// SPDX-FileCopyrightText: 2020 Simon Persson <simon.persson@mykolab.com>
//
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL

#include "restoredialog.h"
#include "dirselector.h"
#include "kupfiledigger_debug.h"
#include "kuputils.h"
#include "restorejob.h"
#include "ui_restoredialog.h"

#include <KFileUtils>
#include <KFileWidget>
#include <KIO/CopyJob>
#include <KIO/JobUiDelegate>
#include <KIO/JobUiDelegateFactory>
#include <KIO/ListJob>
#include <KIO/OpenUrlJob>
#include <KIO/UDSEntry>
#include <KLocalizedString>
#include <KMessageBox>
#include <KMessageWidget>
#include <KProcess>
#include <KWidgetJobTracker>
#include <QStorageInfo>

#include <QDir>
#include <QInputDialog>
#include <QPushButton>
#include <QTimer>
#include <kio_version.h>
#include <utility>

static const QString cKupTempRestoreFolder = QStringLiteral("_kup_temporary_restore_folder_");

RestoreDialog::RestoreDialog(BupSourceInfo pPathInfo, QWidget *parent)
    : QDialog(parent)
    , mUI(new Ui::RestoreDialog)
    , mSourceInfo(std::move(pPathInfo))
{
    mSourceFileName = mSourceInfo.mPathInRepo.section(QDir::separator(), -1);

    qCDebug(KUPFILEDIGGER) << "Starting restore dialog for repo: " << mSourceInfo.mRepoPath << ", restoring: " << mSourceInfo.mPathInRepo;

    mUI->setupUi(this);

    mFileWidget = nullptr;
    mDirSelector = nullptr;
    mJobTracker = nullptr;

    mUI->mRestoreOriginalButton->setMinimumHeight(mUI->mRestoreOriginalButton->sizeHint().height() * 2);
    mUI->mRestoreCustomButton->setMinimumHeight(mUI->mRestoreCustomButton->sizeHint().height() * 2);

    connect(mUI->mRestoreOriginalButton, SIGNAL(clicked()), SLOT(setOriginalDestination()));
    connect(mUI->mRestoreCustomButton, SIGNAL(clicked()), SLOT(setCustomDestination()));

    mMessageWidget = new KMessageWidget(this);
    mMessageWidget->setWordWrap(true);
    mUI->mTopLevelVLayout->insertWidget(0, mMessageWidget);
    mMessageWidget->hide();
    connect(mUI->mDestBackButton, SIGNAL(clicked()), mMessageWidget, SLOT(hide()));
    connect(mUI->mDestNextButton, SIGNAL(clicked()), SLOT(checkDestinationSelection()));
    connect(mUI->mDestBackButton, &QPushButton::clicked, this, [this] {
        mUI->mStackedWidget->setCurrentIndex(0);
    });
    connect(mUI->mOverwriteBackButton, &QPushButton::clicked, this, [this] {
        mUI->mStackedWidget->setCurrentIndex(0);
    });
    connect(mUI->mConfirmButton, SIGNAL(clicked()), SLOT(fileOverwriteConfirmed()));
    connect(mUI->mOpenDestinationButton, SIGNAL(clicked()), SLOT(openDestinationFolder()));
}

RestoreDialog::~RestoreDialog()
{
    delete mUI;
}

void RestoreDialog::changeEvent(QEvent *pEvent)
{
    QDialog::changeEvent(pEvent);
    switch (pEvent->type()) {
    case QEvent::LanguageChange:
        mUI->retranslateUi(this);
        break;
    default:
        break;
    }
}

void RestoreDialog::setOriginalDestination()
{
    if (mSourceInfo.mIsDirectory) {
        // the path in repo could have had slashes appended below, we are back here because user clicked "back"
        ensureNoTrailingSlash(mSourceInfo.mPathInRepo);
        // select parent of folder to be restored
        mDestination.setFile(mSourceInfo.mPathInRepo.section(QDir::separator(), 0, -2));
    } else {
        mDestination.setFile(mSourceInfo.mPathInRepo);
    }
    startPrechecks();
}

void RestoreDialog::setCustomDestination()
{
    if (mSourceInfo.mIsDirectory && mDirSelector == nullptr) {
        mDirSelector = new DirSelector(this);
        mDirSelector->setRootUrl(QUrl::fromLocalFile(QStringLiteral("/")));
        QString lDirPath = mSourceInfo.mPathInRepo.section(QDir::separator(), 0, -2);
        mDirSelector->expandToUrl(QUrl::fromLocalFile(lDirPath));
        mUI->mDestinationVLayout->insertWidget(0, mDirSelector);

