#include <QAction>
#include <QApplication>
#include <QCheckBox>
#include <QComboBox>
#include <QDialog>
#include <QDialogButtonBox>
#include <QFileDialog>
#include <QFileInfo>
#include <QFont>
#include <QFormLayout>
#include <QFrame>
#include <QGroupBox>
#include <QHBoxLayout>
#include <QLabel>
#include <QLineEdit>
#include <QMainWindow>
#include <QMap>
#include <QMenuBar>
#include <QMessageBox>
#include <QPalette>
#include <QPushButton>
#include <QRadioButton>
#include <QRegExp>
#include <QScrollArea>
#include <QStatusBar>
#include <QStyle>
#include <QTreeWidget>
#include <QVBoxLayout>

namespace {

struct Board {
    QString name;
    QString platform;
};

QVector<Board> parseBoards(const QString &text) {
    QVector<Board> boards;
    QString platform = QStringLiteral("Other");
    for (const QString &rawLine : text.split('\n')) {
        const QString line = rawLine.trimmed();
        if (line.isEmpty())
            continue;
        if (line.endsWith(':')) {
            platform = line.left(line.size() - 1);
            continue;
        }
        for (const QString &name : line.split(QRegExp(QStringLiteral("\\s+")), Qt::SkipEmptyParts))
            boards.push_back({name, platform});
    }
    return boards;
}

QLabel *description(const QString &text) {
    auto *label = new QLabel(text);
    label->setWordWrap(true);
    label->setForegroundRole(QPalette::Mid);
    return label;
}

QGroupBox *group(const QString &title, QLayout *layout) {
    auto *box = new QGroupBox(title);
    box->setLayout(layout);
    return box;
}

class BoardDialog final : public QDialog {
public:
    explicit BoardDialog(const QVector<Board> &boards, QWidget *parent = nullptr)
        : QDialog(parent), boards_(boards) {
        setWindowTitle(tr("Select Target Board"));
        resize(620, 620);
        setModal(true);

        auto *layout = new QVBoxLayout(this);
        search_ = new QLineEdit;
        search_->setPlaceholderText(tr("Search boards, platforms, or architectures…"));
        search_->setClearButtonEnabled(true);
        tree_ = new QTreeWidget;
        tree_->setHeaderHidden(true);
        tree_->setRootIsDecorated(true);
        tree_->setAlternatingRowColors(true);
        tree_->setUniformRowHeights(true);
        layout->addWidget(search_);
        layout->addWidget(tree_, 1);

        auto *buttons = new QDialogButtonBox(QDialogButtonBox::Cancel);
        layout->addWidget(buttons);
        connect(buttons, &QDialogButtonBox::rejected, this, &QDialog::reject);
        connect(search_, &QLineEdit::textChanged, this, [this](const QString &text) { populate(text); });
        connect(tree_, &QTreeWidget::itemActivated, this, [this](QTreeWidgetItem *item) {
            if (item && item->parent()) {
                selectedName_ = item->data(0, Qt::UserRole).toString();
                selectedPlatform_ = item->parent()->text(0);
                accept();
            }
        });
        populate({});
    }

    QString selectedName() const { return selectedName_; }
    QString selectedPlatform() const { return selectedPlatform_; }

private:
    void populate(const QString &query) {
        tree_->clear();
        QMap<QString, QTreeWidgetItem *> headings;
        const QString needle = query.trimmed();
        for (const Board &board : boards_) {
            if (!needle.isEmpty() && !board.name.contains(needle, Qt::CaseInsensitive)
                && !board.platform.contains(needle, Qt::CaseInsensitive))
                continue;
            auto *&heading = headings[board.platform];
            if (!heading) {
                heading = new QTreeWidgetItem(tree_, {board.platform});
                QFont font = heading->font(0);
                font.setBold(true);
                heading->setFont(0, font);
                heading->setFlags(heading->flags() & ~Qt::ItemIsSelectable);
            }
            auto *item = new QTreeWidgetItem(heading, {board.name});
            item->setData(0, Qt::UserRole, board.name);
        }
        tree_->expandAll();
        if (!query.isEmpty() && tree_->topLevelItemCount() > 0) {
            auto *heading = tree_->topLevelItem(0);
            if (heading->childCount() > 0)
                tree_->setCurrentItem(heading->child(0));
        }
    }

