#include "mainwindow.h"
#include <QScrollArea>
#include <QDir>
#include <QKeyEvent>
#include <QMenu>
#include <QMenuBar>
#include <QFileDialog>
#include <QStandardPaths>
#include <QMessageBox>
#include <QProgressDialog>
#include <QDebug>
#include <QDockWidget>
#include <signal.h>
#include <unistd.h>
#include <QSettings>
#include <QGuiApplication>
#include <QThreadPool>
#include <QStatusBar>
#include <QImageReader>
#include <QMimeDatabase>
#include "loadrunable.h"
#include "markedfiles.h"
#include "about.h"
#include "statusbar.h"
#include "settingsdialog.h"
#include "histogram.h"

#ifdef __linux__
#include <sys/ioctl.h>
#include <linux/btrfs.h>
#include <sys/socket.h>
#endif

bool moveToTrash(const QString &path);

int MainWindow::socketPair[2] = {0, 0};

MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
{
    qRegisterMetaType<ImageInfoData>("ImageInfoData");
    qRegisterMetaType<std::shared_ptr<RawImage>>("std::shared_ptr<RawImage>");

    SettingsDialog::loadSettings();

    QStringList nameFilter;
    _saveFilter = tr("FITS (*.fits *.fit);;XISF (*.xisf);;");
    _openFilter = tr("Images (");
    QMimeDatabase db;
    auto supportedFormats = QImageReader::supportedMimeTypes();
    QStringList filters;
    for(auto format : supportedFormats)
    {
        QMimeType mimeType = db.mimeTypeForName(format);
        _saveFilter.append(mimeType.filterString() + ";;");
        _openFilter.append("*.");
        _openFilter.append(mimeType.suffixes().join(" *."));
        _openFilter.append(" ");
        nameFilter.append(mimeType.suffixes());
    }
    _openFilter.append("*.fit *.fits *.xisf *.cr2 *.nef *.dng)");
    _openFilter.append(tr(";;All files (*)"));
    nameFilter.append({"fit", "fits", "xisf", "cr2", "nef", "dng"});

    m_info = new ImageInfo(this);
    QDockWidget *infoDock = new QDockWidget(tr("Image info"), this);
    infoDock->setWidget(m_info);
    infoDock->setObjectName("infoDock");
    addDockWidget(Qt::LeftDockWidgetArea, infoDock);
    resize(800, 600);
    setStatusBar(new QStatusBar(this));

    m_database = new Database(this);
    if(!m_database->init())
        QMessageBox::critical(this, tr("Can't open DB"), tr("Can't open SQLITE database"));

    m_imageGL = new ImageScrollAreaGL(m_database, this);
    setCentralWidget(m_imageGL);

    StatusBar *statusBar = new StatusBar(this);
    setStatusBar(statusBar);
    connect(m_imageGL->imageWidget(), &ImageWidget::status, statusBar, &StatusBar::newStatus);

    m_stretchPanel = new StretchToolbar(this);
    connect(m_stretchPanel, &StretchToolbar::paramChanged, m_imageGL->imageWidget(), &ImageWidget::setMTFParams);
    connect(m_stretchPanel, &StretchToolbar::autoStretch, [&](){ m_stretchPanel->stretchImage(m_ringList->currentImage().get()); });
    connect(m_stretchPanel, &StretchToolbar::invert, m_imageGL->imageWidget(), &ImageWidget::invert);
    connect(m_stretchPanel, &StretchToolbar::superPixel, m_imageGL->imageWidget(), &ImageWidget::superPixel);
    connect(m_stretchPanel, &StretchToolbar::falseColor, m_imageGL->imageWidget(), &ImageWidget::falseColor);

    m_ringList = new ImageRingList(m_database, nameFilter, this);
    m_filesystem = new FilesystemWidget(m_ringList, this);
    connect(m_filesystem, SIGNAL(fileSelected(int)), this, SLOT(loadFile(int)));
    connect(m_filesystem, &FilesystemWidget::sortChanged, m_ringList, &ImageRingList::setSort);
    connect(m_filesystem, &FilesystemWidget::reverseSort, m_ringList, &ImageRingList::reverseSort);

