gimp/app/tools/gimptexttool.c

/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * GimpTextTool
 * Copyright (C) 2002-2004  Sven Neumann <sven@gimp.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include <gtk/gtk.h>

#include "libgimpbase/gimpbase.h"
#include "libgimpwidgets/gimpwidgets.h"

#include "tools-types.h"

#include "core/gimp.h"
#include "core/gimpcontext.h"
#include "core/gimpimage.h"
#include "core/gimpimage-undo.h"
#include "core/gimpimage-undo-push.h"
#include "core/gimplayer-floating-sel.h"
#include "core/gimptoolinfo.h"
#include "core/gimpundo.h"
#include "core/gimpundostack.h"

#include "config/gimpconfig.h"
#include "config/gimpconfig-utils.h"

#include "text/gimptext.h"
#include "text/gimptext-vectors.h"
#include "text/gimptextlayer.h"
#include "text/gimptextundo.h"

#include "widgets/gimpdialogfactory.h"
#include "widgets/gimphelp-ids.h"
#include "widgets/gimptexteditor.h"
#include "widgets/gimpviewabledialog.h"

#include "display/gimpdisplay.h"

#include "gimptextoptions.h"
#include "gimptexttool.h"
#include "gimptoolcontrol.h"

#include "gimp-intl.h"


#define TEXT_UNDO_TIMEOUT 3


/*  local function prototypes  */

static void      gimp_text_tool_class_init     (GimpTextToolClass *klass);
static void      gimp_text_tool_init           (GimpTextTool      *tool);
static GObject * gimp_text_tool_constructor    (GType              type,
                                                guint              n_params,
                                                GObjectConstructParam *params);
static void      gimp_text_tool_dispose        (GObject           *object);
static void      gimp_text_tool_finalize       (GObject           *object);

static void      gimp_text_tool_control        (GimpTool          *tool,
                                                GimpToolAction     action,
                                                GimpDisplay       *gdisp);
static void      gimp_text_tool_button_press   (GimpTool          *tool,
                                                GimpCoords        *coords,
                                                guint32            time,
                                                GdkModifierType    state,
                                                GimpDisplay       *gdisp);
static void      gimp_text_tool_cursor_update  (GimpTool          *tool,
                                                GimpCoords        *coords,
                                                GdkModifierType    state,
                                                GimpDisplay       *gdisp);

static void      gimp_text_tool_connect        (GimpTextTool      *text_tool,
                                                GimpTextLayer     *layer,
                                                GimpText          *text);
static void      gimp_text_tool_layer_notify   (GimpTextLayer     *layer,
                                                GParamSpec        *pspec,
                                                GimpTextTool      *text_tool);
static void      gimp_text_tool_proxy_notify   (GimpText          *text,
                                                GParamSpec        *pspec,
                                                GimpTextTool      *text_tool);
static void      gimp_text_tool_text_notify    (GimpText          *text,
                                                GParamSpec        *pspec,
                                                GimpTextTool      *text_tool);
static gboolean  gimp_text_tool_idle_apply     (GimpTextTool      *text_tool);
static void      gimp_text_tool_apply          (GimpTextTool      *text_tool);

static void      gimp_text_tool_create_vectors (GimpTextTool      *text_tool);
static void      gimp_text_tool_create_layer   (GimpTextTool      *text_tool,
                                                GimpText          *text);

static void      gimp_text_tool_editor         (GimpTextTool      *text_tool);
static void      gimp_text_tool_editor_update  (GimpTextTool      *text_tool);
static void      gimp_text_tool_text_changed   (GimpTextEditor    *editor,
                                                GimpTextTool      *text_tool);

static void      gimp_text_tool_set_image      (GimpTextTool      *text_tool,
                                                GimpImage         *image);
static gboolean  gimp_text_tool_set_drawable   (GimpTextTool      *text_tool,
                                                GimpDrawable      *drawable,
                                                gboolean           confirm);


/*  local variables  */

static GimpToolClass *parent_class = NULL;


