/**************************************************************************
**
** This file is part of Qt Creator
**
** Copyright (c) 2012 Nokia Corporation and/or its subsidiary(-ies).
**
** Contact: http://www.qt-project.org/
**
**
** GNU Lesser General Public License Usage
**
** This file may be used under the terms of the GNU Lesser General Public
** License version 2.1 as published by the Free Software Foundation and
** appearing in the file LICENSE.LGPL included in the packaging of this file.
** Please review the following information to ensure the GNU Lesser General
** Public License version 2.1 requirements will be met:
** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** In addition, as a special exception, Nokia gives you certain additional
** rights. These rights are described in the Nokia Qt LGPL Exception
** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
**
** Other Usage
**
** Alternatively, this file may be used in accordance with the terms and
** conditions contained in a signed written agreement between you and Nokia.
**
**
**************************************************************************/

#include "sftpchannel.h"
#include "sftpchannel_p.h"

#include "sftpdefs.h"
#include "sshexception_p.h"
#include "sshincomingpacket_p.h"
#include "sshlogging_p.h"
#include "sshsendfacility_p.h"

#include <QDir>
#include <QFile>

namespace QSsh {
namespace Internal {

namespace {
    const quint32 ProtocolVersion = 3;

    QString errorMessage(const QString &serverMessage,
        const QString &alternativeMessage)
    {
        return serverMessage.isEmpty() ? alternativeMessage : serverMessage;
    }

    QString errorMessage(const SftpStatusResponse &response,
        const QString &alternativeMessage)
    {
        return response.status == SSH_FX_OK ? QString()
            : errorMessage(response.errorString, alternativeMessage);
    }

    bool openFile(QFile *localFile, SftpOverwriteMode mode)
    {
        if (mode == SftpSkipExisting && localFile->exists())
            return false;

        QIODevice::OpenMode openMode = QIODevice::WriteOnly;
        if (mode == SftpOverwriteExisting)
            openMode |= QIODevice::Truncate;
        else if (mode == SftpAppendToExisting)
            openMode |= QIODevice::Append;

        return localFile->open(openMode);
    }

    SftpError sftpStatusToError(const SftpStatusCode status)
    {
        switch (status) {
        case SSH_FX_OK:
            return SftpError::NoError;
        case SSH_FX_EOF:
            return SftpError::EndOfFile;
        case SSH_FX_NO_SUCH_FILE:
            return SftpError::FileNotFound;
        case SSH_FX_PERMISSION_DENIED:
            return SftpError::PermissionDenied;
        case SSH_FX_BAD_MESSAGE:
            return SftpError::BadMessage;
        case SSH_FX_NO_CONNECTION:
            return SftpError::NoConnection;
        case SSH_FX_CONNECTION_LOST:
            return SftpError::ConnectionLost;
        case SSH_FX_OP_UNSUPPORTED:
            return SftpError::UnsupportedOperation;
        case SSH_FX_FAILURE:
        default:
            return SftpError::GenericFailure;
        }
    }

} // anonymous namespace
} // namespace Internal

//--------------------------------------------------------------------------------------------------
// SftpChannel
//--------------------------------------------------------------------------------------------------

SftpChannel::SftpChannel(quint32 channelId,
    Internal::SshSendFacility &sendFacility)
    : d(new Internal::SftpChannelPrivate(channelId, sendFacility, this))
{
    connect(d, &Internal::SftpChannelPrivate::initialized,
            this, &SftpChannel::initialized, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::channelError,
            this, &SftpChannel::channelError, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::dataAvailable,
            this, &SftpChannel::dataAvailable, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::fileInfoAvailable,
            this, &SftpChannel::fileInfoAvailable, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::finished,
            this, &SftpChannel::finished, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::closed,
            this, &SftpChannel::closed, Qt::QueuedConnection);
    connect(d, &Internal::SftpChannelPrivate::transferProgress,
            this, &SftpChannel::transferProgress, Qt::QueuedConnection);
}

SftpChannel::State SftpChannel::state() const
{
    switch (d->channelState()) {
    case Internal::AbstractSshChannel::Inactive:
        return Uninitialized;
    case Internal::AbstractSshChannel::SessionRequested:
        return Initializing;
    case Internal::AbstractSshChannel::CloseRequested:
        return Closing;
    case Internal::AbstractSshChannel::Closed:
        return Closed;
    case Internal::AbstractSshChannel::SessionEstablished:
        return d->m_sftpState == Internal::SftpChannelPrivate::Initialized
            ? Initialized : Initializing;
    default:
        Q_ASSERT(!"Oh no, we forgot to handle a channel state!");
        return Closed; // For the compiler.
    }
}

void SftpChannel::initialize()
{
    d->requestSessionStart();
    d->m_sftpState = Internal::SftpChannelPrivate::SubsystemRequested;
}

void SftpChannel::closeChannel()
{
    d->closeChannel();
}

SftpJobId SftpChannel::statFile(const QString &path)
{
    return d->createJob(Internal::SftpStatFile::Ptr(
        new Internal::SftpStatFile(++d->m_nextJobId, path)));
}

SftpJobId SftpChannel::listDirectory(const QString &path)
{
    return d->createJob(Internal::SftpListDir::Ptr(
        new Internal::SftpListDir(++d->m_nextJobId, path)));
}

