/*
     This file is part of GNUnet.
     (C) 2001, 2002, 2004, 2005, 2006, 2007, 2009 Christian Grothoff (and other contributing authors)

     GNUnet 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 3, 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
     General Public License for more details.

     You should have received a copy of the GNU General Public License
     along with GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/
/**
 * @file fs/gnunet-download.c
 * @brief downloading 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 int verbose;

static int delete_incomplete;

static const struct GNUNET_CONFIGURATION_Handle *cfg;

static struct GNUNET_FS_Handle *ctx;

static struct GNUNET_FS_DownloadContext *dc;

static unsigned int anonymity = 1;

static unsigned int parallelism = 16;

static unsigned int request_parallelism = 4092;

static int do_recursive;

static char *filename;

static int local_only;

static void
cleanup_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  GNUNET_FS_stop (ctx);
  ctx = NULL;
}


static void
shutdown_task (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
{
  struct GNUNET_FS_DownloadContext *d;

  if (dc != NULL)
  {
    d = dc;
    dc = NULL;
    GNUNET_FS_download_stop (d, delete_incomplete);
  }
}


/**
 * 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)
{
  char *s;
  char *s2;
  char *t;

  switch (info->status)
  {
  case GNUNET_FS_STATUS_DOWNLOAD_START:
    if (verbose > 1)
      FPRINTF (stderr, _("Starting download `%s'.\n"),
               info->value.download.filename);
    break;
  case GNUNET_FS_STATUS_DOWNLOAD_PROGRESS:
    if (verbose)
    {
      s = GNUNET_STRINGS_relative_time_to_string (info->value.download.eta);
      if (info->value.download.specifics.progress.block_download_duration.rel_value 
          == GNUNET_TIME_UNIT_FOREVER_REL.rel_value)
        s2 = GNUNET_strdup (_("<unknown time>"));
      else
        s2 = GNUNET_STRINGS_relative_time_to_string (
              info->value.download.specifics.progress.block_download_duration);
      t = GNUNET_STRINGS_byte_size_fancy (info->value.download.completed *
                                          1000LL /
                                          (info->value.download.
                                           duration.rel_value + 1));
      FPRINTF (stdout,
               _("Downloading `%s' at %llu/%llu (%s remaining, %s/s). Block took %s to download\n"),
               info->value.download.filename,
               (unsigned long long) info->value.download.completed,
               (unsigned long long) info->value.download.size, s, t, s2);
      GNUNET_free (s);
      GNUNET_free (s2);
      GNUNET_free (t);
    }
    break;
  case GNUNET_FS_STATUS_DOWNLOAD_ERROR:
    FPRINTF (stderr, _("Error downloading: %s.\n"),
             info->value.download.specifics.error.message);
    GNUNET_SCHEDULER_shutdown ();
    break;
  case GNUNET_FS_STATUS_DOWNLOAD_COMPLETED:
    s = GNUNET_STRINGS_byte_size_fancy (info->value.download.completed * 1000 /
                                        (info->value.download.
                                         duration.rel_value + 1));
    FPRINTF (stdout, _("Downloading `%s' done (%s/s).\n"),
             info->value.download.filename, s);
    GNUNET_free (s);
    if (info->value.download.dc == dc)
      GNUNET_SCHEDULER_shutdown ();
    break;
  case GNUNET_FS_STATUS_DOWNLOAD_STOPPED:
    if (info->value.download.dc == dc)
      GNUNET_SCHEDULER_add_continuation (&cleanup_task, NULL,
                                         GNUNET_SCHEDULER_REASON_PREREQ_DONE);
    break;
  case GNUNET_FS_STATUS_DOWNLOAD_ACTIVE:
  case GNUNET_FS_STATUS_DOWNLOAD_INACTIVE:
    break;
  default:
    FPRINTF (stderr, _("Unexpected status: %d\n"), info->status);
    break;
  }
  return NULL;
}


