src/download/downloader.cpp

/*
    SPDX-FileCopyrightText: 2005 Joris Guisson <joris.guisson@gmail.com>

    SPDX-License-Identifier: GPL-2.0-or-later
*/
#include "downloader.h"

#include <QFile>
#include <QTextStream>
#include <klocalizedstring.h>

#include "chunkdownload.h"
#include "chunkselector.h"
#include "version.h"
#include "webseed.h"
#include <diskio/chunkmanager.h>
#include <diskio/piecedata.h>
#include <download/piece.h>
#include <interfaces/monitorinterface.h>
#include <peer/accessmanager.h>
#include <peer/badpeerslist.h>
#include <peer/chunkcounter.h>
#include <peer/peer.h>
#include <peer/peerdownloader.h>
#include <peer/peermanager.h>
#include <torrent/torrent.h>
#include <util/array.h>
#include <util/error.h>
#include <util/file.h>
#include <util/functions.h>
#include <util/log.h>
#include <util/sha1hash.h>

namespace bt
{
bool Downloader::use_webseeds = true;

Downloader::Downloader(Torrent &tor, PeerManager &pman, ChunkManager &cman)
    : tor(tor)
    , pman(pman)
    , cman(cman)
    , bytes_downloaded(0)
    , tmon(nullptr)
    , chunk_selector(nullptr)
    , webseed_endgame_mode(false)
{
    webseeds_on = use_webseeds;
    pman.setPieceHandler(this);
    chunk_selector = new ChunkSelector();
    chunk_selector->init(&cman, this, &pman);

    Uint64 total = tor.getTotalSize();
    bytes_downloaded = (total - cman.bytesLeft());
    curr_chunks_downloaded = 0;
    unnecessary_data = 0;

    current_chunks.setAutoDelete(true);

    active_webseed_downloads = 0;
    const QList<QUrl> &urls = tor.getWebSeeds();
    for (const QUrl &u : urls) {
        if (u.scheme() == QLatin1String("http")) {
            WebSeed *ws = new WebSeed(u, false, tor, cman);
            webseeds.append(ws);
            connect(ws, &WebSeed::chunkReady, this, &Downloader::onChunkReady);
            connect(ws, &WebSeed::chunkDownloadStarted, this, &Downloader::chunkDownloadStarted);
            connect(ws, &WebSeed::chunkDownloadFinished, this, &Downloader::chunkDownloadFinished);
        }
    }

    if (webseeds.count() > 0) {
        webseed_range_size = tor.getNumChunks() / webseeds.count();
        if (webseed_range_size == 0)
            webseed_range_size = 1;

        // make sure the range is not to big
        if (webseed_range_size > tor.getNumChunks() / 10)
            webseed_range_size = tor.getNumChunks() / 10;
    } else {
        webseed_range_size = 1;
    }
}

Downloader::~Downloader()
{
    delete chunk_selector;
    qDeleteAll(webseeds);
}

void Downloader::setChunkSelector(ChunkSelectorInterface *csel)
{
    delete chunk_selector;

    if (!csel) // check if a custom one was provided, if not create a default one
        chunk_selector = new ChunkSelector();
    else
        chunk_selector = csel;

    chunk_selector->init(&cman, this, &pman);
}

void Downloader::pieceReceived(const Piece &p)
{
    if (cman.completed())
        return;

    ChunkDownload *cd = current_chunks.find(p.getIndex());
    if (!cd) {
        unnecessary_data += p.getLength();
        Out(SYS_DIO | LOG_DEBUG) << "Unnecessary piece, total unnecessary data : " << BytesToString(unnecessary_data) << endl;
        return;
    }

    bool ok = false;
    if (cd->piece(p, ok)) {
        if (tmon)
            tmon->downloadRemoved(cd);

        if (ok)
            bytes_downloaded += p.getLength();

        if (!finished(cd)) {
            // if the chunk fails don't count the bytes downloaded
            if (cd->getChunk()->getSize() > bytes_downloaded)
                bytes_downloaded = 0;
            else
                bytes_downloaded -= cd->getChunk()->getSize();
            current_chunks.erase(p.getIndex());
        } else {
            current_chunks.erase(p.getIndex());
            for (WebSeed *ws : qAsConst(webseeds)) {
                if (ws->inCurrentRange(p.getIndex()))
                    ws->chunkDownloaded(p.getIndex());
            }
        }
    } else {
        if (ok)
            bytes_downloaded += p.getLength();
    }

    if (!ok) {
        unnecessary_data += p.getLength();
        Out(SYS_DIO | LOG_DEBUG) << "Unnecessary piece, total unnecessary data : " << BytesToString(unnecessary_data) << endl;
    }
}

bool Downloader::endgameMode() const
{
    return current_chunks.count() >= cman.chunksLeft();
}

void Downloader::update()
{
    if (cman.completed())
        return;

