/*
 * This file Copyright (C) 2008-2014 Mnemosyne LLC
 *
 * It may be used under the GNU GPL versions 2 or 3
 * or any future license endorsed by Mnemosyne LLC.
 *
 * $Id$
 */

#include <assert.h>
#include <ctype.h> /* isdigit */
#include <errno.h>
#include <stdlib.h> /* strtol */
#include <string.h> /* strcmp */

#include <zlib.h>

#include <event2/buffer.h>

#include "transmission.h"
#include "completion.h"
#include "crypto-utils.h"
#include "error.h"
#include "fdlimit.h"
#include "file.h"
#include "log.h"
#include "platform-quota.h" /* tr_device_info_get_free_space() */
#include "rpcimpl.h"
#include "session.h"
#include "torrent.h"
#include "utils.h"
#include "variant.h"
#include "version.h"
#include "web.h"

#define RPC_VERSION     15
#define RPC_VERSION_MIN 1

#define RECENTLY_ACTIVE_SECONDS 60

#define TR_N_ELEMENTS(ary)(sizeof (ary) / sizeof (*ary))

#if 0
#define dbgmsg(fmt, ...) \
    do { \
        fprintf (stderr, "%s:%d"#fmt, __FILE__, __LINE__, __VA_ARGS__); \
        fprintf (stderr, "\n"); \
    } while (0)
#else
#define dbgmsg(...) \
  do \
    { \
      if (tr_logGetDeepEnabled ()) \
        tr_logAddDeep (__FILE__, __LINE__, "RPC", __VA_ARGS__); \
    } \
  while (0)
#endif


/***
****
***/

static tr_rpc_callback_status
notify (tr_session * session,
        int          type,
        tr_torrent * tor)
{
    tr_rpc_callback_status status = 0;

    if (session->rpc_func)
        status = session->rpc_func (session, type, tor,
                                    session->rpc_func_user_data);

    return status;
}

/***
****
***/

/* For functions that can't be immediately executed, like torrentAdd,
 * this is the callback data used to pass a response to the caller
 * when the task is complete */
struct tr_rpc_idle_data
{
 tr_session            * session;
 tr_variant            * response;
 tr_variant            * args_out;
 tr_rpc_response_func    callback;
 void                  * callback_user_data;
};

static void
tr_idle_function_done (struct tr_rpc_idle_data * data, const char * result)
{
 struct evbuffer * buf;

 if (result == NULL)
   result = "success";
 tr_variantDictAddStr (data->response, TR_KEY_result, result);

 buf = tr_variantToBuf (data->response, TR_VARIANT_FMT_JSON_LEAN);
 (*data->callback)(data->session, buf, data->callback_user_data);
 evbuffer_free (buf);

 tr_variantFree (data->response);
 tr_free (data->response);
 tr_free (data);
}

/***
****
***/

static tr_torrent **
getTorrents (tr_session * session,
             tr_variant * args,
             int        * setmeCount)
{
  int torrentCount = 0;
  int64_t id;
  tr_torrent ** torrents = NULL;
  tr_variant * ids;
  const char * str;

  if (tr_variantDictFindList (args, TR_KEY_ids, &ids))
    {
      int i;
      const int n = tr_variantListSize (ids);

      torrents = tr_new0 (tr_torrent *, n);

      for (i=0; i<n; ++i)
        {
          const char * str;
          tr_torrent * tor;
          tr_variant * node = tr_variantListChild (ids, i);

          if (tr_variantGetInt (node, &id))
            tor = tr_torrentFindFromId (session, id);
          else if (tr_variantGetStr (node, &str, NULL))
            tor = tr_torrentFindFromHashString (session, str);
          else
            tor = NULL;

          if (tor != NULL)
            torrents[torrentCount++] = tor;
        }
    }
  else if (tr_variantDictFindInt (args, TR_KEY_ids, &id)
        || tr_variantDictFindInt (args, TR_KEY_id, &id))
    {
      tr_torrent * tor;
      torrents = tr_new0 (tr_torrent *, 1);
      if ((tor = tr_torrentFindFromId (session, id)))
        torrents[torrentCount++] = tor;
    }
  else if (tr_variantDictFindStr (args, TR_KEY_ids, &str, NULL))
    {
      if (!strcmp (str, "recently-active"))
        {
          tr_torrent * tor = NULL;
          const time_t now = tr_time ();
          const time_t window = RECENTLY_ACTIVE_SECONDS;
          const int n = tr_sessionCountTorrents (session);
          torrents = tr_new0 (tr_torrent *, n);
          while ((tor = tr_torrentNext (session, tor)))
            if (tor->anyDate >= now - window)
              torrents[torrentCount++] = tor;
        }
      else
        {
          tr_torrent * tor;
          torrents = tr_new0 (tr_torrent *, 1);
          if ((tor = tr_torrentFindFromHashString (session, str)))
            torrents[torrentCount++] = tor;
        }
    }
  else /* all of them */
    {
      torrents = tr_sessionGetTorrents (session, &torrentCount);
    }

  *setmeCount = torrentCount;
  return torrents;
}

static void
notifyBatchQueueChange (tr_session * session, tr_torrent ** torrents, int n)
{
  int i;
  for (i=0; i<n; ++i)
    notify (session, TR_RPC_TORRENT_CHANGED, torrents[i]);
  notify (session, TR_RPC_SESSION_QUEUE_POSITIONS_CHANGED, NULL);
}

static const char*
queueMoveTop (tr_session               * session,
              tr_variant               * args_in,
              tr_variant               * args_out UNUSED,
              struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int n;
  tr_torrent ** torrents = getTorrents (session, args_in, &n);
  tr_torrentsQueueMoveTop (torrents, n);
  notifyBatchQueueChange (session, torrents, n);
  tr_free (torrents);
  return NULL;
}

static const char*
queueMoveUp (tr_session               * session,
             tr_variant               * args_in,
             tr_variant               * args_out UNUSED,
             struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int n;
  tr_torrent ** torrents = getTorrents (session, args_in, &n);
  tr_torrentsQueueMoveUp (torrents, n);
  notifyBatchQueueChange (session, torrents, n);
  tr_free (torrents);
  return NULL;
}

static const char*
queueMoveDown (tr_session               * session,
               tr_variant               * args_in,
               tr_variant               * args_out UNUSED,
               struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int n;
  tr_torrent ** torrents = getTorrents (session, args_in, &n);
  tr_torrentsQueueMoveDown (torrents, n);
  notifyBatchQueueChange (session, torrents, n);
  tr_free (torrents);
  return NULL;
}

static const char*
queueMoveBottom (tr_session               * session,
                 tr_variant               * args_in,
                 tr_variant               * args_out UNUSED,
                 struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int n;
  tr_torrent ** torrents = getTorrents (session, args_in, &n);
  tr_torrentsQueueMoveBottom (torrents, n);
  notifyBatchQueueChange (session, torrents, n);
  tr_free (torrents);
  return NULL;
}

static int
compareTorrentByQueuePosition (const void * va, const void * vb)
{
  const tr_torrent * a = * (const tr_torrent **) va;
  const tr_torrent * b = * (const tr_torrent **) vb;

  return a->queuePosition - b->queuePosition;
}

static const char*
torrentStart (tr_session               * session,
              tr_variant               * args_in,
              tr_variant               * args_out UNUSED,
              struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);
  qsort (torrents, torrentCount, sizeof (tr_torrent *), compareTorrentByQueuePosition);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];
      if (!tor->isRunning)
        {
          tr_torrentStart (tor);
          notify (session, TR_RPC_TORRENT_STARTED, tor);
        }
    }

  tr_free (torrents);
  return NULL;
}

static const char*
torrentStartNow (tr_session               * session,
                 tr_variant               * args_in,
                 tr_variant               * args_out UNUSED,
                 struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);
  qsort (torrents, torrentCount, sizeof (tr_torrent *), compareTorrentByQueuePosition);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];

      if (!tor->isRunning)
        {
          tr_torrentStartNow (tor);
          notify (session, TR_RPC_TORRENT_STARTED, tor);
        }
    }

  tr_free (torrents);
  return NULL;
}

static const char*
torrentStop (tr_session               * session,
             tr_variant               * args_in,
             tr_variant               * args_out UNUSED,
             struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];

      if (tor->isRunning || tr_torrentIsQueued (tor))
        {
          tor->isStopping = true;
          notify (session, TR_RPC_TORRENT_STOPPED, tor);
        }
    }

  tr_free (torrents);
  return NULL;
}

static const char*
torrentRemove (tr_session               * session,
               tr_variant               * args_in,
               tr_variant               * args_out UNUSED,
               struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_rpc_callback_type type;
  bool deleteFlag;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  if (!tr_variantDictFindBool (args_in, TR_KEY_delete_local_data, &deleteFlag))
    deleteFlag = false;
  type = deleteFlag ? TR_RPC_TORRENT_TRASHING
                    : TR_RPC_TORRENT_REMOVING;

  torrents = getTorrents (session, args_in, &torrentCount);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];
      const tr_rpc_callback_status status = notify (session, type, tor);

      if (!(status & TR_RPC_NOREMOVE))
        tr_torrentRemove (tor, deleteFlag, NULL);
    }

  tr_free (torrents);
  return NULL;
}

static const char*
torrentReannounce (tr_session               * session,
                   tr_variant               * args_in,
                   tr_variant               * args_out UNUSED,
                   struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];

      if (tr_torrentCanManualUpdate (tor))
        {
          tr_torrentManualUpdate (tor);
          notify (session, TR_RPC_TORRENT_CHANGED, tor);
        }
    }

  tr_free (torrents);
  return NULL;
}

static const char*
torrentVerify (tr_session               * session,
               tr_variant               * args_in,
               tr_variant               * args_out UNUSED,
               struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);
  for (i=0; i<torrentCount; ++i)
    {
      tr_torrent * tor = torrents[i];
      tr_torrentVerify (tor, NULL, NULL);
      notify (session, TR_RPC_TORRENT_CHANGED, tor);
    }

