#include "RaveWelcomeViewStep.h"

#include "RaveBillentyuzet.h"

#include <QButtonGroup>
#include <QFrame>
#include <QGridLayout>
#include <QHBoxLayout>
#include <QLabel>
#include <QLocale>
#include <QPainter>
#include <QProcess>
#include <QPixmap>
#include <QPushButton>
#include <QVBoxLayout>

#include <Branding.h>
#include <GlobalStorage.h>
#include <JobQueue.h>
#include <ViewManager.h>
#include <locale/Translation.h>
#include <utils/Retranslator.h>

CALAMARES_PLUGIN_FACTORY_DEFINITION(RaveWelcomeViewStepFactory, registerPlugin<RaveWelcomeViewStep>();)

namespace
{
struct LanguageTexts
{
    QString title;
    QString next;
    QString installer;
};

LanguageTexts textsFor(const QString& localeId)
{
    if (localeId.startsWith(QLatin1String("hu")))
        return { QStringLiteral("VÁLASSZ NYELVET"), QStringLiteral("Tovább"), QStringLiteral("TELEPÍTŐ") };
    if (localeId.startsWith(QLatin1String("de")))
        return { QStringLiteral("SPRACHE WÄHLEN"), QStringLiteral("Weiter"), QStringLiteral("INSTALLATION") };
    return { QStringLiteral("CHOOSE YOUR LANGUAGE"), QStringLiteral("Next"), QStringLiteral("INSTALLER") };
}

QString fullLocaleName(const QString& localeId)
{
    QString lang = QLocale(localeId).name();
    if (lang.isEmpty())
        lang = localeId;
    return lang.contains('.') ? lang : lang + ".UTF-8";
}

QString nativeName(const QString& localeId)
{
    QString name = QLocale(localeId).nativeLanguageName();
    if (name.isEmpty())
        return localeId;
    name[0] = name[0].toUpper();
    return name;
}
}

class BgWidget : public QWidget
{
public:
    explicit BgWidget(QWidget* parent = nullptr) : QWidget(parent) {}

    void setPixmap(const QPixmap& px) { m_pixmap = px; update(); }

protected:
    void paintEvent(QPaintEvent*) override
    {
        QPainter p(this);
        p.fillRect(rect(), QColor(0x1a, 0x1b, 0x1d));
        if (m_pixmap.isNull()) return;
        const QSize scaled = m_pixmap.size().scaled(size(), Qt::KeepAspectRatioByExpanding);
        const QRect target((width() - scaled.width()) / 2,
                           (height() - scaled.height()) * 4 / 10,
                           scaled.width(),
                           scaled.height());
        p.setRenderHint(QPainter::SmoothPixmapTransform);
        p.drawPixmap(target, m_pixmap);
    }

private:
    QPixmap m_pixmap;
};

RaveWelcomeViewStep::RaveWelcomeViewStep(QObject* parent)
    : Calamares::ViewStep(parent)
{
    RaveBillentyuzet::regisztral();
    m_localeIds = { "hu", "en", "en_GB", "de" };
}

RaveWelcomeViewStep::~RaveWelcomeViewStep()
{
    if (m_widget && m_widget->parent() == nullptr)
        delete m_widget;
}

QString RaveWelcomeViewStep::prettyName() const
{
    const QString locale = getLocale();
    if (locale.startsWith("hu"))
    {
        return QStringLiteral("Nyelv");
    }
    if (locale.startsWith("de"))
    {
        return QStringLiteral("Sprache");
    }
    return tr("Language");
}

QString RaveWelcomeViewStep::getLocale() const
{
    if (Calamares::JobQueue::instance())
    {
        Calamares::GlobalStorage* gs = Calamares::JobQueue::instance()->globalStorage();
        if (gs)
        {
            if (gs->contains("locale"))
            {
                const QString loc = gs->value("locale").toString();
                if (!loc.isEmpty())
                    return loc;
            }

            if (gs->contains("localeConf"))
            {
                const QString loc = gs->value("localeConf").toMap().value("LANG").toString();
                if (!loc.isEmpty())
                    return loc;
            }
        }
    }

    return QLocale::system().name();
}

void RaveWelcomeViewStep::buildWidget()
{
    auto* bg = new BgWidget();
    bg->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Expanding);