    /*
        Normal update should now handle all modes properly.
    */
    normalUpdate();

    // now see if there aren't any timed out pieces
    for (PieceDownloader *pd : qAsConst(piece_downloaders)) {
        pd->checkTimeouts();
    }

    if (use_webseeds) {
        for (WebSeed *ws : qAsConst(webseeds)) {
            ws->update();
        }
    }

    if (isFinished() && webseeds_on) {
        for (WebSeed *ws : qAsConst(webseeds)) {
            ws->cancel();
        }
    }
}

void Downloader::normalUpdate()
{
    for (CurChunkItr j = current_chunks.begin(); j != current_chunks.end(); ++j) {
        ChunkDownload *cd = j->second;
        if (cd->isIdle()) {
            continue;
        } else if (cd->isChoked()) {
            cd->releaseAllPDs();
        } else if (cd->needsToBeUpdated()) {
            cd->update();
        }
    }

    for (PieceDownloader *pd : qAsConst(piece_downloaders)) {
        if (!pd->isChoked()) {
            while (pd->canDownloadChunk()) {
                if (!downloadFrom(pd))
                    break;
                pd->setNearlyDone(false);
            }
        }
    }

    if (use_webseeds) {
        for (WebSeed *ws : qAsConst(webseeds)) {
            if (!ws->busy() && ws->isEnabled() && ws->failedAttempts() < 3) {
                downloadFrom(ws);
            }
        }
    } else if (webseeds_on != use_webseeds) {
        // reset all webseeds, webseeds have been disabled
        webseeds_on = use_webseeds;
        for (WebSeed *ws : qAsConst(webseeds)) {
            if (ws->busy() && ws->isEnabled()) {
                ws->cancel();
            }
        }
    }
}

ChunkDownload *Downloader::selectCD(PieceDownloader *pd, Uint32 n)
{
    ChunkDownload *sel = nullptr;
    Uint32 sel_left = 0xFFFFFFFF;

    for (CurChunkItr j = current_chunks.begin(); j != current_chunks.end(); ++j) {
        ChunkDownload *cd = j->second;
        if (pd->isChoked() || !pd->hasChunk(cd->getChunk()->getIndex()))
            continue;

        if (cd->getNumDownloaders() == n) {
            // lets favor the ones which are nearly finished
            if (!sel || cd->getTotalPieces() - cd->getPiecesDownloaded() < sel_left) {
                sel = cd;
                sel_left = sel->getTotalPieces() - sel->getPiecesDownloaded();
            }
        }
    }
    return sel;
}

bool Downloader::findDownloadForPD(PieceDownloader *pd)
{
    ChunkDownload *sel = nullptr;

    // See if there are ChunkDownload's which need a PieceDownloader
    sel = selectCD(pd, 0);
    if (sel) {
        return sel->assign(pd);
    }

    return false;
}

ChunkDownload *Downloader::selectWorst(PieceDownloader *pd)
{
    ChunkDownload *cdmin = nullptr;
    for (CurChunkItr j = current_chunks.begin(); j != current_chunks.end(); ++j) {
        ChunkDownload *cd = j->second;
        if (!pd->hasChunk(cd->getChunk()->getIndex()) || cd->containsPeer(pd))
            continue;

        if (!cdmin)
            cdmin = cd;
        else if (cd->getDownloadSpeed() < cdmin->getDownloadSpeed())
            cdmin = cd;
        else if (cd->getNumDownloaders() < cdmin->getNumDownloaders())
            cdmin = cd;
    }

    return cdmin;
}

bool Downloader::downloadFrom(PieceDownloader *pd)
{
    // first see if we can use an existing dowload
    if (findDownloadForPD(pd))
        return true;

