/******************************************************************************
 * QSkinny - Copyright (C) 2016 Uwe Rathmann
 *           SPDX-License-Identifier: BSD-3-Clause
 *****************************************************************************/

#include <SkinnyShortcut.h>

#include <QskDialog.h>
#include <QskFocusIndicator.h>
#include <QskInputContext.h>
#include <QskInputPanel.h>
#include <QskLinearBox.h>
#include <QskListView.h>
#include <QskTextInput.h>

#include <QskAspect.h>
#include <QskFunctions.h>
#include <QskInputPanelBox.h>
#include <QskObjectCounter.h>
#include <QskVirtualKeyboard.h>
#include <QskWindow.h>

#include <QFontMetricsF>
#include <QGuiApplication>

namespace
{
    class Keyboard final : public QskVirtualKeyboard
    {
        using Inherited = QskVirtualKeyboard;

        public:
            Keyboard( QQuickItem* parentItem = nullptr ):
                QskVirtualKeyboard( parentItem )
            {
                // here rearrange keyboard layouts if necessary
            }
    };

    class Panel : public QskInputPanel
    {
        public:
        Panel( QQuickItem* parentItem = nullptr )
            : QskInputPanel( parentItem )
        {
            setAutoLayoutChildren( true );
            setLayoutAlignmentHint( Qt::AlignHCenter | Qt::AlignBottom );

            m_box = new QskInputPanelBox( this );
            m_box->setKeyboard( new Keyboard() );

            connect( m_box, &QskInputPanelBox::keySelected,
                this, &QskInputPanel::keySelected );

            connect( m_box, &QskInputPanelBox::predictiveTextSelected,
                this, &QskInputPanel::predictiveTextSelected );
        }

        void attachItem( QQuickItem* item ) override
        {
            m_box->attachInputItem( item );
        }

        QQuickItem* inputProxy() const override
        {
            return m_box->inputProxy();
        }

        void setPrompt( const QString& prompt ) override
        {
            m_box->setInputPrompt( prompt );
        }

        void setPredictionEnabled( bool on ) override
        {
            m_box->setPanelHint( QskInputPanelBox::Prediction, on );
        }

        void setPrediction( const QStringList& prediction ) override
        {
            QskInputPanel::setPrediction( prediction );
            m_box->setPrediction( prediction );
        }


      private:
        QskInputPanelBox* m_box;
    };

    class InputContextFactory : public QskInputContextFactory
    {
        QskInputPanel* createPanel() const override
        {
            return new Panel;
        }
    };

    QString nativeLocaleString( const QLocale& locale )
    {
        switch ( locale.language() )
        {
            case QLocale::Bulgarian:
                return QStringLiteral( "български език" );

            case QLocale::Czech:
                return QStringLiteral( "Čeština" );

            case QLocale::German:
                return QStringLiteral( "Deutsch" );

            case QLocale::Danish:
                return QStringLiteral( "Dansk" );

            case QLocale::Greek:
                return QStringLiteral( "Eλληνικά" );

            case QLocale::English:
            {
                const auto territory =
#if QT_VERSION >= QT_VERSION_CHECK( 6, 2, 0 )
                    locale.territory();
#else
                    locale.country();
#endif

                switch ( territory )
                {
                    case QLocale::Canada:
                    case QLocale::UnitedStates:
                    case QLocale::UnitedStatesMinorOutlyingIslands:
                    case QLocale::UnitedStatesVirginIslands:
                        return QStringLiteral( "English (US)" );

                    default:
                        return QStringLiteral( "English (UK)" );
                }
            }

            case QLocale::Spanish:
                return QStringLiteral( "Español" );

            case QLocale::Finnish:
                return QStringLiteral( "Suomi" );

            case QLocale::French:
                return QStringLiteral( "Français" );

            case QLocale::Hungarian:
                return QStringLiteral( "Magyar" );

            case QLocale::Italian:
                return QStringLiteral( "Italiano" );

            case QLocale::Japanese:
                return QStringLiteral( "日本語" );

            case QLocale::Latvian:
                return QStringLiteral( "Latviešu" );

            case QLocale::Lithuanian:
                return QStringLiteral( "Lietuvių" );

            case QLocale::Dutch:
                return QStringLiteral( "Nederlands" );

            case QLocale::Portuguese:
                return QStringLiteral( "Português" );

            case QLocale::Romanian:
                return QStringLiteral( "Română" );

            case QLocale::Russian:
                return QStringLiteral( "Русский" );

            case QLocale::Slovenian:
                return QStringLiteral( "Slovenščina" );

            case QLocale::Slovak:
                return QStringLiteral( "Slovenčina" );

            case QLocale::Turkish:
                return QStringLiteral( "Türkçe" );

            case QLocale::Chinese:
                return QStringLiteral( "中文" );

            default:
                return QLocale::languageToString( locale.language() );
        }
    }
}

class InputBox : public QskLinearBox
{
  public:
    InputBox( QQuickItem* parentItem = nullptr )
        : QskLinearBox( Qt::Vertical, parentItem )
    {
        setExtraSpacingAt( Qt::BottomEdge | Qt::RightEdge );

        setMargins( 10 );
        setSpacing( 10 );

        auto* textInput1 = new QskTextInput( this );
        textInput1->setText( "Press and edit Me." );
        textInput1->setSizePolicy( Qt::Horizontal, QskSizePolicy::Preferred );