    QVector<Board> boards_;
    QLineEdit *search_ = nullptr;
    QTreeWidget *tree_ = nullptr;
    QString selectedName_;
    QString selectedPlatform_;
};

class MainWindow final : public QMainWindow {
public:
    MainWindow(const QString &boardsText, const QString &drivesText)
        : boards_(parseBoards(boardsText)) {
        setWindowTitle(tr("ALT Image Writer"));
        resize(780, 820);
        setMinimumSize(620, 600);

        auto *about = menuBar()->addMenu(tr("&Help"))->addAction(tr("&About"));
        connect(about, &QAction::triggered, this, [this] {
            QMessageBox::about(this, tr("About ALT Image Writer"),
                tr("<h3>ALT Image Writer</h3><p>Version 0.1.0</p>"
                   "<p>Prepare ALT Linux installation media for supported "
                   "single-board computers.</p>"));
        });

        auto *scroll = new QScrollArea;
        scroll->setWidgetResizable(true);
        scroll->setFrameShape(QFrame::NoFrame);
        setCentralWidget(scroll);

        auto *viewport = new QWidget;
        auto *outer = new QHBoxLayout(viewport);
        outer->setContentsMargins(20, 20, 20, 20);
        auto *content = new QWidget;
        content->setMaximumWidth(700);
        auto *layout = new QVBoxLayout(content);
        layout->setSpacing(16);
        outer->addStretch();
        outer->addWidget(content, 1);
        outer->addStretch();
        scroll->setWidget(viewport);

        auto *title = new QLabel(tr("Create Installation Media"));
        QFont titleFont = title->font();
        titleFont.setPointSize(titleFont.pointSize() + 7);
        titleFont.setBold(true);
        title->setFont(titleFont);
        title->setAlignment(Qt::AlignCenter);
        layout->addWidget(title);
        auto *intro = description(tr("Prepare an ALT Linux root filesystem or disk image for your board."));
        intro->setAlignment(Qt::AlignCenter);
        layout->addWidget(intro);

        createSource(layout);
        createHardware(layout);
        createDestination(layout, drivesText);
        createOptions(layout);
        layout->addStretch();

        auto *bar = new QWidget;
        auto *barLayout = new QHBoxLayout(bar);
        barLayout->setContentsMargins(12, 8, 12, 8);
        barLayout->addWidget(description(tr("Nothing will be written until you confirm.")), 1);
        writeButton_ = new QPushButton(tr("Review and Write"));
        writeButton_->setDefault(true);
        writeButton_->setEnabled(false);
        barLayout->addWidget(writeButton_);
        statusBar()->addPermanentWidget(bar, 1);
        connect(writeButton_, &QPushButton::clicked, this, [this] { review(); });
    }

private:
    void createSource(QVBoxLayout *page) {
        auto *layout = new QVBoxLayout;
        layout->addWidget(description(tr("Choose a root filesystem archive or a ready-made disk image.")));
        auto *types = new QHBoxLayout;
        types->addWidget(new QLabel(tr("Source type")));
        types->addStretch();
        rootfsButton_ = new QRadioButton(tr("Root filesystem"));
        imageButton_ = new QRadioButton(tr("Disk image"));
        rootfsButton_->setChecked(true);
        types->addWidget(rootfsButton_);
        types->addWidget(imageButton_);
        layout->addLayout(types);

        auto *picker = new QHBoxLayout;
        sourceLabel_ = new QLabel(tr("No source selected"));
        sourceLabel_->setTextInteractionFlags(Qt::TextSelectableByMouse);
        auto *choose = new QPushButton(tr("Choose…"));
        choose->setIcon(style()->standardIcon(QStyle::SP_DialogOpenButton));
        picker->addWidget(sourceLabel_, 1);
        picker->addWidget(choose);
        layout->addLayout(picker);
        sourceHint_ = description(tr("Supported: .tar, .tar.gz, .tar.xz"));
        layout->addWidget(sourceHint_);
        page->addWidget(group(tr("Installation Source"), layout));