/*  public functions  */

void
gimp_text_tool_register (GimpToolRegisterCallback  callback,
                         gpointer                  data)
{
  (* callback) (GIMP_TYPE_TEXT_TOOL,
                GIMP_TYPE_TEXT_OPTIONS,
                gimp_text_options_gui,
                GIMP_CONTEXT_FOREGROUND_MASK | GIMP_CONTEXT_FONT_MASK,
                "gimp-text-tool",
                _("Text"),
                _("Add text to the image"),
                N_("/Tools/Te_xt"), "T",
                NULL, GIMP_HELP_TOOL_TEXT,
                GIMP_STOCK_TOOL_TEXT,
                data);
}

GType
gimp_text_tool_get_type (void)
{
  static GType tool_type = 0;

  if (! tool_type)
    {
      static const GTypeInfo tool_info =
      {
        sizeof (GimpTextToolClass),
	(GBaseInitFunc) NULL,
	(GBaseFinalizeFunc) NULL,
	(GClassInitFunc) gimp_text_tool_class_init,
	NULL,           /* class_finalize */
	NULL,           /* class_data     */
	sizeof (GimpTextTool),
	0,              /* n_preallocs    */
	(GInstanceInitFunc) gimp_text_tool_init,
      };

      tool_type = g_type_register_static (GIMP_TYPE_TOOL,
					  "GimpTextTool",
                                          &tool_info, 0);
    }

  return tool_type;
}


/*  private functions  */

static void
gimp_text_tool_class_init (GimpTextToolClass *klass)
{
  GObjectClass  *object_class = G_OBJECT_CLASS (klass);
  GimpToolClass *tool_class   = GIMP_TOOL_CLASS (klass);

  parent_class = g_type_class_peek_parent (klass);

  object_class->constructor = gimp_text_tool_constructor;
  object_class->dispose     = gimp_text_tool_dispose;
  object_class->finalize    = gimp_text_tool_finalize;

  tool_class->control       = gimp_text_tool_control;
  tool_class->button_press  = gimp_text_tool_button_press;
  tool_class->cursor_update = gimp_text_tool_cursor_update;
}

static void
gimp_text_tool_init (GimpTextTool *text_tool)
{
  GimpTool *tool = GIMP_TOOL (text_tool);

  text_tool->proxy   = NULL;
  text_tool->pending = NULL;
  text_tool->idle_id = 0;

  text_tool->text    = NULL;
  text_tool->layer   = NULL;
  text_tool->image   = NULL;

  gimp_tool_control_set_scroll_lock (tool->control, TRUE);
  gimp_tool_control_set_preserve    (tool->control, TRUE);
  gimp_tool_control_set_tool_cursor (tool->control, GIMP_TEXT_TOOL_CURSOR);
}

static GObject *
gimp_text_tool_constructor (GType                  type,
                            guint                  n_params,
                            GObjectConstructParam *params)
{
  GObject         *object;
  GimpTextTool    *text_tool;
  GimpTextOptions *options;

  object = G_OBJECT_CLASS (parent_class)->constructor (type, n_params, params);

  text_tool = GIMP_TEXT_TOOL (object);
  options = GIMP_TEXT_OPTIONS (GIMP_TOOL (text_tool)->tool_info->tool_options);

  text_tool->proxy = g_object_new (GIMP_TYPE_TEXT, NULL);

  gimp_text_options_connect_text (options, text_tool->proxy);

  g_signal_connect_object (text_tool->proxy, "notify",
                           G_CALLBACK (gimp_text_tool_proxy_notify),
                           text_tool, 0);

  return object;
}

static void
gimp_text_tool_dispose (GObject *object)
{
  GimpTextTool *text_tool = GIMP_TEXT_TOOL (object);

  gimp_text_tool_set_drawable (text_tool, NULL, FALSE);

  G_OBJECT_CLASS (parent_class)->dispose (object);
}

static void
gimp_text_tool_finalize (GObject *object)
{
  GimpTextTool *text_tool = GIMP_TEXT_TOOL (object);

  if (text_tool->proxy)
    {
      g_object_unref (text_tool->proxy);
      text_tool->proxy = NULL;
    }

  G_OBJECT_CLASS (parent_class)->finalize (object);
}

static void
gimp_text_tool_control (GimpTool       *tool,
			GimpToolAction  action,
			GimpDisplay    *gdisp)
{
  GimpTextTool *text_tool = GIMP_TEXT_TOOL (tool);

  switch (action)
    {
    case PAUSE:
    case RESUME:
      break;

    case HALT:
      gimp_text_tool_set_drawable (text_tool, NULL, FALSE);
      break;
    }

