/******************************************************************************
 * QSkinny - Copyright (C) 2016 Uwe Rathmann
 * This file may be used under the terms of the QSkinny License, Version 1.0
 *****************************************************************************/

#include "QskPushButtonSkinlet.h"
#include "QskPushButton.h"

#include "QskGraphic.h"
#include "QskTextOptions.h"

#include <qfontmetrics.h>
#include <qmath.h>

QskPushButtonSkinlet::QskPushButtonSkinlet( QskSkin* skin )
    : Inherited( skin )
{
    setNodeRoles( { PanelRole, GraphicRole, TextRole } );
}

QskPushButtonSkinlet::~QskPushButtonSkinlet() = default;

QRectF QskPushButtonSkinlet::subControlRect(
    const QskSkinnable* skinnable, QskAspect::Subcontrol subControl ) const
{
    const auto button = static_cast< const QskPushButton* >( skinnable );

    if ( subControl == QskPushButton::Text )
    {
        return textRect( button );
    }
    else if ( subControl == QskPushButton::Graphic )
    {
        return graphicRect( button );
    }
    else if ( subControl == QskPushButton::Panel )
    {
        return button->contentsRect();
    }

    return Inherited::subControlRect( skinnable, subControl );
}

QSGNode* QskPushButtonSkinlet::updateSubNode(
    const QskSkinnable* skinnable, quint8 nodeRole, QSGNode* node ) const
{
    const auto button = static_cast< const QskPushButton* >( skinnable );

    switch ( nodeRole )
    {
        case PanelRole:
        {
            return updateBoxNode( button, node, QskPushButton::Panel );
        }

        case TextRole:
        {
            return updateTextNode( button, node );
        }

        case GraphicRole:
        {
            return updateGraphicNode( button, node,
                button->graphic(), QskPushButton::Graphic );
        }
    }

    return Inherited::updateSubNode( skinnable, nodeRole, node );
}

QRectF QskPushButtonSkinlet::textRect( const QskPushButton* button ) const
{
    // buttonShift -> TODO

    QRectF r = button->innerBox( QskPushButton::Panel,
        subControlRect( button, QskPushButton::Panel ) );

    if ( button->hasGraphic() )
    {
        // in case of having text + graphic we put the text at the bottom

        qreal h = QFontMetricsF( button->effectiveFont( QskPushButton::Text ) ).height();
        if ( h < r.height() )
            r.setTop( r.bottom() - h );
    }

    return r;
}

QRectF QskPushButtonSkinlet::graphicRect( const QskPushButton* button ) const
{
    // buttonShift -> TODO
    QRectF r = button->innerBox( QskPushButton::Panel, button->contentsRect() );

    if ( !button->text().isEmpty() )
    {
        qreal h = textRect( button ).height() +
            button->metric( QskPushButton::Panel | QskAspect::Spacing );

        if ( h < r.height() )
            r.setBottom( r.bottom() - h );
        else
            r.setHeight( 0 );
    }

    const auto maxSize = button->graphicSourceSize();
    if ( maxSize.width() >= 0 || maxSize.height() >= 0 )
    {
        // limiting the size by graphicSize
        const qreal maxW = maxSize.width();
        const qreal maxH = maxSize.height();

        if ( maxW >= 0.0 && maxW < r.width() )
        {
            r.setX( r.center().x() - 0.5 * maxW );
            r.setWidth( maxW );
        }

        if ( maxH >= 0.0 && maxH < r.height() )
        {
            r.setY( r.center().y() - 0.5 * maxH );
            r.setHeight( maxH );
        }
    }

    const QSizeF sz = button->graphic().defaultSize();

    if ( !( r.isEmpty() || sz.isEmpty() ) )
    {
        // inner rectangle according to the aspect ratio

        const double scaleFactor =
            qMin( r.width() / sz.width(), r.height() / sz.height() );

        // early aligning to avoid pointless operations, that finally will
        // have no effect, when drawing to an integer based paint device

        const int w = qFloor( scaleFactor * sz.width() );
        const int h = qFloor( scaleFactor * sz.height() );
        const int x = qFloor( r.center().x() - 0.5 * w );
        const int y = qFloor( r.center().y() - 0.5 * h );

        r = QRectF( x, y, w, h );
    }

    return r;
}

QSGNode* QskPushButtonSkinlet::updateTextNode(
    const QskPushButton* button, QSGNode* node ) const
{
    const auto rect = subControlRect( button, QskPushButton::Text ).toAlignedRect();

    const QFontMetricsF fm( button->effectiveFont( QskPushButton::Text ) );
    if ( !button->clip() && ( rect.height() < fm.height() ) )
        return nullptr;

    const auto alignment = button->flagHint< Qt::Alignment >(
        QskPushButton::Text | QskAspect::Alignment, Qt::AlignCenter );

    return QskSkinlet::updateTextNode( button, node, rect, alignment,
        button->text(), button->textOptions(), QskPushButton::Text );
}

#include "moc_QskPushButtonSkinlet.cpp"