  tr_free (torrents);
  return NULL;
}

/***
****
***/

static void
addFileStats (const tr_torrent * tor, tr_variant * list)
{
  tr_file_index_t i;
  tr_file_index_t n;
  const tr_info * info = tr_torrentInfo (tor);
  tr_file_stat * files = tr_torrentFiles (tor, &n);

  for (i=0; i<info->fileCount; ++i)
    {
      const tr_file * file = &info->files[i];
      tr_variant * d = tr_variantListAddDict (list, 3);
      tr_variantDictAddInt (d, TR_KEY_bytesCompleted, files[i].bytesCompleted);
      tr_variantDictAddInt (d, TR_KEY_priority, file->priority);
      tr_variantDictAddBool (d, TR_KEY_wanted, !file->dnd);
    }

  tr_torrentFilesFree (files, n);
}

static void
addFiles (const tr_torrent * tor, tr_variant * list)
{
  tr_file_index_t i;
  tr_file_index_t n;
  const tr_info * info = tr_torrentInfo (tor);
  tr_file_stat *  files = tr_torrentFiles (tor, &n);

  for (i=0; i<info->fileCount; ++i)
    {
      const tr_file * file = &info->files[i];
      tr_variant * d = tr_variantListAddDict (list, 3);
      tr_variantDictAddInt (d, TR_KEY_bytesCompleted, files[i].bytesCompleted);
      tr_variantDictAddInt (d, TR_KEY_length, file->length);
      tr_variantDictAddStr (d, TR_KEY_name, file->name);
    }

  tr_torrentFilesFree (files, n);
}

static void
addWebseeds (const tr_info  * info,
             tr_variant     * webseeds)
{
  unsigned int i;

  for (i=0; i< info->webseedCount; ++i)
    tr_variantListAddStr (webseeds, info->webseeds[i]);
}

static void
addTrackers (const tr_info  * info,
             tr_variant     * trackers)
{
  unsigned int i;

  for (i=0; i<info->trackerCount; ++i)
    {
      const tr_tracker_info * t = &info->trackers[i];
      tr_variant * d = tr_variantListAddDict (trackers, 4);
      tr_variantDictAddStr (d, TR_KEY_announce, t->announce);
      tr_variantDictAddInt (d, TR_KEY_id, t->id);
      tr_variantDictAddStr (d, TR_KEY_scrape, t->scrape);
      tr_variantDictAddInt (d, TR_KEY_tier, t->tier);
    }
}

static void
addTrackerStats (const tr_tracker_stat * st, int n, tr_variant * list)
{
  int i;

  for (i=0; i<n; ++i)
    {
      const tr_tracker_stat * s = &st[i];
      tr_variant * d = tr_variantListAddDict (list, 26);
      tr_variantDictAddStr  (d, TR_KEY_announce, s->announce);
      tr_variantDictAddInt  (d, TR_KEY_announceState, s->announceState);
      tr_variantDictAddInt  (d, TR_KEY_downloadCount, s->downloadCount);
      tr_variantDictAddBool (d, TR_KEY_hasAnnounced, s->hasAnnounced);
      tr_variantDictAddBool (d, TR_KEY_hasScraped, s->hasScraped);
      tr_variantDictAddStr  (d, TR_KEY_host, s->host);
      tr_variantDictAddInt  (d, TR_KEY_id, s->id);
      tr_variantDictAddBool (d, TR_KEY_isBackup, s->isBackup);
      tr_variantDictAddInt  (d, TR_KEY_lastAnnouncePeerCount, s->lastAnnouncePeerCount);
      tr_variantDictAddStr  (d, TR_KEY_lastAnnounceResult, s->lastAnnounceResult);
      tr_variantDictAddInt  (d, TR_KEY_lastAnnounceStartTime, s->lastAnnounceStartTime);
      tr_variantDictAddBool (d, TR_KEY_lastAnnounceSucceeded, s->lastAnnounceSucceeded);
      tr_variantDictAddInt  (d, TR_KEY_lastAnnounceTime, s->lastAnnounceTime);
      tr_variantDictAddBool (d, TR_KEY_lastAnnounceTimedOut, s->lastAnnounceTimedOut);
      tr_variantDictAddStr  (d, TR_KEY_lastScrapeResult, s->lastScrapeResult);
      tr_variantDictAddInt  (d, TR_KEY_lastScrapeStartTime, s->lastScrapeStartTime);
      tr_variantDictAddBool (d, TR_KEY_lastScrapeSucceeded, s->lastScrapeSucceeded);
      tr_variantDictAddInt  (d, TR_KEY_lastScrapeTime, s->lastScrapeTime);
      tr_variantDictAddInt  (d, TR_KEY_lastScrapeTimedOut, s->lastScrapeTimedOut);
      tr_variantDictAddInt  (d, TR_KEY_leecherCount, s->leecherCount);
      tr_variantDictAddInt  (d, TR_KEY_nextAnnounceTime, s->nextAnnounceTime);
      tr_variantDictAddInt  (d, TR_KEY_nextScrapeTime, s->nextScrapeTime);
      tr_variantDictAddStr  (d, TR_KEY_scrape, s->scrape);
      tr_variantDictAddInt  (d, TR_KEY_scrapeState, s->scrapeState);
      tr_variantDictAddInt  (d, TR_KEY_seederCount, s->seederCount);
      tr_variantDictAddInt  (d, TR_KEY_tier, s->tier);
    }
}

static void
addPeers (tr_torrent * tor, tr_variant * list)
{
  int i;
  int peerCount;
  tr_peer_stat * peers = tr_torrentPeers (tor, &peerCount);

  tr_variantInitList (list, peerCount);

  for (i=0; i<peerCount; ++i)
    {
      tr_variant * d = tr_variantListAddDict (list, 16);
      const tr_peer_stat * peer = peers + i;
      tr_variantDictAddStr  (d, TR_KEY_address, peer->addr);
      tr_variantDictAddStr  (d, TR_KEY_clientName, peer->client);
      tr_variantDictAddBool (d, TR_KEY_clientIsChoked, peer->clientIsChoked);
      tr_variantDictAddBool (d, TR_KEY_clientIsInterested, peer->clientIsInterested);
      tr_variantDictAddStr  (d, TR_KEY_flagStr, peer->flagStr);
      tr_variantDictAddBool (d, TR_KEY_isDownloadingFrom, peer->isDownloadingFrom);
      tr_variantDictAddBool (d, TR_KEY_isEncrypted, peer->isEncrypted);
      tr_variantDictAddBool (d, TR_KEY_isIncoming, peer->isIncoming);
      tr_variantDictAddBool (d, TR_KEY_isUploadingTo, peer->isUploadingTo);
      tr_variantDictAddBool (d, TR_KEY_isUTP, peer->isUTP);
      tr_variantDictAddBool (d, TR_KEY_peerIsChoked, peer->peerIsChoked);
      tr_variantDictAddBool (d, TR_KEY_peerIsInterested, peer->peerIsInterested);
      tr_variantDictAddInt  (d, TR_KEY_port, peer->port);
      tr_variantDictAddReal (d, TR_KEY_progress, peer->progress);
      tr_variantDictAddInt  (d, TR_KEY_rateToClient, toSpeedBytes (peer->rateToClient_KBps));
      tr_variantDictAddInt  (d, TR_KEY_rateToPeer, toSpeedBytes (peer->rateToPeer_KBps));
    }

  tr_torrentPeersFree (peers, peerCount);
}

static void
addField (tr_torrent       * const tor,
          const tr_info    * const inf,
          const tr_stat    * const st,
          tr_variant       * const d,
          const tr_quark           key)
{
  char * str;

  switch (key)
    {
      case TR_KEY_activityDate:
        tr_variantDictAddInt (d, key, st->activityDate);
        break;

      case TR_KEY_addedDate:
        tr_variantDictAddInt (d, key, st->addedDate);
        break;

      case TR_KEY_bandwidthPriority:
        tr_variantDictAddInt (d, key, tr_torrentGetPriority (tor));
        break;

      case TR_KEY_comment:
        tr_variantDictAddStr (d, key, inf->comment ? inf->comment : "");
        break;

      case TR_KEY_corruptEver:
        tr_variantDictAddInt (d, key, st->corruptEver);
        break;

      case TR_KEY_creator:
        tr_variantDictAddStr (d, key, inf->creator ? inf->creator : "");
        break;

      case TR_KEY_dateCreated:
        tr_variantDictAddInt (d, key, inf->dateCreated);
        break;

      case TR_KEY_desiredAvailable:
        tr_variantDictAddInt (d, key, st->desiredAvailable);
        break;

      case TR_KEY_doneDate:
        tr_variantDictAddInt (d, key, st->doneDate);
        break;

      case TR_KEY_downloadDir:
        tr_variantDictAddStr (d, key, tr_torrentGetDownloadDir (tor));
        break;

      case TR_KEY_downloadedEver:
        tr_variantDictAddInt (d, key, st->downloadedEver);
        break;

      case TR_KEY_downloadLimit:
        tr_variantDictAddInt (d, key, tr_torrentGetSpeedLimit_KBps (tor, TR_DOWN));
        break;

      case TR_KEY_downloadLimited:
        tr_variantDictAddBool (d, key, tr_torrentUsesSpeedLimit (tor, TR_DOWN));
        break;

      case TR_KEY_error:
        tr_variantDictAddInt (d, key, st->error);
        break;

      case TR_KEY_errorString:
        tr_variantDictAddStr (d, key, st->errorString);
        break;

      case TR_KEY_eta:
        tr_variantDictAddInt (d, key, st->eta);
        break;

      case TR_KEY_files:
        addFiles (tor, tr_variantDictAddList (d, key, inf->fileCount));
        break;

