/* === This file is part of Calamares - <https://github.com/calamares> ===
 *
 *   Copyright 2014, Aurélien Gâteau <agateau@kde.org>
 *   Copyright 2015-2016, Teo Mrnjavac <teo@kde.org>
 *   Copyright 2018-2019, Adriaan de Groot <groot@kde.org>
 *   Copyright 2018, Andrius Štikonas <andrius@stikonas.eu>
 *   Copyright 2018, Caio Jordão Carvalho <caiojcarvalho@gmail.com>
 *   Copyright 2019, Collabora Ltd
 *
 *   Calamares is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   Calamares is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with Calamares. If not, see <http://www.gnu.org/licenses/>.
 */

#include "PartitionPage.h"

// Local
#include "core/BootLoaderModel.h"
#include "core/DeviceModel.h"
#include "core/PartitionCoreModule.h"
#include "core/PartitionInfo.h"
#include "core/PartitionModel.h"
#include "core/PartUtils.h"
#include "core/KPMHelpers.h"
#include "gui/CreatePartitionDialog.h"
#include "gui/CreateVolumeGroupDialog.h"
#include "gui/EditExistingPartitionDialog.h"
#include "gui/ResizeVolumeGroupDialog.h"
#include "gui/ScanningDialog.h"

#include "ui_PartitionPage.h"
#include "ui_CreatePartitionTableDialog.h"

#include "utils/Logger.h"
#include "utils/Retranslator.h"
#include "Branding.h"
#include "JobQueue.h"
#include "GlobalStorage.h"

// KPMcore
#include <kpmcore/core/device.h>
#include <kpmcore/core/partition.h>
#ifdef WITH_KPMCORE4API
#include <kpmcore/core/softwareraid.h>
#endif
#include <kpmcore/ops/deactivatevolumegroupoperation.h>
#include <kpmcore/ops/removevolumegroupoperation.h>

// Qt
#include <QHeaderView>
#include <QItemSelectionModel>
#include <QMessageBox>
#include <QPointer>
#include <QDir>
#include <QFutureWatcher>
#include <QtConcurrent/QtConcurrent>

PartitionPage::PartitionPage( PartitionCoreModule* core, QWidget* parent )
    : QWidget( parent )
    , m_ui( new Ui_PartitionPage )
    , m_core( core )
    , m_lastSelectedBootLoaderIndex(-1)
    , m_isEfi( false )
{
    m_isEfi = PartUtils::isEfiSystem();

    m_ui->setupUi( this );
    m_ui->partitionLabelsView->setVisible(
            Calamares::JobQueue::instance()->globalStorage()->
                    value( "alwaysShowPartitionLabels" ).toBool() );
    m_ui->deviceComboBox->setModel( m_core->deviceModel() );
    m_ui->bootLoaderComboBox->setModel( m_core->bootLoaderModel() );
    connect( m_core->bootLoaderModel(), &QAbstractItemModel::modelReset, this, &PartitionPage::restoreSelectedBootLoader );
    PartitionBarsView::NestedPartitionsMode mode = Calamares::JobQueue::instance()->globalStorage()->
                                                   value( "drawNestedPartitions" ).toBool() ?
                                                       PartitionBarsView::DrawNestedPartitions :
                                                       PartitionBarsView::NoNestedPartitions;
    m_ui->partitionBarsView->setNestedPartitionsMode( mode );
    updateButtons();
    updateBootLoaderInstallPath();

    updateFromCurrentDevice();

    connect( m_ui->deviceComboBox, &QComboBox::currentTextChanged, this, &PartitionPage::updateFromCurrentDevice );
    connect( m_ui->bootLoaderComboBox, QOverload<int>::of(&QComboBox::activated), this, &PartitionPage::updateSelectedBootLoaderIndex );
    connect( m_ui->bootLoaderComboBox, &QComboBox::currentTextChanged, this, &PartitionPage::updateBootLoaderInstallPath );

    connect( m_core, &PartitionCoreModule::isDirtyChanged, m_ui->revertButton, &QWidget::setEnabled );