SftpJobId SftpChannel::createDirectory(const QString &path)
{
    return d->createJob(Internal::SftpMakeDir::Ptr(
        new Internal::SftpMakeDir(++d->m_nextJobId, path)));
}

SftpJobId SftpChannel::removeDirectory(const QString &path)
{
    return d->createJob(Internal::SftpRmDir::Ptr(
        new Internal::SftpRmDir(++d->m_nextJobId, path)));
}

SftpJobId SftpChannel::removeFile(const QString &path)
{
    return d->createJob(Internal::SftpRm::Ptr(
        new Internal::SftpRm(++d->m_nextJobId, path)));
}

SftpJobId SftpChannel::renameFileOrDirectory(const QString &oldPath,
    const QString &newPath)
{
    return d->createJob(Internal::SftpRename::Ptr(
        new Internal::SftpRename(++d->m_nextJobId, oldPath, newPath)));
}

SftpJobId SftpChannel::createLink(const QString &filePath, const QString &target)
{
    return d->createJob(Internal::SftpCreateLink::Ptr(
        new Internal::SftpCreateLink(++d->m_nextJobId, filePath, target)));
}

SftpJobId SftpChannel::createFile(const QString &path, SftpOverwriteMode mode)
{
    return d->createJob(Internal::SftpCreateFile::Ptr(
        new Internal::SftpCreateFile(++d->m_nextJobId, path, mode)));
}

SftpJobId SftpChannel::uploadFile(QSharedPointer<QIODevice> device,
    const QString &remoteFilePath, SftpOverwriteMode mode)
{
    if (!device->isOpen() && !device->open(QIODevice::ReadOnly))
        return SftpInvalidJob;
    return d->createJob(Internal::SftpUploadFile::Ptr(
        new Internal::SftpUploadFile(++d->m_nextJobId, remoteFilePath, device, mode)));
}

SftpJobId SftpChannel::uploadFile(const QString &localFilePath,
    const QString &remoteFilePath, SftpOverwriteMode mode)
{
    QSharedPointer<QFile> localFile(new QFile(localFilePath));
    if (!localFile->open(QIODevice::ReadOnly))
        return SftpInvalidJob;
    return d->createJob(Internal::SftpUploadFile::Ptr(
        new Internal::SftpUploadFile(++d->m_nextJobId, remoteFilePath, localFile, mode)));
}

SftpJobId SftpChannel::downloadFile(const QString &remoteFilePath,
    const QString &localFilePath, SftpOverwriteMode mode)
{
    QSharedPointer<QFile> localFile(new QFile(localFilePath));
    return d->createJob(Internal::SftpDownload::Ptr(
        new Internal::SftpDownload(++d->m_nextJobId, remoteFilePath, localFile, mode)));
}

SftpJobId SftpChannel::downloadFile(const QString &remoteFilePath, QSharedPointer<QIODevice> device)
{
    return d->createJob(Internal::SftpDownload::Ptr(
        new Internal::SftpDownload(++d->m_nextJobId, remoteFilePath, device, SftpOverwriteExisting)));
}

SftpJobId SftpChannel::uploadDir(const QString &localDirPath,
    const QString &remoteParentDirPath)
{
    if (state() != Initialized)
        return SftpInvalidJob;
    const QDir localDir(localDirPath);
    if (!localDir.exists() || !localDir.isReadable())
        return SftpInvalidJob;
    const Internal::SftpUploadDir::Ptr uploadDirOp(
        new Internal::SftpUploadDir(++d->m_nextJobId));
    const QString remoteDirPath
        = remoteParentDirPath + u'/' + localDir.dirName();
    const Internal::SftpMakeDir::Ptr mkdirOp(
        new Internal::SftpMakeDir(++d->m_nextJobId, remoteDirPath, uploadDirOp));
    uploadDirOp->mkdirsInProgress.insert(mkdirOp,
        Internal::SftpUploadDir::Dir(localDirPath, remoteDirPath));
    d->createJob(mkdirOp);
    return uploadDirOp->jobId;
}

SftpJobId SftpChannel::downloadDir(const QString &remoteDirPath,
    const QString &localDirPath, SftpOverwriteMode mode)
{
    if (state() != Initialized)
        return SftpInvalidJob;
    if (!QDir().mkpath(localDirPath))
        return SftpInvalidJob;
    const Internal::SftpDownloadDir::Ptr downloadDirOp(
        new Internal::SftpDownloadDir(++d->m_nextJobId, mode));
    const Internal::SftpListDir::Ptr lsdirOp(
        new Internal::SftpListDir(++d->m_nextJobId, remoteDirPath, downloadDirOp));
    downloadDirOp->lsdirsInProgress.insert(lsdirOp,
       Internal::SftpDownloadDir::Dir(localDirPath, remoteDirPath));
    d->createJob(lsdirOp);
    return downloadDirOp->jobId;
}

SftpChannel::~SftpChannel()
{
    delete d;
}

//--------------------------------------------------------------------------------------------------
// SftpChannelPrivate
//--------------------------------------------------------------------------------------------------

namespace Internal {

SftpChannelPrivate::SftpChannelPrivate(quint32 channelId,
    SshSendFacility &sendFacility, SftpChannel *sftp)
    : AbstractSshChannel(channelId, sendFacility),
      m_nextJobId(0), m_sftpState(Inactive), m_sftp(sftp)
{
}

