/*
 * This file Copyright (C) Mnemosyne LLC
 *
 * This file is licensed by the GPL version 2. Works owned by the
 * Transmission project are granted a special exemption to clause 2 (b)
 * so that the bulk of its code can remain under the MIT license.
 * This exemption does not extend to derived works not owned by
 * the Transmission project.
 *
 * $Id$
 */

#include <errno.h> /* EINVAL */
#include "transmission.h"
#include "magnet.h"
#include "session.h" /* tr_sessionFindTorrentFile () */
#include "torrent.h" /* tr_ctorGetSave () */
#include "utils.h" /* tr_new0 */
#include "variant.h"

struct optional_args
{
    bool            isSet_paused;
    bool            isSet_connected;
    bool            isSet_downloadDir;

    bool            isPaused;
    uint16_t        peerLimit;
    char          * downloadDir;
};

/** Opaque class used when instantiating torrents.
 * @ingroup tr_ctor */
struct tr_ctor
{
    const tr_session *      session;
    bool                    saveInOurTorrentsDir;
    bool                    doDelete;

    tr_priority_t           bandwidthPriority;
    bool                    isSet_metainfo;
    bool                    isSet_delete;
    tr_variant              metainfo;
    char *                  sourceFile;

    struct optional_args    optionalArgs[2];

    char                  * cookies;
    char                  * incompleteDir;

    tr_file_index_t       * want;
    tr_file_index_t         wantSize;
    tr_file_index_t       * notWant;
    tr_file_index_t         notWantSize;
    tr_file_index_t       * low;
    tr_file_index_t         lowSize;
    tr_file_index_t       * normal;
    tr_file_index_t         normalSize;
    tr_file_index_t       * high;
    tr_file_index_t         highSize;
};

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

static void
setSourceFile (tr_ctor *    ctor,
               const char * sourceFile)
{
    tr_free (ctor->sourceFile);
    ctor->sourceFile = tr_strdup (sourceFile);
}

static void
clearMetainfo (tr_ctor * ctor)
{
    if (ctor->isSet_metainfo)
    {
        ctor->isSet_metainfo = false;
        tr_variantFree (&ctor->metainfo);
    }

    setSourceFile (ctor, NULL);
}

int
tr_ctorSetMetainfo (tr_ctor *       ctor,
                    const uint8_t * metainfo,
                    size_t          len)
{
    int err;

    clearMetainfo (ctor);
    err = tr_variantFromBenc (&ctor->metainfo, metainfo, len);
    ctor->isSet_metainfo = !err;
    return err;
}

const char*
tr_ctorGetSourceFile (const tr_ctor * ctor)
{
    return ctor->sourceFile;
}

int
tr_ctorSetMetainfoFromMagnetLink (tr_ctor * ctor, const char * magnet_link)
{
    int err;
    tr_magnet_info * magnet_info = tr_magnetParse (magnet_link);

    if (magnet_info == NULL)
        err = -1;
    else {
        int len;
        tr_variant tmp;
        char * str;

        tr_magnetCreateMetainfo (magnet_info, &tmp);
        str = tr_variantToStr (&tmp, TR_VARIANT_FMT_BENC, &len);
        err = tr_ctorSetMetainfo (ctor, (const uint8_t*)str, len);

        tr_free (str);
        tr_variantFree (&tmp);
        tr_magnetFree (magnet_info);
    }

    return err;
}

int
tr_ctorSetMetainfoFromFile (tr_ctor *    ctor,
                            const char * filename)
{
    uint8_t * metainfo;
    size_t    len;
    int       err;

    metainfo = tr_loadFile (filename, &len);
    if (metainfo && len)
        err = tr_ctorSetMetainfo (ctor, metainfo, len);
    else
    {
        clearMetainfo (ctor);
        err = 1;
    }

    setSourceFile (ctor, filename);