/**
 * 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;
  char *emsg;
  enum GNUNET_FS_DownloadOptions options;

  if (NULL == args[0])
  {
    FPRINTF (stderr, "%s",  _("You need to specify a URI argument.\n"));
    return;
  }
  uri = GNUNET_FS_uri_parse (args[0], &emsg);
  if (NULL == uri)
  {
    FPRINTF (stderr, _("Failed to parse URI: %s\n"), emsg);
    GNUNET_free (emsg);
    ret = 1;
    return;
  }
  if ((!GNUNET_FS_uri_test_chk (uri)) && (!GNUNET_FS_uri_test_loc (uri)))
  {
    FPRINTF (stderr, "%s",  _("Only CHK or LOC URIs supported.\n"));
    ret = 1;
    GNUNET_FS_uri_destroy (uri);
    return;
  }
  if (NULL == filename)
  {
    FPRINTF (stderr, "%s",  _("Target filename must be specified.\n"));
    ret = 1;
    GNUNET_FS_uri_destroy (uri);
    return;
  }
  cfg = c;
  ctx =
      GNUNET_FS_start (cfg, "gnunet-download", &progress_cb, NULL,
                       GNUNET_FS_FLAGS_NONE,
                       GNUNET_FS_OPTIONS_DOWNLOAD_PARALLELISM, parallelism,
                       GNUNET_FS_OPTIONS_REQUEST_PARALLELISM,
                       request_parallelism, GNUNET_FS_OPTIONS_END);
  if (NULL == ctx)
  {
    FPRINTF (stderr, _("Could not initialize `%s' subsystem.\n"), "FS");
    GNUNET_FS_uri_destroy (uri);
    ret = 1;
    return;
  }
  options = GNUNET_FS_DOWNLOAD_OPTION_NONE;
  if (do_recursive)
    options |= GNUNET_FS_DOWNLOAD_OPTION_RECURSIVE;
  if (local_only)
    options |= GNUNET_FS_DOWNLOAD_OPTION_LOOPBACK_ONLY;
  dc = GNUNET_FS_download_start (ctx, uri, NULL, filename, NULL, 0,
                                 GNUNET_FS_uri_chk_get_file_size (uri),
                                 anonymity, options, NULL, NULL);
  GNUNET_FS_uri_destroy (uri);
  if (dc == NULL)
  {
    GNUNET_FS_stop (ctx);
    ctx = NULL;
    return;
  }
  GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_FOREVER_REL, &shutdown_task,
                                NULL);
}


/**
 * The main function to download 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)
{
  static const struct GNUNET_GETOPT_CommandLineOption options[] = {
    {'a', "anonymity", "LEVEL",
     gettext_noop ("set the desired LEVEL of receiver-anonymity"),
     1, &GNUNET_GETOPT_set_uint, &anonymity},
    {'D', "delete-incomplete", NULL,
     gettext_noop ("delete incomplete downloads (when aborted with CTRL-C)"),
     0, &GNUNET_GETOPT_set_one, &delete_incomplete},
    {'n', "no-network", NULL,
     gettext_noop ("only search the local peer (no P2P network search)"),
     0, &GNUNET_GETOPT_set_uint, &local_only},
    {'o', "output", "FILENAME",
     gettext_noop ("write the file to FILENAME"),
     1, &GNUNET_GETOPT_set_string, &filename},
    {'p', "parallelism", "DOWNLOADS",
     gettext_noop
     ("set the maximum number of parallel downloads that is allowed"),
     1, &GNUNET_GETOPT_set_uint, &parallelism},
    {'r', "request-parallelism", "REQUESTS",
     gettext_noop
     ("set the maximum number of parallel requests for blocks that is allowed"),
     1, &GNUNET_GETOPT_set_uint, &request_parallelism},
    {'R', "recursive", NULL,
     gettext_noop ("download a GNUnet directory recursively"),
     0, &GNUNET_GETOPT_set_one, &do_recursive},
    {'V', "verbose", NULL,
     gettext_noop ("be verbose (print progress information)"),
     0, &GNUNET_GETOPT_increment_value, &verbose},
    GNUNET_GETOPT_OPTION_END
  };
  return (GNUNET_OK ==
          GNUNET_PROGRAM_run (argc, argv, "gnunet-download [OPTIONS] URI",
                              gettext_noop
                              ("Download files from GNUnet using a GNUnet CHK or LOC URI (gnunet://fs/chk/...)"),
                              options, &run, NULL)) ? ret : 1;
}

/* end of gnunet-download.c */