/*
     This file is part of GNUnet.
     Copyright (C) 2001, 2002, 2004, 2005, 2006, 2007, 2009 GNUnet e.V.

     GNUnet is free software: you can redistribute it and/or modify it
     under the terms of the GNU Affero General Public License as published
     by the Free Software Foundation, either version 3 of the License,
     or (at your option) any later version.

     GNUnet 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
     Affero General Public License for more details.

     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.

     SPDX-License-Identifier: AGPL3.0-or-later
 */
/**
 * @file fs/gnunet-search.c
 * @brief searching for files on GNUnet
 * @author Christian Grothoff
 * @author Krista Bennett
 * @author James Blackwell
 * @author Igor Wronsky
 */
#include "platform.h"
#include "gnunet_fs_service.h"

static int ret;

static const struct GNUNET_CONFIGURATION_Handle *cfg;

static struct GNUNET_FS_Handle *ctx;

static struct GNUNET_FS_SearchContext *sc;

static char *output_filename;

static struct GNUNET_FS_DirectoryBuilder *db;

static unsigned int anonymity = 1;

/**
 * Timeout for the search, 0 means to wait for CTRL-C.
 */
static struct GNUNET_TIME_Relative timeout;

static unsigned int results_limit;

static unsigned int results;

static unsigned int verbose;

static int local_only;

static struct GNUNET_SCHEDULER_Task *tt;


/**
 * Type of a function that libextractor calls for each
 * meta data item found.
 *
 * @param cls closure (user-defined, unused)
 * @param plugin_name name of the plugin that produced this value;
 *        special values can be used (i.e. '&lt;zlib&gt;' for zlib being
 *        used in the main libextractor library and yielding
 *        meta data).
 * @param type libextractor-type describing the meta data
 * @param format basic format information about data
 * @param data_mime_type mime-type of data (not of the original file);
 *        can be NULL (if mime-type is not known)
 * @param data actual meta-data found
 * @param data_size number of bytes in @a data
 * @return 0 to continue extracting, 1 to abort
 */
static int
item_printer (void *cls,
              const char *plugin_name,
              enum EXTRACTOR_MetaType type,
              enum EXTRACTOR_MetaFormat format,
              const char *data_mime_type,
              const char *data,
              size_t data_size)
{
  if ((format != EXTRACTOR_METAFORMAT_UTF8) &&
      (format != EXTRACTOR_METAFORMAT_C_STRING))
    return 0;
  if (type == EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME)
    return 0;
#if HAVE_LIBEXTRACTOR
  printf ("\t%20s: %s\n",
          dgettext (LIBEXTRACTOR_GETTEXT_DOMAIN,
                    EXTRACTOR_metatype_to_string (type)),
          data);
#else
  printf ("\t%20d: %s\n", type, data);
#endif
  return 0;
}


static void
clean_task (void *cls)
{
  size_t dsize;
  void *ddata;

  GNUNET_FS_stop (ctx);
  ctx = NULL;
  if (output_filename == NULL)
    return;
  if (GNUNET_OK != GNUNET_FS_directory_builder_finish (db, &dsize, &ddata))
  {
    GNUNET_break (0);
    GNUNET_free (output_filename);
    return;
  }
  if (dsize != GNUNET_DISK_fn_write (output_filename,
                                     ddata,
                                     dsize,
                                     GNUNET_DISK_PERM_USER_READ
                                     | GNUNET_DISK_PERM_USER_WRITE))
  {
    fprintf (stderr,
             _ ("Failed to write directory with search results to `%s'\n"),
             output_filename);
  }
  GNUNET_free_non_null (ddata);
  GNUNET_free (output_filename);
}


/**
 * Called by FS client to give information about the progress of an
 * operation.
 *
 * @param cls closure
 * @param info details about the event, specifying the event type
 *        and various bits about the event
 * @return client-context (for the next progress call
 *         for this operation; should be set to NULL for
 *         SUSPEND and STOPPED events).  The value returned
 *         will be passed to future callbacks in the respective
 *         field in the GNUNET_FS_ProgressInfo struct.
 */
static void *
progress_cb (void *cls, const struct GNUNET_FS_ProgressInfo *info)
{
  static unsigned int cnt;
  int is_directory;
  char *uri;
  char *filename;

  switch (info->status)
  {
  case GNUNET_FS_STATUS_SEARCH_START:
    break;

  case GNUNET_FS_STATUS_SEARCH_RESULT:
    if (db != NULL)
      GNUNET_FS_directory_builder_add (db,
                                       info->value.search.specifics.result.uri,
                                       info->value.search.specifics.result.meta,
                                       NULL);
    uri = GNUNET_FS_uri_to_string (info->value.search.specifics.result.uri);
    printf ("#%u:\n", ++cnt);
    filename = GNUNET_CONTAINER_meta_data_get_by_type (
      info->value.search.specifics.result.meta,
      EXTRACTOR_METATYPE_GNUNET_ORIGINAL_FILENAME);
    is_directory = GNUNET_FS_meta_data_test_for_directory (
      info->value.search.specifics.result.meta);
    if (NULL != filename)
    {
      while ((filename[0] != '\0') && ('/' == filename[strlen (filename) - 1]))
        filename[strlen (filename) - 1] = '\0';
      GNUNET_DISK_filename_canonicalize (filename);
      if (GNUNET_YES == is_directory)
        printf ("gnunet-download -o \"%s%s\" -R %s\n",
                filename,
                GNUNET_FS_DIRECTORY_EXT,
                uri);
      else
        printf ("gnunet-download -o \"%s\" %s\n", filename, uri);
    }
    else if (GNUNET_YES == is_directory)
      printf ("gnunet-download -o \"collection%s\" -R %s\n",
              GNUNET_FS_DIRECTORY_EXT,
              uri);
    else
      printf ("gnunet-download %s\n", uri);
    if (verbose)
      GNUNET_CONTAINER_meta_data_iterate (info->value.search.specifics.result
                                          .meta,
                                          &item_printer,
                                          NULL);
    printf ("\n");
    fflush (stdout);
    GNUNET_free_non_null (filename);
    GNUNET_free (uri);
    results++;
    if ((results_limit > 0) && (results >= results_limit))
      GNUNET_SCHEDULER_shutdown ();
    break;