SftpJobId SftpChannelPrivate::createJob(const AbstractSftpOperation::Ptr &job)
{
   if (m_sftp->state() != SftpChannel::Initialized)
       return SftpInvalidJob;
   m_jobs.insert(job->jobId, job);
   sendData(job->initialPacket(m_outgoingPacket).rawData());
   return job->jobId;
}

void SftpChannelPrivate::handleChannelSuccess()
{
    if (channelState() == CloseRequested)
        return;
    qCDebug(sshLog, "sftp subsystem initialized");
    sendData(m_outgoingPacket.generateInit(ProtocolVersion).rawData());
    m_sftpState = InitSent;
}

void SftpChannelPrivate::handleChannelFailure()
{
    if (channelState() == CloseRequested)
        return;

    if (m_sftpState != SubsystemRequested) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_MSG_CHANNEL_FAILURE packet.");
    }
    emit channelError(tr("Server could not start SFTP subsystem."));
    closeChannel();
}

void SftpChannelPrivate::handleChannelDataInternal(const QByteArray &data)
{
    if (channelState() == CloseRequested)
        return;

    m_incomingData += data;
    m_incomingPacket.consumeData(m_incomingData);
    while (m_incomingPacket.isComplete()) {
        handleCurrentPacket();
        m_incomingPacket.clear();
        m_incomingPacket.consumeData(m_incomingData);
    }
}

void SftpChannelPrivate::handleChannelExtendedDataInternal(quint32 type,
    const QByteArray &data)
{
    qCWarning(sshLog, "Unexpected extended data '%s' of type %d on SFTP channel.",
              data.data(), type);
}

void SftpChannelPrivate::handleExitStatus(const SshChannelExitStatus &exitStatus)
{
    qCDebug(sshLog, "Remote SFTP service exited with exit code %d", exitStatus.exitStatus);

    if (channelState() == CloseRequested || channelState() == Closed)
        return;

    emit channelError(tr("The SFTP server finished unexpectedly with exit code %1.")
                      .arg(exitStatus.exitStatus));

    // Note: According to the specs, the server must close the channel after this happens,
    // but OpenSSH doesn't do that, so we need to initiate the closing procedure ourselves.
    closeChannel();
}

void SftpChannelPrivate::handleExitSignal(const SshChannelExitSignal &signal)
{
    emit channelError(tr("The SFTP server crashed: %1.").arg(signal.error));
    closeChannel(); // See above.
}

void SftpChannelPrivate::handleCurrentPacket()
{
    qCDebug(sshLog, "Handling SFTP packet of type %d", m_incomingPacket.type());
    switch (m_incomingPacket.type()) {
    case SSH_FXP_VERSION:
        handleServerVersion();
        break;
    case SSH_FXP_HANDLE:
        handleHandle();
        break;
    case SSH_FXP_NAME:
        handleName();
        break;
    case SSH_FXP_STATUS:
        handleStatus();
        break;
    case SSH_FXP_DATA:
        handleReadData();
        break;
    case SSH_FXP_ATTRS:
        handleAttrs();
        break;
    default:
        throw SshServerException(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected packet.",
            tr("Unexpected packet of type %1.").arg(m_incomingPacket.type()));
    }
}

void SftpChannelPrivate::handleServerVersion()
{
    checkChannelActive();
    if (m_sftpState != InitSent) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_VERSION packet.");
    }

    qCDebug(sshLog, "sftp init received");
    const quint32 serverVersion = m_incomingPacket.extractServerVersion();
    if (serverVersion != ProtocolVersion) {
        emit channelError(tr("Protocol version mismatch: Expected %1, got %2")
            .arg(serverVersion).arg(ProtocolVersion));
        closeChannel();
    } else {
        m_sftpState = Initialized;
        emit initialized();
    }
}

void SftpChannelPrivate::handleHandle()
{
    const SftpHandleResponse &response = m_incomingPacket.asHandleResponse();
    JobMap::Iterator it = lookupJob(response.requestId);
    const QSharedPointer<AbstractSftpOperationWithHandle> job
        = it.value().dynamicCast<AbstractSftpOperationWithHandle>();
    if (job.isNull()) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_HANDLE packet.");
    }
    if (job->state != AbstractSftpOperationWithHandle::OpenRequested) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_HANDLE packet.");
    }
    job->remoteHandle = response.handle;
    job->state = AbstractSftpOperationWithHandle::Open;

    switch (it.value()->type()) {
    case AbstractSftpOperation::ListDir:
        handleLsHandle(it);
        break;
    case AbstractSftpOperation::CreateFile:
        handleCreateFileHandle(it);
        break;
    case AbstractSftpOperation::Download:
        handleGetHandle(it);
        break;
    case AbstractSftpOperation::UploadFile:
        handlePutHandle(it);
        break;
    default:
        Q_ASSERT(!"Oh no, I forgot to handle an SFTP operation type!");
    }
}

void SftpChannelPrivate::handleLsHandle(JobMap::Iterator it)
{
    SftpListDir::Ptr op = it.value().staticCast<SftpListDir>();
    sendData(m_outgoingPacket.generateReadDir(op->remoteHandle,
        op->jobId).rawData());
}

void SftpChannelPrivate::handleCreateFileHandle(JobMap::Iterator it)
{
    SftpCreateFile::Ptr op = it.value().staticCast<SftpCreateFile>();
    sendData(m_outgoingPacket.generateCloseHandle(op->remoteHandle,
        op->jobId).rawData());
}

void SftpChannelPrivate::handleGetHandle(JobMap::Iterator it)
{
    SftpDownload::Ptr op = it.value().staticCast<SftpDownload>();
    sendData(m_outgoingPacket.generateFstat(op->remoteHandle,
        op->jobId).rawData());
    op->statRequested = true;
}

void SftpChannelPrivate::handlePutHandle(JobMap::Iterator it)
{
    SftpUploadFile::Ptr op = it.value().staticCast<SftpUploadFile>();
    if (op->parentJob && op->parentJob->hasError)
        sendTransferCloseHandle(op, it.key());