    /* if no `name' field was set, then set it from the filename */
    if (ctor->isSet_metainfo)
    {
        tr_variant * info;
        if (tr_variantDictFindDict (&ctor->metainfo, TR_KEY_info, &info))
        {
            const char * name;
            if (!tr_variantDictFindStr (info, TR_KEY_name_utf_8, &name, NULL))
                if (!tr_variantDictFindStr (info, TR_KEY_name, &name, NULL))
                    name = NULL;
            if (!name || !*name)
            {
                char * base = tr_basename (filename);
                tr_variantDictAddStr (info, TR_KEY_name, base);
                tr_free (base);
            }
        }
    }

    tr_free (metainfo);
    return err;
}

int
tr_ctorSetMetainfoFromHash (tr_ctor *    ctor,
                            const char * hashString)
{
    int          err;
    const char * filename;

    filename = tr_sessionFindTorrentFile (ctor->session, hashString);
    if (!filename)
        err = EINVAL;
    else
        err = tr_ctorSetMetainfoFromFile (ctor, filename);

    return err;
}

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

void
tr_ctorSetFilePriorities (tr_ctor                * ctor,
                          const tr_file_index_t  * files,
                          tr_file_index_t          fileCount,
                          tr_priority_t            priority)
{
    tr_file_index_t ** myfiles;
    tr_file_index_t * mycount;

    switch (priority) {
        case TR_PRI_LOW: myfiles = &ctor->low; mycount = &ctor->lowSize; break;
        case TR_PRI_HIGH: myfiles = &ctor->high; mycount = &ctor->highSize; break;
        default /*TR_PRI_NORMAL*/: myfiles = &ctor->normal; mycount = &ctor->normalSize; break;
    }

    tr_free (*myfiles);
    *myfiles = tr_memdup (files, sizeof (tr_file_index_t)*fileCount);
    *mycount = fileCount;
}

void
tr_ctorInitTorrentPriorities (const tr_ctor * ctor, tr_torrent * tor)
{
    tr_file_index_t i;

    for (i=0; i<ctor->lowSize; ++i)
        tr_torrentInitFilePriority (tor, ctor->low[i], TR_PRI_LOW);
    for (i=0; i<ctor->normalSize; ++i)
        tr_torrentInitFilePriority (tor, ctor->normal[i], TR_PRI_NORMAL);
    for (i=0; i<ctor->highSize; ++i)
        tr_torrentInitFilePriority (tor, ctor->high[i], TR_PRI_HIGH);
}

void
tr_ctorSetFilesWanted (tr_ctor                * ctor,
                       const tr_file_index_t  * files,
                       tr_file_index_t          fileCount,
                       bool                     wanted)
{
    tr_file_index_t ** myfiles = wanted ? &ctor->want : &ctor->notWant;
    tr_file_index_t * mycount = wanted ? &ctor->wantSize : &ctor->notWantSize;

    tr_free (*myfiles);
    *myfiles = tr_memdup (files, sizeof (tr_file_index_t)*fileCount);
    *mycount = fileCount;
}

void
tr_ctorInitTorrentWanted (const tr_ctor * ctor, tr_torrent * tor)
{
    if (ctor->notWantSize)
        tr_torrentInitFileDLs (tor, ctor->notWant, ctor->notWantSize, false);
    if (ctor->wantSize)
        tr_torrentInitFileDLs (tor, ctor->want, ctor->wantSize, true);
}

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

void
tr_ctorSetDeleteSource (tr_ctor * ctor, bool deleteSource)
{
    assert (tr_isBool (deleteSource));

    ctor->doDelete = deleteSource;
    ctor->isSet_delete = true;
}

int
tr_ctorGetDeleteSource (const tr_ctor * ctor, bool * setme)
{
    int err = 0;

    if (!ctor->isSet_delete)
        err = 1;
    else if (setme)
        *setme = ctor->doDelete ? 1 : 0;

    return err;
}

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

void
tr_ctorSetSave (tr_ctor * ctor, bool saveInOurTorrentsDir)
{
    assert (tr_isBool (saveInOurTorrentsDir));

    ctor->saveInOurTorrentsDir = saveInOurTorrentsDir;
}

int
tr_ctorGetSave (const tr_ctor * ctor)
{
    return ctor && ctor->saveInOurTorrentsDir;
}

void
tr_ctorSetPaused (tr_ctor *   ctor,
                  tr_ctorMode mode,
                  bool        isPaused)
{
    struct optional_args * args;

    assert (ctor != NULL);
    assert ((mode == TR_FALLBACK) || (mode == TR_FORCE));
    assert (tr_isBool (isPaused));

    args = &ctor->optionalArgs[mode];
    args->isSet_paused = true;
    args->isPaused = isPaused;
}

void
tr_ctorSetPeerLimit (tr_ctor *   ctor,
                     tr_ctorMode mode,
                     uint16_t    peerLimit)
{
    struct optional_args * args;

    assert (ctor != NULL);
    assert ((mode == TR_FALLBACK) || (mode == TR_FORCE));

    args = &ctor->optionalArgs[mode];
    args->isSet_connected = true;
    args->peerLimit = peerLimit;
}

