Bug 631934 - Interaction between Old text parameters and new region specific text attributes

This patch inserts GimpText's property values as attributes into the
rendered markup and work transparently for both the tool options and
the text PDB API.

app/text/gimptextlayout.c

@@ -20,10 +20,13 @@
 
 #include "config.h"
 
+#include <string.h>
+
 #include <gegl.h>
 #include <pango/pangocairo.h>
 
 #include "libgimpbase/gimpbase.h"
+#include "libgimpcolor/gimpcolor.h"
 #include "libgimpmath/gimpmath.h"
 
 #include "text-types.h"
@@ -49,7 +52,7 @@ struct _GimpTextLayout
 static void           gimp_text_layout_finalize   (GObject        *object);
 
 static void           gimp_text_layout_position   (GimpTextLayout *layout);
-static void           gimp_text_layout_set_attrs  (GimpTextLayout *layout);
+static void           gimp_text_layout_set_markup (GimpTextLayout *layout);
 
 static PangoContext * gimp_text_get_pango_context (GimpText       *text,
                                                    gdouble         xres,
@@ -144,14 +147,7 @@ gimp_text_layout_new (GimpText  *text,
   pango_layout_set_font_description (layout->layout, font_desc);
   pango_font_description_free (font_desc);
 
-  gimp_text_layout_set_attrs (layout);
-
-  if (text->markup)
-    pango_layout_set_markup (layout->layout, text->markup, -1);
-  else if (text->text)
-    pango_layout_set_text (layout->layout, text->text, -1);
-  else
-    pango_layout_set_text (layout->layout, NULL, 0);
+  gimp_text_layout_set_markup (layout);
 
   switch (text->justify)
     {
@@ -458,40 +454,113 @@ gimp_text_layout_untransform_distance (GimpTextLayout *layout,
     }
 }
 
-static void
-gimp_text_layout_set_attrs (GimpTextLayout *layout)
+static gboolean
+gimp_text_layout_split_markup (const gchar  *markup,
+                               gchar       **open_tag,
+                               gchar       **content,
+                               gchar       **close_tag)
 {
-  GimpText       *text = layout->text;
-  PangoAttrList  *attrs;
-  PangoAttribute *attr;
+  gchar *p_open;
+  gchar *p_close;
+
+  p_open = strstr (markup, "<markup>");
+  if (! p_open)
+    return FALSE;
+
+  *open_tag = g_strndup (markup, p_open - markup + strlen ("<markup>"));
+
+  p_close = g_strrstr (markup, "</markup>");
+  if (! p_close)
+    {
+      g_free (*open_tag);
+      return FALSE;
+    }
+
+  *close_tag = g_strdup (p_close);
 
-  attrs = pango_layout_get_attributes (layout->layout);
-  if (attrs)
-    pango_attr_list_ref (attrs);
+  if (p_open + strlen ("<markup>") < p_close)
+    {
+      *content = g_strndup (p_open + strlen ("<markup>"),
+                            p_close - p_open - strlen ("<markup>"));
+    }
   else
-    attrs = pango_attr_list_new ();
+    {
+      *content = g_strdup ("");
+    }
+
+  return TRUE;
+}
+
+static gchar *
+gimp_text_layout_apply_tags (GimpTextLayout *layout,
+                             const gchar    *markup)
+{
+  GimpText *text = layout->text;
+  gchar    *result;
 
-  attr = pango_attr_foreground_new (text->color.r * 65535,
-                                    text->color.g * 65535,
-                                    text->color.b * 65535);
+  {
+    guchar r, g, b;
 
-  attr->start_index = 0;
-  attr->end_index   = -1;
+    gimp_rgb_get_uchar (&text->color, &r, &g, &b);
 
-  pango_attr_list_insert (attrs, attr);
+    result = g_strdup_printf ("<span color=\"#%02x%02x%02x\">%s</span>",
+                              r, g, b, markup);
+  }
 
   if (fabs (text->letter_spacing) > 0.1)
     {
-      attr = pango_attr_letter_spacing_new (text->letter_spacing * PANGO_SCALE);
+      gchar *tmp = g_strdup_printf ("<span letter_spacing=\"%d\">%s</span>",
+                                    (gint) (text->letter_spacing * PANGO_SCALE),
+                                    result);
+      g_free (result);
+      result = tmp;
+    }
 
-      attr->start_index = 0;
-      attr->end_index   = -1;
+  return result;
+}
+
+static void
+gimp_text_layout_set_markup (GimpTextLayout *layout)
+{
+  GimpText *text      = layout->text;
+  gchar    *open_tag  = NULL;
+  gchar    *content   = NULL;
+  gchar    *close_tag = NULL;
+  gchar    *tagged;
+  gchar    *markup;
+
+  if (text->markup)
+    {
+      if (! gimp_text_layout_split_markup (text->markup,
+                                           &open_tag, &content, &close_tag))
+        {
+          open_tag  = g_strdup ("<markup>");
+          content   = g_strdup ("");
+          close_tag = g_strdup ("</markup>");
+        }
+    }
+  else
+    {
+      open_tag  = g_strdup ("<markup>");
+      close_tag = g_strdup ("</markup>");
 
-      pango_attr_list_insert (attrs, attr);
+      if (text->text)
+        content = g_markup_escape_text (text->text, -1);
+      else
+        content = g_strdup ("");
     }
 
-  pango_layout_set_attributes (layout->layout, attrs);
-  pango_attr_list_unref (attrs);
+  tagged = gimp_text_layout_apply_tags (layout, content);
+
+  g_free (content);
+
+  markup = g_strconcat (open_tag, tagged, close_tag, NULL);
+
+  g_free (open_tag);
+  g_free (tagged);
+  g_free (close_tag);
+
+  pango_layout_set_markup (layout->layout, markup, -1);
 }
 
 static void