        auto lNewFolderButton = new QPushButton(QIcon::fromTheme(QStringLiteral("folder-new")), xi18nc("@action:button", "New Folder..."));
        connect(lNewFolderButton, SIGNAL(clicked()), SLOT(createNewFolder()));
        mUI->mDestinationHLayout->insertWidget(0, lNewFolderButton);
    } else if (!mSourceInfo.mIsDirectory && mFileWidget == nullptr) {
        QFileInfo lFileInfo(mSourceInfo.mPathInRepo);
        do {
            lFileInfo.setFile(lFileInfo.absolutePath()); // check the file's directory first, not the file.
        } while (!lFileInfo.exists());
        QUrl lStartSelection = QUrl::fromLocalFile(lFileInfo.absoluteFilePath() + '/' + mSourceFileName);
        mFileWidget = new KFileWidget(lStartSelection, this);
        mFileWidget->setOperationMode(KFileWidget::Saving);
        mFileWidget->setMode(KFile::File | KFile::LocalOnly);
        mUI->mDestinationVLayout->insertWidget(0, mFileWidget);
    }
    mUI->mDestNextButton->setFocus();
    mUI->mStackedWidget->setCurrentIndex(1);
}

void RestoreDialog::checkDestinationSelection()
{
    if (mSourceInfo.mIsDirectory) {
        QUrl lUrl = mDirSelector->url();
        if (!lUrl.isEmpty()) {
            mDestination.setFile(lUrl.path());
            startPrechecks();
        } else {
            mMessageWidget->setText(xi18nc("@info message bar appearing on top", "No destination was selected, please select one."));
            mMessageWidget->setMessageType(KMessageWidget::Error);
            mMessageWidget->animatedShow();
        }
    } else {
        connect(mFileWidget, SIGNAL(accepted()), SLOT(checkDestinationSelection2()));
        mFileWidget->slotOk(); // will emit accepted() if selection is valid, continue below then
    }
}

void RestoreDialog::checkDestinationSelection2()
{
    mFileWidget->accept(); // This call is needed for selectedFile() to return something.

    QString lFilePath = mFileWidget->selectedFile();
    if (!lFilePath.isEmpty()) {
        mDestination.setFile(lFilePath);
        startPrechecks();
    } else {
        mMessageWidget->setText(xi18nc("@info message bar appearing on top", "No destination was selected, please select one."));
        mMessageWidget->setMessageType(KMessageWidget::Error);
        mMessageWidget->animatedShow();
    }
}

void RestoreDialog::startPrechecks()
{
    mUI->mFileConflictList->clear();
    mSourceSize = 0;
    mFileSizes.clear();

    qCDebug(KUPFILEDIGGER) << "Destination has been selected: " << mDestination.absoluteFilePath();

    if (mSourceInfo.mIsDirectory) {
        mDirectoriesCount = 1; // the folder being restored, rest will be added during listing.
        mRestorationPath = mDestination.absoluteFilePath();
        mFolderToCreate = QFileInfo(mDestination.absoluteFilePath() + QDir::separator() + mSourceFileName);
        mSavedWorkingDirectory.clear();
        if (mFolderToCreate.exists()) {
            if (mFolderToCreate.isDir()) {
                // destination dir exists, first restore to a subfolder, then move files up.
                mRestorationPath = mFolderToCreate.absoluteFilePath();
                QDir lDir(mFolderToCreate.absoluteFilePath());
                lDir.setFilter(QDir::AllEntries | QDir::Hidden | QDir::System | QDir::NoDotAndDotDot);
                if (lDir.count() > 0) { // destination dir exists and is non-empty.
                    mRestorationPath.append(QDir::separator());
                    mRestorationPath.append(cKupTempRestoreFolder);
                }
                // make bup not restore the source folder itself but instead it's contents
                mSourceInfo.mPathInRepo.append(QDir::separator());
                // folder already exists, need to check for files about to be overwritten.
                // will create QFileInfos with relative paths during listing and compare with listed source entries.
                mSavedWorkingDirectory = QDir::currentPath();
                QDir::setCurrent(mFolderToCreate.absoluteFilePath());
            } else {
                mUI->mFileConflictList->addItem(mFolderToCreate.absoluteFilePath());
                mRestorationPath.append(QDir::separator());
                mRestorationPath.append(cKupTempRestoreFolder);
            }
        }
        qCDebug(KUPFILEDIGGER) << "Starting source file listing job on: " << mSourceInfo.mBupKioPath;
        KIO::ListJob *lListJob = KIO::listRecursive(mSourceInfo.mBupKioPath, KIO::HideProgressInfo);
        auto lJobTracker = new KWidgetJobTracker(this);
        lJobTracker->registerJob(lListJob);
        QWidget *lProgressWidget = lJobTracker->widget(lListJob);
        mUI->mSourceScanLayout->insertWidget(2, lProgressWidget);
        lProgressWidget->show();
        connect(lListJob, &KIO::ListJob::entries, this, &RestoreDialog::collectSourceListing);
        connect(lListJob, &KJob::result, this, &RestoreDialog::sourceListingCompleted);
        lListJob->start();
        mUI->mStackedWidget->setCurrentIndex(4);
    } else {
        mDirectoriesCount = 0;
        mSourceSize = mSourceInfo.mSize;
        mFileSizes.insert(mSourceFileName, mSourceInfo.mSize);
        mRestorationPath = mDestination.absolutePath();
        if (mDestination.exists() || mDestination.fileName() != mSourceFileName) {
            mRestorationPath.append(QDir::separator());
            mRestorationPath.append(cKupTempRestoreFolder);
            if (mDestination.exists()) {
                mUI->mFileConflictList->addItem(mDestination.absoluteFilePath());
            }
        }
        completePrechecks();
    }
}