    Uint32 chunk = 0;
    if (chunk_selector->select(pd, chunk)) {
        Chunk *c = cman.getChunk(chunk);
        if (current_chunks.contains(chunk)) {
            return current_chunks.find(chunk)->assign(pd);
        } else {
            ChunkDownload *cd = new ChunkDownload(c);
            current_chunks.insert(chunk, cd);
            cd->assign(pd);
            if (tmon)
                tmon->downloadStarted(cd);
            return true;
        }
    } else if (pd->getNumGrabbed() == 0) {
        // If the peer hasn't got a chunk we want,
        ChunkDownload *cdmin = selectWorst(pd);

        if (cdmin) {
            return cdmin->assign(pd);
        }
    }

    return false;
}

void Downloader::downloadFrom(WebSeed *ws)
{
    Uint32 first = 0;
    Uint32 last = 0;
    webseed_endgame_mode = false;
    if (chunk_selector->selectRange(first, last, webseed_range_size)) {
        ws->download(first, last);
    } else {
        // go to endgame mode
        webseed_endgame_mode = true;
        if (chunk_selector->selectRange(first, last, webseed_range_size))
            ws->download(first, last);
    }
}

bool Downloader::downloading(Uint32 chunk) const
{
    return current_chunks.find(chunk) != nullptr;
}

bool Downloader::canDownloadFromWebSeed(Uint32 chunk) const
{
    if (webseed_endgame_mode)
        return true;

    for (WebSeed *ws : qAsConst(webseeds)) {
        if (ws->busy() && ws->inCurrentRange(chunk))
            return false;
    }

    return !downloading(chunk);
}

Uint32 Downloader::numDownloadersForChunk(Uint32 chunk) const
{
    const ChunkDownload *cd = current_chunks.find(chunk);
    if (!cd)
        return 0;

    return cd->getNumDownloaders();
}

void Downloader::addPieceDownloader(PieceDownloader *peer)
{
    piece_downloaders.append(peer);
}

void Downloader::removePieceDownloader(PieceDownloader *peer)
{
    for (CurChunkItr i = current_chunks.begin(); i != current_chunks.end(); ++i) {
        ChunkDownload *cd = i->second;
        cd->killed(peer);
    }
    piece_downloaders.removeAll(peer);
}

bool Downloader::finished(ChunkDownload *cd)
{
    Chunk *c = cd->getChunk();
    // verify the data
    SHA1Hash h = cd->getHash();

    if (tor.verifyHash(h, c->getIndex())) {
        // hash ok so save it
        try {
            for (WebSeed *ws : qAsConst(webseeds)) {
                // tell all webseeds a chunk is downloaded
                if (ws->inCurrentRange(c->getIndex()))
                    ws->chunkDownloaded(c->getIndex());
            }

            cman.chunkDownloaded(c->getIndex());
            Out(SYS_GEN | LOG_IMPORTANT) << "Chunk " << c->getIndex() << " downloaded " << endl;
            pman.sendHave(c->getIndex());
            Q_EMIT chunkDownloaded(c->getIndex());
        } catch (Error &e) {
            Out(SYS_DIO | LOG_IMPORTANT) << "Error " << e.toString() << endl;
            Q_EMIT ioError(e.toString());
            return false;
        }
    } else {
        Out(SYS_GEN | LOG_IMPORTANT) << "Hash verification error on chunk " << c->getIndex() << endl;
        Out(SYS_GEN | LOG_IMPORTANT) << "Is        : " << h << endl;
        Out(SYS_GEN | LOG_IMPORTANT) << "Should be : " << tor.getHash(c->getIndex()) << endl;

        // reset chunk but only when no webseeder is downloading it
        if (!webseeds_chunks.find(c->getIndex()))
            cman.resetChunk(c->getIndex());

        chunk_selector->reinsert(c->getIndex());

        PieceDownloader *only = cd->getOnlyDownloader();
        if (only) {
            Peer::Ptr p = pman.findPeer(only);
            if (!p)
                return false;

            QString ip = p->getIPAddresss();
            Out(SYS_GEN | LOG_NOTICE) << "Peer " << ip << " sent bad data" << endl;
            AccessManager::instance().banPeer(ip);
            p->kill();
        }
        return false;
    }
    return true;
}

void Downloader::clearDownloads()
{
    current_chunks.clear();
    piece_downloaders.clear();

    for (WebSeed *ws : qAsConst(webseeds))
        ws->cancel();
}

void Downloader::pause()
{
    if (tmon) {
        for (CurChunkItr i = current_chunks.begin(); i != current_chunks.end(); ++i) {
            ChunkDownload *cd = i->second;
            tmon->downloadRemoved(cd);
        }
    }

    current_chunks.clear();
    for (WebSeed *ws : qAsConst(webseeds))
        ws->reset();
}