    connect( m_ui->partitionTreeView, &QAbstractItemView::doubleClicked, this, &PartitionPage::onPartitionViewActivated );
    connect( m_ui->revertButton, &QAbstractButton::clicked, this, &PartitionPage::onRevertClicked );
    connect( m_ui->newVolumeGroupButton, &QAbstractButton::clicked, this, &PartitionPage::onNewVolumeGroupClicked );
    connect( m_ui->resizeVolumeGroupButton, &QAbstractButton::clicked, this, &PartitionPage::onResizeVolumeGroupClicked );
    connect( m_ui->deactivateVolumeGroupButton, &QAbstractButton::clicked, this, &PartitionPage::onDeactivateVolumeGroupClicked );
    connect( m_ui->removeVolumeGroupButton, &QAbstractButton::clicked, this, &PartitionPage::onRemoveVolumeGroupClicked );
    connect( m_ui->newPartitionTableButton, &QAbstractButton::clicked, this, &PartitionPage::onNewPartitionTableClicked );
    connect( m_ui->createButton, &QAbstractButton::clicked, this, &PartitionPage::onCreateClicked );
    connect( m_ui->editButton, &QAbstractButton::clicked, this, &PartitionPage::onEditClicked );
    connect( m_ui->deleteButton, &QAbstractButton::clicked, this, &PartitionPage::onDeleteClicked );

    if ( m_isEfi ) {
        m_ui->bootLoaderComboBox->hide();
        m_ui->label_3->hide();
    }

    CALAMARES_RETRANSLATE( m_ui->retranslateUi( this ); )
}

PartitionPage::~PartitionPage()
{
}

void
PartitionPage::updateButtons()
{
    bool create = false, createTable = false, edit = false, del = false, currentDeviceIsVG = false, isDeactivable = false;
    bool isRemovable = false, isVGdeactivated = false;

    QModelIndex index = m_ui->partitionTreeView->currentIndex();
    if ( index.isValid() )
    {
        const PartitionModel* model = static_cast< const PartitionModel* >( index.model() );
        Q_ASSERT( model );
        Partition* partition = model->partitionForIndex( index );
        Q_ASSERT( partition );
        bool isFree = KPMHelpers::isPartitionFreeSpace( partition );
        bool isExtended = partition->roles().has( PartitionRole::Extended );

        bool isInVG = m_core->isInVG( partition );

        create = isFree;

        // Keep it simple for now: do not support editing extended partitions as
        // it does not work with our current edit implementation which is
        // actually remove + add. This would not work with extended partitions
        // because they need to be created *before* creating logical partitions
        // inside them, so an edit must be applied without altering the job
        // order.
        // TODO: See if LVM PVs can be edited in Calamares
        edit = !isFree && !isExtended;
        del = !isFree && !isInVG;
    }

    if ( m_ui->deviceComboBox->currentIndex() >= 0 )
    {
        Device* device = nullptr;
        QModelIndex deviceIndex = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
        if ( deviceIndex.isValid() )
            device = m_core->deviceModel()->deviceForIndex( deviceIndex );
        if ( !device )
            cWarning() << "Device for updateButtons is nullptr";
        else if ( device->type() != Device::Type::LVM_Device )
        {
            createTable = true;

#ifdef WITH_KPMCORE4API
            if ( device->type() == Device::Type::SoftwareRAID_Device &&
                 static_cast< SoftwareRAID* >(device)->status() == SoftwareRAID::Status::Inactive )
            {
                createTable = false;
                create = false;
            }
#endif
        }
        else
        {
            currentDeviceIsVG = true;

