/* The GIMP -- an image manipulation program
 * Copyright (C) 1995 Spencer Kimball and Peter Mattis
 *
 * gimpscanner.c
 * Copyright (C) 2002  Sven Neumann <sven@gimp.org>
 *                     Michael Natterer <mitch@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 <errno.h>
#include <fcntl.h>
#include <stdio.h>
#ifdef HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>

#include <glib-object.h>

#ifdef G_OS_WIN32
#include <io.h>
#endif

#include "libgimpcolor/gimpcolor.h"

#include "gimpconfig.h"
#include "gimpscanner.h"

#include "libgimp/gimpintl.h"


/*  local function prototypes  */

static void   gimp_scanner_message (GScanner *scanner,
                                    gchar    *message,
                                    gboolean  is_error);


/*  public functions  */

GScanner *
gimp_scanner_new (const gchar  *filename,
                  GError      **error)
{
  gint        fd;
  GScanner   *scanner;

  g_return_val_if_fail (filename != NULL, NULL);

  fd = open (filename, O_RDONLY);

  if (fd == -1)
    {
      g_set_error (error,
                   GIMP_CONFIG_ERROR, 
                   (errno == ENOENT ?
                    GIMP_CONFIG_ERROR_OPEN_ENOENT : GIMP_CONFIG_ERROR_OPEN),
                   _("Failed to open file: '%s': %s"),
                   filename, g_strerror (errno));
      return NULL;
    }

  scanner = g_scanner_new (NULL);

  g_scanner_input_file (scanner, fd);

  scanner->user_data   = error;
  scanner->msg_handler = gimp_scanner_message;
  scanner->input_name  = g_strdup (filename);

  scanner->config->cset_identifier_first = ( G_CSET_a_2_z G_CSET_A_2_Z );
  scanner->config->cset_identifier_nth   = ( G_CSET_a_2_z G_CSET_A_2_Z "-_" );

  scanner->config->scan_identifier_1char = TRUE;

  return scanner;
}

void
gimp_scanner_destroy (GScanner *scanner)
{
  g_return_if_fail (scanner != NULL);

  close (scanner->input_fd);
  g_free ((gchar *) scanner->input_name);
  g_scanner_destroy (scanner);
}


gboolean
gimp_scanner_parse_token (GScanner   *scanner,
                          GTokenType  token)
{
  if (g_scanner_peek_next_token (scanner) != token)
    return FALSE;

  g_scanner_get_next_token (scanner);

  return TRUE;
}

gboolean
gimp_scanner_parse_identifier (GScanner    *scanner,
                               const gchar *identifier)
{
  if (g_scanner_peek_next_token (scanner) != G_TOKEN_IDENTIFIER)
    return FALSE;

  g_scanner_get_next_token (scanner);

  if (strcmp (scanner->value.v_identifier, identifier))
    return FALSE;

  return TRUE;
}

gboolean
gimp_scanner_parse_string (GScanner  *scanner,
                           gchar    **dest)
{
  if (g_scanner_peek_next_token (scanner) != G_TOKEN_STRING)
    return FALSE;

  g_scanner_get_next_token (scanner);

  if (*scanner->value.v_string)
    {
      if (! g_utf8_validate (scanner->value.v_string, -1, NULL))
        {
          g_scanner_warn (scanner, _("invalid UTF-8 string"));
          return FALSE;
        }
      
      *dest = g_strdup (scanner->value.v_string);
    }

  return TRUE;
}

gboolean
gimp_scanner_parse_string_no_validate (GScanner  *scanner,
                                       gchar    **dest)
{
  if (g_scanner_peek_next_token (scanner) != G_TOKEN_STRING)
    return FALSE;

  g_scanner_get_next_token (scanner);

  if (*scanner->value.v_string)
    *dest = g_strdup (scanner->value.v_string);

  return TRUE;
}

gboolean
gimp_scanner_parse_int (GScanner *scanner,
                        gint     *dest)
{
  if (g_scanner_peek_next_token (scanner) != G_TOKEN_INT)
    return FALSE;

  g_scanner_get_next_token (scanner);

  *dest = scanner->value.v_int;

  return TRUE;
}

gboolean
gimp_scanner_parse_float (GScanner *scanner,
                          gdouble  *dest)
{
  if (g_scanner_peek_next_token (scanner) != G_TOKEN_FLOAT)
    return FALSE;

  g_scanner_get_next_token (scanner);