void RestoreDialog::collectSourceListing(KIO::Job *pJob, const KIO::UDSEntryList &pEntryList)
{
    Q_UNUSED(pJob)
    KIO::UDSEntryList::ConstIterator it = pEntryList.begin();
    const KIO::UDSEntryList::ConstIterator end = pEntryList.end();
    for (; it != end; ++it) {
        QString lEntryName = it->stringValue(KIO::UDSEntry::UDS_NAME);
        if (it->isDir()) {
            if (lEntryName != QStringLiteral(".") && lEntryName != QStringLiteral("..")) {
                mDirectoriesCount++;
            }
        } else {
            if (!it->isLink()) {
                auto lEntrySize = it->numberValue(KIO::UDSEntry::UDS_SIZE);
                mSourceSize += lEntrySize;
                mFileSizes.insert(mSourceFileName + QDir::separator() + lEntryName, lEntrySize);
            }
            if (!mSavedWorkingDirectory.isEmpty()) {
                if (QFileInfo::exists(lEntryName)) {
                    mUI->mFileConflictList->addItem(lEntryName);
                }
            }
        }
    }
}

void RestoreDialog::sourceListingCompleted(KJob *pJob)
{
    qCDebug(KUPFILEDIGGER) << "Source listing job completed. Exit status: " << pJob->error();
    if (!mSavedWorkingDirectory.isEmpty()) {
        QDir::setCurrent(mSavedWorkingDirectory);
    }
    if (pJob->error() != 0) {
        mMessageWidget->setText(
            xi18nc("@info message bar appearing on top", "There was a problem while getting a list of all files to restore: %1", pJob->errorString()));
        mMessageWidget->setMessageType(KMessageWidget::Error);
        mMessageWidget->animatedShow();
        mUI->mStackedWidget->setCurrentIndex(0);
    } else {
        completePrechecks();
    }
}

void RestoreDialog::completePrechecks()
{
    qCDebug(KUPFILEDIGGER) << "Starting free disk space check on: " << mDestination.absolutePath();
    QStorageInfo storageInfo(mDestination.absolutePath());
    if (storageInfo.isValid() && storageInfo.bytesAvailable() < mSourceSize) {
        mMessageWidget->setText(xi18nc("@info message bar appearing on top",
                                       "The destination does not have enough space available. "
                                       "Please choose a different destination or free some space."));
        mMessageWidget->setMessageType(KMessageWidget::Error);
        mMessageWidget->animatedShow();
        mUI->mStackedWidget->setCurrentIndex(0);
    } else if (mUI->mFileConflictList->count() > 0) {
        qCDebug(KUPFILEDIGGER) << "Detected file conflicts.";
        if (mSourceInfo.mIsDirectory) {
            QString lDateString = QLocale().toString(QDateTime::fromSecsSinceEpoch(mSourceInfo.mCommitTime).toLocalTime());
            lDateString.replace(QLatin1Char('/'), QLatin1Char('-')); // make sure no slashes in suggested folder name
            mUI->mNewFolderNameEdit->setText(
                mSourceFileName
                + xi18nc("added to the suggested filename when restoring, %1 is the time when backup was saved", " - saved at %1", lDateString));
            mUI->mConflictTitleLabel->setText(xi18nc("@info", "Folder already exists, please choose a solution"));
        } else {
            mUI->mOverwriteRadioButton->setChecked(true);
            mUI->mOverwriteRadioButton->hide();
            mUI->mNewNameRadioButton->hide();
            mUI->mNewFolderNameEdit->hide();
            mUI->mConflictTitleLabel->setText(xi18nc("@info", "File already exists"));
        }
        mUI->mStackedWidget->setCurrentIndex(2);
    } else {
        startRestoring();
    }
}

