OpenSpace/modules/sync/syncs/torrentsynchronization.cpp

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 * OpenSpace                                                                             *
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 * Copyright (c) 2014-2018                                                               *
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#include <modules/sync/syncs/torrentsynchronization.h>

#include <openspace/documentation/verifier.h>
#include <ghoul/logging/logmanager.h>
#include <ghoul/filesystem/file.h>
#include <ghoul/filesystem/filesystem.h>
#include <ghoul/misc/dictionary.h>
#include <fstream>

namespace {
    constexpr const char* KeyIdentifier = "Identifier";
    constexpr const char* KeyMagnet = "Magnet";
} // namespace

namespace openspace {

documentation::Documentation TorrentSynchronization::Documentation() {
    using namespace openspace::documentation;
    return {
        "TorrentSynchronization",
        "torrent_synchronization",
        {
            {
                KeyIdentifier,
                new StringVerifier,
                Optional::No,
                "A unique identifier for this torrent"
            },
            {
                KeyMagnet,
                new StringVerifier,
                Optional::No,
                "A magnet link identifying the torrent"
            }
        }
    };
}

TorrentSynchronization::TorrentSynchronization(const ghoul::Dictionary& dict,
                                               std::string synchronizationRoot,
                                               TorrentClient& torrentClient)
    : ResourceSynchronization(dict)
    , _synchronizationRoot(std::move(synchronizationRoot))
    , _torrentClient(torrentClient)
{
    documentation::testSpecificationAndThrow(
        Documentation(),
        dict,
        "TorrentSynchronization"
    );

    _identifier = dict.value<std::string>(KeyIdentifier);
    _magnetLink = dict.value<std::string>(KeyMagnet);
}

TorrentSynchronization::~TorrentSynchronization() {
    cancel();
}

std::string TorrentSynchronization::uniformResourceName() const {
    const size_t begin = _magnetLink.find("=urn") + 1;
    const size_t end = _magnetLink.find('&', begin);
    std::string xs = _magnetLink.substr(
        begin,
        (end == std::string::npos) ? end : (end - begin)
    );

    std::transform(
        xs.begin(),
        xs.end(),
        xs.begin(),
        [](char x) { return (x == ':') ? '.' : x; }
    );
    return xs;
}

std::string TorrentSynchronization::directory() {
    ghoul::filesystem::Directory d(
        _synchronizationRoot +
        ghoul::filesystem::FileSystem::PathSeparator +
        "torrent" +
        ghoul::filesystem::FileSystem::PathSeparator +
        _identifier +
        ghoul::filesystem::FileSystem::PathSeparator +
        uniformResourceName()
    );

    return FileSys.absPath(d);
}

void TorrentSynchronization::start() {
    if (_enabled) {
        return;
    }
    begin();

    if (hasSyncFile()) {
        resolve();
    }

    _enabled = true;
    try {
        _torrentId = _torrentClient.addMagnetLink(
            _magnetLink,
            directory(),
            [this](TorrentClient::TorrentProgress p) {
                updateTorrentProgress(p);
            }
        );
    } catch (const TorrentError& e) {
        LERRORC(name(), e.message);
        if (!isResolved()) {
            reject();
        }
    }
}

void TorrentSynchronization::cancel() {
    if (_enabled) {
        _torrentClient.removeTorrent(_torrentId);
        _enabled = false;
        reset();
    }
}

void TorrentSynchronization::clear() {
    cancel();
    // TODO: Remove all files from directory.
}

bool TorrentSynchronization::hasSyncFile() {
    const std::string& path = directory() + ".ossync";
    return FileSys.fileExists(path);
}

void TorrentSynchronization::createSyncFile() {
    const std::string& directoryName = directory();
    const std::string& filepath = directoryName + ".ossync";

    FileSys.createDirectory(directoryName, ghoul::filesystem::FileSystem::Recursive::Yes);

    std::ofstream syncFile(filepath, std::ofstream::out);
    syncFile << "Synchronized";
    syncFile.close();
}

size_t TorrentSynchronization::nSynchronizedBytes() {
    std::lock_guard<std::mutex> g(_progressMutex);
    return _progress.nDownloadedBytes;
}

size_t TorrentSynchronization::nTotalBytes() {
    std::lock_guard<std::mutex> g(_progressMutex);
    return _progress.nTotalBytes;
}

bool TorrentSynchronization::nTotalBytesIsKnown() {
    std::lock_guard<std::mutex> g(_progressMutex);
    return _progress.nTotalBytesKnown;
}

void TorrentSynchronization::updateTorrentProgress(
                                                  TorrentClient::TorrentProgress progress)
{
    std::lock_guard<std::mutex> g(_progressMutex);
    _progress = progress;
    if (progress.finished && (state() == State::Syncing)) {
        createSyncFile();
        resolve();
    }
}

} // namespace openspace