    // OpenSSH does not implement the RFC's append functionality, so we
    // have to emulate it.
    if (op->mode == SftpAppendToExisting) {
        sendData(m_outgoingPacket.generateFstat(op->remoteHandle,
            op->jobId).rawData());
        op->statRequested = true;
    } else {
        spawnWriteRequests(it);
    }
}

void SftpChannelPrivate::handleStatus()
{
    const SftpStatusResponse &response = m_incomingPacket.asStatusResponse();
    qCDebug(sshLog, "%s: status = %d", Q_FUNC_INFO, response.status);
    JobMap::Iterator it = lookupJob(response.requestId);
    switch (it.value()->type()) {
    case AbstractSftpOperation::ListDir:
        handleLsStatus(it, response);
        break;
    case AbstractSftpOperation::Download:
        handleGetStatus(it, response);
        break;
    case AbstractSftpOperation::UploadFile:
        handlePutStatus(it, response);
        break;
    case AbstractSftpOperation::MakeDir:
        handleMkdirStatus(it, response);
        break;
    case AbstractSftpOperation::StatFile:
    case AbstractSftpOperation::RmDir:
    case AbstractSftpOperation::Rm:
    case AbstractSftpOperation::Rename:
    case AbstractSftpOperation::CreateFile:
    case AbstractSftpOperation::CreateLink:
        handleStatusGeneric(it, response);
        break;
    }
}

void SftpChannelPrivate::handleStatusGeneric(JobMap::Iterator it,
    const SftpStatusResponse &response)
{
    AbstractSftpOperation::Ptr op = it.value();
    const QString error = errorMessage(response, tr("Unknown error."));
    emit finished(op->jobId, sftpStatusToError(response.status), error);
    m_jobs.erase(it);
}

void SftpChannelPrivate::handleMkdirStatus(JobMap::Iterator it,
    const SftpStatusResponse &response)
{
    SftpMakeDir::Ptr op = it.value().staticCast<SftpMakeDir>();
    QSharedPointer<SftpUploadDir> parentJob = op->parentJob;
    if (parentJob == SftpUploadDir::Ptr()) {
        handleStatusGeneric(it, response);
        return;
    }
    if (parentJob->hasError) {
        m_jobs.erase(it);
        return;
    }

    typedef QMap<SftpMakeDir::Ptr, SftpUploadDir::Dir>::Iterator DirIt;
    DirIt dirIt = parentJob->mkdirsInProgress.find(op);
    Q_ASSERT(dirIt != parentJob->mkdirsInProgress.end());
    const QString &remoteDir = dirIt.value().remoteDir;
    if (response.status == SSH_FX_OK) {
        emit dataAvailable(parentJob->jobId,
            tr("Created remote directory \"%1\".").arg(remoteDir));
    } else if (response.status == SSH_FX_FAILURE) {
        emit dataAvailable(parentJob->jobId,
            tr("Remote directory \"%1\" already exists.").arg(remoteDir));
    } else {
        parentJob->setError();
        emit finished(parentJob->jobId,
            sftpStatusToError(response.status),
            tr("Error creating directory \"%1\": %2")
            .arg(remoteDir, response.errorString));
        m_jobs.erase(it);
        return;
    }

    QDir localDir(dirIt.value().localDir);
    const QFileInfoList &dirInfos
        = localDir.entryInfoList(QDir::Dirs | QDir::NoDotAndDotDot);
    for (const QFileInfo &dirInfo : dirInfos) {
        const QString remoteSubDir = remoteDir + u'/' + dirInfo.fileName();
        const SftpMakeDir::Ptr mkdirOp(
            new SftpMakeDir(++m_nextJobId, remoteSubDir, parentJob));
        parentJob->mkdirsInProgress.insert(mkdirOp,
            SftpUploadDir::Dir(dirInfo.absoluteFilePath(), remoteSubDir));
        createJob(mkdirOp);
    }

    const QFileInfoList &fileInfos = localDir.entryInfoList(QDir::Files);
    for (const QFileInfo &fileInfo : fileInfos) {
        QSharedPointer<QFile> localFile(new QFile(fileInfo.absoluteFilePath()));
        if (!localFile->open(QIODevice::ReadOnly)) {
            parentJob->setError();
            emit finished(parentJob->jobId,
                sftpStatusToError(response.status),
                tr("Could not open local file \"%1\": %2")
                .arg(fileInfo.absoluteFilePath(), localFile->errorString()));
            m_jobs.erase(it);
            return;
        }