      case TR_KEY_fileStats:
        addFileStats (tor, tr_variantDictAddList (d, key, inf->fileCount));
        break;

      case TR_KEY_hashString:
        tr_variantDictAddStr (d, key, tor->info.hashString);
        break;

      case TR_KEY_haveUnchecked:
        tr_variantDictAddInt (d, key, st->haveUnchecked);
        break;

      case TR_KEY_haveValid:
        tr_variantDictAddInt (d, key, st->haveValid);
        break;

      case TR_KEY_honorsSessionLimits:
        tr_variantDictAddBool (d, key, tr_torrentUsesSessionLimits (tor));
        break;

      case TR_KEY_id:
        tr_variantDictAddInt (d, key, st->id);
        break;

      case TR_KEY_isFinished:
        tr_variantDictAddBool (d, key, st->finished);
        break;

      case TR_KEY_isPrivate:
        tr_variantDictAddBool (d, key, tr_torrentIsPrivate (tor));
        break;

      case TR_KEY_isStalled:
        tr_variantDictAddBool (d, key, st->isStalled);
        break;

      case TR_KEY_leftUntilDone:
        tr_variantDictAddInt (d, key, st->leftUntilDone);
        break;

      case TR_KEY_manualAnnounceTime:
        tr_variantDictAddInt (d, key, st->manualAnnounceTime);
        break;

      case TR_KEY_maxConnectedPeers:
        tr_variantDictAddInt (d, key,  tr_torrentGetPeerLimit (tor));
        break;

      case TR_KEY_magnetLink:
        str = tr_torrentGetMagnetLink (tor);
        tr_variantDictAddStr (d, key, str);
        tr_free (str);
        break;

      case TR_KEY_metadataPercentComplete:
        tr_variantDictAddReal (d, key, st->metadataPercentComplete);
        break;

      case TR_KEY_name:
        tr_variantDictAddStr (d, key, tr_torrentName (tor));
        break;

      case TR_KEY_percentDone:
        tr_variantDictAddReal (d, key, st->percentDone);
        break;

      case TR_KEY_peer_limit:
        tr_variantDictAddInt (d, key, tr_torrentGetPeerLimit (tor));
        break;

      case TR_KEY_peers:
        addPeers (tor, tr_variantDictAdd (d, key));
        break;

      case TR_KEY_peersConnected:
        tr_variantDictAddInt (d, key, st->peersConnected);
        break;

      case TR_KEY_peersFrom:
        {
          tr_variant * tmp = tr_variantDictAddDict (d, key, 7);
          const int * f = st->peersFrom;
          tr_variantDictAddInt (tmp, TR_KEY_fromCache,    f[TR_PEER_FROM_RESUME]);
          tr_variantDictAddInt (tmp, TR_KEY_fromDht,      f[TR_PEER_FROM_DHT]);
          tr_variantDictAddInt (tmp, TR_KEY_fromIncoming, f[TR_PEER_FROM_INCOMING]);
          tr_variantDictAddInt (tmp, TR_KEY_fromLpd,      f[TR_PEER_FROM_LPD]);
          tr_variantDictAddInt (tmp, TR_KEY_fromLtep,     f[TR_PEER_FROM_LTEP]);
          tr_variantDictAddInt (tmp, TR_KEY_fromPex,      f[TR_PEER_FROM_PEX]);
          tr_variantDictAddInt (tmp, TR_KEY_fromTracker,  f[TR_PEER_FROM_TRACKER]);
          break;
        }

      case TR_KEY_peersGettingFromUs:
        tr_variantDictAddInt (d, key, st->peersGettingFromUs);
        break;

      case TR_KEY_peersSendingToUs:
        tr_variantDictAddInt (d, key, st->peersSendingToUs);
        break;

      case TR_KEY_pieces:
        if (tr_torrentHasMetadata (tor))
          {
            size_t byte_count = 0;
            void * bytes = tr_torrentCreatePieceBitfield (tor, &byte_count);
            char * str = tr_base64_encode (bytes, byte_count, NULL);
            tr_variantDictAddStr (d, key, str!=NULL ? str : "");
            tr_free (str);
            tr_free (bytes);
          }
        else
          {
            tr_variantDictAddStr (d, key, "");
          }
        break;

      case TR_KEY_pieceCount:
        tr_variantDictAddInt (d, key, inf->pieceCount);
        break;

      case TR_KEY_pieceSize:
        tr_variantDictAddInt (d, key, inf->pieceSize);
        break;

      case TR_KEY_priorities:
        {
          tr_file_index_t i;
          tr_variant * p = tr_variantDictAddList (d, key, inf->fileCount);
          for (i=0; i<inf->fileCount; ++i)
            tr_variantListAddInt (p, inf->files[i].priority);
          break;
        }

      case TR_KEY_queuePosition:
        tr_variantDictAddInt (d, key, st->queuePosition);
        break;

      case TR_KEY_etaIdle:
        tr_variantDictAddInt (d, key, st->etaIdle);
        break;

      case TR_KEY_rateDownload:
        tr_variantDictAddInt (d, key, toSpeedBytes (st->pieceDownloadSpeed_KBps));
        break;

      case TR_KEY_rateUpload:
        tr_variantDictAddInt (d, key, toSpeedBytes (st->pieceUploadSpeed_KBps));
        break;

      case TR_KEY_recheckProgress:
        tr_variantDictAddReal (d, key, st->recheckProgress);
        break;

      case TR_KEY_seedIdleLimit:
        tr_variantDictAddInt (d, key, tr_torrentGetIdleLimit (tor));
        break;

      case TR_KEY_seedIdleMode:
        tr_variantDictAddInt (d, key, tr_torrentGetIdleMode (tor));
        break;

      case TR_KEY_seedRatioLimit:
        tr_variantDictAddReal (d, key, tr_torrentGetRatioLimit (tor));
        break;

      case TR_KEY_seedRatioMode:
        tr_variantDictAddInt (d, key, tr_torrentGetRatioMode (tor));
        break;

      case TR_KEY_sizeWhenDone:
        tr_variantDictAddInt (d, key, st->sizeWhenDone);
        break;

      case TR_KEY_startDate:
        tr_variantDictAddInt (d, key, st->startDate);
        break;

      case TR_KEY_status:
        tr_variantDictAddInt (d, key, st->activity);
        break;

      case TR_KEY_secondsDownloading:
        tr_variantDictAddInt (d, key, st->secondsDownloading);
        break;

      case TR_KEY_secondsSeeding:
        tr_variantDictAddInt (d, key, st->secondsSeeding);
        break;

      case TR_KEY_trackers:
        addTrackers (inf, tr_variantDictAddList (d, key, inf->trackerCount));
        break;

      case TR_KEY_trackerStats:
        {
          int n;
          tr_tracker_stat * s = tr_torrentTrackers (tor, &n);
          addTrackerStats (s, n, tr_variantDictAddList (d, key, n));
          tr_torrentTrackersFree (s, n);
          break;
        }

      case TR_KEY_torrentFile:
        tr_variantDictAddStr (d, key, inf->torrent);
        break;

      case TR_KEY_totalSize:
        tr_variantDictAddInt (d, key, inf->totalSize);
        break;

      case TR_KEY_uploadedEver:
        tr_variantDictAddInt (d, key, st->uploadedEver);
        break;

      case TR_KEY_uploadLimit:
        tr_variantDictAddInt (d, key, tr_torrentGetSpeedLimit_KBps (tor, TR_UP));
        break;

      case TR_KEY_uploadLimited:
        tr_variantDictAddBool (d, key, tr_torrentUsesSpeedLimit (tor, TR_UP));
        break;

      case TR_KEY_uploadRatio:
        tr_variantDictAddReal (d, key, st->ratio);
        break;

      case TR_KEY_wanted:
        {
          tr_file_index_t i;
          tr_variant * w = tr_variantDictAddList (d, key, inf->fileCount);
          for (i=0; i<inf->fileCount; ++i)
            tr_variantListAddInt (w, inf->files[i].dnd ? 0 : 1);
          break;
        }

      case TR_KEY_webseeds:
        addWebseeds (inf, tr_variantDictAddList (d, key, inf->webseedCount));
        break;

      case TR_KEY_webseedsSendingToUs:
        tr_variantDictAddInt (d, key, st->webseedsSendingToUs);
        break;

      default:
        break;
    }
}

static void
addInfo (tr_torrent * tor, tr_variant * d, tr_variant * fields)
{
  const int n = tr_variantListSize (fields);

  tr_variantInitDict (d, n);

  if (n > 0)
    {
      int i;
      const tr_info * const inf = tr_torrentInfo (tor);
      const tr_stat * const st = tr_torrentStat ((tr_torrent*)tor);

      for (i=0; i<n; ++i)
        {
          size_t len;
          const char * str;
          if (tr_variantGetStr (tr_variantListChild (fields, i), &str, &len))
            addField (tor, inf, st, d, tr_quark_new (str, len));
        }
    }
}

static const char*
torrentGet (tr_session               * session,
            tr_variant               * args_in,
            tr_variant               * args_out,
            struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents = getTorrents (session, args_in, &torrentCount);
  tr_variant * list = tr_variantDictAddList (args_out, TR_KEY_torrents, torrentCount);
  tr_variant * fields;
  const char * strVal;
  const char * errmsg = NULL;

  assert (idle_data == NULL);

  if (tr_variantDictFindStr (args_in, TR_KEY_ids, &strVal, NULL) && !strcmp (strVal, "recently-active"))
    {
      int n = 0;
      tr_variant * d;
      const time_t now = tr_time ();
      const int interval = RECENTLY_ACTIVE_SECONDS;
      tr_variant * removed_out = tr_variantDictAddList (args_out, TR_KEY_removed, 0);
      while ((d = tr_variantListChild (&session->removedTorrents, n++)))
        {
          int64_t intVal;
          if (tr_variantDictFindInt (d, TR_KEY_date, &intVal) && (intVal >= now - interval))
            {
              tr_variantDictFindInt (d, TR_KEY_id, &intVal);
              tr_variantListAddInt (removed_out, intVal);
            }
        }
    }

