/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
 *
 * Copyright (C) 2019 Tianjin KYLIN Information Technology Co., Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 */
#include "customstyle.h"

#include <QStyleOptionToolButton>
#include <QPainter>
#include <QPainterPath>
#include <QApplication>
#include <QDebug>

CustomStyle::CustomStyle(const QString& proxyStyleName, QObject* parent) : QProxyStyle (proxyStyleName)
{
    Q_UNUSED(parent);
}

void CustomStyle::drawComplexControl(QStyle::ComplexControl control, const QStyleOptionComplex* option, QPainter* painter, const QWidget* widget) const
{
    if (control == CC_ToolButton) {
        /// 我们需要获取ToolButton的详细信息，通过qstyleoption_cast可以得到
        /// 对应的option，通过拷贝构造函数得到一份备份用于绘制子控件
        /// 我们一般不用在意option是怎么得到的，大部分的Qt控件都能够提供了option的init方法

    }
    return QProxyStyle::drawComplexControl(control, option, painter, widget);
}

void CustomStyle::drawControl(QStyle::ControlElement element, const QStyleOption* option, QPainter* painter, const QWidget* widget) const
{

    switch (element) {
    case CE_ProgressBar: {
        if (const QStyleOptionProgressBar* pb  = qstyleoption_cast<const QStyleOptionProgressBar*>(option)) {
            QStyleOptionProgressBar subopt = *pb;
            subopt.rect = subElementRect(SE_ProgressBarGroove, pb, widget);
            proxy()->drawControl(CE_ProgressBarGroove, &subopt, painter, widget);
            subopt.rect = subElementRect(SE_ProgressBarContents, pb, widget);
            proxy()->drawControl(CE_ProgressBarContents, &subopt, painter, widget);

            //控件的当前进度的文字,看情况是否需要绘制
            //            if (pb->textVisible) {
            //                subopt.rect = subElementRect(SE_ProgressBarLabel, pb, widget);
            //                proxy()->drawControl(CE_ProgressBarLabel, &subopt, painter, widget);
            //            }
            return;
        }
        break;
    }
    case CE_ProgressBarGroove:
    {
        //控件的背景，看情况是否绘制
        return;
        if (const QStyleOptionProgressBar* pbg = qstyleoption_cast<const QStyleOptionProgressBar*>(option)) {
            const bool enable = pbg->state & State_Enabled;
            painter->save();
            painter->setRenderHint(QPainter::Antialiasing, true);
            painter->setPen(Qt::NoPen);
            painter->setBrush(pbg->palette.brush(enable ? QPalette::Active : QPalette::Disabled, QPalette::Window));
            painter->drawRect(pbg->rect);
            painter->restore();
            return;
        }
        break;
    }
    case CE_ProgressBarContents: {
        if (const QStyleOptionProgressBar* bar = qstyleoption_cast<const QStyleOptionProgressBar*>(option)) {
            if (bar->progress == bar->maximum)
                return;

            const bool enable = bar->state & QStyle::State_Enabled;
            const bool vertical = bar->orientation == Qt::Vertical;
            const bool inverted = bar->invertedAppearance;
            qint64 minimum = qint64(bar->minimum);
            qint64 maximum = qint64(bar->maximum);
            qint64 progress = qint64(bar->progress);
            qint64 totalSteps = qMax(Q_INT64_C(1), maximum - minimum);
            qint64 progressSteps = progress - bar->minimum;
            qint64 progressBarWidth = progressSteps * (vertical ? bar->rect.height() : bar->rect.width()) / totalSteps;

            int ProgressBarItem_Width = 4;
            int ProgressBarItem_Distance = 16;
            int distance = ProgressBarItem_Distance + ProgressBarItem_Width;
            int num = progressBarWidth / distance;
            int totalnum = (vertical ? bar->rect.height() : bar->rect.width()) / distance;

            bool reverse = (!vertical && (bar->direction == Qt::RightToLeft)) || vertical;
            if (inverted)
                reverse = !reverse;

            int ProgressBarItem_Hight = 16;
            QRect drawRect(bar->rect);
            if (vertical) {
                drawRect.setWidth(ProgressBarItem_Hight);
            } else {
                drawRect.setHeight(ProgressBarItem_Hight);
            }
            drawRect.moveCenter(bar->rect.center());