        const QString remoteFilePath = remoteDir + u'/' + fileInfo.fileName();
        SftpUploadFile::Ptr uploadFileOp(new SftpUploadFile(++m_nextJobId,
            remoteFilePath, localFile, SftpOverwriteExisting, parentJob));
        createJob(uploadFileOp);
        parentJob->uploadsInProgress.append(uploadFileOp);
    }

    parentJob->mkdirsInProgress.erase(dirIt);
    if (parentJob->mkdirsInProgress.isEmpty()
        && parentJob->uploadsInProgress.isEmpty())
        emit finished(parentJob->jobId);
    m_jobs.erase(it);
}

void SftpChannelPrivate::handleLsStatus(JobMap::Iterator it,
    const SftpStatusResponse &response)
{
    SftpListDir::Ptr op = it.value().staticCast<SftpListDir>();

    if (op->parentJob && op->parentJob->hasError) {
        m_jobs.erase(it);
        return;
    }

    switch (op->state) {
    case SftpListDir::OpenRequested:
        reportRequestError(op, sftpStatusToError(response.status), errorMessage(response.errorString,
            tr("Remote directory could not be opened for reading.")));
        m_jobs.erase(it);
        break;
    case SftpListDir::Open:
        if (response.status != SSH_FX_EOF)
            reportRequestError(op,
                sftpStatusToError(response.status),
                errorMessage(response.errorString,
                tr("Failed to list remote directory contents.")));
        op->state = SftpListDir::CloseRequested;
        sendData(m_outgoingPacket.generateCloseHandle(op->remoteHandle,
            op->jobId).rawData());
        break;
    case SftpListDir::CloseRequested:
        if (op->hasError || (op->parentJob && op->parentJob->hasError)) {
            m_jobs.erase(it);
            return;
        }

        {
            const QString error = errorMessage(response,
                tr("Failed to close remote directory."));

            if (op->parentJob) {
                if (!error.isEmpty()) {
                    op->parentJob->setError();
                }
                if (op->parentJob->hasError) {
                    emit finished(op->parentJob->jobId, sftpStatusToError(response.status), error);
                } else {
                    op->parentJob->lsdirsInProgress.remove(op);
                    if (op->parentJob->lsdirsInProgress.isEmpty() &&
                        op->parentJob->downloadsInProgress.isEmpty()) {
                        emit finished(op->parentJob->jobId);
                    }
                }
            } else {
                emit finished(op->jobId, sftpStatusToError(response.status), error);
            }
        }
        m_jobs.erase(it);
        break;
    default:
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_STATUS packet.");
    }
}

void SftpChannelPrivate::handleGetStatus(JobMap::Iterator it,
    const SftpStatusResponse &response)
{
    SftpDownload::Ptr op = it.value().staticCast<SftpDownload>();

    if (op->parentJob && op->parentJob->hasError) {
        m_jobs.erase(it);
        return;
    }

    switch (op->state) {
    case SftpDownload::OpenRequested:
        reportRequestError(op, sftpStatusToError(response.status), errorMessage(response.errorString,
            tr("Failed to open remote file for reading.")));
        m_jobs.erase(it);
        break;
    case SftpDownload::Open:
        if (op->statRequested) {
            reportRequestError(op, sftpStatusToError(response.status), errorMessage(response.errorString,
                tr("Failed to retrieve information on the remote file ('stat' failed).")));
            sendTransferCloseHandle(op, response.requestId);
        } else {
            if ((response.status != SSH_FX_EOF || response.requestId != op->eofId)
                && !op->hasError)
                reportRequestError(op, sftpStatusToError(response.status), errorMessage(response.errorString,
                    tr("Failed to read remote file.")));
            finishTransferRequest(it);
        }
        break;
    case SftpDownload::CloseRequested:
        Q_ASSERT(op->inFlightCount == 1);
        if (!op->hasError) {
            if (response.status == SSH_FX_OK) {
                if (op->parentJob) {
                    op->parentJob->downloadsInProgress.removeOne(op);
                    if (op->parentJob->lsdirsInProgress.isEmpty()
                        && op->parentJob->downloadsInProgress.isEmpty())
                        emit finished(op->parentJob->jobId);
                } else {
                    emit finished(op->jobId);
                }
            } else {
                const QString error = errorMessage(response.errorString,
                    tr("Failed to close remote file."));
                reportRequestError(op, sftpStatusToError(response.status), error);
            }
        }
        removeTransferRequest(it);
        break;
    default:
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_STATUS packet.");
    }
}

void SftpChannelPrivate::handlePutStatus(JobMap::Iterator it,
    const SftpStatusResponse &response)
{
    SftpUploadFile::Ptr job = it.value().staticCast<SftpUploadFile>();
    switch (job->state) {
    case SftpUploadFile::OpenRequested: {
        bool emitError = false;
        if (job->parentJob) {
            if (!job->parentJob->hasError) {
                job->parentJob->setError();
                emitError = true;
            }
        } else {
            emitError = true;
        }

        if (emitError) {
            emit finished(job->jobId,
                sftpStatusToError(response.status),
                errorMessage(response.errorString,
                    tr("Failed to open remote file for writing.")));
        }
        m_jobs.erase(it);
        break;
    }
    case SftpUploadFile::Open:
        if (job->hasError || (job->parentJob && job->parentJob->hasError)) {
            job->hasError = true;
            finishTransferRequest(it);
            return;
        }