  if (!tr_variantDictFindList (args_in, TR_KEY_fields, &fields))
    errmsg = "no fields specified";
  else for (i=0; i<torrentCount; ++i)
    addInfo (torrents[i], tr_variantListAdd (list), fields);

  tr_free (torrents);
  return errmsg;
}

/***
****
***/

static const char*
setFilePriorities (tr_torrent * tor,
                   int          priority,
                   tr_variant * list)
{
  int i;
  int64_t tmp;
  int fileCount = 0;
  const int n = tr_variantListSize (list);
  const char * errmsg = NULL;
  tr_file_index_t * files = tr_new0 (tr_file_index_t, tor->info.fileCount);

  if (n)
    {
      for (i=0; i<n; ++i)
        {
          if (tr_variantGetInt (tr_variantListChild (list, i), &tmp))
            {
              if (0 <= tmp && tmp < tor->info.fileCount)
                files[fileCount++] = tmp;
              else
                errmsg = "file index out of range";
            }
        }
    }
  else /* if empty set, apply to all */
    {
      tr_file_index_t t;
      for (t=0; t<tor->info.fileCount; ++t)
        files[fileCount++] = t;
    }

  if (fileCount)
    tr_torrentSetFilePriorities (tor, files, fileCount, priority);

  tr_free (files);
  return errmsg;
}

static const char*
setFileDLs (tr_torrent * tor,
            int          do_download,
            tr_variant * list)
{
  int i;
  int64_t tmp;
  int fileCount = 0;
  const int n = tr_variantListSize (list);
  const char * errmsg = NULL;
  tr_file_index_t * files = tr_new0 (tr_file_index_t, tor->info.fileCount);

  if (n) /* if argument list, process them */
    {
      for (i=0; i<n; ++i)
        {
          if (tr_variantGetInt (tr_variantListChild (list, i), &tmp))
            {
              if (0 <= tmp && tmp < tor->info.fileCount)
                files[fileCount++] = tmp;
              else
                errmsg = "file index out of range";
            }
        }
    }
  else /* if empty set, apply to all */
    {
      tr_file_index_t t;

      for (t=0; t<tor->info.fileCount; ++t)
        files[fileCount++] = t;
    }

  if (fileCount)
      tr_torrentSetFileDLs (tor, files, fileCount, do_download);

  tr_free (files);
  return errmsg;
}

static bool
findAnnounceUrl (const tr_tracker_info * t, int n, const char * url, int * pos)
{
  int i;
  bool found = false;

  for (i=0; i<n; ++i)
    {
      if (!strcmp (t[i].announce, url))
        {
          found = true;

          if (pos != NULL)
            *pos = i;

          break;
        }
    }

  return found;
}

static int
copyTrackers (tr_tracker_info * tgt, const tr_tracker_info * src, int n)
{
  int i;
  int maxTier = -1;

  for (i=0; i<n; ++i)
    {
      tgt[i].tier = src[i].tier;
      tgt[i].announce = tr_strdup (src[i].announce);
      maxTier = MAX (maxTier, src[i].tier);
    }

  return maxTier;
}

static void
freeTrackers (tr_tracker_info * trackers, int n)
{
  int i;

  for (i=0; i<n; ++i)
    tr_free (trackers[i].announce);

  tr_free (trackers);
}

static const char*
addTrackerUrls (tr_torrent * tor, tr_variant * urls)
{
  int i;
  int n;
  int tier;
  tr_variant * val;
  tr_tracker_info * trackers;
  bool changed = false;
  const tr_info * inf = tr_torrentInfo (tor);
  const char * errmsg = NULL;

  /* make a working copy of the existing announce list */
  n = inf->trackerCount;
  trackers = tr_new0 (tr_tracker_info, n + tr_variantListSize (urls));
  tier = copyTrackers (trackers, inf->trackers, n);

  /* and add the new ones */
  i = 0;
  while ((val = tr_variantListChild (urls, i++)))
    {
      const char * announce = NULL;

      if ( tr_variantGetStr (val, &announce, NULL)
          && tr_urlIsValidTracker (announce)
          && !findAnnounceUrl (trackers, n, announce, NULL))
        {
          trackers[n].tier = ++tier; /* add a new tier */
          trackers[n].announce = tr_strdup (announce);
          ++n;
          changed = true;
        }
    }

  if (!changed)
    errmsg = "invalid argument";
  else if (!tr_torrentSetAnnounceList (tor, trackers, n))
    errmsg = "error setting announce list";

  freeTrackers (trackers, n);
  return errmsg;
}

static const char*
replaceTrackers (tr_torrent * tor, tr_variant * urls)
{
  int i;
  tr_variant * pair[2];
  tr_tracker_info * trackers;
  bool changed = false;
  const tr_info * inf = tr_torrentInfo (tor);
  const int n = inf->trackerCount;
  const char * errmsg = NULL;

  /* make a working copy of the existing announce list */
  trackers = tr_new0 (tr_tracker_info, n);
  copyTrackers (trackers, inf->trackers, n);

  /* make the substitutions... */
  i = 0;
  while (((pair[0] = tr_variantListChild (urls,i))) &&
         ((pair[1] = tr_variantListChild (urls,i+1))))
    {
      size_t len;
      int64_t pos;
      const char * newval;

      if (tr_variantGetInt (pair[0], &pos)
          && tr_variantGetStr (pair[1], &newval, &len)
          && tr_urlIsValidTracker (newval)
          && pos < n
          && pos >= 0)
        {
          tr_free (trackers[pos].announce);
          trackers[pos].announce = tr_strndup (newval, len);
          changed = true;
        }

      i += 2;
    }

  if (!changed)
    errmsg = "invalid argument";
  else if (!tr_torrentSetAnnounceList (tor, trackers, n))
    errmsg = "error setting announce list";

  freeTrackers (trackers, n);
  return errmsg;
}

static const char*
removeTrackers (tr_torrent * tor, tr_variant * ids)
{
  int i;
  int n;
  int t = 0;
  int dup = -1;
  int * tids;
  tr_variant * val;
  tr_tracker_info * trackers;
  bool changed = false;
  const tr_info * inf = tr_torrentInfo (tor);
  const char * errmsg = NULL;

  /* make a working copy of the existing announce list */
  n = inf->trackerCount;
  tids = tr_new0 (int, n);
  trackers = tr_new0 (tr_tracker_info, n);
  copyTrackers (trackers, inf->trackers, n);

  /* remove the ones specified in the urls list */
  i = 0;
  while ((val = tr_variantListChild (ids, i++)))
    {
      int64_t pos;

      if (tr_variantGetInt (val, &pos) && (0 <= pos) && (pos < n))
        tids[t++] = pos;
    }

  /* sort trackerIds and remove from largest to smallest so there is no need to recacluate array indicies */
  qsort (tids, t, sizeof (int), compareInt);
  while (t--)
    {
      /* check for duplicates */
      if (tids[t] == dup)
        continue;
      tr_removeElementFromArray (trackers, tids[t], sizeof (tr_tracker_info), n--);
      dup = tids[t];
      changed = true;
    }

  if (!changed)
    errmsg = "invalid argument";
  else if (!tr_torrentSetAnnounceList (tor, trackers, n))
    errmsg = "error setting announce list";

  freeTrackers (trackers, n);
  tr_free (tids);
  return errmsg;
}

static const char*
torrentSet (tr_session               * session,
            tr_variant                  * args_in,
            tr_variant                  * args_out UNUSED,
            struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int i;
  int torrentCount;
  tr_torrent ** torrents;
  const char * errmsg = NULL;

  assert (idle_data == NULL);

  torrents = getTorrents (session, args_in, &torrentCount);

  for (i=0; i<torrentCount; ++i)
    {
      int64_t tmp;
      double d;
      tr_variant * files;
      tr_variant * trackers;
      bool boolVal;
      tr_torrent * tor;

      tor = torrents[i];

      if (tr_variantDictFindInt (args_in, TR_KEY_bandwidthPriority, &tmp))
        if (tr_isPriority (tmp))
          tr_torrentSetPriority (tor, tmp);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_files_unwanted, &files))
        errmsg = setFileDLs (tor, false, files);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_files_wanted, &files))
        errmsg = setFileDLs (tor, true, files);

      if (tr_variantDictFindInt (args_in, TR_KEY_peer_limit, &tmp))
        tr_torrentSetPeerLimit (tor, tmp);

      if (!errmsg &&  tr_variantDictFindList (args_in, TR_KEY_priority_high, &files))
        errmsg = setFilePriorities (tor, TR_PRI_HIGH, files);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_priority_low, &files))
        errmsg = setFilePriorities (tor, TR_PRI_LOW, files);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_priority_normal, &files))
        errmsg = setFilePriorities (tor, TR_PRI_NORMAL, files);

      if (tr_variantDictFindInt (args_in, TR_KEY_downloadLimit, &tmp))
        tr_torrentSetSpeedLimit_KBps (tor, TR_DOWN, tmp);

      if (tr_variantDictFindBool (args_in, TR_KEY_downloadLimited, &boolVal))
        tr_torrentUseSpeedLimit (tor, TR_DOWN, boolVal);

      if (tr_variantDictFindBool (args_in, TR_KEY_honorsSessionLimits, &boolVal))
        tr_torrentUseSessionLimits (tor, boolVal);

      if (tr_variantDictFindInt (args_in, TR_KEY_uploadLimit, &tmp))
        tr_torrentSetSpeedLimit_KBps (tor, TR_UP, tmp);

      if (tr_variantDictFindBool (args_in, TR_KEY_uploadLimited, &boolVal))
        tr_torrentUseSpeedLimit (tor, TR_UP, boolVal);