    m_filetree = new Filetree(this);
    connect(m_filetree, &Filetree::fileSelected, this, static_cast<void (MainWindow::*)(const QString &)>(&MainWindow::loadFile));
    connect(m_filetree, &Filetree::copyFiles, [this](const QString &path){ copyOrMove(true, path); });
    connect(m_filetree, &Filetree::moveFiles, [this](const QString &path){ copyOrMove(false, path); });
    connect(m_filetree, &Filetree::indexDirectory, this, static_cast<void (MainWindow::*)(const QString &)>(&MainWindow::indexDir));

    m_databaseView = new DataBaseView(m_database, this);
    connect(m_databaseView, SIGNAL(loadFile(QString)), this, SLOT(loadFile(QString)));

    addToolBar(Qt::TopToolBarArea, m_stretchPanel);

    QDockWidget *filesystemDock = new QDockWidget(tr("Filesystem"), this);
    filesystemDock->setWidget(m_filesystem);
    filesystemDock->setObjectName("filesystemDock");
    addDockWidget(Qt::LeftDockWidgetArea, filesystemDock);

    QDockWidget *databaseViewDock = new QDockWidget(tr("FITS/XISF files database"), this);
    databaseViewDock->setWidget(m_databaseView);
    databaseViewDock->setObjectName("databaseViewDock");
    databaseViewDock->hide();
    addDockWidget(Qt::BottomDockWidgetArea, databaseViewDock);

    QDockWidget *filetreeDock = new QDockWidget(tr("File tree"), this);
    filetreeDock->setWidget(m_filetree);
    filetreeDock->setObjectName("filetreeDock");
    databaseViewDock->hide();
    addDockWidget(Qt::LeftDockWidgetArea, filetreeDock);

    Histogram *histogram = new Histogram(this);
    QDockWidget *histogramDock = new QDockWidget(tr("Histogram"), this);
    histogramDock->setWidget(histogram);
    histogramDock->setObjectName("histogramDock");
    histogramDock->hide();
    addDockWidget(Qt::LeftDockWidgetArea, histogramDock);

    setWindowTitle(tr("Tenmon"));

    connect(m_ringList, SIGNAL(pixmapLoaded(Image*)), this, SLOT(pixmapLoaded(Image*)));
    connect(m_ringList, SIGNAL(currentImageChanged(int)), this, SLOT(updateWindowTitle()));
    connect(m_ringList, SIGNAL(infoLoaded(ImageInfoData)), m_info, SLOT(setInfo(const ImageInfoData&)));
    connect(m_ringList, SIGNAL(currentImageChanged(int)), m_filesystem, SLOT(selectFile(int)));
    connect(m_ringList, &ImageRingList::thumbnailLoaded, m_imageGL->imageWidget(), &ImageWidget::thumbnailLoaded);
    connect(m_ringList, &ImageRingList::pixmapLoaded, m_stretchPanel, &StretchToolbar::imageLoaded);
    connect(m_ringList, &ImageRingList::pixmapLoaded, histogram, &Histogram::imageLoaded);
    connect(m_imageGL->imageWidget(), &ImageWidget::fileDropped, this, static_cast<void (MainWindow::*)(const QString &)>(&MainWindow::loadFile));

    QMenu *fileMenu = new QMenu(tr("File"), this);
    fileMenu->addAction(tr("Open"), this, SLOT(loadFile()), QKeySequence::Open);
    fileMenu->addAction(tr("Save as"), this, SLOT(saveAs()), QKeySequence::Save);
    fileMenu->addSeparator();
    fileMenu->addAction(tr("Copy marked files"), this, SLOT(copyMarked()), Qt::Key_F5);
    fileMenu->addAction(tr("Move marked files"), this, SLOT(moveMarked()), Qt::Key_F6);
    fileMenu->addAction(tr("Move marked files to trash"), this, &MainWindow::deleteMarked, QKeySequence::Delete);
    fileMenu->addSeparator();
    fileMenu->addAction(tr("Index directory"), this, SLOT(indexDir()));
    fileMenu->addAction(tr("Reindex files"), this, SLOT(reindex()));
    fileMenu->addAction(tr("Export database to CSV"), this, &MainWindow::exportCSV);
    fileMenu->addSeparator();
    QAction *liveModeAction = fileMenu->addAction(tr("Live mode"), this, SLOT(liveMode(bool)));
    liveModeAction->setCheckable(true);
    QAction *exitAction = fileMenu->addAction(tr("Exit"), this, SLOT(close()));
    exitAction->setShortcut(QKeySequence::Quit);
    menuBar()->addMenu(fileMenu);