  GIMP_TOOL_CLASS (parent_class)->control (tool, action, gdisp);
}

static void
gimp_text_tool_button_press (GimpTool        *tool,
			     GimpCoords      *coords,
			     guint32          time,
			     GdkModifierType  state,
			     GimpDisplay     *gdisp)
{
  GimpTextTool *text_tool = GIMP_TEXT_TOOL (tool);
  GimpText     *text      = text_tool->text;
  GimpDrawable *drawable;

  gimp_tool_control_activate (tool->control);
  tool->gdisp = gdisp;

  text_tool->x1 = coords->x;
  text_tool->y1 = coords->y;

  drawable = gimp_image_active_drawable (gdisp->gimage);

  gimp_text_tool_set_drawable (text_tool, drawable, FALSE);

  if (GIMP_IS_LAYER (drawable))
    {
      GimpItem *item = GIMP_ITEM (drawable);

      coords->x -= item->offset_x;
      coords->y -= item->offset_y;

      if (coords->x > 0 && coords->x < item->width &&
          coords->y > 0 && coords->y < item->height)
        {
          /*  did the user click on a text layer?  */
          if (gimp_text_tool_set_drawable (text_tool, drawable, TRUE))
            {
              /*  on second click, open the text editor  */
              if (text && text_tool->text == text)
                gimp_text_tool_editor (text_tool);

              return;
            }
        }
    }

  /*  create a new text layer  */
  gimp_text_tool_connect (text_tool, NULL, NULL);
  gimp_text_tool_editor (text_tool);
}

static void
gimp_text_tool_cursor_update (GimpTool        *tool,
			      GimpCoords      *coords,
			      GdkModifierType  state,
			      GimpDisplay     *gdisp)
{
  /* FIXME: should do something fancy here... */

  GIMP_TOOL_CLASS (parent_class)->cursor_update (tool, coords, state, gdisp);
}

static void
gimp_text_tool_connect (GimpTextTool  *text_tool,
                        GimpTextLayer *layer,
                        GimpText      *text)
{
  GimpTool *tool = GIMP_TOOL (text_tool);

  g_return_if_fail (text == NULL || (layer != NULL && layer->text == text));

  if (! text && text_tool->editor)
    gtk_widget_destroy (text_tool->editor);

  if (text_tool->text != text)
    {
      GimpTextOptions *options;
      GtkWidget       *button;

      options = GIMP_TEXT_OPTIONS (tool->tool_info->tool_options);
      button = g_object_get_data (G_OBJECT (options), "gimp-text-to-vectors");

      if (text_tool->text)
        {
          g_signal_handlers_disconnect_by_func (text_tool->text,
                                                gimp_text_tool_text_notify,
                                                text_tool);

          if (text_tool->pending)
            gimp_text_tool_apply (text_tool);

          if (button)
            {
              gtk_widget_set_sensitive (button, FALSE);
              g_signal_handlers_disconnect_by_func (button,
                                                    gimp_text_tool_create_vectors,
                                                    text_tool);
            }

          g_object_unref (text_tool->text);
          text_tool->text = NULL;

          g_object_set (text_tool->proxy, "text", NULL, NULL);
        }

      gimp_context_define_property (GIMP_CONTEXT (options),
                                    GIMP_CONTEXT_PROP_FOREGROUND,
                                    text != NULL);

      if (text)
        {
          gimp_config_sync (GIMP_CONFIG (text),
                            GIMP_CONFIG (text_tool->proxy), 0);

          text_tool->text = g_object_ref (text);

          g_signal_connect (text, "notify",
                            G_CALLBACK (gimp_text_tool_text_notify),
                            text_tool);

          if (button)
            {
              g_signal_connect_swapped (button, "clicked",
                                        G_CALLBACK (gimp_text_tool_create_vectors),
                                        text_tool);
              gtk_widget_set_sensitive (button, TRUE);
            }

          if (text_tool->editor)
            gimp_text_tool_editor_update (text_tool);
        }
    }