      if (tr_variantDictFindInt (args_in, TR_KEY_seedIdleLimit, &tmp))
        tr_torrentSetIdleLimit (tor, tmp);

      if (tr_variantDictFindInt (args_in, TR_KEY_seedIdleMode, &tmp))
        tr_torrentSetIdleMode (tor, tmp);

      if (tr_variantDictFindReal (args_in, TR_KEY_seedRatioLimit, &d))
        tr_torrentSetRatioLimit (tor, d);

      if (tr_variantDictFindInt (args_in, TR_KEY_seedRatioMode, &tmp))
        tr_torrentSetRatioMode (tor, tmp);

      if (tr_variantDictFindInt (args_in, TR_KEY_queuePosition, &tmp))
        tr_torrentSetQueuePosition (tor, tmp);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_trackerAdd, &trackers))
        errmsg = addTrackerUrls (tor, trackers);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_trackerRemove, &trackers))
        errmsg = removeTrackers (tor, trackers);

      if (!errmsg && tr_variantDictFindList (args_in, TR_KEY_trackerReplace, &trackers))
        errmsg = replaceTrackers (tor, trackers);

      notify (session, TR_RPC_TORRENT_CHANGED, tor);
    }

  tr_free (torrents);
  return errmsg;
}

static const char*
torrentSetLocation (tr_session               * session,
                    tr_variant               * args_in,
                    tr_variant               * args_out UNUSED,
                    struct tr_rpc_idle_data  * idle_data UNUSED)
{
  const char * errmsg = NULL;
  const char * location = NULL;

  assert (idle_data == NULL);

  if (!tr_variantDictFindStr (args_in, TR_KEY_location, &location, NULL))
    {
      errmsg = "no location";
    }
  else
    {
      bool move;
      int i, torrentCount;
      tr_torrent ** torrents = getTorrents (session, args_in, &torrentCount);

      if (!tr_variantDictFindBool (args_in, TR_KEY_move, &move))
        move = false;

      for (i=0; i<torrentCount; ++i)
        {
          tr_torrent * tor = torrents[i];
          tr_torrentSetLocation (tor, location, move, NULL, NULL);
          notify (session, TR_RPC_TORRENT_MOVED, tor);
        }

      tr_free (torrents);
    }

  return errmsg;
}

/***
****
***/

static void
torrentRenamePathDone (tr_torrent  * tor,
                       const char  * oldpath,
                       const char  * newname,
                       int           error,
                       void        * user_data)
{
  const char * result;
  struct tr_rpc_idle_data * data = user_data;

  tr_variantDictAddInt (data->args_out, TR_KEY_id, tr_torrentId(tor));
  tr_variantDictAddStr (data->args_out, TR_KEY_path, oldpath);
  tr_variantDictAddStr (data->args_out, TR_KEY_name, newname);

  if (error == 0)
    result = NULL;
  else
    result = tr_strerror (error);

  tr_idle_function_done (data, result);
}

static const char*
torrentRenamePath (tr_session               * session,
                   tr_variant               * args_in,
                   tr_variant               * args_out UNUSED,
                   struct tr_rpc_idle_data  * idle_data)
{
  int torrentCount;
  tr_torrent ** torrents;
  const char * oldpath = NULL;
  const char * newname = NULL;

  tr_variantDictFindStr (args_in, TR_KEY_path, &oldpath, NULL);
  tr_variantDictFindStr (args_in, TR_KEY_name, &newname, NULL);
  torrents = getTorrents (session, args_in, &torrentCount);

  if (torrentCount == 1)
    tr_torrentRenamePath (torrents[0], oldpath, newname, torrentRenamePathDone, idle_data);
  else
    tr_idle_function_done (idle_data, "torrent-rename-path requires 1 torrent");

  /* cleanup */
  tr_free (torrents);
  return NULL; /* ignored */
}

/***
****
***/

static void
portTested (tr_session       * session UNUSED,
            bool               did_connect UNUSED,
            bool               did_timeout UNUSED,
            long               response_code,
            const void       * response,
            size_t             response_byte_count,
            void             * user_data)
{
  char result[1024];
  struct tr_rpc_idle_data * data = user_data;

  if (response_code != 200)
    {
      tr_snprintf (result, sizeof (result), "portTested: http error %ld: %s",
                   response_code, tr_webGetResponseStr (response_code));
    }
  else /* success */
    {
      const bool isOpen = response_byte_count && * (char*)response == '1';
      tr_variantDictAddBool (data->args_out, TR_KEY_port_is_open, isOpen);
      tr_snprintf (result, sizeof (result), "success");
    }

    tr_idle_function_done (data, result);
}

static const char*
portTest (tr_session               * session,
          tr_variant               * args_in UNUSED,
          tr_variant               * args_out UNUSED,
          struct tr_rpc_idle_data  * idle_data)
{
  const int port = tr_sessionGetPeerPort (session);
  char * url = tr_strdup_printf ("http://portcheck.transmissionbt.com/%d", port);
  tr_webRun (session, url, portTested, idle_data);
  tr_free (url);
  return NULL;
}

/***
****
***/

static void
gotNewBlocklist (tr_session       * session,
                 bool               did_connect UNUSED,
                 bool               did_timeout UNUSED,
                 long               response_code,
                 const void       * response,
                 size_t             response_byte_count,
                 void             * user_data)
{
  char result[1024];
  struct tr_rpc_idle_data * data = user_data;

  *result = '\0';

  if (response_code != 200)
    {
      tr_snprintf (result, sizeof (result), "gotNewBlocklist: http error %ld: %s",
                   response_code, tr_webGetResponseStr (response_code));
    }
  else /* successfully fetched the blocklist... */
    {
      tr_sys_file_t fd;
      int err;
      char * filename;
      z_stream stream;
      const char * configDir = tr_sessionGetConfigDir (session);
      const size_t buflen = 1024 * 128; /* 128 KiB buffer */
      uint8_t * buf = tr_valloc (buflen);
      tr_error * error = NULL;

      /* this is an odd Magic Number required by zlib to enable gz support.
         See zlib's inflateInit2 () documentation for a full description */
      const int windowBits = 15 + 32;

      stream.zalloc = (alloc_func) Z_NULL;
      stream.zfree = (free_func) Z_NULL;
      stream.opaque = (voidpf) Z_NULL;
      stream.next_in = (void*) response;
      stream.avail_in = response_byte_count;
      inflateInit2 (&stream, windowBits);

      filename = tr_buildPath (configDir, "blocklist.tmp.XXXXXX", NULL);
      fd = tr_sys_file_open_temp (filename, &error);
      if (fd == TR_BAD_SYS_FILE)
        {
          tr_snprintf (result, sizeof (result), _("Couldn't save file \"%1$s\": %2$s"), filename, error->message);
          tr_error_clear (&error);
        }

      for (;;)
        {
          stream.next_out = (void*) buf;
          stream.avail_out = buflen;
          err = inflate (&stream, Z_NO_FLUSH);

          if (stream.avail_out < buflen)
            {
              if (!tr_sys_file_write (fd, buf, buflen - stream.avail_out, NULL, &error))
                {
                  tr_snprintf (result, sizeof (result), _("Couldn't save file \"%1$s\": %2$s"), filename, error->message);
                  tr_error_clear (&error);
                  break;
                }
            }

          if (err != Z_OK)
            {
              if ((err != Z_STREAM_END) && (err != Z_DATA_ERROR))
                tr_snprintf (result, sizeof (result), _("Error uncompressing blocklist: %s (%d)"), zError (err), err);
              break;
            }
        }

      inflateEnd (&stream);

      if (err == Z_DATA_ERROR) /* couldn't inflate it... it's probably already uncompressed */
        if (!tr_sys_file_write (fd, response, response_byte_count, NULL, &error))
          {
            tr_snprintf (result, sizeof (result), _("Couldn't save file \"%1$s\": %2$s"), filename, error->message);
            tr_error_clear (&error);
          }

      tr_sys_file_close (fd, NULL);

      if (*result)
        {
          tr_logAddError ("%s", result);
        }
      else
        {
          /* feed it to the session and give the client a response */
          const int rule_count = tr_blocklistSetContent (session, filename);
          tr_variantDictAddInt (data->args_out, TR_KEY_blocklist_size, rule_count);
          tr_snprintf (result, sizeof (result), "success");
        }

      tr_sys_path_remove (filename, NULL);
      tr_free (filename);
      tr_free (buf);
    }

  tr_idle_function_done (data, result);
}

static const char*
blocklistUpdate (tr_session               * session,
                 tr_variant               * args_in UNUSED,
                 tr_variant               * args_out UNUSED,
                 struct tr_rpc_idle_data  * idle_data)
{
  tr_webRun (session, session->blocklist_url, gotNewBlocklist, idle_data);
  return NULL;
}