    QMenu *editMenu = new QMenu(tr("Edit"), this);
    editMenu->addAction(tr("Settings"), this, &MainWindow::showSettingsDialog);
    menuBar()->addMenu(editMenu);

    QMenu *viewMenu = new QMenu(tr("View"), this);
    viewMenu->addAction(tr("Zoom In"), m_imageGL, SLOT(zoomIn()), QKeySequence::ZoomIn);
    viewMenu->addAction(tr("Zoom Out"), m_imageGL, SLOT(zoomOut()), QKeySequence::ZoomOut);
    viewMenu->addAction(tr("Best Fit"), m_imageGL, SLOT(bestFit()), QKeySequence("Ctrl+1"));
    viewMenu->addAction(tr("100%"), m_imageGL, SLOT(oneToOne()));
    QAction *thumbnailsAction = viewMenu->addAction(tr("Thumbnails"), [this](bool checked){
        if(SettingsDialog::loadThumbsizes())m_ringList->clearThumbnails();
        m_imageGL->imageWidget()->allocateThumbnails(m_ringList->imageNames());
        m_imageGL->imageWidget()->showThumbnail(checked);
        if(checked)m_ringList->loadThumbnails();
        else m_ringList->stopLoading();
    }, Qt::Key_F2);
    thumbnailsAction->setCheckable(true);
    menuBar()->addMenu(viewMenu);

    QMenu *selectMenu = new QMenu(tr("Select"), this);
    selectMenu->addAction(tr("Mark"), this, SLOT(markImage()), Qt::Key_F7);
    selectMenu->addAction(tr("Unmark"), this, SLOT(unmarkImage()), Qt::Key_F8);
    selectMenu->addSeparator();
    selectMenu->addAction(tr("Mark and next"), this, SLOT(markAndNext()), Qt::Key_M);
    selectMenu->addAction(tr("Unmark and next"), this, SLOT(unmarkAndNext()), Qt::Key_X);
    selectMenu->addAction(tr("Show marked"), this, &MainWindow::showMarkFilesDialog);
    menuBar()->addMenu(selectMenu);

    QMenu *analyzeMenu = new QMenu(tr("Analyze"), this);
    QActionGroup *analyzeGroup = new QActionGroup(this);
    connect(analyzeGroup, &QActionGroup::triggered, [](QAction* action) {
        static QAction* lastAction = nullptr;
        if(action == lastAction)
        {
            action->setChecked(false);
            lastAction = nullptr;
        }
        else
            lastAction = action;
        });

    QAction *statsAction = analyzeGroup->addAction(tr("Image statistics"));
    QAction *peakAction = analyzeGroup->addAction(tr("Peak finder"));
    QAction *starAction = analyzeGroup->addAction(tr("Star finder"));
    statsAction->setCheckable(true);
    peakAction->setCheckable(true);
    starAction->setCheckable(true);
    connect(statsAction, SIGNAL(toggled(bool)), this, SLOT(imageStats(bool)));
    connect(peakAction, SIGNAL(toggled(bool)), this, SLOT(peakFinder(bool)));
    connect(starAction, SIGNAL(toggled(bool)), this, SLOT(starFinder(bool)));
    analyzeMenu->addActions({statsAction, peakAction, starAction});
    //menuBar()->addMenu(analyzeMenu);

    QMenu *dockMenu = new QMenu(tr("Docks"), this);
    dockMenu->addAction(infoDock->toggleViewAction());
    dockMenu->addAction(m_stretchPanel->toggleViewAction());
    dockMenu->addAction(filesystemDock->toggleViewAction());
    dockMenu->addAction(databaseViewDock->toggleViewAction());
    dockMenu->addAction(filetreeDock->toggleViewAction());
    dockMenu->addAction(histogramDock->toggleViewAction());
    menuBar()->addMenu(dockMenu);