void RestoreDialog::fileOverwriteConfirmed()
{
    if (mSourceInfo.mIsDirectory && mUI->mNewNameRadioButton->isChecked()) {
        QFileInfo lNewFolderInfo(mDestination.absoluteFilePath() + QDir::separator() + mUI->mNewFolderNameEdit->text());
        if (lNewFolderInfo.exists()) {
            mMessageWidget->setText(xi18nc("@info message bar appearing on top", "The new name entered already exists, please enter a different one."));
            mMessageWidget->setMessageType(KMessageWidget::Error);
            mMessageWidget->animatedShow();
            return;
        }
        mFolderToCreate = QFileInfo(mDestination.absoluteFilePath() + QDir::separator() + mUI->mNewFolderNameEdit->text());
        mRestorationPath = mFolderToCreate.absoluteFilePath();
        if (!mSourceInfo.mPathInRepo.endsWith(QDir::separator())) {
            mSourceInfo.mPathInRepo.append(QDir::separator());
        }
    }
    startRestoring();
}

void RestoreDialog::startRestoring()
{
    QString lSourcePath(QDir::separator());
    lSourcePath.append(mSourceInfo.mBranchName);
    lSourcePath.append(QDir::separator());
    QDateTime lCommitTime = QDateTime::fromSecsSinceEpoch(mSourceInfo.mCommitTime);
    lSourcePath.append(lCommitTime.toString(QStringLiteral("yyyy-MM-dd-hhmmss")));
    lSourcePath.append(mSourceInfo.mPathInRepo);
    qCDebug(KUPFILEDIGGER) << "Starting restore. Source path: " << lSourcePath << ", restore path: " << mRestorationPath;
    auto lRestoreJob = new RestoreJob(mSourceInfo.mRepoPath, lSourcePath, mRestorationPath, mDirectoriesCount, mSourceSize, mFileSizes);
    if (mJobTracker == nullptr) {
        mJobTracker = new KWidgetJobTracker(this);
    }
    mJobTracker->registerJob(lRestoreJob);
    QWidget *lProgressWidget = mJobTracker->widget(lRestoreJob);
    mUI->mRestoreProgressLayout->insertWidget(2, lProgressWidget);
    lProgressWidget->show();
    connect(lRestoreJob, &KJob::result, this, &RestoreDialog::restoringCompleted);
    lRestoreJob->start();
    mUI->mCloseButton->hide();
    mUI->mStackedWidget->setCurrentIndex(3);
}

void RestoreDialog::restoringCompleted(KJob *pJob)
{
    qCDebug(KUPFILEDIGGER) << "Restore job completed. Exit status: " << pJob->error();
    if (pJob->error() != 0) {
        mUI->mRestorationOutput->setPlainText(pJob->errorText());
        mUI->mRestorationStackWidget->setCurrentIndex(1);
        mUI->mCloseButton->show();
    } else {
        if (!mSourceInfo.mIsDirectory && mSourceFileName != mDestination.fileName()) {
            QUrl lSourceUrl = QUrl::fromLocalFile(mRestorationPath + '/' + mSourceFileName);
            QUrl lDestinationUrl = QUrl::fromLocalFile(mRestorationPath + '/' + mDestination.fileName());
            KIO::CopyJob *lFileMoveJob = KIO::move(lSourceUrl, lDestinationUrl, KIO::HideProgressInfo);
            connect(lFileMoveJob, &KJob::result, this, &RestoreDialog::fileMoveCompleted);
            qCDebug(KUPFILEDIGGER) << "Starting file move job from: " << lSourceUrl << ", to: " << lDestinationUrl;
            lFileMoveJob->start();
        } else {
            moveFolder();
        }
    }
}

void RestoreDialog::fileMoveCompleted(KJob *pJob)
{
    qCDebug(KUPFILEDIGGER) << "File move job completed. Exit status: " << pJob->error();
    if (pJob->error() != 0) {
        mUI->mRestorationOutput->setPlainText(pJob->errorText());
        mUI->mRestorationStackWidget->setCurrentIndex(1);
    } else {
        moveFolder();
    }
}

void RestoreDialog::createNewFolder()
{
    bool lUserAccepted;
    QUrl lUrl = mDirSelector->url();
    QString lNameSuggestion = xi18nc("default folder name when creating a new folder", "New Folder");
    if (QFileInfo::exists(lUrl.adjusted(QUrl::StripTrailingSlash).path() + '/' + lNameSuggestion)) {
        lNameSuggestion = KFileUtils::suggestName(lUrl, lNameSuggestion);
    }