/***
****
***/

static void
addTorrentImpl (struct tr_rpc_idle_data * data, tr_ctor * ctor)
{
  int err;
  int duplicate_id;
  const char * result;
  tr_torrent * tor;
  tr_quark key;

  err = 0;
  duplicate_id = 0;
  tor = tr_torrentNew (ctor, &err, &duplicate_id);
  tr_ctorFree (ctor);

  if (!err)
    {
      key = TR_KEY_torrent_added;
      result = NULL;
    }
  else if (err == TR_PARSE_DUPLICATE)
    {
      tor = tr_torrentFindFromId (data->session, duplicate_id);
      key = TR_KEY_torrent_duplicate;
      result = "duplicate torrent";
    }
  else /* err == TR_PARSE_ERR */
    {
      key = 0;
      result = "invalid or corrupt torrent file";
    }

  if (tor && key)
    {
      tr_variant fields;
      tr_variantInitList (&fields, 3);
      tr_variantListAddStr (&fields, "id");
      tr_variantListAddStr (&fields, "name");
      tr_variantListAddStr (&fields, "hashString");
      addInfo (tor, tr_variantDictAdd (data->args_out, key), &fields);
      if (result == NULL)
        notify (data->session, TR_RPC_TORRENT_ADDED, tor);
      tr_variantFree (&fields);
      result = NULL;
    }

  tr_idle_function_done (data, result);
}


struct add_torrent_idle_data
{
  struct tr_rpc_idle_data * data;
  tr_ctor * ctor;
};

static void
gotMetadataFromURL (tr_session       * session UNUSED,
                    bool               did_connect UNUSED,
                    bool               did_timeout UNUSED,
                    long               response_code,
                    const void       * response,
                    size_t             response_byte_count,
                    void             * user_data)
{
  struct add_torrent_idle_data * data = user_data;

  dbgmsg ("torrentAdd: HTTP response code was %ld (%s); response length was %"TR_PRIuSIZE" bytes",
          response_code, tr_webGetResponseStr (response_code), response_byte_count);

  if (response_code==200 || response_code==221) /* http or ftp success.. */
    {
      tr_ctorSetMetainfo (data->ctor, response, response_byte_count);
      addTorrentImpl (data->data, data->ctor);
    }
  else
    {
      char result[1024];
      tr_snprintf (result, sizeof (result), "gotMetadataFromURL: http error %ld: %s",
                   response_code, tr_webGetResponseStr (response_code));
      tr_idle_function_done (data->data, result);
    }

  tr_free (data);
}

static bool
isCurlURL (const char * filename)
{
  if (filename == NULL)
    return false;

  return !strncmp (filename, "ftp://", 6) ||
         !strncmp (filename, "http://", 7) ||
         !strncmp (filename, "https://", 8);
}

static tr_file_index_t*
fileListFromList (tr_variant * list, tr_file_index_t * setmeCount)
{
  size_t i;
  const size_t childCount = tr_variantListSize (list);
  tr_file_index_t n = 0;
  tr_file_index_t * files = tr_new0 (tr_file_index_t, childCount);

  for (i=0; i<childCount; ++i)
    {
      int64_t intVal;
      if (tr_variantGetInt (tr_variantListChild (list, i), &intVal))
        files[n++] = (tr_file_index_t)intVal;
    }

  *setmeCount = n;
  return files;
}

static const char*
torrentAdd (tr_session               * session,
            tr_variant               * args_in,
            tr_variant               * args_out UNUSED,
            struct tr_rpc_idle_data  * idle_data)
{
  const char * filename = NULL;
  const char * metainfo_base64 = NULL;

  assert (idle_data != NULL);

  tr_variantDictFindStr (args_in, TR_KEY_filename, &filename, NULL);
  tr_variantDictFindStr (args_in, TR_KEY_metainfo, &metainfo_base64, NULL);
  if (!filename && !metainfo_base64)
    {
      return "no filename or metainfo specified";
    }
  else
    {
      int64_t i;
      bool boolVal;
      tr_variant * l;
      const char * str;
      const char * cookies = NULL;
      tr_ctor * ctor = tr_ctorNew (session);

      /* set the optional arguments */

      tr_variantDictFindStr (args_in, TR_KEY_cookies, &cookies, NULL);

      if (tr_variantDictFindStr (args_in, TR_KEY_download_dir, &str, NULL))
        tr_ctorSetDownloadDir (ctor, TR_FORCE, str);

      if (tr_variantDictFindBool (args_in, TR_KEY_paused, &boolVal))
        tr_ctorSetPaused (ctor, TR_FORCE, boolVal);

      if (tr_variantDictFindInt (args_in, TR_KEY_peer_limit, &i))
        tr_ctorSetPeerLimit (ctor, TR_FORCE, i);

      if (tr_variantDictFindInt (args_in, TR_KEY_bandwidthPriority, &i))
        tr_ctorSetBandwidthPriority (ctor, i);

      if (tr_variantDictFindList (args_in, TR_KEY_files_unwanted, &l))
        {
          tr_file_index_t fileCount;
          tr_file_index_t * files = fileListFromList (l, &fileCount);
          tr_ctorSetFilesWanted (ctor, files, fileCount, false);
          tr_free (files);
        }

      if (tr_variantDictFindList (args_in, TR_KEY_files_wanted, &l))
        {
          tr_file_index_t fileCount;
          tr_file_index_t * files = fileListFromList (l, &fileCount);
          tr_ctorSetFilesWanted (ctor, files, fileCount, true);
          tr_free (files);
        }

      if (tr_variantDictFindList (args_in, TR_KEY_priority_low, &l))
        {
          tr_file_index_t fileCount;
          tr_file_index_t * files = fileListFromList (l, &fileCount);
          tr_ctorSetFilePriorities (ctor, files, fileCount, TR_PRI_LOW);
          tr_free (files);
        }

      if (tr_variantDictFindList (args_in, TR_KEY_priority_normal, &l))
        {
          tr_file_index_t fileCount;
          tr_file_index_t * files = fileListFromList (l, &fileCount);
          tr_ctorSetFilePriorities (ctor, files, fileCount, TR_PRI_NORMAL);
          tr_free (files);
        }

      if (tr_variantDictFindList (args_in, TR_KEY_priority_high, &l))
        {
          tr_file_index_t fileCount;
          tr_file_index_t * files = fileListFromList (l, &fileCount);
          tr_ctorSetFilePriorities (ctor, files, fileCount, TR_PRI_HIGH);
          tr_free (files);
        }

      dbgmsg ("torrentAdd: filename is \"%s\"", filename ? filename : " (null)");

      if (isCurlURL (filename))
        {
          struct add_torrent_idle_data * d = tr_new0 (struct add_torrent_idle_data, 1);
          d->data = idle_data;
          d->ctor = ctor;
          tr_webRunWithCookies (session, filename, cookies, gotMetadataFromURL, d);
        }
      else
        {
          char * fname = tr_strstrip (tr_strdup (filename));

          if (fname == NULL)
            {
              size_t len;
              char * metainfo = tr_base64_decode_str (metainfo_base64, &len);
              tr_ctorSetMetainfo (ctor, (uint8_t*)metainfo, len);
              tr_free (metainfo);
            }
          else if (!strncmp (fname, "magnet:?", 8))
            {
              tr_ctorSetMetainfoFromMagnetLink (ctor, fname);
            }
          else
            {
              tr_ctorSetMetainfoFromFile (ctor, fname);
            }

          addTorrentImpl (idle_data, ctor);

          tr_free (fname);
        }

    }

  return NULL;
}

/***
****
***/

static const char*
sessionSet (tr_session               * session,
            tr_variant               * args_in,
            tr_variant               * args_out UNUSED,
            struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int64_t i;
  double d;
  bool boolVal;
  const char * str;

  assert (idle_data == NULL);

  if (tr_variantDictFindInt (args_in, TR_KEY_cache_size_mb, &i))
    tr_sessionSetCacheLimit_MB (session, i);

  if (tr_variantDictFindInt (args_in, TR_KEY_alt_speed_up, &i))
    tr_sessionSetAltSpeed_KBps (session, TR_UP, i);

  if (tr_variantDictFindInt (args_in, TR_KEY_alt_speed_down, &i))
    tr_sessionSetAltSpeed_KBps (session, TR_DOWN, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_alt_speed_enabled, &boolVal))
    tr_sessionUseAltSpeed (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_alt_speed_time_begin, &i))
    tr_sessionSetAltSpeedBegin (session, i);

  if (tr_variantDictFindInt (args_in, TR_KEY_alt_speed_time_end, &i))
    tr_sessionSetAltSpeedEnd (session, i);

  if (tr_variantDictFindInt (args_in, TR_KEY_alt_speed_time_day, &i))
    tr_sessionSetAltSpeedDay (session, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_alt_speed_time_enabled, &boolVal))
    tr_sessionUseAltSpeedTime (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_blocklist_enabled, &boolVal))
    tr_blocklistSetEnabled (session, boolVal);

  if (tr_variantDictFindStr (args_in, TR_KEY_blocklist_url, &str, NULL))
    tr_blocklistSetURL (session, str);

  if (tr_variantDictFindStr (args_in, TR_KEY_download_dir, &str, NULL))
    tr_sessionSetDownloadDir (session, str);

  if (tr_variantDictFindInt (args_in, TR_KEY_queue_stalled_minutes, &i))
    tr_sessionSetQueueStalledMinutes (session, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_queue_stalled_enabled, &boolVal))
    tr_sessionSetQueueStalledEnabled (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_download_queue_size, &i))
    tr_sessionSetQueueSize (session, TR_DOWN, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_download_queue_enabled, &boolVal))
    tr_sessionSetQueueEnabled (session, TR_DOWN, boolVal);

  if (tr_variantDictFindStr (args_in, TR_KEY_incomplete_dir, &str, NULL))
    tr_sessionSetIncompleteDir (session, str);

  if (tr_variantDictFindBool (args_in, TR_KEY_incomplete_dir_enabled, &boolVal))
    tr_sessionSetIncompleteDirEnabled (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_peer_limit_global, &i))
    tr_sessionSetPeerLimit (session, i);

  if (tr_variantDictFindInt (args_in, TR_KEY_peer_limit_per_torrent, &i))
    tr_sessionSetPeerLimitPerTorrent (session, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_pex_enabled, &boolVal))
    tr_sessionSetPexEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_dht_enabled, &boolVal))
    tr_sessionSetDHTEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_utp_enabled, &boolVal))
    tr_sessionSetUTPEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_lpd_enabled, &boolVal))
    tr_sessionSetLPDEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_peer_port_random_on_start, &boolVal))
    tr_sessionSetPeerPortRandomOnStart (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_peer_port, &i))
    tr_sessionSetPeerPort (session, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_port_forwarding_enabled, &boolVal))
    tr_sessionSetPortForwardingEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_rename_partial_files, &boolVal))
    tr_sessionSetIncompleteFileNamingEnabled (session, boolVal);

  if (tr_variantDictFindReal (args_in, TR_KEY_seedRatioLimit, &d))
    tr_sessionSetRatioLimit (session, d);

