// vim: set tabstop=4 shiftwidth=4 noexpandtab:
/*
Gwenview: an image viewer
Copyright 2011 Aurélien Gâteau <agateau@kde.org>

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 Street, Fifth Floor, Cambridge, MA 02110-1301, USA.

*/
// Self
#include "contextbarbutton.moc"

// Local
#include "paintutils.h"

// KDE
#include <kiconloader.h>

// Qt
#include <QStyleOptionToolButton>
#include <QStylePainter>

namespace Gwenview {


/** How lighter is the border of context bar buttons */
const int CONTEXTBAR_BORDER_LIGHTNESS = 140;

/** How darker is the background of context bar buttons */
const int CONTEXTBAR_BACKGROUND_DARKNESS = 170;

/** How lighter are context bar buttons when under mouse */
const int CONTEXTBAR_MOUSEOVER_LIGHTNESS = 115;

/** Radius of ContextBarButtons */
const int CONTEXTBAR_RADIUS = 5;


struct ContextBarButtonPrivate {
};


ContextBarButton::ContextBarButton(const QString& iconName, QWidget* parent)
: QToolButton(parent)
, d(new ContextBarButtonPrivate) {
	const int size = KIconLoader::global()->currentSize(KIconLoader::Small);
	setIconSize(QSize(size, size));
	setAutoRaise(true);
	setIcon(SmallIcon(iconName));
}


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


void Gwenview::ContextBarButton::paintEvent(QPaintEvent*) {
	QStylePainter painter(this);
	painter.setRenderHint(QPainter::Antialiasing);
	QStyleOptionToolButton opt;
	initStyleOption(&opt);

	const QColor bgColor = palette().color(backgroundRole());
	QColor color = bgColor.dark(CONTEXTBAR_BACKGROUND_DARKNESS);
	QColor borderColor = bgColor.light(CONTEXTBAR_BORDER_LIGHTNESS);

	if (opt.state & QStyle::State_MouseOver && opt.state & QStyle::State_Enabled) {
		color = color.light(CONTEXTBAR_MOUSEOVER_LIGHTNESS);
		borderColor = borderColor.light(CONTEXTBAR_MOUSEOVER_LIGHTNESS);
	}

	const QRectF rectF = QRectF(opt.rect).adjusted(0.5, 0.5, -0.5, -0.5);
	const QPainterPath path = PaintUtils::roundedRectangle(rectF, CONTEXTBAR_RADIUS);

	// Background
	painter.fillPath(path, color);

	// Top shadow
	QLinearGradient gradient(rectF.topLeft(), rectF.topLeft() + QPoint(0, 5));
	gradient.setColorAt(0, QColor::fromHsvF(0, 0, 0, .3));
	gradient.setColorAt(1, Qt::transparent);
	painter.fillPath(path, gradient);

	// Left shadow
	gradient.setFinalStop(rectF.topLeft() + QPoint(5, 0));
	painter.fillPath(path, gradient);

	// Border
	painter.setPen(borderColor);
	painter.drawPath(path);

	// Content
	painter.drawControl(QStyle::CE_ToolButtonLabel, opt);
}


} // namespace