            QRect itemRect(drawRect);
            painter->save();
            painter->setPen(Qt::NoPen);
            painter->setRenderHints(QPainter::Antialiasing, true);
            for (int var = 0; var < totalnum; ++var) {
                if (var < num) {
                    if (enable)
                        painter->setBrush(bar->palette.brush(QPalette::Active, QPalette::Highlight));
                    else
                        painter->setBrush(bar->palette.color(QPalette::Active, QPalette::Highlight).light(150));
                } else {
                    painter->setBrush(bar->palette.brush(enable ? QPalette::Active : QPalette::Disabled, QPalette::Button));
                }

                if (vertical)
                    itemRect.setRect(drawRect.left(), !reverse ? drawRect.top() + var * distance : drawRect.bottom() - ProgressBarItem_Width - var * distance,
                                     drawRect.width(), ProgressBarItem_Width);
                else
                    itemRect.setRect(reverse ? drawRect.right() - ProgressBarItem_Width - var * distance : drawRect.left() + var * distance, drawRect.top(),
                                     ProgressBarItem_Width, drawRect.height());
                painter->drawRoundedRect(itemRect, ProgressBarItem_Width/2, ProgressBarItem_Width/2);
            }
            painter->restore();;
            return;
        }
        break;
    }
    default:
        break;
    }

    return QProxyStyle::drawControl(element, option, painter, widget);
}

void CustomStyle::drawItemPixmap(QPainter* painter, const QRect& rectangle, int alignment, const QPixmap& pixmap) const
{
    return QProxyStyle::drawItemPixmap(painter, rectangle, alignment, pixmap);
}

void CustomStyle::drawItemText(QPainter* painter, const QRect& rectangle, int alignment, const QPalette& palette, bool enabled, const QString& text, QPalette::ColorRole textRole) const
{
    return QProxyStyle::drawItemText(painter, rectangle, alignment, palette, enabled, text, textRole);
}

//绘制简单的颜色圆角等
void CustomStyle::drawPrimitive(QStyle::PrimitiveElement element, const QStyleOption* option, QPainter* painter, const QWidget* widget) const
{
    switch (element) {
    //绘制 ToolButton

    case PE_PanelButtonTool: {
        painter->save();
        painter->setRenderHint(QPainter::Antialiasing, true);
        painter->setPen(Qt::NoPen);
        painter->setBrush(QColor(0xff, 0xff, 0xff, 0x00));
        painter->drawRoundedRect(option->rect, 4, 4);
        if (option->state & State_MouseOver) {
            if (option->state & State_Sunken) {
                painter->setRenderHint(QPainter::Antialiasing,true);
                painter->setPen(Qt::NoPen);
                painter->setBrush(QColor(0xff, 0xff, 0xff, 0x14));
                painter->drawRoundedRect(option->rect, 4, 4);
            } else {
                painter->setRenderHint(QPainter::Antialiasing, true);
                painter->setPen(Qt::NoPen);
                painter->setBrush(QColor(0xff, 0xff, 0xff, 0x1f));
                painter->drawRoundedRect(option->rect, 4, 4);
            }
        }
        painter->restore();
        return;
    }
    case PE_PanelTipLabel: {
        painter->save();
        painter->setRenderHint(QPainter::Antialiasing, true);
        painter->setPen(Qt::NoPen);
        painter->setBrush(QColor(0xff, 0xff, 0x00, 0xff));
        painter->drawRoundedRect(option->rect, 4, 4);
        painter->restore();
        return;
    }break;
    case PE_PanelButtonCommand: {
        painter->save();
        painter->setRenderHint(QPainter::TextAntialiasing, true);
        painter->setPen(Qt::NoPen);
        painter->setBrush(QColor(0xff, 0xff, 0xff, 0x00));
        if (option->state & State_MouseOver) {
            if (option->state & State_Sunken) {
                painter->setRenderHint(QPainter::Antialiasing, true);
                painter->setPen(Qt::NoPen);
                painter->setBrush(QColor(0x3d, 0x6b, 0xe5, 0xff));
                painter->drawRoundedRect(option->rect, 4, 4);
            } else {
                painter->setRenderHint(QPainter::Antialiasing, true);
                painter->setPen(Qt::NoPen);
                painter->setBrush(QColor(0xff, 0xff, 0xff, 0x1f));
                painter->drawRoundedRect(option->rect.adjusted(2, 2, -2, -2), 4, 4);
            }
        }
        painter->restore();
        return;
    }break;
    }
    return QProxyStyle::drawPrimitive(element, option, painter, widget);
}

QPixmap CustomStyle::generatedIconPixmap(QIcon::Mode iconMode, const QPixmap& pixmap, const QStyleOption* option) const
{
    return QProxyStyle::generatedIconPixmap(iconMode, pixmap, option);
}

QStyle::SubControl CustomStyle::hitTestComplexControl(QStyle::ComplexControl control, const QStyleOptionComplex* option, const QPoint& position, const QWidget* widget) const
{
    return QProxyStyle::hitTestComplexControl(control, option, position, widget);
}

QRect CustomStyle::itemPixmapRect(const QRect& rectangle, int alignment, const QPixmap& pixmap) const
{
    return QProxyStyle::itemPixmapRect(rectangle, alignment, pixmap);
}