  if (tr_variantDictFindBool (args_in, TR_KEY_seedRatioLimited, &boolVal))
    tr_sessionSetRatioLimited (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_idle_seeding_limit, &i))
    tr_sessionSetIdleLimit (session, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_idle_seeding_limit_enabled, &boolVal))
    tr_sessionSetIdleLimited (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_start_added_torrents, &boolVal))
    tr_sessionSetPaused (session, !boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_seed_queue_enabled, &boolVal))
    tr_sessionSetQueueEnabled (session, TR_UP, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_seed_queue_size, &i))
    tr_sessionSetQueueSize (session, TR_UP, i);

  if (tr_variantDictFindStr (args_in, TR_KEY_script_torrent_done_filename, &str, NULL))
    tr_sessionSetTorrentDoneScript (session, str);

  if (tr_variantDictFindBool (args_in, TR_KEY_script_torrent_done_enabled, &boolVal))
    tr_sessionSetTorrentDoneScriptEnabled (session, boolVal);

  if (tr_variantDictFindBool (args_in, TR_KEY_trash_original_torrent_files, &boolVal))
    tr_sessionSetDeleteSource (session, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_speed_limit_down, &i))
    tr_sessionSetSpeedLimit_KBps (session, TR_DOWN, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_speed_limit_down_enabled, &boolVal))
    tr_sessionLimitSpeed (session, TR_DOWN, boolVal);

  if (tr_variantDictFindInt (args_in, TR_KEY_speed_limit_up, &i))
    tr_sessionSetSpeedLimit_KBps (session, TR_UP, i);

  if (tr_variantDictFindBool (args_in, TR_KEY_speed_limit_up_enabled, &boolVal))
    tr_sessionLimitSpeed (session, TR_UP, boolVal);

  if (tr_variantDictFindStr (args_in, TR_KEY_encryption, &str, NULL))
    {
      if (!tr_strcmp0 (str, "required"))
        tr_sessionSetEncryption (session, TR_ENCRYPTION_REQUIRED);
      else if (!tr_strcmp0 (str, "tolerated"))
        tr_sessionSetEncryption (session, TR_CLEAR_PREFERRED);
      else
        tr_sessionSetEncryption (session, TR_ENCRYPTION_PREFERRED);
    }

  notify (session, TR_RPC_SESSION_CHANGED, NULL);

  return NULL;
}

static const char*
sessionStats (tr_session               * session,
              tr_variant               * args_in UNUSED,
              tr_variant               * args_out,
              struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int running = 0;
  int total = 0;
  tr_variant * d;
  tr_session_stats currentStats = { 0.0f, 0, 0, 0, 0, 0 };
  tr_session_stats cumulativeStats = { 0.0f, 0, 0, 0, 0, 0 };
  tr_torrent * tor = NULL;

  assert (idle_data == NULL);

  while ((tor = tr_torrentNext (session, tor)))
    {
      ++total;

      if (tor->isRunning)
        ++running;
    }

  tr_sessionGetStats (session, &currentStats);
  tr_sessionGetCumulativeStats (session, &cumulativeStats);

  tr_variantDictAddInt  (args_out, TR_KEY_activeTorrentCount, running);
  tr_variantDictAddReal (args_out, TR_KEY_downloadSpeed, tr_sessionGetPieceSpeed_Bps (session, TR_DOWN));
  tr_variantDictAddInt  (args_out, TR_KEY_pausedTorrentCount, total - running);
  tr_variantDictAddInt  (args_out, TR_KEY_torrentCount, total);
  tr_variantDictAddReal (args_out, TR_KEY_uploadSpeed, tr_sessionGetPieceSpeed_Bps (session, TR_UP));

  d = tr_variantDictAddDict (args_out, TR_KEY_cumulative_stats, 5);
  tr_variantDictAddInt (d, TR_KEY_downloadedBytes, cumulativeStats.downloadedBytes);
  tr_variantDictAddInt (d, TR_KEY_filesAdded, cumulativeStats.filesAdded);
  tr_variantDictAddInt (d, TR_KEY_secondsActive, cumulativeStats.secondsActive);
  tr_variantDictAddInt (d, TR_KEY_sessionCount, cumulativeStats.sessionCount);
  tr_variantDictAddInt (d, TR_KEY_uploadedBytes, cumulativeStats.uploadedBytes);

  d = tr_variantDictAddDict (args_out, TR_KEY_current_stats, 5);
  tr_variantDictAddInt (d, TR_KEY_downloadedBytes, currentStats.downloadedBytes);
  tr_variantDictAddInt (d, TR_KEY_filesAdded, currentStats.filesAdded);
  tr_variantDictAddInt (d, TR_KEY_secondsActive, currentStats.secondsActive);
  tr_variantDictAddInt (d, TR_KEY_sessionCount, currentStats.sessionCount);
  tr_variantDictAddInt (d, TR_KEY_uploadedBytes, currentStats.uploadedBytes);

  return NULL;
}

static const char*
sessionGet (tr_session               * s,
            tr_variant               * args_in UNUSED,
            tr_variant               * args_out,
            struct tr_rpc_idle_data  * idle_data UNUSED)
{
  const char * str;
  tr_variant * d = args_out;

  assert (idle_data == NULL);
  tr_variantDictAddInt  (d, TR_KEY_alt_speed_up, tr_sessionGetAltSpeed_KBps (s,TR_UP));
  tr_variantDictAddInt  (d, TR_KEY_alt_speed_down, tr_sessionGetAltSpeed_KBps (s,TR_DOWN));
  tr_variantDictAddBool (d, TR_KEY_alt_speed_enabled, tr_sessionUsesAltSpeed (s));
  tr_variantDictAddInt  (d, TR_KEY_alt_speed_time_begin, tr_sessionGetAltSpeedBegin (s));
  tr_variantDictAddInt  (d, TR_KEY_alt_speed_time_end,tr_sessionGetAltSpeedEnd (s));
  tr_variantDictAddInt  (d, TR_KEY_alt_speed_time_day,tr_sessionGetAltSpeedDay (s));
  tr_variantDictAddBool (d, TR_KEY_alt_speed_time_enabled, tr_sessionUsesAltSpeedTime (s));
  tr_variantDictAddBool (d, TR_KEY_blocklist_enabled, tr_blocklistIsEnabled (s));
  tr_variantDictAddStr  (d, TR_KEY_blocklist_url, tr_blocklistGetURL (s));
  tr_variantDictAddInt  (d, TR_KEY_cache_size_mb, tr_sessionGetCacheLimit_MB (s));
  tr_variantDictAddInt  (d, TR_KEY_blocklist_size, tr_blocklistGetRuleCount (s));
  tr_variantDictAddStr  (d, TR_KEY_config_dir, tr_sessionGetConfigDir (s));
  tr_variantDictAddStr  (d, TR_KEY_download_dir, tr_sessionGetDownloadDir (s));
  tr_variantDictAddInt  (d, TR_KEY_download_dir_free_space, tr_device_info_get_free_space (s->downloadDir));
  tr_variantDictAddBool (d, TR_KEY_download_queue_enabled, tr_sessionGetQueueEnabled (s, TR_DOWN));
  tr_variantDictAddInt  (d, TR_KEY_download_queue_size, tr_sessionGetQueueSize (s, TR_DOWN));
  tr_variantDictAddInt  (d, TR_KEY_peer_limit_global, tr_sessionGetPeerLimit (s));
  tr_variantDictAddInt  (d, TR_KEY_peer_limit_per_torrent, tr_sessionGetPeerLimitPerTorrent (s));
  tr_variantDictAddStr  (d, TR_KEY_incomplete_dir, tr_sessionGetIncompleteDir (s));
  tr_variantDictAddBool (d, TR_KEY_incomplete_dir_enabled, tr_sessionIsIncompleteDirEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_pex_enabled, tr_sessionIsPexEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_utp_enabled, tr_sessionIsUTPEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_dht_enabled, tr_sessionIsDHTEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_lpd_enabled, tr_sessionIsLPDEnabled (s));
  tr_variantDictAddInt  (d, TR_KEY_peer_port, tr_sessionGetPeerPort (s));
  tr_variantDictAddBool (d, TR_KEY_peer_port_random_on_start, tr_sessionGetPeerPortRandomOnStart (s));
  tr_variantDictAddBool (d, TR_KEY_port_forwarding_enabled, tr_sessionIsPortForwardingEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_rename_partial_files, tr_sessionIsIncompleteFileNamingEnabled (s));
  tr_variantDictAddInt  (d, TR_KEY_rpc_version, RPC_VERSION);
  tr_variantDictAddInt  (d, TR_KEY_rpc_version_minimum, RPC_VERSION_MIN);
  tr_variantDictAddReal (d, TR_KEY_seedRatioLimit, tr_sessionGetRatioLimit (s));
  tr_variantDictAddBool (d, TR_KEY_seedRatioLimited, tr_sessionIsRatioLimited (s));
  tr_variantDictAddInt  (d, TR_KEY_idle_seeding_limit, tr_sessionGetIdleLimit (s));
  tr_variantDictAddBool (d, TR_KEY_idle_seeding_limit_enabled, tr_sessionIsIdleLimited (s));
  tr_variantDictAddBool (d, TR_KEY_seed_queue_enabled, tr_sessionGetQueueEnabled (s, TR_UP));
  tr_variantDictAddInt  (d, TR_KEY_seed_queue_size, tr_sessionGetQueueSize (s, TR_UP));
  tr_variantDictAddBool (d, TR_KEY_start_added_torrents, !tr_sessionGetPaused (s));
  tr_variantDictAddBool (d, TR_KEY_trash_original_torrent_files, tr_sessionGetDeleteSource (s));
  tr_variantDictAddInt  (d, TR_KEY_speed_limit_up, tr_sessionGetSpeedLimit_KBps (s, TR_UP));
  tr_variantDictAddBool (d, TR_KEY_speed_limit_up_enabled, tr_sessionIsSpeedLimited (s, TR_UP));
  tr_variantDictAddInt  (d, TR_KEY_speed_limit_down, tr_sessionGetSpeedLimit_KBps (s, TR_DOWN));
  tr_variantDictAddBool (d, TR_KEY_speed_limit_down_enabled, tr_sessionIsSpeedLimited (s, TR_DOWN));
  tr_variantDictAddStr  (d, TR_KEY_script_torrent_done_filename, tr_sessionGetTorrentDoneScript (s));
  tr_variantDictAddBool (d, TR_KEY_script_torrent_done_enabled, tr_sessionIsTorrentDoneScriptEnabled (s));
  tr_variantDictAddBool (d, TR_KEY_queue_stalled_enabled, tr_sessionGetQueueStalledEnabled (s));
  tr_variantDictAddInt  (d, TR_KEY_queue_stalled_minutes, tr_sessionGetQueueStalledMinutes (s));
  tr_formatter_get_units (tr_variantDictAddDict (d, TR_KEY_units, 0));
  tr_variantDictAddStr  (d, TR_KEY_version, LONG_VERSION_STRING);
  switch (tr_sessionGetEncryption (s))
    {
      case TR_CLEAR_PREFERRED: str = "tolerated"; break;
      case TR_ENCRYPTION_REQUIRED: str = "required"; break;
      default: str = "preferred"; break;
    }
  tr_variantDictAddStr (d, TR_KEY_encryption, str);