  if (text_tool->layer != layer)
    {
      if (text_tool->layer)
        {
          g_signal_handlers_disconnect_by_func (text_tool->layer,
                                                gimp_text_tool_layer_notify,
                                                text_tool);
          text_tool->layer = NULL;
        }

      text_tool->layer = layer;

      if (layer)
        g_signal_connect_object (text_tool->layer, "notify::modified",
                                 G_CALLBACK (gimp_text_tool_layer_notify),
                                 text_tool, 0);
    }
}

static void
gimp_text_tool_layer_notify (GimpTextLayer *layer,
                             GParamSpec    *pspec,
                             GimpTextTool  *text_tool)
{
  if (layer->modified)
    gimp_text_tool_connect (text_tool, NULL, NULL);
}

static void
gimp_text_tool_proxy_notify (GimpText     *text,
                             GParamSpec   *pspec,
                             GimpTextTool *text_tool)
{
  if (! text_tool->text)
    return;

  if ((pspec->flags & G_PARAM_READWRITE) == G_PARAM_READWRITE)
    {
      text_tool->pending = g_list_append (text_tool->pending, pspec);

      if (text_tool->idle_id)
        g_source_remove (text_tool->idle_id);

      text_tool->idle_id =
        g_idle_add_full (G_PRIORITY_LOW,
                         (GSourceFunc) gimp_text_tool_idle_apply, text_tool,
                         NULL);
    }
}

static void
gimp_text_tool_text_notify (GimpText     *text,
                            GParamSpec   *pspec,
                            GimpTextTool *text_tool)
{
  g_return_if_fail (text == text_tool->text);

  if ((pspec->flags & G_PARAM_READWRITE) == G_PARAM_READWRITE)
    {
      GValue value = { 0, };

      g_value_init (&value, pspec->value_type);

      g_object_get_property (G_OBJECT (text), pspec->name, &value);

      g_signal_handlers_block_by_func (text_tool->proxy,
                                       gimp_text_tool_proxy_notify,
                                       text_tool);

      g_object_set_property (G_OBJECT (text_tool->proxy), pspec->name, &value);

      g_signal_handlers_unblock_by_func (text_tool->proxy,
                                         gimp_text_tool_proxy_notify,
                                         text_tool);

      g_value_unset (&value);
    }

  if (text_tool->editor && strcmp (pspec->name, "text") == 0)
    gimp_text_tool_editor_update (text_tool);
}

static gboolean
gimp_text_tool_idle_apply (GimpTextTool *text_tool)
{
  text_tool->idle_id = 0;

  gimp_text_tool_apply (text_tool);

  return FALSE;
}

static void
gimp_text_tool_apply (GimpTextTool *text_tool)
{
  const GParamSpec *pspec = NULL;
  GimpImage        *image;
  GimpTextLayer    *layer;
  GObject          *src;
  GObject          *dest;
  GList            *list;
  gboolean          push_undo  = TRUE;
  gboolean          undo_group = FALSE;

  if (text_tool->idle_id)
    {
      g_source_remove (text_tool->idle_id);
      text_tool->idle_id = 0;
    }

  g_return_if_fail (text_tool->text != NULL);
  g_return_if_fail (text_tool->layer != NULL);

  layer = text_tool->layer;
  image = gimp_item_get_image (GIMP_ITEM (layer));

  g_return_if_fail (layer->text == text_tool->text);

  /*  Walk over the list of changes and figure out if we are changing
   *  a single property or need to push a full text undo.
   */
  for (list = text_tool->pending;
       list && list->next && list->next->data == list->data;
       list = list->next)
    /* do nothing */;

  if (g_list_length (list) == 1)
    pspec = list->data;

  if (pspec)
    {
      GimpUndo *undo = gimp_undo_stack_peek (image->undo_stack);