  *dest = scanner->value.v_float;

  return TRUE;
}

enum
{
  COLOR_RGB  = 1,
  COLOR_RGBA,
  COLOR_HSV,
  COLOR_HSVA
};

gboolean
gimp_scanner_parse_color (GScanner *scanner,
                          GimpRGB  *dest)
{
  guint      scope_id;
  guint      old_scope_id;
  GTokenType token;
  GimpRGB    color;

  scope_id = g_quark_from_static_string ("gimp_scanner_parse_color");
  old_scope_id = g_scanner_set_scope (scanner, scope_id);

  if (! g_scanner_scope_lookup_symbol (scanner, scope_id, "color-rgb"))
    {
      g_scanner_scope_add_symbol (scanner, scope_id, 
                                  "color-rgb", GINT_TO_POINTER (COLOR_RGB));
      g_scanner_scope_add_symbol (scanner, scope_id, 
                                  "color-rgba", GINT_TO_POINTER (COLOR_RGBA));
      g_scanner_scope_add_symbol (scanner, scope_id, 
                                  "color-hsv", GINT_TO_POINTER (COLOR_HSV));
      g_scanner_scope_add_symbol (scanner, scope_id, 
                                  "color-hsva", GINT_TO_POINTER (COLOR_HSVA));
    }

  token = G_TOKEN_LEFT_PAREN;

  while (g_scanner_peek_next_token (scanner) == token)
    {
      token = g_scanner_get_next_token (scanner);

      switch (token)
        {
        case G_TOKEN_LEFT_PAREN:
          token = G_TOKEN_SYMBOL;
          break;

        case G_TOKEN_SYMBOL:
          {
            gdouble  col[4] = { 0.0, 0.0, 0.0, 1.0 };
            gint     n_channels = 4;
            gboolean is_hsv     = FALSE;
            gint     i;

            switch (GPOINTER_TO_INT (scanner->value.v_symbol))
              {
              case COLOR_RGB:
                n_channels = 3;
                /* fallthrough */
              case COLOR_RGBA:
                break;

              case COLOR_HSV:
                n_channels = 3;
                /* fallthrough */
              case COLOR_HSVA:
                is_hsv = TRUE;
                break;
              }

            token = G_TOKEN_FLOAT;

            for (i = 0; i < n_channels; i++)
              {
                if (! gimp_scanner_parse_float (scanner, &col[i]))
                  goto finish;
              }

            if (is_hsv)
              {
                GimpHSV hsv;

                gimp_hsva_set (&hsv, col[0], col[1], col[2], col[3]);
                gimp_hsv_clamp (&hsv);

                gimp_hsv_to_rgb (&hsv, &color);
              }
            else
              {
                gimp_rgba_set (&color, col[0], col[1], col[2], col[3]);
                gimp_rgb_clamp (&color);
              }
          }
          token = G_TOKEN_RIGHT_PAREN;
          break;

        case G_TOKEN_RIGHT_PAREN:
          token = G_TOKEN_NONE; /* indicates success */
          goto finish;

        default: /* do nothing */
          break;
        }
    }

 finish:

  if (token != G_TOKEN_NONE)
    {
      g_scanner_get_next_token (scanner);
      g_scanner_unexp_token (scanner, token, NULL, NULL, NULL,
                             _("fatal parse error"), TRUE);
    }
  else
    {
      *dest = color;
    }

  g_scanner_set_scope (scanner, old_scope_id);

  return (token == G_TOKEN_NONE);
}

gboolean
gimp_scanner_parse_string_list (GScanner  *scanner,
                                GList    **dest)
{
  GTokenType  token;
  GList      *list = NULL;

  token = G_TOKEN_LEFT_PAREN;

  while (g_scanner_peek_next_token (scanner) == token)
    {
      token = g_scanner_get_next_token (scanner);

      switch (token)
        {
        case G_TOKEN_LEFT_PAREN:
          token = G_TOKEN_STRING;
          break;

        case G_TOKEN_STRING:
          do
            {
              list = g_list_append (list, g_strdup (scanner->value.v_string));

              token = g_scanner_peek_next_token (scanner);
              if (token == G_TOKEN_STRING)
                g_scanner_get_next_token (scanner);
            }
          while (token == G_TOKEN_STRING);
          token = G_TOKEN_RIGHT_PAREN;
          break;

        case G_TOKEN_RIGHT_PAREN:
          token = G_TOKEN_NONE; /* indicates success */
          goto finish;

        default: /* do nothing */
          break;
        }
    }

 finish:

  if (token != G_TOKEN_NONE)
    {
      g_list_foreach (list, (GFunc) g_free, NULL);
      g_list_free (list);
      list = NULL;

      g_scanner_get_next_token (scanner);
      g_scanner_unexp_token (scanner, token, NULL, NULL, NULL,
                             _("fatal parse error"), TRUE);
    }
  else
    {
      *dest = list;
    }

  return (token == G_TOKEN_NONE);
}


/*  private functions  */

static void
gimp_scanner_message (GScanner *scanner,
                      gchar    *message,
                      gboolean  is_error)
{
  GError **error = scanner->user_data;

  /* we don't expect warnings */
  g_return_if_fail (is_error);

  g_set_error (error,
               GIMP_CONFIG_ERROR, GIMP_CONFIG_ERROR_PARSE,
               _("Error while parsing '%s' in line %d:\n%s"), 
               scanner->input_name, scanner->line, message);
}