/* ============================================================
 *
 * This file is a part of digiKam project
 * https://www.digikam.org
 *
 * Date        : 2010-01-16
 * Description : drawing item view based on DCategorizedView
 *
 * Copyright (C) 2007      by Rafael Fernández López <ereslibre at kde dot org>
 * Copyright (C) 2009-2012 by Marcel Wiesweg <marcel dot wiesweg at gmx dot de>
 * Copyright (C) 2011-2019 by Gilles Caulier <caulier dot gilles at gmail dot com>
 *
 * 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, 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.
 *
 * ============================================================ */

#include "dcategorydrawer.h"

// Qt includes

#include <QPainter>
#include <QStyleOption>
#include <QApplication>

// Local includes

#include "dcategorizedview.h"
#include "dcategorizedsortfilterproxymodel.h"

namespace Digikam
{

class Q_DECL_HIDDEN DCategoryDrawer::Private
{
public:
    explicit Private(DCategorizedView* const view)
        : view(view)
    {
    }

    ~Private()
    {
    }

    DCategorizedView* view;
};


DCategoryDrawer::DCategoryDrawer(DCategorizedView *view)
     : QObject(view),
       d(new Private(view))
{
}

DCategoryDrawer::~DCategoryDrawer()
{
    delete d;
}

void DCategoryDrawer::drawCategory(const QModelIndex& index,
                                   int /*sortRole*/,
                                   const QStyleOption& option,
                                   QPainter* painter) const
{
    painter->setRenderHint(QPainter::Antialiasing);

    const QString category = index.model()->data(index, DCategorizedSortFilterProxyModel::CategoryDisplayRole).toString();
    const QRect optRect    = option.rect;
    QFont font(QApplication::font());
    font.setBold(true);
    const QFontMetrics fontMetrics = QFontMetrics(font);
    QColor outlineColor            = option.palette.text().color();
    outlineColor.setAlphaF(0.35);

    //BEGIN: top left corner
    {
        painter->save();
        painter->setPen(outlineColor);
        const QPointF topLeft(optRect.topLeft());
        QRectF arc(topLeft, QSizeF(4, 4));
        arc.translate(0.5, 0.5);
        painter->drawArc(arc, 1440, 1440);
        painter->restore();
    }
    //END: top left corner

    //BEGIN: left vertical line
    {
        QPoint start(optRect.topLeft());
        start.ry() += 3;
        QPoint verticalGradBottom(optRect.topLeft());
        verticalGradBottom.ry() += fontMetrics.height() + 5;
        QLinearGradient gradient(start, verticalGradBottom);
        gradient.setColorAt(0, outlineColor);
        gradient.setColorAt(1, Qt::transparent);
        painter->fillRect(QRect(start, QSize(1, fontMetrics.height() + 5)), gradient);
    }
    //END: left vertical line

    //BEGIN: horizontal line
    {
        QPoint start(optRect.topLeft());
        start.rx() += 3;
        QPoint horizontalGradTop(optRect.topLeft());
        horizontalGradTop.rx() += optRect.width() - 6;
        painter->fillRect(QRect(start, QSize(optRect.width() - 6, 1)), outlineColor);
    }
    //END: horizontal line

    //BEGIN: top right corner
    {
        painter->save();
        painter->setPen(outlineColor);
        QPointF topRight(optRect.topRight());
        topRight.rx() -= 4;
        QRectF arc(topRight, QSizeF(4, 4));
        arc.translate(0.5, 0.5);
        painter->drawArc(arc, 0, 1440);
        painter->restore();
    }
    //END: top right corner

    //BEGIN: right vertical line
    {
        QPoint start(optRect.topRight());
        start.ry() += 3;
        QPoint verticalGradBottom(optRect.topRight());
        verticalGradBottom.ry() += fontMetrics.height() + 5;
        QLinearGradient gradient(start, verticalGradBottom);
        gradient.setColorAt(0, outlineColor);
        gradient.setColorAt(1, Qt::transparent);
        painter->fillRect(QRect(start, QSize(1, fontMetrics.height() + 5)), gradient);
    }
    //END: right vertical line

    //BEGIN: text
    {
        QRect textRect(option.rect);
        textRect.setTop(textRect.top() + 7);
        textRect.setLeft(textRect.left() + 7);
        textRect.setHeight(fontMetrics.height());
        textRect.setRight(textRect.right() - 7);

        painter->save();
        painter->setFont(font);
        QColor penColor(option.palette.text().color());
        penColor.setAlphaF(0.6);
        painter->setPen(penColor);
        painter->drawText(textRect, Qt::AlignLeft | Qt::AlignVCenter, category);
        painter->restore();
    }
    //END: text
}

int DCategoryDrawer::categoryHeight(const QModelIndex& index, const QStyleOption& option) const
{
    Q_UNUSED(index);
    Q_UNUSED(option)

    QFont font(QApplication::font());
    font.setBold(true);
    QFontMetrics fontMetrics(font);

    const int height = fontMetrics.height() + 1  /* 1 pixel-width gradient */
                                            + 11 /* top and bottom separation */;
    return height;
}

int DCategoryDrawer::leftMargin() const
{
    return 0;
}

int DCategoryDrawer::rightMargin() const
{
    return 0;
}

DCategorizedView *DCategoryDrawer::view() const
{
    return d->view;
}

void DCategoryDrawer::mouseButtonPressed(const QModelIndex&, const QRect&, QMouseEvent* event)
{
    event->ignore();
}

void DCategoryDrawer::mouseButtonReleased(const QModelIndex&, const QRect&, QMouseEvent* event)
{
    event->ignore();
}

void DCategoryDrawer::mouseMoved(const QModelIndex&, const QRect&, QMouseEvent* event)
{
    event->ignore();
}

void DCategoryDrawer::mouseButtonDoubleClicked(const QModelIndex&, const QRect&, QMouseEvent* event)
{
    event->ignore();
}

void DCategoryDrawer::mouseLeft(const QModelIndex&, const QRect&)
{
}

} // namespace Digikam