Uint32 Downloader::downloadRate() const
{
    // sum of the download rate of each peer
    Uint32 rate = 0;
    for (PieceDownloader *pd : qAsConst(piece_downloaders))
        if (pd)
            rate += pd->getDownloadRate();

    for (WebSeed *ws : qAsConst(webseeds)) {
        rate += ws->getDownloadRate();
    }

    return rate;
}

void Downloader::setMonitor(MonitorInterface *tmo)
{
    tmon = tmo;
    if (!tmon)
        return;

    for (CurChunkItr i = current_chunks.begin(); i != current_chunks.end(); ++i) {
        ChunkDownload *cd = i->second;
        tmon->downloadStarted(cd);
    }

    for (WebSeed *ws : qAsConst(webseeds)) {
        WebSeedChunkDownload *cd = ws->currentChunkDownload();
        if (cd)
            tmon->downloadStarted(cd);
    }
}

void Downloader::saveDownloads(const QString &file)
{
    File fptr;
    if (!fptr.open(file, "wb"))
        return;

    // See bug 219019, don't know why, but it is possible that we get 0 pointers in the map
    // so get rid of them before we save
    for (CurChunkItr i = current_chunks.begin(); i != current_chunks.end();) {
        if (!i->second)
            i = current_chunks.erase(i);
        else
            ++i;
    }

    // Save all the current downloads to a file
    CurrentChunksHeader hdr;
    hdr.magic = CURRENT_CHUNK_MAGIC;
    hdr.major = bt::MAJOR;
    hdr.minor = bt::MINOR;
    hdr.num_chunks = current_chunks.count();
    fptr.write(&hdr, sizeof(CurrentChunksHeader));

    Out(SYS_GEN | LOG_DEBUG) << "Saving " << current_chunks.count() << " chunk downloads" << endl;
    for (CurChunkItr i = current_chunks.begin(); i != current_chunks.end(); ++i) {
        ChunkDownload *cd = i->second;
        cd->save(fptr);
    }
}

void Downloader::loadDownloads(const QString &file)
{
    // don't load stuff if download is finished
    if (cman.completed())
        return;

    // Load all partial downloads
    File fptr;
    if (!fptr.open(file, "rb"))
        return;

    // recalculate downloaded bytes
    bytes_downloaded = (tor.getTotalSize() - cman.bytesLeft());

    CurrentChunksHeader chdr;
    fptr.read(&chdr, sizeof(CurrentChunksHeader));
    if (chdr.magic != CURRENT_CHUNK_MAGIC) {
        Out(SYS_GEN | LOG_DEBUG) << "Warning : current_chunks file corrupted" << endl;
        return;
    }

    Out(SYS_GEN | LOG_DEBUG) << "Loading " << chdr.num_chunks << " active chunk downloads" << endl;
    for (Uint32 i = 0; i < chdr.num_chunks; i++) {
        ChunkDownloadHeader hdr;
        // first read header
        fptr.read(&hdr, sizeof(ChunkDownloadHeader));
        Out(SYS_GEN | LOG_DEBUG) << "Loading chunk " << hdr.index << endl;
        if (hdr.index >= tor.getNumChunks()) {
            Out(SYS_GEN | LOG_DEBUG) << "Warning : current_chunks file corrupted, invalid index " << hdr.index << endl;
            return;
        }

        Chunk *c = cman.getChunk(hdr.index);
        if (!c || current_chunks.contains(hdr.index)) {
            Out(SYS_GEN | LOG_DEBUG) << "Illegal chunk " << hdr.index << endl;
            return;
        }

        ChunkDownload *cd = new ChunkDownload(c);
        bool ret = false;
        try {
            ret = cd->load(fptr, hdr);
        } catch (...) {
            ret = false;
        }

        if (!ret || c->getStatus() == Chunk::ON_DISK || c->isExcluded()) {
            delete cd;
        } else {
            current_chunks.insert(hdr.index, cd);
            bytes_downloaded += cd->bytesDownloaded();

            if (tmon)
                tmon->downloadStarted(cd);
        }
    }

    // reset curr_chunks_downloaded to 0
    curr_chunks_downloaded = 0;
}

Uint32 Downloader::getDownloadedBytesOfCurrentChunksFile(const QString &file)
{
    // Load all partial downloads
    File fptr;
    if (!fptr.open(file, "rb"))
        return 0;