  return NULL;
}

static const char*
freeSpace (tr_session               * session,
           tr_variant               * args_in,
           tr_variant               * args_out,
           struct tr_rpc_idle_data  * idle_data UNUSED)
{
  int tmperr;
  const char * path = NULL;
  const char * err = NULL;
  int64_t free_space = -1;

  /* get the free space */
  tr_variantDictFindStr (args_in, TR_KEY_path, &path, NULL);
  tmperr = errno;
  errno = 0;
  free_space = tr_sessionGetDirFreeSpace (session, path);
  if (free_space < 0)
    err = tr_strerror (errno);
  errno = tmperr;

  /* response */
  if (path != NULL)
    tr_variantDictAddStr (args_out, TR_KEY_path, path);
  tr_variantDictAddInt (args_out, TR_KEY_size_bytes, free_space);
  return err;
}

/***
****
***/

static const char*
sessionClose (tr_session               * session,
              tr_variant               * args_in UNUSED,
              tr_variant               * args_out UNUSED,
              struct tr_rpc_idle_data  * idle_data UNUSED)
{
  notify (session, TR_RPC_SESSION_CLOSE, NULL);
  return NULL;
}

/***
****
***/

typedef const char* (*handler)(tr_session*, tr_variant*, tr_variant*, struct tr_rpc_idle_data *);

static struct method
{
  const char *  name;
  bool          immediate;
  handler       func;
}
methods[] =
{
  { "port-test",             false, portTest            },
  { "blocklist-update",      false, blocklistUpdate     },
  { "free-space",            true,  freeSpace           },
  { "session-close",         true,  sessionClose        },
  { "session-get",           true,  sessionGet          },
  { "session-set",           true,  sessionSet          },
  { "session-stats",         true,  sessionStats        },
  { "torrent-add",           false, torrentAdd          },
  { "torrent-get",           true,  torrentGet          },
  { "torrent-remove",        true,  torrentRemove       },
  { "torrent-rename-path",   false, torrentRenamePath   },
  { "torrent-set",           true,  torrentSet          },
  { "torrent-set-location",  true,  torrentSetLocation  },
  { "torrent-start",         true,  torrentStart        },
  { "torrent-start-now",     true,  torrentStartNow     },
  { "torrent-stop",          true,  torrentStop         },
  { "torrent-verify",        true,  torrentVerify       },
  { "torrent-reannounce",    true,  torrentReannounce   },
  { "queue-move-top",        true,  queueMoveTop        },
  { "queue-move-up",         true,  queueMoveUp         },
  { "queue-move-down",       true,  queueMoveDown       },
  { "queue-move-bottom",     true,  queueMoveBottom     }
};

static void
noop_response_callback (tr_session       * session UNUSED,
                        struct evbuffer  * response UNUSED,
                        void             * user_data UNUSED)
{
}

static void
request_exec (tr_session             * session,
              tr_variant             * request,
              tr_rpc_response_func     callback,
              void                   * callback_user_data)
{
  int i;
  const char * str;
  tr_variant * args_in = tr_variantDictFind (request, TR_KEY_arguments);
  const char * result = NULL;

  if (callback == NULL)
    callback = noop_response_callback;

  /* parse the request */
  if (!tr_variantDictFindStr (request, TR_KEY_method, &str, NULL))
    {
      result = "no method name";
    }
  else
    {
      const int n = TR_N_ELEMENTS (methods);

      for (i=0; i<n; ++i)
        if (!strcmp (str, methods[i].name))
          break;

      if (i ==n)
        result = "method name not recognized";
    }

  /* if we couldn't figure out which method to use, return an error */
  if (result != NULL)
    {
      int64_t tag;
      tr_variant response;
      struct evbuffer * buf;

      tr_variantInitDict (&response, 3);
      tr_variantDictAddDict (&response, TR_KEY_arguments, 0);
      tr_variantDictAddStr (&response, TR_KEY_result, result);
      if (tr_variantDictFindInt (request, TR_KEY_tag, &tag))
        tr_variantDictAddInt (&response, TR_KEY_tag, tag);

      buf = tr_variantToBuf (&response, TR_VARIANT_FMT_JSON_LEAN);
      (*callback)(session, buf, callback_user_data);
      evbuffer_free (buf);

      tr_variantFree (&response);
    }
  else if (methods[i].immediate)
    {
      int64_t tag;
      tr_variant response;
      tr_variant * args_out;
      struct evbuffer * buf;

      tr_variantInitDict (&response, 3);
      args_out = tr_variantDictAddDict (&response, TR_KEY_arguments, 0);
      result = (*methods[i].func)(session, args_in, args_out, NULL);
      if (result == NULL)
        result = "success";
      tr_variantDictAddStr (&response, TR_KEY_result, result);
      if (tr_variantDictFindInt (request, TR_KEY_tag, &tag))
        tr_variantDictAddInt (&response, TR_KEY_tag, tag);

      buf = tr_variantToBuf (&response, TR_VARIANT_FMT_JSON_LEAN);
      (*callback)(session, buf, callback_user_data);
      evbuffer_free (buf);

      tr_variantFree (&response);
    }
  else
    {
      int64_t tag;
      struct tr_rpc_idle_data * data = tr_new0 (struct tr_rpc_idle_data, 1);
      data->session = session;
      data->response = tr_new0 (tr_variant, 1);
      tr_variantInitDict (data->response, 3);
      if (tr_variantDictFindInt (request, TR_KEY_tag, &tag))
        tr_variantDictAddInt (data->response, TR_KEY_tag, tag);
      data->args_out = tr_variantDictAddDict (data->response, TR_KEY_arguments, 0);
      data->callback = callback;
      data->callback_user_data = callback_user_data;
      (*methods[i].func)(session, args_in, data->args_out, data);
    }
}

void
tr_rpc_request_exec_json (tr_session            * session,
                          const void            * request_json,
                          int                     request_len,
                          tr_rpc_response_func    callback,
                          void                  * callback_user_data)
{
  tr_variant top;
  int have_content;

  if (request_len < 0)
    request_len = strlen (request_json);

  have_content = !tr_variantFromJson (&top, request_json, request_len);
  request_exec (session, have_content ? &top : NULL, callback, callback_user_data);

  if (have_content)
    tr_variantFree (&top);
}

/**
 * Munge the URI into a usable form.
 *
 * We have very loose typing on this to make the URIs as simple as possible:
 * - anything not a 'tag' or 'method' is automatically in 'arguments'
 * - values that are all-digits are numbers
 * - values that are all-digits or commas are number lists
 * - all other values are strings
 */
void
tr_rpc_parse_list_str (tr_variant  * setme,
                       const char  * str,
                       int           len)

{
  int valueCount;
  int * values = tr_parseNumberRange (str, len, &valueCount);

  if (valueCount == 0)
    {
      tr_variantInitStr (setme, str, len);
    }
  else if (valueCount == 1)
    {
      tr_variantInitInt (setme, values[0]);
    }
  else
    {
      int i;

      tr_variantInitList (setme, valueCount);

      for (i=0; i<valueCount; ++i)
        tr_variantListAddInt (setme, values[i]);
    }

  tr_free (values);
}

void
tr_rpc_request_exec_uri (tr_session           * session,
                         const void           * request_uri,
                         int                    request_len,
                         tr_rpc_response_func   callback,
                         void                 * callback_user_data)
{
  const char * pch;
  tr_variant top;
  tr_variant * args;
  char * request = tr_strndup (request_uri, request_len);

  tr_variantInitDict (&top, 3);
  args = tr_variantDictAddDict (&top, TR_KEY_arguments, 0);

  pch = strchr (request, '?');
  if (!pch) pch = request;
  while (pch)
    {
      const char * delim = strchr (pch, '=');
      const char * next = strchr (pch, '&');
      if (delim)
        {
          char * key = tr_strndup (pch, delim - pch);
          int isArg = strcmp (key, "method") && strcmp (key, "tag");
          tr_variant * parent = isArg ? args : &top;

          tr_rpc_parse_list_str (tr_variantDictAdd (parent, tr_quark_new (key, delim-pch)),
                                 delim + 1,
                                 next ? (size_t)(next - (delim + 1)) : strlen (delim + 1));
          tr_free (key);
        }

      pch = next ? next + 1 : NULL;
    }

  request_exec (session, &top, callback, callback_user_data);

  /* cleanup */
  tr_variantFree (&top);
  tr_free (request);
}