        if (response.status == SSH_FX_OK) {
            sendWriteRequest(it);
        } else {
            if (job->parentJob)
                job->parentJob->setError();
            reportRequestError(job, sftpStatusToError(response.status), errorMessage(response.errorString,
                tr("Failed to write remote file.")));
            finishTransferRequest(it);
        }
        break;
    case SftpUploadFile::CloseRequested:
        Q_ASSERT(job->inFlightCount == 1);
        if (job->hasError || (job->parentJob && job->parentJob->hasError)) {
            m_jobs.erase(it);
            return;
        }

        if (response.status == SSH_FX_OK) {
            if (job->parentJob) {
                job->parentJob->uploadsInProgress.removeOne(job);
                if (job->parentJob->mkdirsInProgress.isEmpty()
                    && job->parentJob->uploadsInProgress.isEmpty())
                    emit finished(job->parentJob->jobId);
            } else {
                emit finished(job->jobId);
            }
        } else {
            const QString error = errorMessage(response.errorString,
                tr("Failed to close remote file."));
            if (job->parentJob) {
                job->parentJob->setError();
                emit finished(job->parentJob->jobId, sftpStatusToError(response.status), error);
            } else {
                emit finished(job->jobId, sftpStatusToError(response.status), error);
            }
        }
        m_jobs.erase(it);
        break;
    default:
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_STATUS packet.");
    }
}

void SftpChannelPrivate::handleName()
{
    const SftpNameResponse &response = m_incomingPacket.asNameResponse();
    JobMap::Iterator it = lookupJob(response.requestId);
    switch (it.value()->type()) {
    case AbstractSftpOperation::ListDir: {
        SftpListDir::Ptr op = it.value().staticCast<SftpListDir>();
        if (op->state != SftpListDir::Open) {
            throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
                "Unexpected SSH_FXP_NAME packet.");
        }

        QList<SftpFileInfo> fileInfoList;
        for (int i = 0; i < response.files.count(); ++i) {
            const SftpFile &file = response.files.at(i);

            SftpFileInfo fileInfo;
            fileInfo.name = file.fileName;
            attributesToFileInfo(file.attributes, fileInfo);
            fileInfoList << fileInfo;
        }

        if (op->parentJob) {
            handleDownloadDir(op, fileInfoList);
        } else {
            emit fileInfoAvailable(op->jobId, fileInfoList);
        }

        sendData(m_outgoingPacket.generateReadDir(op->remoteHandle,
            op->jobId).rawData());
        break;
    }
    default:
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_NAME packet.");
    }
}

void SftpChannelPrivate::handleReadData()
{
    const SftpDataResponse &response = m_incomingPacket.asDataResponse();
    JobMap::Iterator it = lookupJob(response.requestId);
    if (it.value()->type() != AbstractSftpOperation::Download) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_DATA packet.");
    }

    SftpDownload::Ptr op = it.value().staticCast<SftpDownload>();
    if (op->hasError) {
        finishTransferRequest(it);
        return;
    }

    if (!op->localFile->isOpen()) {
        QFile *fileDevice = qobject_cast<QFile*>(op->localFile.data());
        if (fileDevice){
            if (!Internal::openFile(fileDevice, op->mode)) {
                reportRequestError(op, SftpError::GenericFailure, tr("Cannot open file ") + fileDevice->fileName());
                finishTransferRequest(it);
                return;
            }
        } else {
            reportRequestError(op, SftpError::GenericFailure, tr("File to upload is not open"));
            finishTransferRequest(it);
            return;
        }
    }

    if (!op->localFile->seek(op->offsets[response.requestId])) {
        reportRequestError(op, SftpError::GenericFailure, op->localFile->errorString());
        finishTransferRequest(it);
        return;
    }

    if (op->localFile->write(response.data) != response.data.size()) {
        reportRequestError(op, SftpError::GenericFailure, op->localFile->errorString());
        finishTransferRequest(it);
        return;
    }

    emit transferProgress(op->jobId, op->localFile->pos(), op->fileSize);

    if (op->offset >= op->fileSize && op->fileSize != 0)
        finishTransferRequest(it);
    else
        sendReadRequest(op, response.requestId);
}

void SftpChannelPrivate::handleAttrs()
{
    const SftpAttrsResponse &response = m_incomingPacket.asAttrsResponse();
    JobMap::Iterator it = lookupJob(response.requestId);

    SftpStatFile::Ptr statOp = it.value().dynamicCast<SftpStatFile>();
    if (statOp) {
        SftpFileInfo fileInfo;
        fileInfo.name = QFileInfo(statOp->path).fileName();
        attributesToFileInfo(response.attrs, fileInfo);
        emit fileInfoAvailable(it.key(), QList<SftpFileInfo>() << fileInfo);
        emit finished(it.key());
        m_jobs.erase(it);
        return;
    }

