/**************************************************************************
* Otter Browser: Web browser controlled by the user, not vice-versa.
* Copyright (C) 2013 - 2019 Michal Dutkiewicz aka Emdek <michal@emdek.pl>
*
* 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 3 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, see <http://www.gnu.org/licenses/>.
*
**************************************************************************/

#include "ZoomWidget.h"
#include "../../../core/SettingsManager.h"
#include "../../../ui/MainWindow.h"
#include "../../../ui/ToolBarWidget.h"
#include "../../../ui/Window.h"

#include <QtGui/QMouseEvent>
#include <QtWidgets/QApplication>
#include <QtWidgets/QStyleOptionSlider>

namespace Otter
{

ZoomWidget::ZoomWidget(Window *window, QWidget *parent) : QSlider(parent),
	m_window(nullptr)
{
	const ToolBarWidget *toolBar(qobject_cast<ToolBarWidget*>(parent));

	setRange(0, 300);
	setTracking(true);
	setOrientation(Qt::Horizontal);
	setFocusPolicy(Qt::TabFocus);
	setSizePolicy(QSizePolicy::Preferred, QSizePolicy::Preferred);
	setTickPosition(QSlider::TicksBelow);
	setTickInterval(100);
	setWindow(window);

	if (toolBar && toolBar->getDefinition().isGlobal())
	{
		connect(toolBar, &ToolBarWidget::windowChanged, this, &ZoomWidget::setWindow);
	}
}

void ZoomWidget::changeEvent(QEvent *event)
{
	QSlider::changeEvent(event);

	if (event->type() == QEvent::LanguageChange)
	{
		setZoom(m_window ? m_window->getZoom() : SettingsManager::getOption(SettingsManager::Content_DefaultZoomOption).toInt());
	}
}

void ZoomWidget::mousePressEvent(QMouseEvent *event)
{
	if (!isEnabled() || event->button() != Qt::LeftButton)
	{
		QSlider::mousePressEvent(event);

		return;
	}

	QStyleOptionSlider option;
	option.initFrom(this);
	option.minimum = minimum();
	option.maximum = maximum();
	option.sliderPosition = value();
	option.sliderValue = value();

	const QRect handle(style()->subControlRect(QStyle::CC_Slider, &option, QStyle::SC_SliderHandle, this));
	const QRect groove(style()->subControlRect(QStyle::CC_Slider, &option, QStyle::SC_SliderGroove, this));
	int value(0);

	if (orientation() == Qt::Horizontal)
	{
		value = QStyle::sliderValueFromPosition(minimum(), maximum(), (event->x() - (handle.width() / 2) - groove.x()), (groove.right() - handle.width()));
	}
	else
	{
		value = QStyle::sliderValueFromPosition(minimum(), maximum(), (event->y() - (handle.height() / 2) - groove.y()), (groove.bottom() - handle.height()), true);
	}

	setZoom(value);

	if (handle.contains(event->pos()))
	{
		QSlider::mousePressEvent(event);
	}
}

void ZoomWidget::setWindow(Window *window)
{
	if (m_window)
	{
		disconnect(m_window, &Window::canZoomChanged, this, &ZoomWidget::setEnabled);
		disconnect(m_window, &Window::zoomChanged, this, &ZoomWidget::setZoom);
		disconnect(this, &ZoomWidget::valueChanged, m_window, &Window::setZoom);
	}

	m_window = window;

	setEnabled(m_window && m_window->canZoom());

	if (window)
	{
		setZoom(window->getZoom());

		connect(window, &Window::canZoomChanged, this, &ZoomWidget::setEnabled);
		connect(window, &Window::zoomChanged, this, &ZoomWidget::setZoom);
		connect(this, &ZoomWidget::valueChanged, window, &Window::setZoom);
	}
	else
	{
		setZoom(SettingsManager::getOption(SettingsManager::Content_DefaultZoomOption).toInt());
	}
}

void ZoomWidget::setZoom(int zoom)
{
	zoom = qMax(zoom, 10);

	setValue(zoom);
	setToolTip(tr("Zoom %1%").arg(zoom));
	setStatusTip(tr("Zoom %1%").arg(zoom));

	MainWindow *mainWindow(MainWindow::findMainWindow(this));

	if (mainWindow && (underMouse() || isSliderDown()))
	{
		QStatusTipEvent event(statusTip());

		QApplication::sendEvent(mainWindow, &event);
	}
}

QSize ZoomWidget::sizeHint() const
{
	return {150, QSlider::sizeHint().height()};
}

}