  case GNUNET_FS_STATUS_SEARCH_UPDATE:
    break;

  case GNUNET_FS_STATUS_SEARCH_RESULT_STOPPED:
    /* ignore */
    break;

  case GNUNET_FS_STATUS_SEARCH_ERROR:
    fprintf (stderr,
             _ ("Error searching: %s.\n"),
             info->value.search.specifics.error.message);
    GNUNET_SCHEDULER_shutdown ();
    break;

  case GNUNET_FS_STATUS_SEARCH_STOPPED:
    GNUNET_SCHEDULER_add_now (&clean_task, NULL);
    break;

  default:
    fprintf (stderr, _ ("Unexpected status: %d\n"), info->status);
    break;
  }
  return NULL;
}


static void
shutdown_task (void *cls)
{
  if (sc != NULL)
  {
    GNUNET_FS_search_stop (sc);
    sc = NULL;
  }
}


static void
timeout_task (void *cls)
{
  tt = NULL;
  GNUNET_SCHEDULER_shutdown ();
}


/**
 * Main function that will be run by the scheduler.
 *
 * @param cls closure
 * @param args remaining command-line arguments
 * @param cfgfile name of the configuration file used (for saving, can be NULL!)
 * @param c configuration
 */
static void
run (void *cls,
     char *const *args,
     const char *cfgfile,
     const struct GNUNET_CONFIGURATION_Handle *c)
{
  struct GNUNET_FS_Uri *uri;
  unsigned int argc;
  enum GNUNET_FS_SearchOptions options;

  argc = 0;
  while (NULL != args[argc])
    argc++;
  uri = GNUNET_FS_uri_ksk_create_from_args (argc, (const char **) args);
  if (NULL == uri)
  {
    fprintf (stderr,
             "%s",
             _ ("Could not create keyword URI from arguments.\n"));
    ret = 1;
    return;
  }
  cfg = c;
  ctx = GNUNET_FS_start (cfg,
                         "gnunet-search",
                         &progress_cb,
                         NULL,
                         GNUNET_FS_FLAGS_NONE,
                         GNUNET_FS_OPTIONS_END);
  if (NULL == ctx)
  {
    fprintf (stderr, _ ("Could not initialize `%s' subsystem.\n"), "FS");
    GNUNET_FS_uri_destroy (uri);
    ret = 1;
    return;
  }
  if (output_filename != NULL)
    db = GNUNET_FS_directory_builder_create (NULL);
  options = GNUNET_FS_SEARCH_OPTION_NONE;
  if (local_only)
    options |= GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY;
  sc = GNUNET_FS_search_start (ctx, uri, anonymity, options, NULL);
  GNUNET_FS_uri_destroy (uri);
  if (NULL == sc)
  {
    fprintf (stderr, "%s", _ ("Could not start searching.\n"));
    GNUNET_FS_stop (ctx);
    ret = 1;
    return;
  }
  if (0 != timeout.rel_value_us)
    tt = GNUNET_SCHEDULER_add_delayed (timeout, &timeout_task, NULL);
  GNUNET_SCHEDULER_add_shutdown (&shutdown_task, NULL);
}


/**
 * The main function to search GNUnet.
 *
 * @param argc number of arguments from the command line
 * @param argv command line arguments
 * @return 0 ok, 1 on error
 */
int
main (int argc, char *const *argv)
{
  struct GNUNET_GETOPT_CommandLineOption options[] =
  { GNUNET_GETOPT_option_uint ('a',
                               "anonymity",
                               "LEVEL",
                               gettext_noop (
                                 "set the desired LEVEL of receiver-anonymity"),
                               &anonymity),
    GNUNET_GETOPT_option_flag (
      'n',
      "no-network",
      gettext_noop ("only search the local peer (no P2P network search)"),
      &local_only),
    GNUNET_GETOPT_option_string (
      'o',
      "output",
      "PREFIX",
      gettext_noop ("write search results to file starting with PREFIX"),
      &output_filename),
    GNUNET_GETOPT_option_relative_time (
      't',
      "timeout",
      "DELAY",
      gettext_noop ("automatically terminate search after DELAY"),
      &timeout),
    GNUNET_GETOPT_option_verbose (&verbose),
    GNUNET_GETOPT_option_uint ('N',
                               "results",
                               "VALUE",
                               gettext_noop ("automatically terminate search "
                                             "after VALUE results are found"),
                               &results_limit),
    GNUNET_GETOPT_OPTION_END };

  if (GNUNET_OK != GNUNET_STRINGS_get_utf8_args (argc, argv, &argc, &argv))
    return 2;

  ret =
    (GNUNET_OK ==
     GNUNET_PROGRAM_run (argc,
                         argv,
                         "gnunet-search [OPTIONS] KEYWORD",
                         gettext_noop (
                           "Search GNUnet for files that were published on GNUnet"),
                         options,
                         &run,
                         NULL))
    ? ret
    : 1;
  GNUNET_free_nz ((void *) argv);
  return ret;
}


/* end of gnunet-search.c */