            LvmDevice* lvmDevice = dynamic_cast<LvmDevice*>(m_core->deviceModel()->deviceForIndex( deviceIndex ));

            isDeactivable = DeactivateVolumeGroupOperation::isDeactivatable( lvmDevice );
            isRemovable = RemoveVolumeGroupOperation::isRemovable( lvmDevice );

            isVGdeactivated = m_core->isVGdeactivated( lvmDevice );

            if ( isVGdeactivated )
                m_ui->revertButton->setEnabled( true );
        }
    }

    m_ui->createButton->setEnabled( create );
    m_ui->editButton->setEnabled( edit );
    m_ui->deleteButton->setEnabled( del );
    m_ui->newPartitionTableButton->setEnabled( createTable );
    m_ui->resizeVolumeGroupButton->setEnabled( currentDeviceIsVG && !isVGdeactivated );
    m_ui->deactivateVolumeGroupButton->setEnabled( currentDeviceIsVG && isDeactivable && !isVGdeactivated );
    m_ui->removeVolumeGroupButton->setEnabled( currentDeviceIsVG && isRemovable );
}

void
PartitionPage::onNewPartitionTableClicked()
{
    QModelIndex index = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
    Q_ASSERT( index.isValid() );
    Device* device = m_core->deviceModel()->deviceForIndex( index );

    QPointer<QDialog> dlg = new QDialog( this );
    Ui_CreatePartitionTableDialog ui;
    ui.setupUi( dlg.data() );
    QString areYouSure = tr( "Are you sure you want to create a new partition table on %1?" ).arg( device->name() );
    if ( PartUtils::isEfiSystem() )
        ui.gptRadioButton->setChecked( true );
    else
        ui.mbrRadioButton->setChecked( true );

    ui.areYouSureLabel->setText( areYouSure );
    if ( dlg->exec() == QDialog::Accepted )
    {
        PartitionTable::TableType type = ui.mbrRadioButton->isChecked() ? PartitionTable::msdos : PartitionTable::gpt;
        m_core->createPartitionTable( device, type );
    }
    delete dlg;
    // PartionModelReset isn't emitted after createPartitionTable, so we have to manually update
    // the bootLoader index after the reset.
    updateBootLoaderIndex();
}

bool
PartitionPage::checkCanCreate( Device* device )
{
    auto table = device->partitionTable();

    if ( table->type() == PartitionTable::msdos ||table->type() == PartitionTable::msdos_sectorbased )
    {
        cDebug() << "Checking MSDOS partition" << table->numPrimaries() << "primaries, max" << table->maxPrimaries();

        if ( ( table->numPrimaries() >= table->maxPrimaries() ) && !table->hasExtended() )
        {
            QMessageBox::warning( this, tr( "Can not create new partition" ),
                tr( "The partition table on %1 already has %2 primary partitions, and no more can be added. "
                    "Please remove one primary partition and add an extended partition, instead." ).arg( device->name() ).arg( table->numPrimaries() )
            );
            return false;
        }
        return true;
    }
    else
        return true;  // GPT is fine
}

void
PartitionPage::onNewVolumeGroupClicked()
{
    QString vgName;
    QVector< const Partition* > selectedPVs;
    qint64 peSize = 4;

    QVector< const Partition* > availablePVs;

    for ( const Partition* p : m_core->lvmPVs() )
        if ( !m_core->isInVG( p ) )
            availablePVs << p;

    QPointer< CreateVolumeGroupDialog > dlg = new CreateVolumeGroupDialog( vgName,
                                                                           selectedPVs,
                                                                           availablePVs,
                                                                           peSize,
                                                                           this );

    if ( dlg->exec() == QDialog::Accepted )
    {
        QModelIndex partitionIndex = m_ui->partitionTreeView->currentIndex();

        if ( partitionIndex.isValid() )
        {
            const PartitionModel* model = static_cast< const PartitionModel* >( partitionIndex.model() );
            Q_ASSERT( model );
            Partition* partition = model->partitionForIndex( partitionIndex );
            Q_ASSERT( partition );

            // Disable delete button if current partition was selected to be in VG
            // TODO: Should Calamares edit LVM PVs which are in VGs?
            if ( selectedPVs.contains( partition ) )
                m_ui->deleteButton->setEnabled( false );
        }

        QModelIndex deviceIndex = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
        Q_ASSERT( deviceIndex.isValid() );