    // read the number of chunks
    CurrentChunksHeader chdr;
    fptr.read(&chdr, sizeof(CurrentChunksHeader));
    if (chdr.magic != CURRENT_CHUNK_MAGIC) {
        Out(SYS_GEN | LOG_DEBUG) << "Warning : current_chunks file corrupted" << endl;
        return 0;
    }
    Uint32 num_bytes = 0;

    // load all chunks and calculate how much is downloaded
    for (Uint32 i = 0; i < chdr.num_chunks; i++) {
        // read the chunkdownload header
        ChunkDownloadHeader hdr;
        fptr.read(&hdr, sizeof(ChunkDownloadHeader));

        Chunk *c = cman.getChunk(hdr.index);
        if (!c)
            return num_bytes;

        ChunkDownload tmp(c);
        if (!tmp.load(fptr, hdr, false))
            return num_bytes;

        num_bytes += tmp.bytesDownloaded();
    }
    curr_chunks_downloaded = num_bytes;
    return num_bytes;
}

bool Downloader::isFinished() const
{
    return cman.completed();
}

void Downloader::onExcluded(Uint32 from, Uint32 to)
{
    for (Uint32 i = from; i <= to; i++) {
        ChunkDownload *cd = current_chunks.find(i);
        if (!cd)
            continue;

        cd->cancelAll();
        cd->releaseAllPDs();
        if (tmon)
            tmon->downloadRemoved(cd);
        current_chunks.erase(i);
        cman.resetChunk(i); // reset chunk it is not fully downloaded yet
    }

    for (WebSeed *ws : qAsConst(webseeds)) {
        ws->onExcluded(from, to);
    }
}

void Downloader::onIncluded(Uint32 from, Uint32 to)
{
    chunk_selector->reincluded(from, to);
}

void Downloader::corrupted(Uint32 chunk)
{
    chunk_selector->reinsert(chunk);
}

void Downloader::dataChecked(const bt::BitSet &ok_chunks, Uint32 from, Uint32 to)
{
    for (Uint32 i = from; i < ok_chunks.getNumBits() && i <= to; i++) {
        ChunkDownload *cd = current_chunks.find(i);
        if (ok_chunks.get(i) && cd) {
            // we have a chunk and we are downloading it so kill it
            cd->releaseAllPDs();
            if (tmon)
                tmon->downloadRemoved(cd);

            current_chunks.erase(i);
        }
    }
    chunk_selector->dataChecked(ok_chunks, from, to);
}

void Downloader::recalcDownloaded()
{
    Uint64 total = tor.getTotalSize();
    bytes_downloaded = (total - cman.bytesLeft());
}

void Downloader::onChunkReady(Chunk *c)
{
    WebSeed *ws = webseeds_chunks.find(c->getIndex());
    webseeds_chunks.erase(c->getIndex());
    PieceData::Ptr piece = c->getPiece(0, c->getSize(), true);
    if (piece && c->checkHash(tor.getHash(c->getIndex()))) {
        // hash ok so save it
        try {
            bytes_downloaded += c->getSize();

            for (WebSeed *ws : qAsConst(webseeds)) {
                // tell all webseeds a chunk is downloaded
                if (ws->inCurrentRange(c->getIndex()))
                    ws->chunkDownloaded(c->getIndex());
            }

            ChunkDownload *cd = current_chunks.find(c->getIndex());
            if (cd) {
                // A ChunkDownload is ongoing for this chunk so kill it, we have the chunk
                cd->cancelAll();
                if (tmon)
                    tmon->downloadRemoved(cd);
                current_chunks.erase(c->getIndex());
            }

            c->savePiece(piece);
            cman.chunkDownloaded(c->getIndex());

            Out(SYS_GEN | LOG_IMPORTANT) << "Chunk " << c->getIndex() << " downloaded via webseed ! " << endl;
            // tell everybody we have the Chunk
            pman.sendHave(c->getIndex());
        } catch (Error &e) {
            Out(SYS_DIO | LOG_IMPORTANT) << "Error " << e.toString() << endl;
            Q_EMIT ioError(e.toString());
        }
    } else {
        Out(SYS_GEN | LOG_IMPORTANT) << "Hash verification error on chunk " << c->getIndex() << endl;
        // reset chunk but only when no other peer is downloading it
        if (!current_chunks.find(c->getIndex()))
            cman.resetChunk(c->getIndex());

        chunk_selector->reinsert(c->getIndex());
        ws->disable(i18n("Disabled because webseed does not match torrent"));
    }
}