void
tr_ctorSetDownloadDir (tr_ctor *    ctor,
                       tr_ctorMode  mode,
                       const char * directory)
{
    struct optional_args * args;

    assert (ctor != NULL);
    assert ((mode == TR_FALLBACK) || (mode == TR_FORCE));

    args = &ctor->optionalArgs[mode];
    tr_free (args->downloadDir);
    args->downloadDir = NULL;
    args->isSet_downloadDir = false;

    if (directory && *directory)
    {
        args->isSet_downloadDir = true;
        args->downloadDir = tr_strdup (directory);
    }
}

void
tr_ctorSetIncompleteDir (tr_ctor * ctor, const char * directory)
{
    tr_free (ctor->incompleteDir);
    ctor->incompleteDir = tr_strdup (directory);
}

int
tr_ctorGetPeerLimit (const tr_ctor * ctor,
                     tr_ctorMode     mode,
                     uint16_t *      setmeCount)
{
    int err = 0;
    const struct optional_args * args = &ctor->optionalArgs[mode];

    if (!args->isSet_connected)
        err = 1;
    else if (setmeCount)
        *setmeCount = args->peerLimit;

    return err;
}

int
tr_ctorGetPaused (const tr_ctor * ctor, tr_ctorMode mode, bool * setmeIsPaused)
{
    int err = 0;
    const struct optional_args * args = &ctor->optionalArgs[mode];

    if (!args->isSet_paused)
        err = 1;
    else if (setmeIsPaused)
        *setmeIsPaused = args->isPaused;

    return err;
}

int
tr_ctorGetDownloadDir (const tr_ctor * ctor,
                       tr_ctorMode     mode,
                       const char **   setmeDownloadDir)
{
    int err = 0;
    const struct optional_args * args = &ctor->optionalArgs[mode];

    if (!args->isSet_downloadDir)
        err = 1;
    else if (setmeDownloadDir)
        *setmeDownloadDir = args->downloadDir;

    return err;
}

int
tr_ctorGetIncompleteDir (const tr_ctor  * ctor,
                         const char    ** setmeIncompleteDir)
{
    int err = 0;

    if (ctor->incompleteDir == NULL)
        err = 1;
    else
        *setmeIncompleteDir = ctor->incompleteDir;

    return err;
}

int
tr_ctorGetMetainfo (const tr_ctor *  ctor,
                    const tr_variant ** setme)
{
    int err = 0;

    if (!ctor->isSet_metainfo)
        err = 1;
    else if (setme)
        *setme = &ctor->metainfo;

    return err;
}

tr_session*
tr_ctorGetSession (const tr_ctor * ctor)
{
    return (tr_session*) ctor->session;
}

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

static bool
isPriority (int i)
{
    return (i==TR_PRI_LOW) || (i==TR_PRI_NORMAL) || (i==TR_PRI_HIGH);
}

void
tr_ctorSetBandwidthPriority (tr_ctor * ctor, tr_priority_t priority)
{
    if (isPriority (priority))
        ctor->bandwidthPriority = priority;
}

tr_priority_t
tr_ctorGetBandwidthPriority (const tr_ctor * ctor)
{
    return ctor->bandwidthPriority;
}

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

tr_ctor*
tr_ctorNew (const tr_session * session)
{
    tr_ctor * ctor = tr_new0 (struct tr_ctor, 1);

    ctor->session = session;
    ctor->bandwidthPriority = TR_PRI_NORMAL;
    if (session != NULL)
    {
        tr_ctorSetDeleteSource (ctor, tr_sessionGetDeleteSource (session));
        tr_ctorSetPaused (ctor, TR_FALLBACK, tr_sessionGetPaused (session));
        tr_ctorSetPeerLimit (ctor, TR_FALLBACK, session->peerLimitPerTorrent);
        tr_ctorSetDownloadDir (ctor, TR_FALLBACK, tr_sessionGetDownloadDir(session));
    }
    tr_ctorSetSave (ctor, true);
    return ctor;
}

void
tr_ctorFree (tr_ctor * ctor)
{
    clearMetainfo (ctor);
    tr_free (ctor->optionalArgs[1].downloadDir);
    tr_free (ctor->optionalArgs[0].downloadDir);
    tr_free (ctor->incompleteDir);
    tr_free (ctor->want);
    tr_free (ctor->notWant);
    tr_free (ctor->low);
    tr_free (ctor->high);
    tr_free (ctor->normal);
    tr_free (ctor);
}