    QString imgPath;
    if (Calamares::Branding::instance())
        imgPath = Calamares::Branding::instance()->imagePath(Calamares::Branding::ProductWelcome);

    if (!imgPath.isEmpty())
        bg->setPixmap(QPixmap(imgPath));

    m_tag = new QLabel();
    m_tag->setObjectName("ravewelcomeTag");

    auto* panel = new QFrame();
    panel->setObjectName("ravewelcomeBar");

    m_title = new QLabel();
    m_title->setObjectName("ravewelcomeTitle");
    m_localeLabel = new QLabel();
    m_localeLabel->setObjectName("ravewelcomeLocale");

    auto* headerLayout = new QHBoxLayout();
    headerLayout->setContentsMargins(0, 0, 0, 0);
    headerLayout->addWidget(m_title);
    headerLayout->addStretch();
    headerLayout->addWidget(m_localeLabel, 0, Qt::AlignBottom);

    m_langButtons = new QButtonGroup(panel);
    m_langButtons->setExclusive(true);
    auto* langLayout = new QGridLayout();
    langLayout->setContentsMargins(0, 0, 0, 0);
    langLayout->setHorizontalSpacing(8);
    for (int i = 0; i < m_localeIds.size(); ++i)
    {
        auto* button = new QPushButton(nativeName(m_localeIds[i]));
        button->setObjectName("ravewelcomeLang");
        button->setCheckable(true);
        button->setMinimumHeight(48);
        button->setSizePolicy(QSizePolicy::Expanding, QSizePolicy::Fixed);
        m_langButtons->addButton(button, i);
        langLayout->addWidget(button, 0, i);
    }

    m_next = new QPushButton();
    m_next->setObjectName("ravewelcomeNext");
    m_next->setMinimumHeight(48);
    connect(m_next, &QPushButton::clicked, this, []()
    {
        if (auto* vm = Calamares::ViewManager::instance())
            vm->next();
    });

    auto* actionLayout = new QHBoxLayout();
    actionLayout->setContentsMargins(0, 0, 0, 0);
    actionLayout->setSpacing(12);
    actionLayout->addLayout(langLayout, 1);
    actionLayout->addWidget(m_next);

    auto* panelLayout = new QVBoxLayout(panel);
    panelLayout->setContentsMargins(24, 20, 24, 20);
    panelLayout->setSpacing(14);
    panelLayout->addLayout(headerLayout);
    panelLayout->addLayout(actionLayout);

    const QString sysName = QLocale::system().name();
    int exact = -1;
    int prefix = -1;
    for (int i = 0; i < m_localeIds.size(); ++i)
    {
        if (m_localeIds[i] == sysName)
            exact = i;
        else if (prefix < 0 && sysName.startsWith(m_localeIds[i].left(2)))
            prefix = i;
    }
    if (exact >= 0)
        m_currentLocaleIndex = exact;
    else if (prefix >= 0)
        m_currentLocaleIndex = prefix;
    else
        m_currentLocaleIndex = qMax(0, m_localeIds.indexOf("en"));

    if (auto* button = m_langButtons->button(m_currentLocaleIndex))
        button->setChecked(true);

    applyLiveKeyboardLayout(m_localeIds.value(m_currentLocaleIndex));

    connect(m_langButtons, &QButtonGroup::idClicked,
            this, &RaveWelcomeViewStep::onLanguageChanged);

    auto* mainLayout = new QVBoxLayout(bg);
    mainLayout->setSpacing(0);
    mainLayout->addWidget(m_tag, 0, Qt::AlignLeft | Qt::AlignTop);
    mainLayout->addStretch();
    mainLayout->addWidget(panel);

    m_widget = bg;
    updateTexts();
}

void RaveWelcomeViewStep::updateTexts()
{
    const QString localeId = m_localeIds.value(m_currentLocaleIndex);
    const LanguageTexts texts = textsFor(localeId);