    QMenu *helpMenu = menuBar()->addMenu(tr("Help"));
    helpMenu->addAction(tr("Help"), [this]{ HelpDialog help(this); help.exec(); }, QKeySequence::HelpContents);
    helpMenu->addAction(tr("About Tenmon"), [this]{ About about(this); about.exec(); });
    helpMenu->addAction(tr("About Qt"), [this](){ QMessageBox::aboutQt(this); });

    setupSigterm();
    QSettings settings;
    restoreGeometry(settings.value("mainwindow/geometry").toByteArray());
    restoreState(settings.value("mainwindow/state").toByteArray());

    QStringList standardLocations = QStandardPaths::standardLocations(QStandardPaths::PicturesLocation);
    if(standardLocations.size())
        _lastDir = standardLocations.first();

    _lastDir = settings.value("mainwindow/lastdir", _lastDir).toString();

    QStringList args = QCoreApplication::arguments();
    args.removeFirst();
    for(auto &arg : args)
    {
        QFileInfo info(arg);
        if(info.exists())
        {
            m_ringList->setFile(info.canonicalFilePath());
            updateWindowTitle();
            _lastDir = info.absoluteDir().absolutePath();
            settings.setValue("mainwindow/lastdir", _lastDir);
            break;
        }
    }

    m_imageGL->setFocus();

    // workaround for nasty wayland backend bug https://bugreports.qt.io/browse/QTBUG-87332
    if(static_cast<QGuiApplication*>(QCoreApplication::instance())->platformName() == "wayland")
    {
        infoDock->setFeatures(QDockWidget::DockWidgetClosable | QDockWidget::DockWidgetMovable);
        filesystemDock->setFeatures(QDockWidget::DockWidgetClosable | QDockWidget::DockWidgetMovable);
        databaseViewDock->setFeatures(QDockWidget::DockWidgetClosable | QDockWidget::DockWidgetMovable);
        filetreeDock->setFeatures(QDockWidget::DockWidgetClosable | QDockWidget::DockWidgetMovable);
        m_stretchPanel->setFloatable(false);
    }
}

MainWindow::~MainWindow()
{
    delete m_database;
}

void MainWindow::keyPressEvent(QKeyEvent *event)
{
    switch (event->key())
    {
    case Qt::Key_Left:
    case Qt::Key_Up:
        m_ringList->decrement();
        break;
    case Qt::Key_Right:
    case Qt::Key_Down:
        m_ringList->increment();
        break;
    default:
        event->ignore();
        break;
    }

    if(event->isAccepted())
        updateWindowTitle();
}

void MainWindow::keyReleaseEvent(QKeyEvent *event)
{
    event->ignore();
}

void MainWindow::setupSigterm()
{
#ifdef __linux__
    struct sigaction signal;

    signal.sa_handler = MainWindow::signalHandler;
    sigemptyset(&signal.sa_mask);
    signal.sa_flags = 0;
    signal.sa_flags |= SA_RESTART;

    sigaction(SIGHUP, &signal, 0);
    sigaction(SIGTERM, &signal, 0);
    sigaction(SIGINT, &signal, 0);

    ::socketpair(AF_UNIX, SOCK_STREAM, 0, socketPair);
    socketNotifier = new QSocketNotifier(socketPair[1], QSocketNotifier::Read, this);
    connect(socketNotifier, SIGNAL(activated(int)), this, SLOT(socketNotify()));
#endif
}

void MainWindow::signalHandler(int)
{
    char a = 1;
    ::write(socketPair[0], &a, sizeof(a));
}

void MainWindow::closeEvent(QCloseEvent *event)
{
    QSettings settings;
    settings.setValue("mainwindow/geometry", saveGeometry());
    settings.setValue("mainwindow/state", saveState());
    QMainWindow::closeEvent(event);
}

void MainWindow::copyOrMove(bool copy)
{
    QString dest = QFileDialog::getExistingDirectory(this,
                                                     tr("Select destination"),
                                                     _lastDir,
                                                     QFileDialog::ShowDirsOnly);
    copyOrMove(copy, dest);
}

void MainWindow::copyOrMove(bool copy, const QString &dest)
{
    QDir dir(dest);
    if(!dest.isEmpty() && dir.exists())
    {
        int i = 0;
        QStringList files = m_database->getMarkedFiles();
        QProgressDialog progress(copy ? tr("Copying") : tr("Moving"), tr("Cancel"), 0, files.size(), this);
        progress.setWindowModality(Qt::WindowModal);
        progress.show();
        for(const QString &file : files)
        {
            bool result = false;
            QFileInfo info(file);
            QFile srcFile(file);
            QFile dstFile(dir.absoluteFilePath(info.fileName()));

