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#include "generalsettings.h"
#include "coreconstants.h"
#include "coreplugintr.h"
#include "icore.h"
#include "themechooser.h"

#include <coreplugin/dialogs/restartdialog.h>

#include <utils/algorithm.h>
#include <utils/checkablemessagebox.h>
#include <utils/hostosinfo.h>
#include <utils/infobar.h>
#include <utils/layoutbuilder.h>
#include <utils/qtcolorbutton.h>
#include <utils/stylehelper.h>

#include <QCheckBox>
#include <QComboBox>
#include <QCoreApplication>
#include <QDir>
#include <QGuiApplication>
#include <QLibraryInfo>
#include <QMessageBox>
#include <QPushButton>
#include <QSettings>
#include <QStyleHints>
#include <QTextCodec>

using namespace Utils;
using namespace Layouting;

namespace Core {
namespace Internal {

const char settingsKeyDPI[] = "Core/EnableHighDpiScaling";
const char settingsKeyShortcutsInContextMenu[] = "General/ShowShortcutsInContextMenu";
const char settingsKeyCodecForLocale[] = "General/OverrideCodecForLocale";

class GeneralSettingsWidget final : public IOptionsPageWidget
{
    Q_DECLARE_TR_FUNCTIONS(Core::Internal::GeneralSettings)
public:
    explicit GeneralSettingsWidget(GeneralSettings *q);

    void apply() final;

    void resetInterfaceColor();
    void resetWarnings();
    void resetLanguage();

    static bool canResetWarnings();
    void fillLanguageBox() const;
    static QString language();
    static void setLanguage(const QString&);
    void fillCodecBox() const;
    static QByteArray codecForLocale();
    static void setCodecForLocale(const QByteArray&);

    GeneralSettings *q;
    QComboBox *m_languageBox;
    QComboBox *m_codecBox;
    QCheckBox *m_showShortcutsInContextMenus;
    QtColorButton *m_colorButton;
    ThemeChooser *m_themeChooser;
    QPushButton *m_resetWarningsButton;
};

GeneralSettingsWidget::GeneralSettingsWidget(GeneralSettings *q)
    : q(q)
    , m_languageBox(new QComboBox)
    , m_codecBox(new QComboBox)
    , m_showShortcutsInContextMenus(new QCheckBox)
    , m_colorButton(new QtColorButton)
    , m_themeChooser(new ThemeChooser)
    , m_resetWarningsButton(new QPushButton)
{
    m_languageBox->setSizeAdjustPolicy(QComboBox::AdjustToMinimumContentsLengthWithIcon);
    m_languageBox->setMinimumContentsLength(20);

    m_codecBox->setSizeAdjustPolicy(QComboBox::AdjustToMinimumContentsLengthWithIcon);
    m_codecBox->setMinimumContentsLength(20);

    m_colorButton->setMinimumSize(QSize(64, 0));
    m_colorButton->setProperty("alphaAllowed", QVariant(false));

    m_resetWarningsButton->setText(tr("Reset Warnings", "Button text"));
    m_resetWarningsButton->setToolTip(
        tr("Re-enable warnings that were suppressed by selecting \"Do Not "
           "Show Again\" (for example, missing highlighter).",
           nullptr));

    auto resetColorButton = new QPushButton(tr("Reset"));
    resetColorButton->setToolTip(tr("Reset to default.", "Color"));

    Form form;
    form.addRow({tr("Color:"), m_colorButton, resetColorButton, st});
    form.addRow({tr("Theme:"), m_themeChooser});
    form.addRow({tr("Language:"), m_languageBox, st});

    if (!Utils::HostOsInfo::isMacHost()) {
        auto dpiCheckbox = new QCheckBox(tr("Enable high DPI scaling"));
        form.addRow({empty, dpiCheckbox});
        const bool defaultValue = Utils::HostOsInfo::isWindowsHost();
        dpiCheckbox->setChecked(ICore::settings()->value(settingsKeyDPI, defaultValue).toBool());
        connect(dpiCheckbox, &QCheckBox::toggled, this, [defaultValue](bool checked) {
            ICore::settings()->setValueWithDefault(settingsKeyDPI, checked, defaultValue);
            QMessageBox::information(ICore::dialogParent(),
                                     tr("Restart Required"),
                                     tr("The high DPI settings will take effect after restart."));
        });
    }

    form.addRow({empty, m_showShortcutsInContextMenus});
    form.addRow(Row{m_resetWarningsButton, st});
    form.addRow({tr("Text codec for tools:"), m_codecBox, st});
    Column{Group{Title(tr("User Interface")), form}}.attachTo(this);

    fillLanguageBox();
    fillCodecBox();

    m_colorButton->setColor(StyleHelper::requestedBaseColor());
    m_resetWarningsButton->setEnabled(canResetWarnings());

    m_showShortcutsInContextMenus->setText(
        tr("Show keyboard shortcuts in context menus (default: %1)")
            .arg(q->m_defaultShowShortcutsInContextMenu ? Tr::tr("on") : Tr::tr("off")));
    m_showShortcutsInContextMenus->setChecked(GeneralSettings::showShortcutsInContextMenu());

    connect(resetColorButton,
            &QAbstractButton::clicked,
            this,
            &GeneralSettingsWidget::resetInterfaceColor);
    connect(m_resetWarningsButton,
            &QAbstractButton::clicked,
            this,
            &GeneralSettingsWidget::resetWarnings);
}

static bool hasQmFilesForLocale(const QString &locale, const QString &creatorTrPath)
{
    static const QString qtTrPath = QLibraryInfo::location(QLibraryInfo::TranslationsPath);