    AbstractSftpTransfer::Ptr transfer
        = it.value().dynamicCast<AbstractSftpTransfer>();
    if (!transfer || transfer->state != AbstractSftpTransfer::Open
        || !transfer->statRequested) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_FXP_ATTRS packet.");
    }
    Q_ASSERT(transfer->type() == AbstractSftpOperation::UploadFile
        || transfer->type() == AbstractSftpOperation::Download);

    if (transfer->type() == AbstractSftpOperation::Download) {
        SftpDownload::Ptr op = transfer.staticCast<SftpDownload>();
        if (response.attrs.sizePresent) {
            op->fileSize = response.attrs.size;
        } else {
            op->fileSize = 0;
            op->eofId = op->jobId;
        }
        op->statRequested = false;
        emit transferProgress(op->jobId, op->offset, op->fileSize);
        spawnReadRequests(op);
    } else {
        SftpUploadFile::Ptr op = transfer.staticCast<SftpUploadFile>();
        if (op->parentJob && op->parentJob->hasError) {
            op->hasError = true;
            sendTransferCloseHandle(op, op->jobId);
            return;
        }

        if (response.attrs.sizePresent) {
            op->offset = response.attrs.size;
            emit transferProgress(op->jobId, op->offset, op->fileSize);
            spawnWriteRequests(it);
        } else {
            if (op->parentJob)
                op->parentJob->setError();
            reportRequestError(op, SftpError::UnsupportedOperation, tr("Cannot append to remote file: "
                "Server does not support the file size attribute."));
            sendTransferCloseHandle(op, op->jobId);
        }
    }
}

void SftpChannelPrivate::handleDownloadDir(SftpListDir::Ptr op,
    const QList<SftpFileInfo> &fileInfoList)
{
    if (op->parentJob->hasError) {
        return;
    }

    for (SftpFileInfo fileInfo : fileInfoList) {
        Internal::SftpDownloadDir::Dir dir = op->parentJob->lsdirsInProgress[op];
        QString fullPathRemote = QDir(dir.remoteDir).path() + u'/' + fileInfo.name;
        QString fullPathLocal = QDir(dir.localDir).path() + u'/' + fileInfo.name;

        if (fileInfo.type == FileTypeRegular) {
            QSharedPointer<QFile> localFile(new QFile(fullPathLocal));
            Internal::SftpDownload::Ptr downloadJob = Internal::SftpDownload::Ptr(
                new Internal::SftpDownload(++m_nextJobId, fullPathRemote, localFile,
                                           op->parentJob->mode, op->parentJob));

            op->parentJob->downloadsInProgress.append(downloadJob);
            createJob(downloadJob);

        } else if (fileInfo.type == FileTypeDirectory) {
            if (fileInfo.name == u"." || fileInfo.name == u"..") {
                continue;
            }

            if (!QDir().mkpath(fullPathLocal)) {
                reportRequestError(op, SftpError::GenericFailure, tr("Cannot create directory ") + fullPathLocal);
                break;
            }

            Internal::SftpListDir::Ptr lsdir = Internal::SftpListDir::Ptr(
                new Internal::SftpListDir(++m_nextJobId, fullPathRemote, op->parentJob));

            op->parentJob->lsdirsInProgress.insert(lsdir,
                Internal::SftpDownloadDir::Dir(fullPathLocal, fullPathRemote));
            createJob(lsdir);

        } else {
            // andres.pagliano TODO handle?
        }
    }
}

SftpChannelPrivate::JobMap::Iterator SftpChannelPrivate::lookupJob(SftpJobId id)
{
    JobMap::Iterator it = m_jobs.find(id);
    if (it == m_jobs.end()) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Invalid request id in SFTP packet.");
    }
    return it;
}

void SftpChannelPrivate::closeHook()
{
    for (JobMap::ConstIterator it = m_jobs.constBegin(); it != m_jobs.constEnd(); ++it)
        emit finished(it.key(), SftpError::EndOfFile, tr("SFTP channel closed unexpectedly."));
    m_jobs.clear();
    m_incomingData.clear();
    m_incomingPacket.clear();
    emit closed();
}

void SftpChannelPrivate::handleOpenSuccessInternal()
{
    qCDebug(sshLog, "SFTP session started");
    m_sendFacility.sendSftpPacket(remoteChannel());
    m_sftpState = SubsystemRequested;
}

void SftpChannelPrivate::handleOpenFailureInternal(const QString &reason)
{
    if (channelState() != SessionRequested) {
        throw SSH_SERVER_EXCEPTION(SSH_DISCONNECT_PROTOCOL_ERROR,
            "Unexpected SSH_MSG_CHANNEL_OPEN_FAILURE packet.");
    }
    emit channelError(tr("Server could not start session: %1").arg(reason));
}

void SftpChannelPrivate::sendReadRequest(const SftpDownload::Ptr &job,
    quint32 requestId)
{
    Q_ASSERT(job->eofId == SftpInvalidJob);
    sendData(m_outgoingPacket.generateReadFile(job->remoteHandle, job->offset,
        AbstractSftpPacket::MaxDataSize, requestId).rawData());
    job->offsets[requestId] = job->offset;
    job->offset += AbstractSftpPacket::MaxDataSize;
    if (job->offset >= job->fileSize)
        job->eofId = requestId;
}

void SftpChannelPrivate::reportRequestError(const AbstractSftpOperationWithHandle::Ptr &job,
    const SftpError errorType,
    const QString &error)
{
    // andres.pagliano TODO refactor

