/*

 * filetransfer.c

 *

 * Copyrigth (C) 2010 Nicolas Cornu <nicolas.cornu@ensi-bourges.fr>

 *

 * 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 <glib.h>

#include <string.h>

#include <mcabber/modules.h>

#include <mcabber/utils.h>

#include <mcabber/xmpp_helper.h>

#include <mcabber/settings.h>

#include <mcabber/logprint.h>

#include <jingle/jingle.h>

#include <jingle/check.h>

#include <jingle/register.h>

#include "filetransfer.h"

gconstpointer jingle_ft_check(JingleContent *cn, GError **err);

static gboolean is_md5_hash(const gchar *hash);

static void jingle_ft_init(void);

static void jingle_ft_uninit(void);

const gchar *deps[] = { "jingle", NULL };

module_info_t info_jingle_filetransfer = {

  .branch          = MCABBER_BRANCH,

  .api             = MCABBER_API_VERSION,

  .version         = PROJECT_VERSION,

  .description     = "Jingle File Transfer (XEP-0234)\n",

  .requires        = deps,

  .init            = jingle_ft_init,

  .uninit          = jingle_ft_uninit,

  .next            = NULL,

};

gconstpointer jingle_ft_check(JingleContent *cn, GError **err)

{

  JingleFT *ft = NULL;

  LmMessageNode *node;

  const gchar *datestr, *sizestr;

  node = lm_message_node_get_child(cn->description, "offer");

  if (!node) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_MISSING,

                "the offer element is missing");

    return NULL;

  }

  node = lm_message_node_get_child(node, "file");

  if (!node) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_MISSING,

                "the file element is missing");

    return NULL;

  }

  if (g_strcmp0(lm_message_node_get_attribute(node, "xmlns"), NS_SI_FT)) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_MISSING,

                "the file transfer offer has an invalid/unsupported namespace");

    return NULL;

  }

  ft = g_new0(JingleFT, 1);

  datestr  = lm_message_node_get_attribute(node, "date");

  ft->hash = (gchar *) lm_message_node_get_attribute(node, "hash");

  ft->name = (gchar *) lm_message_node_get_attribute(node, "name");

  sizestr  = lm_message_node_get_attribute(node, "size");

  if (!ft->name || !sizestr) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_MISSING,

                "an attribute of the file element is missing");

    g_free(ft);

    return NULL;

  }

  ft->date = from_iso8601(datestr, 1);

  ft->size = g_ascii_strtoll(sizestr, NULL, 10);

  // the size attribute is a xs:integer an therefore can be negative.

  if (ft->size < 0) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_BADVALUE,

                "the offered file has a negative size");

    g_free(ft);

    return NULL;

  }

  ft->name = g_path_get_basename(ft->name);

  if (settings_opt_get("jingle_ft_dir") != NULL)

    ft->name = g_build_filename(settings_opt_get("jingle_ft_dir"), ft->name, NULL);

  else

    ft->name = g_build_filename("/tmp", ft->name, NULL);

  if (!g_strcmp0(ft->name, ".")) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_BADVALUE,

                "the offered file has an invalid filename");

    g_free(ft->name);

    g_free(ft);

    return NULL;

  }

  // check if the md5 hash is valid ([a-fA-F0-9){32})

  if (ft->hash != NULL && (strlen(ft->hash) != 32 || !is_md5_hash(ft->hash))) {

    g_set_error(err, JINGLE_CHECK_ERROR, JINGLE_CHECK_ERROR_BADVALUE,

                "the offered file has an invalid filename");

    g_free(ft->name);

    g_free(ft);

    return NULL;

  }

  ft->hash = g_strndup(ft->hash, 32);

  return (gconstpointer) ft;

}

  int i = 0;

  for (i = 0; i < 32 && hash[i]; i++)

    if (!g_ascii_isxdigit(hash[i])) break;

  if (i == 32)

    return TRUE;

  else

    return FALSE;

}

gboolean handle_data(gconstpointer jingleft, const gchar *data, guint len)

{

  JingleFT *ft = (JingleFT *) jingleft;

  GError *err = NULL;

  GIOStatus status;

  gsize bytes_written = 0;

  // TODO: check if the file already exist or if it was created

  // during the call to jingle_ft_check and handle_data

  if (ft->outfile == NULL) {

    ft->outfile = g_io_channel_new_file(ft->name, "w", &err);

    if (ft->outfile == NULL || err != NULL) {

      // propagate the GError ?

      return FALSE;

	}

  }

  status = g_io_channel_write_chars(ft->outfile, data, (gssize) len,

                                    &bytes_written, &err);

  if (status != G_IO_STATUS_NORMAL || err != NULL) {

    return FALSE;

  }

  if (bytes_written != len) {

    // not supposed to happen if status is normal, unless outfile is non-blocking

    return FALSE;

  }

  return TRUE;

}

static void jingle_ft_init(void)

{

  jingle_register_app(NS_JINGLE_APP_FT, &funcs, JINGLE_TRANS_TCP);

  xmpp_add_feature(NS_JINGLE_APP_FT);

}

static void jingle_ft_uninit(void)

{

  xmpp_del_feature(NS_JINGLE_APP_FT);

  jingle_unregister_app(NS_JINGLE_APP_FT);

}