/*
    SPDX-FileCopyrightText: 2019 Harald Sitter <sitter@kde.org>

    SPDX-License-Identifier: GPL-2.0-only OR GPL-3.0-only OR LicenseRef-KDE-Accepted-GPL
*/

#include <QCommandLineParser>
#include <QDebug>
#include <QProcess>
#include <QQmlApplicationEngine>
#include <QQmlContext>
#include <QtGui/private/qtx11extras_p.h>

#include <KAboutData>
#include <KLocalizedString>

#include <memory>

#include "application.h"
#include "config-workspace.h"
#include "doodad.h"
#include "geometry.h"

// kind-of copy from xkb_rules.cpp (less complicated)
static QString getRulesName()
{
    XkbRF_VarDefsRec vd;
    char *tmp = nullptr;

    if (XkbRF_GetNamesProp(QX11Info::display(), &tmp, &vd) && tmp != nullptr) {
        const QString name(tmp);
        XFree(tmp);
        return name;
    }

    return QStringLiteral("evdev"); // default to evdev
}

static QString findXkbRulesFile()
{
    const QString rulesName = getRulesName();
    return QStringLiteral("%1/rules/%2").arg(XKBDIR, rulesName);
}

int main(int argc, char *argv[])
{
    setenv("QT_QPA_PLATFORM", "xcb", 1);
    Application app(argc, argv);
    Q_ASSERT(app.platformName() == QStringLiteral("xcb"));

    KAboutData aboutData(QStringLiteral("tastenbrett"),
                         i18nc("app display name", "Keyboard Preview"),
                         QStringLiteral("1.0"),
                         i18nc("app description", "Keyboard layout visualization"),
                         KAboutLicense::GPL);
    KAboutData::setApplicationData(aboutData);

    QCommandLineParser parser;
    aboutData.setupCommandLine(&parser);

    QCommandLineOption modelOption(QStringList{"m", "model"}, {}, QStringLiteral("MODEL"));
    parser.addOption(modelOption);
    QCommandLineOption layoutOption(QStringList{"l", "layout"}, {}, QStringLiteral("LAYOUT"));
    parser.addOption(layoutOption);
    QCommandLineOption variantOption(QStringList{"a", "variant"}, {}, QStringLiteral("VARIANT"));
    parser.addOption(variantOption);
    QCommandLineOption optionsOption(QStringList{"o", "options"}, {}, QStringLiteral("OPTIONS"));
    parser.addOption(optionsOption);
    parser.process(app);
    aboutData.processCommandLine(&parser);

    XkbRF_VarDefsRec varDefs;
    memset(&varDefs, 0, sizeof(XkbRF_VarDefsRec));

    // Models worth testing for obvious mistakes:
    // pc104, tm2020 (fancy), kinesis (fancy)
    QString model = parser.value(modelOption);
    const QString layout = parser.value(layoutOption);
    const QString variant = parser.value(variantOption);
    const QString options = parser.value(optionsOption);

    // Hold these so so we can pass data into xkb getter.
    QByteArray modelArray = model.toUtf8();
    QByteArray layoutArray = layout.toUtf8();
    QByteArray variantArray = variant.toUtf8();
    QByteArray optionsArray = options.toUtf8();

    varDefs.model = modelArray.data();
    varDefs.layout = layoutArray.data();
    varDefs.variant = variantArray.data();
    varDefs.options = optionsArray.data();

    XkbRF_RulesPtr rules = XkbRF_Load(findXkbRulesFile().toUtf8().data(), // needs to be non-const!
                                      qgetenv("LOCALE").data(),
                                      True,
                                      True);

    Q_ASSERT(rules);
    std::unique_ptr<XkbRF_RulesRec, std::function<void(XkbRF_RulesPtr)>> rulesCleanup(rules, [](XkbRF_RulesPtr obj) {
        XkbRF_Free(obj, True);
    });

    XkbComponentNamesRec componentNames;
    memset(&componentNames, 0, sizeof(XkbComponentNamesRec));
    XkbRF_GetComponents(rules, &varDefs, &componentNames);

    QString errorDescription;
    QString errorDetails;
    std::unique_ptr<Geometry> geometry;

    XkbDescPtr xkb =
        XkbGetKeyboardByName(QX11Info::display(),
                             XkbUseCoreKbd,
                             &componentNames,
                             0,
                             XkbGBN_GeometryMask | XkbGBN_KeyNamesMask | XkbGBN_OtherNamesMask | XkbGBN_ClientSymbolsMask | XkbGBN_IndicatorMapMask,
                             false);
    if (!xkb) {
        QProcess setxkbmap;
        QProcess xkbcomp;

        setxkbmap.setStandardOutputProcess(&xkbcomp);
        xkbcomp.setProcessChannelMode(QProcess::MergedChannels); // combine in single channel
        setxkbmap.start(QStringLiteral("setxkbmap"),
                        {QStringLiteral("-print"),
                         QStringLiteral("-model"),
                         model,
                         QStringLiteral("-layout"),
                         layout,
                         QStringLiteral("-variant"),
                         variant,
                         QStringLiteral("-option"),
                         options});
        xkbcomp.start(QStringLiteral("xkbcomp"), {QStringLiteral("-")});
        setxkbmap.waitForFinished();
        xkbcomp.waitForFinished();

        errorDescription = i18nc("@label",
                                 "The keyboard geometry failed to load."
                                 " This often indicates that the selected model does not support a specific layout"
                                 " or layout variant."
                                 " This problem will likely also present when you try to use this combination of model, layout and variant."
                                 "\nPreviewing layouts that are defined outside your systems xkb directory is not supported and "
                                 " will also trigger this message. These might still work fine if applied");
        errorDetails = xkbcomp.readAllStandardOutput();
    } else {
        Q_ASSERT(xkb);
        geometry.reset(new Geometry(xkb->geom, xkb));
    }

    // Register the doodads so we can perform easy type checks with them
    // and determine how to render the individual object.
    const char uri[] = "org.kde.tastenbrett.private";
    qmlRegisterUncreatableType<TextDoodad>(uri, 1, 0, "TextDoodad", QString());
    qmlRegisterUncreatableType<LogoDoodad>(uri, 1, 0, "LogoDoodad", QString());
    qmlRegisterUncreatableType<ShapeDoodad>(uri, 1, 0, "ShapeDoodad", QString());
    qmlRegisterUncreatableType<IndicatorDoodad>(uri, 1, 0, "IndicatorDoodad", QString());

    // The way this is currently written we need the engine after
    // we have a geometry, lest geometry is dtor'd before the engine
    // causing exhaustive error spam on shutdown.
    // Also, the above stuff is blocking, but optimizing it is hardly
    // worth the effort. The Xkb calls altogether take ~8ms (I am not
    // certain putting xkb into a qfuture is thread-safe or even
    // faster). Constructing our QObjects takes 1ms.
    QQmlApplicationEngine engine;
    const QUrl url(QStringLiteral("qrc:/qml/main.qml"));
    QObject::connect(
        &engine,
        &QQmlApplicationEngine::objectCreated,
        &app,
        [url](QObject *obj, const QUrl &objUrl) {
            if (!obj && url == objUrl)
                QCoreApplication::exit(-1);
        },
        Qt::QueuedConnection);
    engine.rootContext()->setContextProperty("geometry", geometry.get());
    engine.rootContext()->setContextProperty("errorDescription", errorDescription);
    engine.rootContext()->setContextProperty("errorDetails", errorDetails);
    engine.load(url);

    return app.exec();
}

#include "main.moc"