        QVariant previousIndexDeviceData = m_core->deviceModel()->data( deviceIndex, Qt::ToolTipRole );

        // Creating new VG
        m_core->createVolumeGroup( vgName, selectedPVs, peSize );

        // As createVolumeGroup method call resets deviceModel,
        // is needed to set the current index in deviceComboBox as the previous one
        int previousIndex = m_ui->deviceComboBox->findData( previousIndexDeviceData, Qt::ToolTipRole );

        m_ui->deviceComboBox->setCurrentIndex( ( previousIndex < 0  ) ? 0 : previousIndex );
        updateFromCurrentDevice();
    }

    delete dlg;
}

void
PartitionPage::onResizeVolumeGroupClicked()
{
    QModelIndex deviceIndex = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
    LvmDevice* device = dynamic_cast< LvmDevice* >( m_core->deviceModel()->deviceForIndex( deviceIndex ) );

    Q_ASSERT( device && device->type() == Device::Type::LVM_Device );

    QVector< const Partition* > availablePVs;
    QVector< const Partition* > selectedPVs;

    for ( const Partition* p : m_core->lvmPVs() )
        if ( !m_core->isInVG( p ) )
            availablePVs << p;

    QPointer< ResizeVolumeGroupDialog > dlg = new ResizeVolumeGroupDialog( device,
                                                                           availablePVs,
                                                                           selectedPVs,
                                                                           this );

    if ( dlg->exec() == QDialog::Accepted )
        m_core->resizeVolumeGroup( device, selectedPVs );

    delete dlg;
}

void
PartitionPage::onDeactivateVolumeGroupClicked()
{
    QModelIndex deviceIndex = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
    LvmDevice* device = dynamic_cast< LvmDevice* >( m_core->deviceModel()->deviceForIndex( deviceIndex ) );

    Q_ASSERT( device && device->type() == Device::Type::LVM_Device );

    m_core->deactivateVolumeGroup( device );

    updateFromCurrentDevice();

    PartitionModel* model = m_core->partitionModelForDevice( device );
    model->update();
}

void
PartitionPage::onRemoveVolumeGroupClicked()
{
    QModelIndex deviceIndex = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
    LvmDevice* device = dynamic_cast< LvmDevice* >( m_core->deviceModel()->deviceForIndex( deviceIndex ) );

    Q_ASSERT( device && device->type() == Device::Type::LVM_Device );

    m_core->removeVolumeGroup( device );
}

void
PartitionPage::onCreateClicked()
{
    QModelIndex index = m_ui->partitionTreeView->currentIndex();
    Q_ASSERT( index.isValid() );

    const PartitionModel* model = static_cast< const PartitionModel* >( index.model() );
    Partition* partition = model->partitionForIndex( index );
    Q_ASSERT( partition );

    if ( !checkCanCreate( model->device() ) )
        return;

    CreatePartitionDialog dlg(
        model->device(),
        partition->parent(),
        nullptr,
        getCurrentUsedMountpoints(),
        this );
    dlg.initFromFreeSpace( partition );
    if ( dlg.exec() == QDialog::Accepted )
    {
        Partition* newPart = dlg.createPartition();
        m_core->createPartition( model->device(), newPart, dlg.newFlags() );
    }
}

void
PartitionPage::onEditClicked()
{
    QModelIndex index = m_ui->partitionTreeView->currentIndex();
    Q_ASSERT( index.isValid() );

    const PartitionModel* model = static_cast< const PartitionModel* >( index.model() );
    Partition* partition = model->partitionForIndex( index );
    Q_ASSERT( partition );

    if ( KPMHelpers::isPartitionNew( partition ) )
        updatePartitionToCreate( model->device(), partition );
    else
        editExistingPartition( model->device(), partition );

