[gspell/wip/entry: 4/6] Entry: apply underlines to all words

[Sébastien Wilmet <swilmet src gnome org>]

commit 039bb2cc25836408926e4903070f78da1bfe9ae3
Author: Sébastien Wilmet <swilmet gnome org>
Date:   Fri Oct 28 14:07:11 2016 +0200

    Entry: apply underlines to all words

 gspell/gspell-entry.c |  112 ++++++++++++++++++++++++++++++++++++++++++------
 1 files changed, 98 insertions(+), 14 deletions(-)
---
diff --git a/gspell/gspell-entry.c b/gspell/gspell-entry.c
index 04626b0..3f30c5f 100644
--- a/gspell/gspell-entry.c
+++ b/gspell/gspell-entry.c
@@ -18,6 +18,7 @@
  */
 
 #include "gspell-entry.h"
+#include "gspell-entry-utils.h"
 
 /**
  * SECTION:entry
@@ -54,10 +55,35 @@ enum
 
 G_DEFINE_TYPE (GspellEntry, gspell_entry, G_TYPE_OBJECT)
 
+static gboolean
+remove_underlines_filter (PangoAttribute *attr,
+                         gpointer        user_data)
+{
+       return (attr->klass->type == PANGO_ATTR_UNDERLINE ||
+               attr->klass->type == PANGO_ATTR_UNDERLINE_COLOR);
+}
+
+static void
+remove_all_underlines (GspellEntry *gspell_entry)
+{
+       PangoAttrList *attr_list;
+
+       attr_list = gtk_entry_get_attributes (gspell_entry->entry);
+
+       if (attr_list == NULL)
+       {
+               return;
+       }
+
+       pango_attr_list_filter (attr_list,
+                               remove_underlines_filter,
+                               NULL);
+}
+
 static void
-apply_underline (GspellEntry *gspell_entry,
-                guint        byte_start,
-                guint        byte_end)
+insert_underline (GspellEntry *gspell_entry,
+                 guint        byte_start,
+                 guint        byte_end)
 {
        PangoAttribute *attr_underline;
        PangoAttribute *attr_underline_color;
@@ -73,21 +99,69 @@ apply_underline (GspellEntry *gspell_entry,
 
        attr_list = gtk_entry_get_attributes (gspell_entry->entry);
 
-       if (attr_list != NULL)
-       {
-               pango_attr_list_change (attr_list, attr_underline);
-               pango_attr_list_change (attr_list, attr_underline_color);
-       }
-       else
+       if (attr_list == NULL)
        {
                attr_list = pango_attr_list_new ();
-
-               pango_attr_list_change (attr_list, attr_underline);
-               pango_attr_list_change (attr_list, attr_underline_color);
-
                gtk_entry_set_attributes (gspell_entry->entry, attr_list);
                pango_attr_list_unref (attr_list);
        }
+
+       /* Do not use pango_attr_list_change(), because all previous underlines
+        * are anyway removed by remove_all_underlines().
+        */
+       pango_attr_list_insert (attr_list, attr_underline);
+       pango_attr_list_insert (attr_list, attr_underline_color);
+}
+
+static void
+recheck_all (GspellEntry *gspell_entry)
+{
+       PangoAttrList *attr_list;
+       GSList *words;
+       GSList *l;
+
+       words = _gspell_entry_utils_get_words (gspell_entry->entry);
+
+       for (l = words; l != NULL; l = l->next)
+       {
+               GspellEntryWord *cur_word = l->data;
+
+               insert_underline (gspell_entry,
+                                 cur_word->byte_start,
+                                 cur_word->byte_end);
+       }
+
+       g_slist_free_full (words, _gspell_entry_word_free);
+
+       /* If more attributes have been added to an existing PangoAttrList,
+        * GtkEntry doesn't know that the :attributes property has been
+        * modified. Without this code, GtkEntry can become buggy, especially
+        * with multi-byte characters (displaying them as unknown char boxes).
+        */
+       attr_list = gtk_entry_get_attributes (gspell_entry->entry);
+       gtk_entry_set_attributes (gspell_entry->entry, attr_list);
+}
+
+/* Connect to the ::changed signal before/after, so that other features (in
+ * other libraries or apps) can insert other underline attributes (e.g. for
+ * grammar checking) in another phase of the ::changed signal emission.
+ *
+ * But the GtkEntry API is not as nice as the GtkTextView API for inserting
+ * tags, setting priorities on them, etc. So, do the best that we can with the
+ * current GtkEntry API. If you find a better solution...
+ */
+static void
+changed_before_cb (GtkEditable *editable,
+                  GspellEntry *gspell_entry)
+{
+       remove_all_underlines (gspell_entry);
+}
+
+static void
+changed_after_cb (GtkEditable *editable,
+                 GspellEntry *gspell_entry)
+{
+       recheck_all (gspell_entry);
 }
 
 static void
@@ -99,7 +173,17 @@ set_entry (GspellEntry *gspell_entry,
        g_assert (gspell_entry->entry == NULL);
        gspell_entry->entry = gtk_entry;
 
-       apply_underline (gspell_entry, 0, 3);
+       g_signal_connect_object (gtk_entry,
+                                "changed",
+                                G_CALLBACK (changed_before_cb),
+                                gspell_entry,
+                                0);
+
+       g_signal_connect_object (gtk_entry,
+                                "changed",
+                                G_CALLBACK (changed_after_cb),
+                                gspell_entry,
+                                G_CONNECT_AFTER);
 
        g_object_notify (G_OBJECT (gspell_entry), "entry");
 }