    const QString trFile = QLatin1String("/qt_") + locale + QLatin1String(".qm");
    return QFile::exists(qtTrPath + trFile) || QFile::exists(creatorTrPath + trFile);
}

void GeneralSettingsWidget::fillLanguageBox() const
{
    const QString currentLocale = language();

    m_languageBox->addItem(tr("<System Language>"), QString());
    // need to add this explicitly, since there is no qm file for English
    m_languageBox->addItem(QLatin1String("English"), QLatin1String("C"));
    if (currentLocale == QLatin1String("C"))
        m_languageBox->setCurrentIndex(m_languageBox->count() - 1);

    const FilePath creatorTrPath = ICore::resourcePath("translations");
    const QStringList languageFiles = creatorTrPath.toDir().entryList(
        QStringList(QLatin1String("qtcreator*.qm")));

    for (const QString &languageFile : languageFiles) {
        int start = languageFile.indexOf('_') + 1;
        int end = languageFile.lastIndexOf('.');
        const QString locale = languageFile.mid(start, end-start);
        // no need to show a language that creator will not load anyway
        if (hasQmFilesForLocale(locale, creatorTrPath.toString())) {
            QLocale tmpLocale(locale);
            QString languageItem = QLocale::languageToString(tmpLocale.language()) + QLatin1String(" (")
                                   + QLocale::countryToString(tmpLocale.country()) + QLatin1Char(')');
            m_languageBox->addItem(languageItem, locale);
            if (locale == currentLocale)
                m_languageBox->setCurrentIndex(m_languageBox->count() - 1);
        }
    }
}

void GeneralSettingsWidget::apply()
{
    int currentIndex = m_languageBox->currentIndex();
    setLanguage(m_languageBox->itemData(currentIndex, Qt::UserRole).toString());
    currentIndex = m_codecBox->currentIndex();
    setCodecForLocale(m_codecBox->itemText(currentIndex).toLocal8Bit());
    q->setShowShortcutsInContextMenu(m_showShortcutsInContextMenus->isChecked());
    // Apply the new base color if accepted
    StyleHelper::setBaseColor(m_colorButton->color());
    m_themeChooser->apply();
}

bool GeneralSettings::showShortcutsInContextMenu()
{
    return ICore::settings()
        ->value(settingsKeyShortcutsInContextMenu,
                QGuiApplication::styleHints()->showShortcutsInContextMenus())
        .toBool();
}

void GeneralSettingsWidget::resetInterfaceColor()
{
    m_colorButton->setColor(StyleHelper::DEFAULT_BASE_COLOR);
}

void GeneralSettingsWidget::resetWarnings()
{
    InfoBar::clearGloballySuppressed();
    CheckableMessageBox::resetAllDoNotAskAgainQuestions(ICore::settings());
    m_resetWarningsButton->setEnabled(false);
}

bool GeneralSettingsWidget::canResetWarnings()
{
    return InfoBar::anyGloballySuppressed()
        || CheckableMessageBox::hasSuppressedQuestions(ICore::settings());
}

void GeneralSettingsWidget::resetLanguage()
{
    // system language is default
    m_languageBox->setCurrentIndex(0);
}

QString GeneralSettingsWidget::language()
{
    QSettings *settings = ICore::settings();
    return settings->value(QLatin1String("General/OverrideLanguage")).toString();
}

void GeneralSettingsWidget::setLanguage(const QString &locale)
{
    QtcSettings *settings = ICore::settings();
    if (settings->value(QLatin1String("General/OverrideLanguage")).toString() != locale) {
        RestartDialog dialog(ICore::dialogParent(),
                             tr("The language change will take effect after restart."));
        dialog.exec();
    }

    settings->setValueWithDefault(QLatin1String("General/OverrideLanguage"), locale, {});
}

void GeneralSettingsWidget::fillCodecBox() const
{
    const QByteArray currentCodec = codecForLocale();

    QByteArrayList codecs = QTextCodec::availableCodecs();
    Utils::sort(codecs);
    for (const QByteArray &codec : qAsConst(codecs)) {
        m_codecBox->addItem(QString::fromLocal8Bit(codec));
        if (codec == currentCodec)
            m_codecBox->setCurrentIndex(m_codecBox->count() - 1);
    }
}

QByteArray GeneralSettingsWidget::codecForLocale()
{
    QSettings *settings = ICore::settings();
    QByteArray codec = settings->value(settingsKeyCodecForLocale).toByteArray();
    if (codec.isEmpty())
        codec = QTextCodec::codecForLocale()->name();
    return codec;
}

void GeneralSettingsWidget::setCodecForLocale(const QByteArray &codec)
{
    QtcSettings *settings = ICore::settings();
    settings->setValueWithDefault(settingsKeyCodecForLocale, codec, {});
    QTextCodec::setCodecForLocale(QTextCodec::codecForName(codec));
}

void GeneralSettings::setShowShortcutsInContextMenu(bool show)
{
    ICore::settings()->setValueWithDefault(settingsKeyShortcutsInContextMenu,
                                           show,
                                           m_defaultShowShortcutsInContextMenu);
    QGuiApplication::styleHints()->setShowShortcutsInContextMenus(show);
}

GeneralSettings::GeneralSettings()
{
    setId(Constants::SETTINGS_ID_INTERFACE);
    setDisplayName(GeneralSettingsWidget::tr("Interface"));
    setCategory(Constants::SETTINGS_CATEGORY_CORE);
    setDisplayCategory(Tr::tr("Environment"));
    setCategoryIconPath(":/core/images/settingscategory_core.png");
    setWidgetCreator([this] { return new GeneralSettingsWidget(this); });

    m_defaultShowShortcutsInContextMenu = QGuiApplication::styleHints()
                                              ->showShortcutsInContextMenus();
}

} // namespace Internal
} // namespace Core