[gtksourceview] print: implement TODO to ignore tags

[Christian Hergert <chergert src gnome org>]

commit 3f944e2ff2c6125d08a51818d315c4579506f658
Author: Christian Hergert <chergert redhat com>
Date:   Sun Jul 25 13:56:48 2021 -0700

    print: implement TODO to ignore tags
    
    This can be used to ignore things like spellcheck tags when printing.

 gtksourceview/gtksourceprintcompositor.c | 51 +++++++++++++++++++++++++-------
 gtksourceview/gtksourceprintcompositor.h |  3 ++
 2 files changed, 43 insertions(+), 11 deletions(-)
---
diff --git a/gtksourceview/gtksourceprintcompositor.c b/gtksourceview/gtksourceprintcompositor.c
index 495ed801..1c359320 100644
--- a/gtksourceview/gtksourceprintcompositor.c
+++ b/gtksourceview/gtksourceprintcompositor.c
@@ -154,6 +154,8 @@ typedef struct
 
        GtkTextMark             *pagination_mark;
 
+       GHashTable              *ignored_tags;
+
 #ifdef GTK_SOURCE_PROFILER_ENABLED
        gint64                   pagination_timer;
 #endif
@@ -305,6 +307,15 @@ gtk_source_print_compositor_set_property (GObject      *object,
        {
                case PROP_BUFFER:
                        priv->buffer = GTK_SOURCE_BUFFER (g_value_dup_object (value));
+                       if (priv->buffer)
+                       {
+                               GtkTextTag *tag = _gtk_source_buffer_get_bracket_match_tag (priv->buffer);
+
+                               if (tag)
+                               {
+                                       gtk_source_print_compositor_ignore_tag (compositor, tag);
+                               }
+                       }
                        break;
                case PROP_TAB_WIDTH:
                        gtk_source_print_compositor_set_tab_width (compositor,
@@ -357,6 +368,8 @@ gtk_source_print_compositor_finalize (GObject *object)
        GtkSourcePrintCompositor *compositor = GTK_SOURCE_PRINT_COMPOSITOR (object);
        GtkSourcePrintCompositorPrivate *priv = gtk_source_print_compositor_get_instance_private (compositor);
 
+       g_clear_pointer (&priv->ignored_tags, g_hash_table_unref);
+
        if (priv->pages != NULL)
                g_array_free (priv->pages, TRUE);
 
@@ -680,6 +693,7 @@ gtk_source_print_compositor_init (GtkSourcePrintCompositor *compositor)
        GtkSourcePrintCompositorPrivate *priv = gtk_source_print_compositor_get_instance_private (compositor);
 
        priv->buffer = NULL;
+       priv->ignored_tags = g_hash_table_new (NULL, NULL);
 
        priv->tab_width = DEFAULT_TAB_WIDTH;
        priv->wrap_mode = GTK_WRAP_NONE;
@@ -2223,22 +2237,12 @@ calculate_page_size_and_margins (GtkSourcePrintCompositor *compositor,
                                 convert_to_mm (get_text_height (compositor), GTK_UNIT_POINTS));
 }
 
-/* TODO: maybe we should have a public api to set
- * which tags need to be printed and which should not.
- * For now we special case bracket matches.
- */
 static gboolean
 ignore_tag (GtkSourcePrintCompositor *compositor,
             GtkTextTag               *tag)
 {
        GtkSourcePrintCompositorPrivate *priv = gtk_source_print_compositor_get_instance_private (compositor);
-       GtkTextTag *bm_tag;
-
-       bm_tag = _gtk_source_buffer_get_bracket_match_tag (priv->buffer);
-       if ((bm_tag != NULL) && (tag == bm_tag))
-               return TRUE;
-
-       return FALSE;
+       return tag ? g_hash_table_contains (priv->ignored_tags, tag) : FALSE;
 }
 
 static GSList *
@@ -3301,3 +3305,28 @@ gtk_source_print_compositor_draw_page (GtkSourcePrintCompositor *compositor,
                gtk_text_iter_forward_line (&start);
        }
 }
+
+/**
+ * gtk_source_print_compositor_ignore_tag:
+ * @compositor: a #GtkSourcePrintCompositor
+ * @tag: a #GtkTextTag
+ *
+ * Specifies a tag whose style should be ignored when compositing the
+ * document to the printable page.
+ *
+ * Since: 5.2
+ */
+void
+gtk_source_print_compositor_ignore_tag (GtkSourcePrintCompositor *compositor,
+                                        GtkTextTag               *tag)
+{
+       GtkSourcePrintCompositorPrivate *priv = gtk_source_print_compositor_get_instance_private (compositor);
+
+       g_return_if_fail (GTK_SOURCE_IS_PRINT_COMPOSITOR (compositor));
+       g_return_if_fail (!tag || GTK_IS_TEXT_TAG (tag));
+
+       if (tag != NULL)
+       {
+               g_hash_table_add (priv->ignored_tags, tag);
+       }
+}
diff --git a/gtksourceview/gtksourceprintcompositor.h b/gtksourceview/gtksourceprintcompositor.h
index 1cf2d80a..44014472 100644
--- a/gtksourceview/gtksourceprintcompositor.h
+++ b/gtksourceview/gtksourceprintcompositor.h
@@ -150,5 +150,8 @@ GTK_SOURCE_AVAILABLE_IN_ALL
 void                      gtk_source_print_compositor_draw_page                  (GtkSourcePrintCompositor 
*compositor,
                                                                                   GtkPrintContext          
*context,
                                                                                   gint                      
page_nr);
+GTK_SOURCE_AVAILABLE_IN_5_2
+void                      gtk_source_print_compositor_ignore_tag                 (GtkSourcePrintCompositor 
*compositor,
+                                                                                  GtkTextTag               
*tag);
 
 G_END_DECLS