       gtk_container_add (GTK_CONTAINER (prefs->priv->second_column_vgrid), scrolled_window);
+}
+
 static void
 tepl_space_drawer_prefs_init (TeplSpaceDrawerPrefs *prefs)
 {
        prefs->priv = tepl_space_drawer_prefs_get_instance_private (prefs);
 
        gtk_orientable_set_orientation (GTK_ORIENTABLE (prefs), GTK_ORIENTATION_HORIZONTAL);
-       gtk_grid_set_column_spacing (GTK_GRID (prefs), 12);
+       gtk_grid_set_column_spacing (GTK_GRID (prefs), 24);
 
        g_object_set (prefs,
                      "margin", 6,
@@ -275,6 +331,14 @@ tepl_space_drawer_prefs_init (TeplSpaceDrawerPrefs *prefs)
                                 G_CALLBACK (matrix_notify_cb),
                                 prefs,
                                 0);
+
+       prefs->priv->second_column_vgrid = GTK_GRID (gtk_grid_new ());
+       gtk_orientable_set_orientation (GTK_ORIENTABLE (prefs->priv->second_column_vgrid),
+                                       GTK_ORIENTATION_VERTICAL);
+       gtk_grid_set_row_spacing (prefs->priv->second_column_vgrid, 6);
+       gtk_container_add (GTK_CONTAINER (prefs), GTK_WIDGET (prefs->priv->second_column_vgrid));
+       add_result_viewer (prefs);
+       gtk_widget_show_all (GTK_WIDGET (prefs->priv->second_column_vgrid));
 }
 
 /**