/*

 * Copyright (C) 2011 Colin Walters <walters@verbum.org>

 *

 * SPDX-License-Identifier: LGPL-2.0+

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the

 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,

 * Boston, MA 02111-1307, USA.

 *

 * Author: Colin Walters <walters@verbum.org>

 */

#include "config.h"

#include <gio/gio.h>

#include <gio/gfiledescriptorbased.h>

#include <string.h>

#include "otutil.h"

/* Create a new GVariant empty GVariant of type a{sv} */

GVariant *

ot_gvariant_new_empty_string_dict (void)

{

  g_auto(GVariantBuilder) builder = OT_VARIANT_BUILDER_INITIALIZER;

  g_variant_builder_init (&builder, G_VARIANT_TYPE ("a{sv}"));

  return g_variant_builder_end (&builder);

}

/* Create a new GVariant of type ay from the raw @data pointer */

GVariant *

ot_gvariant_new_bytearray (const guchar   *data,

                           gsize           len)

{

  gpointer data_copy = g_memdup (data, len);

  GVariant *ret = g_variant_new_from_data (G_VARIANT_TYPE ("ay"), data_copy,

                                 len, FALSE, g_free, data_copy);

  return ret;

}

/* Convert a GBytes into a GVariant of type ay (byte array) */

GVariant *

ot_gvariant_new_ay_bytes (GBytes *bytes)

{

  gsize size;

  gconstpointer data = g_bytes_get_data (bytes, &size);

  g_bytes_ref (bytes);

  return g_variant_new_from_data (G_VARIANT_TYPE ("ay"), data, size,

                                  TRUE, (GDestroyNotify)g_bytes_unref, bytes);

}

/* Create a GVariant in @out_variant that is backed by

 * the data from @fd, starting at @start.  If the data is

 * large enough, mmap() may be used.  @trusted is used

 * by the GVariant core; see g_variant_new_from_data().

 */

gboolean

ot_variant_read_fd (int                    fd,

                    goffset                start,

                    const GVariantType    *type,

                    gboolean               trusted,

                    GVariant             **out_variant,

                    GError               **error)

{

  g_autoptr(GBytes) bytes = ot_fd_readall_or_mmap (fd, start, error);

  if (!bytes)

    return FALSE;

  *out_variant = g_variant_ref_sink (g_variant_new_from_bytes (type, bytes, trusted));

  return TRUE;

}

/* GVariants are immutable; this function allows generating an open builder

 * for a new variant, inherting the data from @variant.

 */

GVariantBuilder *

ot_util_variant_builder_from_variant (GVariant            *variant,

                                      const GVariantType  *type)

{

  GVariantBuilder *builder = g_variant_builder_new (type);

  if (variant != NULL)

    {

      const int n = g_variant_n_children (variant);

      for (int i = 0; i < n; i++)

        {

          g_autoptr(GVariant) child = g_variant_get_child_value (variant, i);

          g_variant_builder_add_value (builder, child);

        }

    }

  return builder;

}

/**

 * ot_variant_bsearch_str:

 * @array: A GVariant array whose first element must be a string

 * @str: Search for this string

 * @out_pos: Output position

 *

 *

 * Binary search in a GVariant array, which must be of the form 'a(s...)',

 * where '...' may be anything.  The array elements must be sorted.

 *

 * Returns: %TRUE if found, %FALSE otherwise

 */

gboolean

ot_variant_bsearch_str (GVariant   *array,

                        const char *str,

                        int        *out_pos)

{

  const gsize n = g_variant_n_children (array);

  if (n == 0)

    return FALSE;

  gsize imax = n - 1;

  gsize imin = 0;

  gsize imid = -1;

  while (imax >= imin)

    {

      const char *cur;

      imid = (imin + imax) / 2;

      g_autoptr(GVariant) child = g_variant_get_child_value (array, imid);

      g_variant_get_child (child, 0, "&s", &cur, NULL);

      int cmp = strcmp (cur, str);

      if (cmp < 0)

        imin = imid + 1;

      else if (cmp > 0)

        {

          if (imid == 0)

            break;

          imax = imid - 1;

        }

      else

        {

          *out_pos = imid;

          return TRUE;

        }

    }

  *out_pos = imid;

  return FALSE;

}