}

void
PartitionPage::onDeleteClicked()
{
    QModelIndex index = m_ui->partitionTreeView->currentIndex();
    Q_ASSERT( index.isValid() );

    const PartitionModel* model = static_cast< const PartitionModel* >( index.model() );
    Partition* partition = model->partitionForIndex( index );
    Q_ASSERT( partition );

    m_core->deletePartition( model->device(), partition );
}


void
PartitionPage::onRevertClicked()
{
    ScanningDialog::run(
        QtConcurrent::run( [ this ]
        {
            QMutexLocker locker( &m_revertMutex );

            int oldIndex = m_ui->deviceComboBox->currentIndex();
            m_core->revertAllDevices();
            m_ui->deviceComboBox->setCurrentIndex( ( oldIndex < 0 )  ? 0 : oldIndex );
            updateFromCurrentDevice();
        } ),
        [ this ]{
            m_lastSelectedBootLoaderIndex = -1;
            if( m_ui->bootLoaderComboBox->currentIndex() < 0 ) {
                m_ui->bootLoaderComboBox->setCurrentIndex( 0 );
            }
        },
        this );
}

void
PartitionPage::onPartitionViewActivated()
{
    QModelIndex index = m_ui->partitionTreeView->currentIndex();
    if ( !index.isValid() )
        return;

    const PartitionModel* model = static_cast< const PartitionModel* >( index.model() );
    Q_ASSERT( model );
    Partition* partition = model->partitionForIndex( index );
    Q_ASSERT( partition );

    // Use the buttons to trigger the actions so that they do nothing if they
    // are disabled. Alternatively, the code could use QAction to centralize,
    // but I don't expect there will be other occurences of triggering the same
    // action from multiple UI elements in this page, so it does not feel worth
    // the price.
    if ( KPMHelpers::isPartitionFreeSpace( partition ) )
        m_ui->createButton->click();
    else
        m_ui->editButton->click();
}

void
PartitionPage::updatePartitionToCreate( Device* device, Partition* partition )
{
    QStringList mountPoints = getCurrentUsedMountpoints();
    mountPoints.removeOne( PartitionInfo::mountPoint( partition ) );

    QPointer< CreatePartitionDialog > dlg = new CreatePartitionDialog( device,
                                                                       partition->parent(),
                                                                       partition,
                                                                       mountPoints,
                                                                       this );
    dlg->initFromPartitionToCreate( partition );
    if ( dlg->exec() == QDialog::Accepted )
    {
        Partition* newPartition = dlg->createPartition();
        m_core->deletePartition( device, partition );
        m_core->createPartition( device, newPartition, dlg->newFlags() );
    }
    delete dlg;
}

void
PartitionPage::editExistingPartition( Device* device, Partition* partition )
{
    QStringList mountPoints = getCurrentUsedMountpoints();
    mountPoints.removeOne( PartitionInfo::mountPoint( partition ) );

    QPointer<EditExistingPartitionDialog> dlg = new EditExistingPartitionDialog( device, partition, mountPoints, this );
    if ( dlg->exec() == QDialog::Accepted )
        dlg->applyChanges( m_core );
    delete dlg;
}

void
PartitionPage::updateBootLoaderInstallPath()
{
    if ( m_isEfi || !m_ui->bootLoaderComboBox->isVisible() )
        return;

    QVariant var = m_ui->bootLoaderComboBox->currentData( BootLoaderModel::BootLoaderPathRole );
    if ( !var.isValid() )
        return;
    cDebug() << "PartitionPage::updateBootLoaderInstallPath" << var.toString();
    m_core->setBootLoaderInstallPath( var.toString() );
}

void
PartitionPage::updateSelectedBootLoaderIndex()
{
    m_lastSelectedBootLoaderIndex = m_ui->bootLoaderComboBox->currentIndex();
    cDebug() << "Selected bootloader index" << m_lastSelectedBootLoaderIndex;
}

void
PartitionPage::restoreSelectedBootLoader()
{
    Calamares::restoreSelectedBootLoader( *(m_ui->bootLoaderComboBox), m_core->bootLoaderInstallPath() );
}


void
PartitionPage::updateFromCurrentDevice()
{
    QModelIndex index = m_core->deviceModel()->index( m_ui->deviceComboBox->currentIndex(), 0 );
    if ( !index.isValid() )
        return;