        connect(rootfsButton_, &QRadioButton::toggled, this, [this](bool checked) {
            if (checked) {
                sourceHint_->setText(tr("Supported: .tar, .tar.gz, .tar.xz"));
                fileOutputButton_->setEnabled(true);
            }
        });
        connect(imageButton_, &QRadioButton::toggled, this, [this](bool checked) {
            if (checked) {
                sourceHint_->setText(tr("Supported: .img, .img.xz"));
                driveOutputButton_->setChecked(true);
                fileOutputButton_->setEnabled(false);
            }
        });
        connect(choose, &QPushButton::clicked, this, [this] {
            const QString filter = imageButton_->isChecked()
                ? tr("Disk images (*.img *.img.xz);;All files (*)")
                : tr("Root filesystem archives (*.tar *.tar.gz *.tar.xz);;All files (*)");
            const QString path = QFileDialog::getOpenFileName(this, tr("Choose Installation Source"), {}, filter);
            if (!path.isEmpty()) {
                sourcePath_ = path;
                sourceLabel_->setText(QFileInfo(path).fileName());
                sourceLabel_->setToolTip(path);
                sourceHint_->setText(QFileInfo(path).absolutePath());
                updateReady();
            }
        });
    }

    void createHardware(QVBoxLayout *page) {
        auto *layout = new QVBoxLayout;
        layout->addWidget(description(tr("Boards are grouped by platform, SoC family, and architecture.")));
        auto *row = new QHBoxLayout;
        auto *labels = new QVBoxLayout;
        boardLabel_ = new QLabel(tr("No board selected"));
        boardHint_ = description(tr("Choose from %1 supported boards").arg(boards_.size()));
        labels->addWidget(boardLabel_);
        labels->addWidget(boardHint_);
        auto *select = new QPushButton(tr("Select Board…"));
        row->addLayout(labels, 1);
        row->addWidget(select);
        layout->addLayout(row);
        page->addWidget(group(tr("Target Hardware"), layout));

        connect(select, &QPushButton::clicked, this, [this] {
            BoardDialog dialog(boards_, this);
            if (dialog.exec() == QDialog::Accepted) {
                selectedBoard_ = dialog.selectedName();
                selectedPlatform_ = dialog.selectedPlatform();
                boardLabel_->setText(selectedBoard_);
                QFont font = boardLabel_->font();
                font.setBold(true);
                boardLabel_->setFont(font);
                boardHint_->setText(selectedPlatform_);
                updateReady();
            }
        });
    }

    void createDestination(QVBoxLayout *page, const QString &drivesText) {
        auto *layout = new QVBoxLayout;
        layout->addWidget(description(tr("Write to removable media or create an image file.")));
        auto *types = new QHBoxLayout;
        types->addWidget(new QLabel(tr("Output type")));
        types->addStretch();
        driveOutputButton_ = new QRadioButton(tr("Drive"));
        fileOutputButton_ = new QRadioButton(tr("Image file"));
        driveOutputButton_->setChecked(true);
        types->addWidget(driveOutputButton_);
        types->addWidget(fileOutputButton_);
        layout->addLayout(types);

        driveRow_ = new QWidget;
        auto *driveLayout = new QFormLayout(driveRow_);
        driveBox_ = new QComboBox;
        const QStringList drives = drivesText.split('\n', Qt::SkipEmptyParts);
        driveBox_->addItems(drives);
        if (drives.isEmpty()) {
            driveBox_->addItem(tr("No removable drives detected"));
            driveBox_->setEnabled(false);
        }
        driveLayout->addRow(tr("Storage device"), driveBox_);
        layout->addWidget(driveRow_);

        fileRow_ = new QWidget;
        auto *fileLayout = new QHBoxLayout(fileRow_);
        fileLayout->setContentsMargins(0, 0, 0, 0);
        outputLabel_ = new QLabel(tr("Choose where to save the image"));
        auto *choose = new QPushButton(tr("Choose…"));
        choose->setIcon(style()->standardIcon(QStyle::SP_DialogSaveButton));
        fileLayout->addWidget(outputLabel_, 1);
        fileLayout->addWidget(choose);
        fileRow_->hide();
        layout->addWidget(fileRow_);
        page->addWidget(group(tr("Destination"), layout));