            if(dstFile.exists())
                continue;

            if(progress.wasCanceled())
                return;
#ifdef __linux__
            if(copy)
            {
                srcFile.open(QIODevice::ReadOnly);
                dstFile.open(QIODevice::WriteOnly);
                if(ioctl(dstFile.handle(), BTRFS_IOC_CLONE, srcFile.handle()) < 0)
                {
                    dstFile.remove();
                    dstFile.close();
                    result = srcFile.copy(dstFile.fileName());
                }
                else result = true;
            }
            else
            {
                result = srcFile.rename(dstFile.fileName());
            }
#else
            if(copy)
                result = srcFile.copy(dstFile.fileName());
            else
                result = srcFile.rename(dstFile.fileName());
#endif
            if(!result)
            {
                QString t = copy ? tr("Failed to copy") : tr("Failed to move");
                QString m = copy ? tr("Failed to copy from %1 to %2") : tr("Failed to move from %1 to %2");
                QMessageBox::StandardButton button = QMessageBox::warning(this, t,
                                                                          m.arg(srcFile.fileName()).arg(dir.absolutePath()),
                                                                          QMessageBox::Ignore | QMessageBox::Abort);
                if(button == QMessageBox::Abort)return;
            }
            progress.setValue(i++);
        }
        m_database->clearMarkedFiles();
    }
}

void MainWindow::socketNotify()
{
    socketNotifier->setEnabled(false);
    char tmp;
    read(socketPair[1], &tmp, sizeof(tmp));
    close();
    socketNotifier->setEnabled(true);
}

void MainWindow::pixmapLoaded(Image *image)
{
    if(image->rawImage())
    {
        m_imageGL->setImage(image);
    }
}

void MainWindow::loadFile()
{
    QString file = QFileDialog::getOpenFileName(this,
                                                tr("Open file"),
                                                _lastDir,
                                                _openFilter);
    loadFile(file);
}

void MainWindow::loadFile(const QString &path)
{
    if(!path.isEmpty())
    {
        QFileInfo info(path);
        m_ringList->setFile(info.canonicalFilePath());
        updateWindowTitle();
        if(info.isDir())
            _lastDir = info.absolutePath();
        else
            _lastDir = info.canonicalPath();
        QSettings settings;
        settings.setValue("mainwindow/lastdir", _lastDir);
    }
}

void MainWindow::loadFile(int row)
{
    m_ringList->loadFile(row);
}

void MainWindow::indexDir()
{
    QString dir = QFileDialog::getExistingDirectory(this, tr("Index directory"), _lastDir, QFileDialog::ShowDirsOnly);
    indexDir(dir);
}

void MainWindow::indexDir(const QString &dir)
{
    if(!dir.isEmpty())
    {
        QProgressDialog progressDialog(tr("Indexing FITS files"), tr("Cancel"), 0, 1, this);
        progressDialog.setModal(true);
        m_database->indexDir(dir, &progressDialog);
    }
}

void MainWindow::reindex()
{
    QProgressDialog progressDialog(tr("Indexing FITS files"), tr("Cancel"), 0, 1, this);
    progressDialog.setModal(true);
    m_database->reindex(&progressDialog);
}

void MainWindow::saveAs()
{
    QString selectedFilter;
    QString file = QFileDialog::getSaveFileName(this,
                                 tr("Save as"),
                                 _lastDir,
                                 _saveFilter,
                                 &selectedFilter);
    auto filterToFormat = [](const QString &file, const QString &filter) -> const char*
    {
        QString suffix = QFileInfo(file).suffix();
        if(!suffix.compare("jpg", Qt::CaseInsensitive) || !suffix.compare("jpeg", Qt::CaseInsensitive))return "JPEG";
        if(!suffix.compare("png", Qt::CaseInsensitive))return "PNG";
        if(!suffix.compare("fits", Qt::CaseInsensitive) || !suffix.compare("fit", Qt::CaseInsensitive))return "FITS";
        if(!suffix.compare("xisf", Qt::CaseInsensitive))return "XISF";
        if(filter.contains("png"))return "PNG";
        if(filter.contains("fits"))return "FITS";
        if(filter.contains("xisf"))return "XISF";
        return "JPEG";
    };