    QString lSelectedName = QInputDialog::getText(this,
                                                  xi18nc("@title:window", "New Folder"),
                                                  xi18nc("@label:textbox", "Create new folder in:\n%1", lUrl.path()),
                                                  QLineEdit::Normal,
                                                  lNameSuggestion,
                                                  &lUserAccepted);

    if (!lUserAccepted)
        return;

    QUrl lPartialUrl(lUrl);
    const QStringList lDirectories = lSelectedName.split(QDir::separator(), Qt::SkipEmptyParts);
    foreach (QString lSubDirectory, lDirectories) {
        QDir lDir(lPartialUrl.path());
        if (lDir.exists(lSubDirectory)) {
            lPartialUrl = lPartialUrl.adjusted(QUrl::StripTrailingSlash);
            lPartialUrl.setPath(lPartialUrl.path() + '/' + (lSubDirectory));
            KMessageBox::error(this, i18n("A folder named %1 already exists.", lPartialUrl.path()));
            return;
        }
        if (!lDir.mkdir(lSubDirectory)) {
            lPartialUrl = lPartialUrl.adjusted(QUrl::StripTrailingSlash);
            lPartialUrl.setPath(lPartialUrl.path() + '/' + (lSubDirectory));
            KMessageBox::error(this, i18n("You do not have permission to create %1.", lPartialUrl.path()));
            return;
        }
        lPartialUrl = lPartialUrl.adjusted(QUrl::StripTrailingSlash);
        lPartialUrl.setPath(lPartialUrl.path() + '/' + (lSubDirectory));
    }
    mDirSelector->expandToUrl(lPartialUrl);
}

void RestoreDialog::openDestinationFolder()
{
    auto *job = new KIO::OpenUrlJob(QUrl::fromLocalFile(mSourceInfo.mIsDirectory ? mFolderToCreate.absoluteFilePath() : mDestination.absolutePath()));
#if KIO_VERSION > QT_VERSION_CHECK(5, 98, 0)
    auto *delegate = KIO::createDefaultJobUiDelegate(KIO::JobUiDelegate::AutoHandlingEnabled, this);
#else
    auto *delegate = new KIO::JobUiDelegate(KIO::JobUiDelegate::AutoHandlingEnabled, this);
#endif
    job->setUiDelegate(delegate);
    job->start();
}

void RestoreDialog::moveFolder()
{
    if (!mRestorationPath.endsWith(cKupTempRestoreFolder)) {
        mUI->mRestorationStackWidget->setCurrentIndex(2);
        mUI->mCloseButton->show();
        qCDebug(KUPFILEDIGGER) << "Overall restore operation completed.";
        return;
    }
    QUrl lSourceUrl = QUrl::fromLocalFile(mRestorationPath);
    QUrl lDestinationUrl = QUrl::fromLocalFile(mRestorationPath.section(QDir::separator(), 0, -2));
    KIO::CopyJob *lFolderMoveJob = KIO::moveAs(lSourceUrl, lDestinationUrl, KIO::Overwrite | KIO::HideProgressInfo);
    connect(lFolderMoveJob, &KJob::result, this, &RestoreDialog::folderMoveCompleted);
    mJobTracker->registerJob(lFolderMoveJob);
    QWidget *lProgressWidget = mJobTracker->widget(lFolderMoveJob);
    mUI->mRestoreProgressLayout->insertWidget(1, lProgressWidget);
    lProgressWidget->show();
    qCDebug(KUPFILEDIGGER) << "Starting folder move job from: " << lSourceUrl << ", to: " << lDestinationUrl;
    lFolderMoveJob->start();
}

void RestoreDialog::folderMoveCompleted(KJob *pJob)
{
    qCDebug(KUPFILEDIGGER) << "Folder move job completed. Exit status: " << pJob->error();
    mUI->mCloseButton->show();
    if (pJob->error() != 0) {
        mUI->mRestorationOutput->setPlainText(pJob->errorText());
        mUI->mRestorationStackWidget->setCurrentIndex(1);
    } else {
        qCDebug(KUPFILEDIGGER) << "Overall restore operation completed.";
        mUI->mRestorationStackWidget->setCurrentIndex(2);
    }
}