        connect(driveOutputButton_, &QRadioButton::toggled, this, [this](bool checked) {
            driveRow_->setVisible(checked);
            fileRow_->setVisible(!checked);
            updateReady();
        });
        connect(choose, &QPushButton::clicked, this, [this] {
            const QString path = QFileDialog::getSaveFileName(this, tr("Create Disk Image"),
                QStringLiteral("alt-linux.img"), tr("Raw disk images (*.img);;All files (*)"));
            if (!path.isEmpty()) {
                outputPath_ = path;
                outputLabel_->setText(QFileInfo(path).fileName());
                outputLabel_->setToolTip(path);
                updateReady();
            }
        });
    }

    void createOptions(QVBoxLayout *page) {
        auto *layout = new QFormLayout;
        auto *filesystem = new QComboBox;
        filesystem->addItems({QStringLiteral("ext4"), QStringLiteral("f2fs")});
        layout->addRow(tr("Root filesystem"), filesystem);
        auto *resize = new QCheckBox(tr("Grow to fill the destination"));
        resize->setChecked(true);
        layout->addRow(tr("Resize root partition"), resize);
        layout->addRow(tr("Boot partition"), new QCheckBox(tr("Create a separate 512 MiB partition")));
        layout->addRow(tr("Encryption"), new QCheckBox(tr("Encrypt root partition with LUKS")));
        layout->addRow(tr("Serial console"), new QCheckBox(tr("Add to boot arguments")));
        auto *efi = new QComboBox;
        efi->addItems({tr("None"), tr("EFI (GPT)"), tr("EFI (MBR)")});
        layout->addRow(tr("EFI system partition"), efi);
        auto *vnc = new QComboBox;
        vnc->addItems({tr("Use image default"), tr("Enabled"), tr("Disabled")});
        layout->addRow(tr("First-boot VNC"), vnc);
        page->addWidget(group(tr("Options"), layout));
    }

    void updateReady() {
        const bool destination = driveOutputButton_->isChecked()
            ? driveBox_->isEnabled() && driveBox_->currentIndex() >= 0
            : !outputPath_.isEmpty();
        writeButton_->setEnabled(!sourcePath_.isEmpty() && !selectedBoard_.isEmpty() && destination);
    }

    void review() {
        const QString destination = driveOutputButton_->isChecked() ? driveBox_->currentText() : outputPath_;
        QMessageBox dialog(QMessageBox::Warning, tr("Ready to write?"),
            tr("Board: %1\nPlatform: %2\nDestination: %3\n\n"
               "This is an interface preview. No data will be written.")
                .arg(selectedBoard_, selectedPlatform_, destination),
            QMessageBox::Cancel | QMessageBox::Ok, this);
        dialog.setDefaultButton(QMessageBox::Cancel);
        dialog.button(QMessageBox::Ok)->setText(tr("Write"));
        if (dialog.exec() == QMessageBox::Ok)
            statusBar()->showMessage(tr("Flashing is not implemented in this preview"), 4000);
    }

    QVector<Board> boards_;
    QString sourcePath_;
    QString outputPath_;
    QString selectedBoard_;
    QString selectedPlatform_;
    QRadioButton *rootfsButton_ = nullptr;
    QRadioButton *imageButton_ = nullptr;
    QRadioButton *driveOutputButton_ = nullptr;
    QRadioButton *fileOutputButton_ = nullptr;
    QLabel *sourceLabel_ = nullptr;
    QLabel *sourceHint_ = nullptr;
    QLabel *boardLabel_ = nullptr;
    QLabel *boardHint_ = nullptr;
    QLabel *outputLabel_ = nullptr;
    QWidget *driveRow_ = nullptr;
    QWidget *fileRow_ = nullptr;
    QComboBox *driveBox_ = nullptr;
    QPushButton *writeButton_ = nullptr;
};

} // namespace

extern "C" int run_qt_app(int argc, char **argv, const char *boards, const char *drives) {
    QApplication app(argc, argv);
    QCoreApplication::setApplicationName(QStringLiteral("ALT Image Writer"));
    QCoreApplication::setOrganizationName(QStringLiteral("ALT Linux"));
    QApplication::setWindowIcon(QApplication::style()->standardIcon(QStyle::SP_DriveHDIcon));
    MainWindow window(QString::fromUtf8(boards), QString::fromUtf8(drives));
    window.show();
    return app.exec();
}