      /*  If we are changing a single property, we don't need to push
       *  an undo if all of the following is true:
       *   - the last item on the undo stack is a text undo
       *   - the redo stack is empty
       *   - the last undo changed the same text property on the same layer
       *   - the last undo happened less than TEXT_UNDO_TIMEOUT seconds ago
       */
      if (undo && GIMP_IS_TEXT_UNDO (undo) &&
          ! gimp_undo_stack_peek (image->redo_stack))
        {
          GimpTextUndo *text_undo = GIMP_TEXT_UNDO (undo);

          if (text_undo->pspec == pspec &&
              GIMP_ITEM_UNDO (undo)->item == GIMP_ITEM (layer))
            {
              guint now = time (NULL);

              if (now >= text_undo->time &&
                  now - text_undo->time < TEXT_UNDO_TIMEOUT)
                {
                  push_undo = FALSE;
                  text_undo->time = now;
                  gimp_undo_refresh_preview (undo);
                }
            }
        }
    }

  if (push_undo)
    {
      /*  If the layer contains a mask,
       *  gimp_text_layer_render() might have to resize it.
       */
      undo_group = ((GIMP_LAYER (layer)->mask != NULL) || layer->modified);
      if (undo_group)
        gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_TEXT, NULL);

      if (layer->modified)
        gimp_image_undo_push_drawable_mod (image, NULL, GIMP_DRAWABLE (layer));

      gimp_image_undo_push_text_layer (image, NULL, layer, pspec);
    }

  src  = G_OBJECT (text_tool->proxy);
  dest = G_OBJECT (text_tool->text);

  g_signal_handlers_block_by_func (dest,
                                   gimp_text_tool_text_notify, text_tool);

  g_object_freeze_notify (dest);

  for (; list; list = list->next)
    {
      GValue  value = { 0, };

      /*  look ahead and compress changes  */
      if (list->next && list->next->data == list->data)
        continue;

      pspec = list->data;

      g_value_init (&value, pspec->value_type);

      g_object_get_property (src,  pspec->name, &value);
      g_object_set_property (dest, pspec->name, &value);

      g_value_unset (&value);
    }

  g_list_free (text_tool->pending);
  text_tool->pending = NULL;

  g_object_thaw_notify (dest);

  g_signal_handlers_unblock_by_func (dest,
                                     gimp_text_tool_text_notify, text_tool);

  if (push_undo && undo_group)
    gimp_image_undo_group_end (image);

  gimp_image_flush (image);
}

static void
gimp_text_tool_create_vectors (GimpTextTool *text_tool)
{
  GimpVectors *vectors;

  if (! text_tool->text || ! text_tool->image)
    return;

  vectors = gimp_text_vectors_new (text_tool->image, text_tool->text);

  if (text_tool->layer)
    {
      gint x, y;

      gimp_item_offsets (GIMP_ITEM (text_tool->layer), &x, &y);
      gimp_item_translate (GIMP_ITEM (vectors), x, y, FALSE);
    }

  gimp_image_add_vectors (text_tool->image, vectors, -1);

  gimp_image_flush (text_tool->image);
}

static void
gimp_text_tool_create_layer (GimpTextTool *text_tool,
                             GimpText     *text)
{
  GimpTool  *tool = GIMP_TOOL (text_tool);
  GimpImage *image;
  GimpLayer *layer;

  if (text)
    {
      text = gimp_config_duplicate (GIMP_CONFIG (text));
    }
  else
    {
      g_object_set (text_tool->proxy,
                    "text",
                    gimp_text_editor_get_text (GIMP_TEXT_EDITOR (text_tool->editor)),
                    NULL);

      text = gimp_config_duplicate (GIMP_CONFIG (text_tool->proxy));
    }

  image = tool->gdisp->gimage;
  layer = gimp_text_layer_new (image, text);

  g_object_unref (text);

  if (! layer)
    return;

  gimp_text_tool_connect (text_tool, GIMP_TEXT_LAYER (layer), text);

  gimp_image_undo_group_start (image, GIMP_UNDO_GROUP_TEXT,
                               _("Add Text Layer"));

  if (gimp_image_floating_sel (image))
    floating_sel_anchor (gimp_image_floating_sel (image));