    if(!file.isEmpty())
    {
        QString format = filterToFormat(file, selectedFilter);

        if(format == "FITS" || format == "XISF")
        {
            convert(file, format);
        }
        else
        {
            QImage img = m_imageGL->imageWidget()->renderToImage();
            if(!img.isNull())
                img.save(file, filterToFormat(file, selectedFilter));
        }
    }
}

void MainWindow::convert(const QString &outfile, const QString &format)
{
    QString file = m_ringList->currentImage()->name();
    QThreadPool::globalInstance()->start(new ConvertRunable(file, outfile, format));
}

void MainWindow::markImage()
{
    ImagePtr ptr = m_ringList->currentImage();
    if(ptr)
    {
        QString file = ptr->name();
        if(!file.isEmpty())
        {
            m_database->mark(file);
            m_ringList->updateMark();
        }

        updateWindowTitle();
    }
}

void MainWindow::unmarkImage()
{
    ImagePtr ptr = m_ringList->currentImage();
    if(ptr)
    {
        QString file = ptr->name();
        if(!file.isEmpty())
        {
            m_database->unmark(file);
            m_ringList->updateMark();
        }

        updateWindowTitle();
    }
}

void MainWindow::markAndNext()
{
    markImage();
    m_ringList->increment();
    updateWindowTitle();
}

void MainWindow::unmarkAndNext()
{
    unmarkImage();
    m_ringList->increment();
    updateWindowTitle();
}

void MainWindow::copyMarked()
{
    copyOrMove(true);
}

void MainWindow::moveMarked()
{
    copyOrMove(false);
}

void MainWindow::deleteMarked()
{
    QStringList files = m_database->getMarkedFiles();
    if(QMessageBox::question(this, tr("Move files to trash?"), tr("Do you want to move %1 files to trash?").arg(files.size())) != QMessageBox::Yes)
        return;

    QProgressDialog progress(tr("Moving marked files to trash"), tr("Cancel"), 0, files.size(), this);
    progress.setWindowModality(Qt::WindowModal);
    progress.show();
    int i = 0;
    for(const QString &file : files)
    {
        if(!QFile::exists(file))
            continue;

        if(progress.wasCanceled())
            return;

        if(!moveToTrash(file))
        {
            QMessageBox::warning(this, tr("Failed to move file to trash"), tr("Failed to move file to trash %1").arg(file));
            return;
        }
        progress.setValue(i++);
    }
    m_database->clearMarkedFiles();
}

void MainWindow::liveMode(bool active)
{
    m_ringList->setLiveMode(active);
}

void MainWindow::imageStats(bool imageStats)
{
    m_ringList->setCalculateStats(imageStats);
}

void MainWindow::peakFinder(bool findPeaks)
{
    m_ringList->setFindPeaks(findPeaks);
}

void MainWindow::starFinder(bool findStars)
{
    m_ringList->setFindStars(findStars);
}

void MainWindow::showMarkFilesDialog()
{
    MarkedFiles markedFiles(this);
    markedFiles.exec();
}

void MainWindow::showSettingsDialog()
{
    SettingsDialog settingsDialog(this);
    connect(&settingsDialog, &SettingsDialog::preloadChanged, m_ringList, &ImageRingList::setPreload);
    settingsDialog.exec();
}

void MainWindow::exportCSV()
{
    QStringList documentDir = QStandardPaths::standardLocations(QStandardPaths::DocumentsLocation);
    if(documentDir.empty())documentDir.append("");
    QString file = QFileDialog::getSaveFileName(this,
                                 tr("Save as"),
                                 documentDir.first(),
                                 tr("CSV file (*.csv)"));

    if(!file.isEmpty())
        m_databaseView->exportCSV(file);
}

void MainWindow::updateWindowTitle()
{
    ImagePtr ptr = m_ringList->currentImage();
    if(ptr)
    {
        QFileInfo info(ptr->name());
        QString title = info.fileName();
        if(m_database->isMarked(ptr->name()))
                title += " *";
        setWindowTitle(title);
    }
}