    // Report list error during download dir
    SftpListDir::Ptr lsjob = job.dynamicCast<SftpListDir>();
    if (!lsjob.isNull() && lsjob->parentJob) {
        if (!lsjob->parentJob->hasError) {
            emit finished(lsjob->parentJob->jobId, errorType, error);
            lsjob->parentJob->hasError = true;
        }
    } else {
        // Report download error during recursive download dir
        SftpDownload::Ptr djob = job.dynamicCast<SftpDownload>();
        if (!djob.isNull() && djob->parentJob) {
            if (!djob->parentJob->hasError) {
                emit finished(djob->parentJob->jobId, errorType, error);
                djob->parentJob->hasError = true;
            }
        } else {
            // Other error
            emit finished(job->jobId, errorType, error);
        }
    }
    job->hasError = true;
}

void SftpChannelPrivate::finishTransferRequest(JobMap::Iterator it)
{
    AbstractSftpTransfer::Ptr job = it.value().staticCast<AbstractSftpTransfer>();
    if (job->inFlightCount == 1)
        sendTransferCloseHandle(job, it.key());
    else
        removeTransferRequest(it);
}

void SftpChannelPrivate::sendTransferCloseHandle(const AbstractSftpTransfer::Ptr &job,
    quint32 requestId)
{
    sendData(m_outgoingPacket.generateCloseHandle(job->remoteHandle,
       requestId).rawData());
    job->state = SftpDownload::CloseRequested;
}

void SftpChannelPrivate::attributesToFileInfo(const SftpFileAttributes &attributes,
    SftpFileInfo &fileInfo) const
{
    if (attributes.sizePresent) {
        fileInfo.sizeValid = true;
        fileInfo.size = attributes.size;
    }
    if (attributes.permissionsPresent) {
        if (attributes.permissions & 0x8000) // S_IFREG
            fileInfo.type = FileTypeRegular;
        else if (attributes.permissions & 0x4000) // S_IFDIR
            fileInfo.type = FileTypeDirectory;
        else
            fileInfo.type = FileTypeOther;
        fileInfo.permissionsValid = true;
        fileInfo.permissions = {};

        if (attributes.timesPresent) {
            fileInfo.atime = attributes.atime;
            fileInfo.mtime = attributes.mtime;
            fileInfo.timestampsValid = true;
        }

        if (attributes.permissions & 00001) // S_IXOTH
            fileInfo.permissions |= QFile::ExeOther;
        if (attributes.permissions & 00002) // S_IWOTH
            fileInfo.permissions |= QFile::WriteOther;
        if (attributes.permissions & 00004) // S_IROTH
            fileInfo.permissions |= QFile::ReadOther;
        if (attributes.permissions & 00010) // S_IXGRP
            fileInfo.permissions |= QFile::ExeGroup;
        if (attributes.permissions & 00020) // S_IWGRP
            fileInfo.permissions |= QFile::WriteGroup;
        if (attributes.permissions & 00040) // S_IRGRP
            fileInfo.permissions |= QFile::ReadGroup;
        if (attributes.permissions & 00100) // S_IXUSR
            fileInfo.permissions |= QFile::ExeUser | QFile::ExeOwner;
        if (attributes.permissions & 00200) // S_IWUSR
            fileInfo.permissions |= QFile::WriteUser | QFile::WriteOwner;
        if (attributes.permissions & 00400) // S_IRUSR
            fileInfo.permissions |= QFile::ReadUser | QFile::ReadOwner;
    }
}

void SftpChannelPrivate::removeTransferRequest(JobMap::Iterator it)
{
    --it.value().staticCast<AbstractSftpTransfer>()->inFlightCount;
    m_jobs.erase(it);
}

void SftpChannelPrivate::sendWriteRequest(JobMap::Iterator it)
{
    SftpUploadFile::Ptr job = it.value().staticCast<SftpUploadFile>();

    emit transferProgress(job->jobId, job->localFile->pos(), job->localFile->size());

    QByteArray data = job->localFile->read(AbstractSftpPacket::MaxDataSize);

    QFileDevice *fileDevice = qobject_cast<QFileDevice*>(job->localFile.data());
    if (fileDevice && fileDevice->error() != QFileDevice::NoError) {
        if (job->parentJob)
            job->parentJob->setError();
        reportRequestError(job, SftpError::GenericFailure, tr("Error reading local file: %1")
            .arg(job->localFile->errorString()));
        finishTransferRequest(it);
    } else if (data.isEmpty()) {
        finishTransferRequest(it);
    } else {
        sendData(m_outgoingPacket.generateWriteFile(job->remoteHandle,
            job->offset, data, it.key()).rawData());
        job->offset += AbstractSftpPacket::MaxDataSize;
    }
}

void SftpChannelPrivate::spawnWriteRequests(JobMap::Iterator it)
{
    SftpUploadFile::Ptr op = it.value().staticCast<SftpUploadFile>();
    op->calculateInFlightCount(AbstractSftpPacket::MaxDataSize);
    sendWriteRequest(it);
    for (int i = 1; !op->hasError && i < op->inFlightCount; ++i)
        sendWriteRequest(m_jobs.insert(++m_nextJobId, op));
}

void SftpChannelPrivate::spawnReadRequests(const SftpDownload::Ptr &job)
{
    job->calculateInFlightCount(AbstractSftpPacket::MaxDataSize);
    sendReadRequest(job, job->jobId);
    for (int i = 1; i < job->inFlightCount; ++i) {
        const quint32 requestId = ++m_nextJobId;
        m_jobs.insert(requestId, job);
        sendReadRequest(job, requestId);
    }
}

} // namespace Internal
} // namespace QSsh