  GIMP_ITEM (layer)->offset_x = text_tool->x1;
  GIMP_ITEM (layer)->offset_y = text_tool->y1;

  gimp_image_add_layer (image, layer, -1);

  gimp_image_undo_group_end (image);

  gimp_image_flush (image);

  gimp_text_tool_set_drawable (text_tool, GIMP_DRAWABLE (layer), FALSE);
}

static void
gimp_text_tool_editor (GimpTextTool *text_tool)
{
  GimpTextOptions *options;

  if (text_tool->editor)
    {
      gtk_window_present (GTK_WINDOW (text_tool->editor));
      return;
    }

  options = GIMP_TEXT_OPTIONS (GIMP_TOOL (text_tool)->tool_info->tool_options);

  text_tool->editor = gimp_text_options_editor_new (options,
                                                    _("GIMP Text Editor"));

  g_object_add_weak_pointer (G_OBJECT (text_tool->editor),
			     (gpointer *) &text_tool->editor);

  gimp_dialog_factory_add_foreign (gimp_dialog_factory_from_name ("toplevel"),
                                   "gimp-text-tool-dialog",
                                   text_tool->editor);

  if (text_tool->text)
    gimp_text_editor_set_text (GIMP_TEXT_EDITOR (text_tool->editor),
                               text_tool->text->text, -1);

  g_signal_connect_object (text_tool->editor, "text_changed",
                           G_CALLBACK (gimp_text_tool_text_changed),
                           text_tool, 0);

  gtk_widget_show (text_tool->editor);
}

static void
gimp_text_tool_editor_update (GimpTextTool *text_tool)
{
  gchar *str = NULL;

  if (! text_tool->editor)
    return;

  if (text_tool->text)
    g_object_get (text_tool->text, "text", &str, NULL);

  g_signal_handlers_block_by_func (text_tool->editor,
                                   gimp_text_tool_text_changed, text_tool);

  gimp_text_editor_set_text (GIMP_TEXT_EDITOR (text_tool->editor),
                             str, str ? -1 : 0);

  g_signal_handlers_unblock_by_func (text_tool->editor,
                                     gimp_text_tool_text_changed, text_tool);

  g_free (str);
}

static void
gimp_text_tool_text_changed (GimpTextEditor *editor,
                             GimpTextTool   *text_tool)
{
  if (text_tool->text)
    {
      gchar *text;

      text = gimp_text_editor_get_text (GIMP_TEXT_EDITOR (text_tool->editor));

      g_object_set (text_tool->proxy, "text", text, NULL);

      g_free (text);
    }
  else
    {
      gimp_text_tool_create_layer (text_tool, NULL);
    }
}

#define  RESPONSE_NEW 1

static void
gimp_text_tool_confirm_response (GtkWidget    *widget,
                                 gint          response_id,
                                 GimpTextTool *text_tool)
{
  GimpTextLayer *layer = text_tool->layer;

  gtk_widget_destroy (widget);

  if (layer && layer->text)
    {
      switch (response_id)
        {
        case RESPONSE_NEW:
          gimp_text_tool_create_layer (text_tool, layer->text);
          break;

        case GTK_RESPONSE_OK:
          gimp_text_tool_connect (text_tool, layer, layer->text);
          gimp_text_tool_editor (text_tool);
          break;

        default:
          break;
        }
    }
}

static void
gimp_text_tool_confirm_dialog (GimpTextTool *text_tool)
{
  GimpTool  *tool = GIMP_TOOL (text_tool);
  GtkWidget *dialog;
  GtkWidget *vbox;
  GtkWidget *label;

  g_return_if_fail (text_tool->layer != NULL);

  if (text_tool->confirm_dialog)
    {
      gtk_window_present (GTK_WINDOW (text_tool->confirm_dialog));
      return;
    }

  dialog = gimp_viewable_dialog_new (GIMP_VIEWABLE (text_tool->layer),
                                     _("Confirm Text Editing"),
                                     "gimp-text-tool-confirm",
                                     GIMP_STOCK_TEXT_LAYER,
                                     _("Confirm Text Editing"),
                                     tool->gdisp->shell,
                                     gimp_standard_help_func,
                                     tool->tool_info->help_id,
                                     GTK_STOCK_NEW,    RESPONSE_NEW,
                                     GTK_STOCK_CANCEL, GTK_RESPONSE_CANCEL,
                                     GIMP_STOCK_EDIT,  GTK_RESPONSE_OK,
                                     NULL);

  gtk_window_set_resizable (GTK_WINDOW (dialog), FALSE);

  g_signal_connect (dialog, "response",
                    G_CALLBACK (gimp_text_tool_confirm_response),
                    text_tool);