void Downloader::chunkDownloadStarted(WebSeedChunkDownload *cd, Uint32 chunk)
{
    webseeds_chunks.insert(chunk, cd->ws);
    active_webseed_downloads++;
    if (tmon)
        tmon->downloadStarted(cd);
}

void Downloader::chunkDownloadFinished(WebSeedChunkDownload *cd, Uint32 chunk)
{
    webseeds_chunks.erase(chunk);
    if (active_webseed_downloads > 0)
        active_webseed_downloads--;

    if (tmon)
        tmon->downloadRemoved(cd);
}

WebSeed *Downloader::addWebSeed(const QUrl &url)
{
    // Check for dupes
    for (WebSeed *ws : qAsConst(webseeds)) {
        if (ws->getUrl() == url)
            return nullptr;
    }

    WebSeed *ws = new WebSeed(url, true, tor, cman);
    webseeds.append(ws);
    connect(ws, &WebSeed::chunkReady, this, &Downloader::onChunkReady);
    connect(ws, &WebSeed::chunkDownloadStarted, this, &Downloader::chunkDownloadStarted);
    connect(ws, &WebSeed::chunkDownloadFinished, this, &Downloader::chunkDownloadFinished);
    return ws;
}

bool Downloader::removeWebSeed(const QUrl &url)
{
    for (WebSeed *ws : qAsConst(webseeds)) {
        if (ws->getUrl() == url && ws->isUserCreated()) {
            PtrMap<Uint32, WebSeed>::iterator i = webseeds_chunks.begin();
            while (i != webseeds_chunks.end()) {
                if (i->second == ws)
                    i = webseeds_chunks.erase(i);
                else
                    ++i;
            }
            webseeds.removeAll(ws);
            delete ws;
            return true;
        }
    }
    return false;
}

void Downloader::removeAllWebSeeds()
{
    webseeds.clear();
    webseeds_chunks.clear();
}

void Downloader::saveWebSeeds(const QString &file)
{
    QFile fptr(file);
    if (!fptr.open(QIODevice::WriteOnly)) {
        Out(SYS_GEN | LOG_NOTICE) << "Cannot open " << file << " to save webseeds" << endl;
        return;
    }

    QTextStream out(&fptr);
    for (WebSeed *ws : qAsConst(webseeds)) {
        if (ws->isUserCreated())
            out << ws->getUrl().toDisplayString() << Qt::endl;
    }
    out << "====disabled====" << Qt::endl;
    for (WebSeed *ws : qAsConst(webseeds)) {
        if (!ws->isEnabled())
            out << ws->getUrl().toDisplayString() << Qt::endl;
    }
}

void Downloader::loadWebSeeds(const QString &file)
{
    QFile fptr(file);
    if (!fptr.open(QIODevice::ReadOnly)) {
        Out(SYS_GEN | LOG_NOTICE) << "Cannot open " << file << " to load webseeds" << endl;
        return;
    }

    bool disabled_list_found = false;
    QTextStream in(&fptr);
    while (!in.atEnd()) {
        QString line = in.readLine();
        if (line == QLatin1String("====disabled====")) {
            disabled_list_found = true;
            continue;
        }

        QUrl url(line);
        if (!url.isValid() || url.scheme() != QLatin1String("http"))
            continue;

        if (disabled_list_found) {
            for (WebSeed *ws : qAsConst(webseeds)) {
                if (ws->getUrl() == url) {
                    ws->setEnabled(false);
                    break;
                }
            }
        } else {
            WebSeed *ws = new WebSeed(url, true, tor, cman);
            webseeds.append(ws);
            connect(ws, &WebSeed::chunkReady, this, &Downloader::onChunkReady);
            connect(ws, &WebSeed::chunkDownloadStarted, this, &Downloader::chunkDownloadStarted);
            connect(ws, &WebSeed::chunkDownloadFinished, this, &Downloader::chunkDownloadFinished);
        }
    }
}

void Downloader::setGroupIDs(Uint32 up, Uint32 down)
{
    for (WebSeed *ws : qAsConst(webseeds)) {
        ws->setGroupIDs(up, down);
    }
}

ChunkDownload *Downloader::download(Uint32 chunk)
{
    return current_chunks.find(chunk);
}

const bt::ChunkDownload *Downloader::download(Uint32 chunk) const
{
    return current_chunks.find(chunk);
}

void Downloader::setUseWebSeeds(bool on)
{
    use_webseeds = on;
}
}