[gimp] app: add gimp_pdb_image_get_guide() and use it in the guide PDB wrappers

[Michael Natterer <mitch src gnome org>]

commit c1f7ec52a8da8c7d80566a607ff6ec5aa54cbdce
Author: Michael Natterer <mitch gimp org>
Date:   Thu Jul 10 20:24:10 2014 +0200

    app: add gimp_pdb_image_get_guide() and use it in the guide PDB wrappers
    
    It returns a proper error message if a guide ID doesn't exist.

 app/pdb/gimppdb-utils.c     |   24 ++++++++++++++++++++++++
 app/pdb/gimppdb-utils.h     |    4 ++++
 app/pdb/guides-cmds.c       |   17 ++++++++++++++---
 tools/pdbgen/pdb/guides.pdb |   18 ++++++++++++++----
 4 files changed, 56 insertions(+), 7 deletions(-)
---
diff --git a/app/pdb/gimppdb-utils.c b/app/pdb/gimppdb-utils.c
index 4000952..b8d71d5 100644
--- a/app/pdb/gimppdb-utils.c
+++ b/app/pdb/gimppdb-utils.c
@@ -30,6 +30,7 @@
 #include "core/gimpdatafactory.h"
 #include "core/gimpdrawable.h"
 #include "core/gimpimage.h"
+#include "core/gimpimage-guides.h"
 #include "core/gimpitem.h"
 
 #include "text/gimptextlayer.h"
@@ -678,6 +679,29 @@ gimp_pdb_image_is_not_precision (GimpImage      *image,
   return FALSE;
 }
 
+GimpGuide *
+gimp_pdb_image_get_guide (GimpImage  *image,
+                          gint        guide_ID,
+                          GError    **error)
+{
+  GimpGuide *guide;
+
+  g_return_val_if_fail (GIMP_IS_IMAGE (image), NULL);
+  g_return_val_if_fail (error == NULL || *error == NULL, NULL);
+
+  guide = gimp_image_get_guide (image, guide_ID);
+
+  if (guide)
+    return guide;
+
+  g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
+               _("Image '%s' (%d) does not contain guide with ID %d"),
+               gimp_image_get_display_name (image),
+               gimp_image_get_ID (image),
+               guide_ID);
+  return NULL;
+}
+
 GimpStroke *
 gimp_pdb_get_vectors_stroke (GimpVectors        *vectors,
                              gint                stroke_ID,
diff --git a/app/pdb/gimppdb-utils.h b/app/pdb/gimppdb-utils.h
index 9168b85..3d1dd4f 100644
--- a/app/pdb/gimppdb-utils.h
+++ b/app/pdb/gimppdb-utils.h
@@ -96,6 +96,10 @@ gboolean        gimp_pdb_image_is_not_precision (GimpImage          *image,
                                                  GimpPrecision       precision,
                                                  GError            **error);
 
+GimpGuide     * gimp_pdb_image_get_guide        (GimpImage          *image,
+                                                 gint                guide_ID,
+                                                 GError            **error);
+
 GimpStroke    * gimp_pdb_get_vectors_stroke     (GimpVectors        *vectors,
                                                  gint                stroke_ID,
                                                  GimpPDBItemModify   modify,
diff --git a/app/pdb/guides-cmds.c b/app/pdb/guides-cmds.c
index 6047b4a..42f6294 100644
--- a/app/pdb/guides-cmds.c
+++ b/app/pdb/guides-cmds.c
@@ -34,9 +34,13 @@
 #include "core/gimpparamspecs.h"
 
 #include "gimppdb.h"
+#include "gimppdberror.h"
+#include "gimppdb-utils.h"
 #include "gimpprocedure.h"
 #include "internal-procs.h"
 
+#include "gimp-intl.h"
+
 
 static GimpValueArray *
 image_add_hguide_invoker (GimpProcedure         *procedure,
@@ -133,7 +137,7 @@ image_delete_guide_invoker (GimpProcedure         *procedure,
 
   if (success)
     {
-      GimpGuide *g = gimp_image_get_guide (image, guide);
+      GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
       if (g)
         gimp_image_remove_guide (image, g, TRUE);
@@ -168,6 +172,13 @@ image_find_next_guide_invoker (GimpProcedure         *procedure,
 
       if (g)
         next_guide = gimp_guide_get_ID (g);
+
+      if (! success)
+        g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
+                     _("Image '%s' (%d) does not contain guide with ID %d"),
+                     gimp_image_get_display_name (image),
+                     gimp_image_get_ID (image),
+                     guide);
     }
 
   return_vals = gimp_procedure_get_return_values (procedure, success,
@@ -198,7 +209,7 @@ image_get_guide_orientation_invoker (GimpProcedure         *procedure,
 
   if (success)
     {
-      GimpGuide *g = gimp_image_get_guide (image, guide);
+      GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
       if (g)
         orientation = gimp_guide_get_orientation (g);
@@ -234,7 +245,7 @@ image_get_guide_position_invoker (GimpProcedure         *procedure,
 
   if (success)
     {
-      GimpGuide *g = gimp_image_get_guide (image, guide);
+      GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
       if (g)
         position = gimp_guide_get_position (g);
diff --git a/tools/pdbgen/pdb/guides.pdb b/tools/pdbgen/pdb/guides.pdb
index 7b16ebd..2926522 100644
--- a/tools/pdbgen/pdb/guides.pdb
+++ b/tools/pdbgen/pdb/guides.pdb
@@ -116,7 +116,7 @@ HELP
     %invoke = (
        code => <<'CODE'
 {
-  GimpGuide *g = gimp_image_get_guide (image, guide);
+  GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
   if (g)
     gimp_image_remove_guide (image, g, TRUE);
@@ -158,6 +158,13 @@ HELP
 
   if (g)
     next_guide = gimp_guide_get_ID (g);
+
+  if (! success)
+    g_set_error (error, GIMP_PDB_ERROR, GIMP_PDB_ERROR_INVALID_ARGUMENT,
+                 _("Image '%s' (%d) does not contain guide with ID %d"),
+                 gimp_image_get_display_name (image),
+                 gimp_image_get_ID (image),
+                 guide);
 }
 CODE
     );
@@ -190,7 +197,7 @@ HELP
     %invoke = (
        code => <<'CODE'
 {
-  GimpGuide *g = gimp_image_get_guide (image, guide);
+  GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
   if (g)
     orientation = gimp_guide_get_orientation (g);
@@ -227,7 +234,7 @@ HELP
     %invoke = (
        code => <<'CODE'
 {
-  GimpGuide *g = gimp_image_get_guide (image, guide);
+  GimpGuide *g = gimp_pdb_image_get_guide (image, guide, error);
 
   if (g)
     position = gimp_guide_get_position (g);
@@ -241,7 +248,10 @@ CODE
 
 @headers = qw("core/gimpguide.h"
               "core/gimpimage-guides.h"
-              "core/gimpimage-undo-push.h");
+              "core/gimpimage-undo-push.h"
+              "gimppdb-utils.h"
+              "gimppdberror.h"
+              "gimp-intl.h");
 
 @procs = qw(image_add_hguide image_add_vguide
             image_delete_guide