  vbox = gtk_vbox_new (FALSE, 6);
  gtk_container_set_border_width (GTK_CONTAINER (vbox), 10);
  gtk_box_pack_start (GTK_BOX (GTK_DIALOG (dialog)->vbox),
                      vbox, FALSE, FALSE, 0);
  gtk_widget_show (vbox);

  label = gtk_label_new (_("The layer you selected is a text layer but "
                           "it has been modified using other tools. "
                           "Editing the layer with the text tool will "
                           "discard these modifications."
                           "\n\n"
                           "You can edit the layer or create a new "
                           "text layer from its text attributes."));
  gtk_misc_set_alignment (GTK_MISC (label), 0.0, 0.5);
  gtk_label_set_line_wrap (GTK_LABEL (label), TRUE);
  gtk_box_pack_start (GTK_BOX (vbox), label, FALSE, FALSE, 0);
  gtk_widget_show (label);

  gtk_widget_show (dialog);

  text_tool->confirm_dialog = dialog;
  g_signal_connect_swapped (dialog, "destroy",
                            G_CALLBACK (g_nullify_pointer),
                            &text_tool->confirm_dialog);
}

static void
gimp_text_tool_layer_changed (GimpImage    *image,
                              GimpTextTool *text_tool)
{
  GimpLayer *layer = gimp_image_get_active_layer (image);

  gimp_text_tool_set_drawable (text_tool, GIMP_DRAWABLE (layer), FALSE);
}

static void
gimp_text_tool_set_image (GimpTextTool *text_tool,
                          GimpImage    *image)
{
  if (text_tool->image == image)
    return;

  if (text_tool->image)
    {
      g_signal_handlers_disconnect_by_func (text_tool->image,
                                            gimp_text_tool_layer_changed,
                                            text_tool);

      g_object_remove_weak_pointer (G_OBJECT (text_tool->image),
                                    (gpointer *) &text_tool->image);
      text_tool->image = NULL;
    }

  if (image)
    {
      GimpToolOptions *options;

      text_tool->image = image;
      g_object_add_weak_pointer (G_OBJECT (text_tool->image),
                                 (gpointer *) &text_tool->image);

      g_signal_connect_object (text_tool->image, "active_layer_changed",
                               G_CALLBACK (gimp_text_tool_layer_changed),
                               text_tool, 0);

      options = GIMP_TOOL (text_tool)->tool_info->tool_options;
      gimp_size_entry_set_resolution (GIMP_TEXT_OPTIONS (options)->size_entry,
                                      0, image->yresolution, FALSE);
    }
}

static gboolean
gimp_text_tool_set_drawable (GimpTextTool *text_tool,
                             GimpDrawable *drawable,
                             gboolean      confirm)
{
  GimpImage *image = NULL;

  if (text_tool->confirm_dialog)
    gtk_widget_destroy (text_tool->confirm_dialog);

  if (drawable)
    image = gimp_item_get_image (GIMP_ITEM (drawable));

  gimp_text_tool_set_image (text_tool, image);

  if (drawable && GIMP_IS_LAYER (drawable))
    {
      if (GIMP_IS_TEXT_LAYER (drawable) && GIMP_TEXT_LAYER (drawable)->text)
        {
          GimpTextLayer *layer = GIMP_TEXT_LAYER (drawable);

          if (layer == text_tool->layer && layer->text == text_tool->text)
            return TRUE;

          if (layer->modified)
            {
              if (confirm)
                {
                  gimp_text_tool_connect (text_tool, layer, NULL);
                  gimp_text_tool_confirm_dialog (text_tool);
                  return TRUE;
                }
            }
          else
            {
              gimp_text_tool_connect (text_tool, layer, layer->text);
              return TRUE;
            }
        }
    }

  gimp_text_tool_connect (text_tool, NULL, NULL);
  text_tool->layer = NULL;

  return FALSE;
}

void
gimp_text_tool_set_layer (GimpTextTool *text_tool,
                          GimpLayer    *layer)
{
  g_return_if_fail (GIMP_IS_TEXT_TOOL (text_tool));
  g_return_if_fail (layer == NULL || GIMP_IS_LAYER (layer));

  if (gimp_text_tool_set_drawable (text_tool, GIMP_DRAWABLE (layer), TRUE))
    gimp_text_tool_editor (text_tool);
}