    QString version;
    if (Calamares::Branding::instance())
        version = Calamares::Branding::instance()->string(Calamares::Branding::Version);
    const QString product = version.isEmpty() ? QStringLiteral("RAVEOS") : QStringLiteral("RAVEOS ") + version;

    m_tag->setText(product + QStringLiteral(" · ") + texts.installer);
    m_title->setText(texts.title);
    m_localeLabel->setText(fullLocaleName(localeId));
    m_next->setText(texts.next);
}

QSize RaveWelcomeViewStep::widgetMargins(Qt::Orientations)
{
    return QSize(28, 24);
}

QWidget* RaveWelcomeViewStep::widget()
{
    if (!m_widget)
        buildWidget();
    return m_widget;
}

void RaveWelcomeViewStep::onLanguageChanged(int index)
{
    if (index < 0 || index >= m_localeIds.size())
        return;

    m_currentLocaleIndex = index;
    QString localeId = m_localeIds[index];

    if (Calamares::JobQueue::instance())
    {
        Calamares::GlobalStorage* gs = Calamares::JobQueue::instance()->globalStorage();
        if (gs)
        {
            QString lang = QLocale(localeId).name();
            if (lang.isEmpty())
                lang = localeId;
            const QString fullLocale = fullLocaleName(localeId);

            const char* lcKeys[] = {
                "LANG", "LC_NUMERIC", "LC_TIME", "LC_MONETARY", "LC_PAPER",
                "LC_NAME", "LC_ADDRESS", "LC_TELEPHONE", "LC_MEASUREMENT",
                "LC_IDENTIFICATION"
            };
            QVariantMap localeConf = gs->value("localeConf").toMap();
            for (const char* k : lcKeys)
                localeConf.insert(QLatin1String(k), fullLocale);
            gs->insert("localeConf", localeConf);

            gs->insert("locale", lang);
        }
    }

    Calamares::Locale::Translation::Id tid { localeId };
    Calamares::installTranslator(tid, brandingTranslationsPrefix());

    applyLiveKeyboardLayout(localeId);
    updateTexts();
}

QString RaveWelcomeViewStep::brandingTranslationsPrefix() const
{
    if (Calamares::Branding::instance())
        return Calamares::Branding::instance()->translationsDirectory();
    return QString();
}

void RaveWelcomeViewStep::applyLiveKeyboardLayout(const QString& localeId)
{
    QString layout = QStringLiteral("us");
    if (localeId.startsWith(QLatin1String("hu")))
    {
        layout = QStringLiteral("hu");
    }
    else if (localeId.startsWith(QLatin1String("de")))
    {
        layout = QStringLiteral("de");
    }
    else if (localeId == QLatin1String("en_GB"))
    {
        layout = QStringLiteral("gb");
    }

    const QStringList args { QStringLiteral("-layout"), layout };
    QProcess::startDetached(QStringLiteral("setxkbmap"), args);
}

bool RaveWelcomeViewStep::isNextEnabled() const { return true; }
bool RaveWelcomeViewStep::isBackEnabled() const { return false; }
bool RaveWelcomeViewStep::isAtBeginning() const { return true; }
bool RaveWelcomeViewStep::isAtEnd() const { return true; }

Calamares::JobList RaveWelcomeViewStep::jobs() const { return {}; }

void RaveWelcomeViewStep::setConfigurationMap(const QVariantMap& config)
{
    if (config.contains("languages"))
    {
        QStringList langs;
        for (const auto& v : config.value("languages").toList())
            langs << v.toString();
        if (!langs.isEmpty())
            m_localeIds = langs;
    }
}