    Device* device = m_core->deviceModel()->deviceForIndex( index );

    QAbstractItemModel* oldModel = m_ui->partitionTreeView->model();
    if ( oldModel )
        disconnect( oldModel, nullptr, this, nullptr );

    PartitionModel* model = m_core->partitionModelForDevice( device );
    m_ui->partitionBarsView->setModel( model );
    m_ui->partitionLabelsView->setModel( model );
    m_ui->partitionTreeView->setModel( model );
    m_ui->partitionTreeView->expandAll();

    // Make all views use the same selection model.
    if ( m_ui->partitionBarsView->selectionModel() !=
         m_ui->partitionTreeView->selectionModel() ||
         m_ui->partitionBarsView->selectionModel() !=
         m_ui->partitionLabelsView->selectionModel() )
    {
        // Tree view
        QItemSelectionModel* selectionModel = m_ui->partitionTreeView->selectionModel();
        m_ui->partitionTreeView->setSelectionModel( m_ui->partitionBarsView->selectionModel() );
        selectionModel->deleteLater();

        // Labels view
        selectionModel = m_ui->partitionLabelsView->selectionModel();
        m_ui->partitionLabelsView->setSelectionModel( m_ui->partitionBarsView->selectionModel() );
        selectionModel->deleteLater();
    }

    // This is necessary because even with the same selection model it might happen that
    // a !=0 column is selected in the tree view, which for some reason doesn't trigger a
    // timely repaint in the bars view.
    connect( m_ui->partitionBarsView->selectionModel(), &QItemSelectionModel::currentChanged,
             this, [=]
    {
        QModelIndex selectedIndex = m_ui->partitionBarsView->selectionModel()->currentIndex();
        selectedIndex = selectedIndex.sibling( selectedIndex.row(), 0 );
        m_ui->partitionBarsView->setCurrentIndex( selectedIndex );
        m_ui->partitionLabelsView->setCurrentIndex( selectedIndex );
    }, Qt::UniqueConnection );

    // Must be done here because we need to have a model set to define
    // individual column resize mode
    QHeaderView* header = m_ui->partitionTreeView->header();
    header->setSectionResizeMode( QHeaderView::ResizeToContents );
    header->setSectionResizeMode( 0, QHeaderView::Stretch );

    updateButtons();
    // Establish connection here because selection model is destroyed when
    // model changes
    connect( m_ui->partitionTreeView->selectionModel(), &QItemSelectionModel::currentChanged,
             [ this ]( const QModelIndex&, const QModelIndex& )
    {
        updateButtons();
    } );
    connect( model, &QAbstractItemModel::modelReset, this, &PartitionPage::onPartitionModelReset );
}

void
PartitionPage::onPartitionModelReset()
{
    m_ui->partitionTreeView->expandAll();
    updateButtons();
    updateBootLoaderIndex();
}

void
PartitionPage::updateBootLoaderIndex()
{
    // set bootloader back to user selected index
    if ( m_lastSelectedBootLoaderIndex >= 0 && m_ui->bootLoaderComboBox->count() ) {
        m_ui->bootLoaderComboBox->setCurrentIndex( m_lastSelectedBootLoaderIndex );
    }
}

QStringList
PartitionPage::getCurrentUsedMountpoints()
{
    QModelIndex index = m_core->deviceModel()->index(
                            m_ui->deviceComboBox->currentIndex(), 0 );
    if ( !index.isValid() )
        return QStringList();

    Device* device = m_core->deviceModel()->deviceForIndex( index );
    QStringList mountPoints;

    for ( Partition* partition : device->partitionTable()->children() )
    {
        const QString& mountPoint = PartitionInfo::mountPoint( partition );
        if ( !mountPoint.isEmpty() )
            mountPoints << mountPoint;
    }

    return mountPoints;
}

int
PartitionPage::selectedDeviceIndex()
{
    return m_ui->deviceComboBox->currentIndex();
}

void
PartitionPage::selectDeviceByIndex ( int index )
{
        m_ui->deviceComboBox->setCurrentIndex( index );
}