#include "DesktopIconProvider.hpp"

#include <QCoreApplication>
#include <QDir>
#include <QGuiApplication>
#include <QIcon>
#include <QQmlApplicationEngine>
#include <QQuickWindow>
#include <QUrl>
#include <QtGlobal>

#if QT_VERSION < QT_VERSION_CHECK(6, 5, 0)
#include <LayerShellQt/Shell>
#endif

namespace {

void initializeIconTheme()
{
    if (QIcon::themeName().isEmpty()) {
        const QStringList candidates = {
            QStringLiteral("Adwaita"),
            QStringLiteral("Yaru"),
            QStringLiteral("ubuntu-mono-dark"),
            QStringLiteral("breeze"),
            QStringLiteral("hicolor"),
        };

        const QStringList searchPaths = QIcon::themeSearchPaths();
        for (const QString &theme : candidates) {
            for (const QString &root : searchPaths) {
                if (QDir(root + QLatin1Char('/') + theme).exists()) {
                    QIcon::setThemeName(theme);
                    break;
                }
            }
            if (!QIcon::themeName().isEmpty())
                break;
        }
    }

    if (QIcon::fallbackThemeName().isEmpty())
        QIcon::setFallbackThemeName(QStringLiteral("hicolor"));
}

} // namespace

int main(int argc, char *argv[])
{
#if QT_VERSION < QT_VERSION_CHECK(6, 5, 0)
    LayerShellQt::Shell::useLayerShell();
#endif

    QGuiApplication app(argc, argv);
    app.setApplicationName(QStringLiteral("nebula-shell"));
    app.setApplicationDisplayName(QStringLiteral("Nebula Desktop"));
    app.setOrganizationName(QStringLiteral("NebulaOS"));
    app.setDesktopFileName(QStringLiteral("org.nebulaos.shell"));

    initializeIconTheme();
    QQuickWindow::setDefaultAlphaBuffer(true);

    QQmlApplicationEngine engine;
    engine.addImportPath(QStringLiteral("qrc:/qt/qml"));
    engine.addImageProvider(QStringLiteral("desktopicon"), new DesktopIconProvider);

    QObject::connect(
        &engine,
        &QQmlApplicationEngine::objectCreationFailed,
        &app,
        []() {
            qCritical("nebula-shell: failed to load the Nebula QML module.");
            QCoreApplication::exit(EXIT_FAILURE);
        },
        Qt::QueuedConnection);

#if QT_VERSION >= QT_VERSION_CHECK(6, 5, 0)
    engine.loadFromModule(QStringLiteral("Nebula.Shell"), QStringLiteral("Main"));
#else
    engine.load(QUrl(QStringLiteral("qrc:/qt/qml/Nebula/Shell/Main.qml")));
#endif

    if (engine.rootObjects().isEmpty()) {
        qCritical("nebula-shell: failed to load the Nebula QML module.");
        return EXIT_FAILURE;
    }

    return app.exec();
}