QRect CustomStyle::itemTextRect(const QFontMetrics& metrics, const QRect& rectangle, int alignment, bool enabled, const QString& text) const
{
    return QProxyStyle::itemTextRect(metrics, rectangle, alignment, enabled, text);
}

//
int CustomStyle::pixelMetric(QStyle::PixelMetric metric, const QStyleOption* option, const QWidget* widget) const
{
    switch (metric){
    case PM_ProgressBarChunkWidth: {
        int ProgressBarItem_Width = 4;
        int ProgressBarItem_Distance = 16;
        return ProgressBarItem_Width + ProgressBarItem_Distance;
    }
    case PM_ToolBarIconSize: {
        return (int)48*qApp->devicePixelRatio();
    }
    default:
        break;
    }
    return QProxyStyle::pixelMetric(metric, option, widget);
}

//
void CustomStyle::polish(QWidget* widget)
{
    if (widget) {
        if (widget->inherits("QTipLabel")) {
            widget->setAttribute(Qt::WA_TranslucentBackground);
            QPainterPath path;
            auto rect = widget->rect();
            rect.adjust(0, 0, 0, 0);
            path.addRoundedRect(rect, 6, 6);
            widget->setProperty("blurRegion", QRegion(path.toFillPolygon().toPolygon()));
        }
    }
    if (widget) {
        if (widget->inherits("QLable")) {
            const_cast<QWidget*> (widget)->setAttribute(Qt::WA_TranslucentBackground);
            widget->setAttribute(Qt::WA_TranslucentBackground);
            QPainterPath path;
            auto rect = widget->rect();
            rect.adjust(0, 0, 0, 0);
            path.addRoundedRect(rect, 6, 6);
            widget->setProperty("blurRegion", QRegion(path.toFillPolygon().toPolygon()));
        }
    }
    if (widget) {
        widget->setAttribute(Qt::WA_Hover);
        widget->inherits("QSlider");
        widget->installEventFilter(this);
    }

    return QProxyStyle::polish(widget);
}

void CustomStyle::polish(QApplication* application)
{
    return QProxyStyle::polish(application);
}

//
void CustomStyle::polish(QPalette& palette)
{
    QColor lightBlue(200, 0, 0);
    palette.setBrush(QPalette::Highlight, lightBlue);
}

void CustomStyle::unpolish(QWidget* widget)
{
    return QProxyStyle::unpolish(widget);
}

void CustomStyle::unpolish(QApplication* application)
{
    return QProxyStyle::unpolish(application);
}

QSize CustomStyle::sizeFromContents(QStyle::ContentsType type, const QStyleOption* option, const QSize& contentsSize, const QWidget* widget) const
{
    QSize newSize = contentsSize;
    switch (type) {
    case CT_ProgressBar: {
        int ProgressBarItem_Num = 20;
        int cw = proxy()->pixelMetric(QStyle::PM_ProgressBarChunkWidth, option, widget);
        newSize.setWidth(cw * ProgressBarItem_Num);
        return newSize;
    }
    default:
        break;
    }
    return QProxyStyle::sizeFromContents(type, option, contentsSize, widget);
}

QIcon CustomStyle::standardIcon(QStyle::StandardPixmap standardIcon, const QStyleOption* option, const QWidget* widget) const
{
    return QProxyStyle::standardIcon(standardIcon, option, widget);
}

QPalette CustomStyle::standardPalette() const
{
    return QProxyStyle::standardPalette();
}

//如果需要背景透明也许需要用到这个函数
int CustomStyle::styleHint(QStyle::StyleHint hint, const QStyleOption* option, const QWidget* widget, QStyleHintReturn* returnData) const
{
    switch (hint) {
    /// 让ScrollView viewport的绘制区域包含scrollbar和corner widget
    /// 这个例子中没有什么作用，如果我们需要绘制一个背景透明的滚动条
    /// 这个style hint对我们的意义应该很大，因为我们希望视图能够帮助
    /// 我们填充滚动条的背景区域，否则当背景透明时底下会出现明显的分割

    case SH_ScrollView_FrameOnlyAroundContents: {
        return false;
    }
    default:
        break;
    }
    return QProxyStyle::styleHint(hint, option, widget, returnData);
}

QRect CustomStyle::subControlRect(QStyle::ComplexControl control, const QStyleOptionComplex* option, QStyle::SubControl subControl, const QWidget* widget) const
{
    return QProxyStyle::subControlRect(control, option, subControl, widget);
}

QRect CustomStyle::subElementRect(QStyle::SubElement element, const QStyleOption* option, const QWidget* widget) const
{
    switch (element) {
    case SE_ProgressBarGroove:
    case SE_ProgressBarContents:
        return option->rect;

    default:
        break;
    }
    return QProxyStyle::subElementRect(element, option, widget);
}