        auto* textInput2 = new QskTextInput( this );
        textInput2->setText( "Press and edit Me." );
        textInput2->setSizePolicy( Qt::Horizontal, QskSizePolicy::Preferred );
        textInput2->setActivationModes( QskTextInput::ActivationOnAll );

        auto* textInput3 = new QskTextInput( this );
        textInput3->setReadOnly( true );
        textInput3->setText( "Read Only information." );
        textInput3->setSizePolicy( Qt::Horizontal, QskSizePolicy::Preferred );

        auto* textInput4 = new QskTextInput( this );
        textInput4->setEchoMode( QskTextInput::Password );
        textInput4->setPasswordMaskDelay( 1000 );
        textInput4->setMaxLength( 8 );
        textInput4->setText( "12345678" );
        textInput4->setSizePolicy( Qt::Horizontal, QskSizePolicy::Preferred );
    }
};

class LocaleListView final : public QskListView
{
    Q_OBJECT

  public:
    LocaleListView( QQuickItem* parentItem = nullptr )
        : QskListView( parentItem )
        , m_maxWidth( 0.0 )
    {
        for ( auto language :
            {
                QLocale::Bulgarian, QLocale::Czech, QLocale::German,
                QLocale::Danish, QLocale::English, QLocale::Spanish,
                QLocale::Finnish, QLocale::French, QLocale::Hungarian,
                QLocale::Italian, QLocale::Japanese, QLocale::Latvian,
                QLocale::Lithuanian, QLocale::Dutch, QLocale::Portuguese,
                QLocale::Romanian, QLocale::Russian, QLocale::Slovenian,
                QLocale::Slovak, QLocale::Turkish, QLocale::Chinese
            } )
        {
            if ( language == QLocale::English )
            {
                append( QLocale( QLocale::English, QLocale::UnitedStates ) );
                append( QLocale( QLocale::English, QLocale::UnitedKingdom ) );
            }
            else
            {
                append( QLocale( language ) );
            }
        }

        setSizePolicy( Qt::Horizontal, QskSizePolicy::Fixed );
        setPreferredWidth( columnWidth( 0 ) + 20 );

        setScrollableSize( QSizeF( columnWidth( 0 ), rowCount() * rowHeight() ) );

        connect( this, &QskListView::selectedRowChanged,
            [ this ]( int row ) { Q_EMIT selected( localeAt( row ) ); } );
    }

    int rowCount() const override
    {
        return m_values.count();
    }

    int columnCount() const override
    {
        return 1;
    }

    qreal columnWidth( int ) const override
    {
        if ( m_maxWidth == 0.0 )
        {
            const QFontMetricsF fm( effectiveFont( Text ) );

            for ( const auto& entry : m_values )
                m_maxWidth = qMax( m_maxWidth, qskHorizontalAdvance( fm, entry.first ) );

            const auto padding = paddingHint( Cell );
            m_maxWidth += padding.left() + padding.right();
        }

        return m_maxWidth;
    }

    qreal rowHeight() const override
    {
        const QFontMetricsF fm( effectiveFont( Text ) );
        const auto padding = paddingHint( Cell );

        return fm.height() + padding.top() + padding.bottom();
    }

    QVariant valueAt( int row, int ) const override
    {
        return m_values[ row ].first;
    }

    QLocale localeAt( int row ) const
    {
        if ( row >= 0 && row < m_values.size() )
            return m_values[ row ].second;

        return QLocale();
    }

  Q_SIGNALS:
    void selected( const QLocale& );

  private:
    inline void append( const QLocale& locale )
    {
        m_values += qMakePair( nativeLocaleString( locale ), locale );
    }

    QVector< QPair< QString, QLocale > > m_values;
    mutable qreal m_maxWidth;
};

class Window : public QskWindow
{
  public:
    Window()
    {
        populate();
    }

    void populate()
    {
        auto box = new QskLinearBox( Qt::Horizontal );
        box->setSpacing( 10 );
        box->setPadding( 10 );
        box->setPanel( true );

        auto listView = new LocaleListView( box );
        auto inputBox = new InputBox( box );

        /*
            Disable Qt::ClickFocus, so that the input panel stays open
            when selecting a different locale
         */
        listView->setFocusPolicy( Qt::TabFocus );

        connect( listView, &LocaleListView::selected,
            inputBox, &InputBox::setLocale );

        addItem( box );
        addItem( new QskFocusIndicator() );
    }
};

int main( int argc, char* argv[] )
{
#ifdef ITEM_STATISTICS
    QskObjectCounter counter( true );
#endif

    qputenv( "QT_IM_MODULE", "skinny" );

    QGuiApplication app( argc, argv );

    SkinnyShortcut::enable( SkinnyShortcut::AllShortcuts );

#if 1
    // We don't want to have the input panel in a top level window.
    qskDialog->setPolicy( QskDialog::EmbeddedBox );
#endif

    Window window1;
    window1.setObjectName( "Window 1" );
    window1.setTitle( "Window 1" );
    window1.resize( 600, 600 );
    window1.show();

#if 1
    Window window2;
    window2.setObjectName( "Window 2" );
    window2.setTitle( "Window 2" );
    window2.setX( window1.x() + 100 );
    window2.resize( 600, 600 );
    window2.show();
#endif

    QskInputContext::instance()->setFactory( new InputContextFactory() );
    return app.exec();
}

#include "main.moc"