// Copyright (C) 2008  Lukas Lalinsky
//
// 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, Boston, MA 02110-1301 USA.

#include <QMouseEvent>
#include <QScrollBar>
#include <QDebug>
#include "databasemodelview.h"

DatabaseModelView::DatabaseModelView(QWidget *parent)
	: QGraphicsView(parent), m_handScrolling(false)
{
	setAlignment(Qt::AlignLeft | Qt::AlignTop);
	setRenderHint(QPainter::Antialiasing);
}

void
DatabaseModelView::setScene(QGraphicsScene *scene)
{
	QGraphicsView::setScene(scene);
	updateSceneRect2(scene->sceneRect());
	connect(scene, SIGNAL(sceneRectChanged(const QRectF &)), SLOT(updateSceneRect2(const QRectF &)));
}

void
DatabaseModelView::updateSceneRect2(const QRectF &rect)
{
	QRectF sceneRect = rect.united(QRectF(QPointF(0, 0), QPointF(100, 100)));
	setSceneRect(sceneRect);
}

void
DatabaseModelView::mousePressEvent(QMouseEvent *event)
{
	if (event->button() == Qt::MidButton) {
		m_handScrolling = true;
        m_handScrollingOrigin = QPoint(event->pos());
		m_handScrollingValueX = horizontalScrollBar()->value();
        m_handScrollingValueY = verticalScrollBar()->value();
		m_savedCursor = viewport()->cursor();
		viewport()->setCursor(Qt::ClosedHandCursor);
		event->accept();
		return;
	}
	QGraphicsView::mousePressEvent(event);
}

void
DatabaseModelView::mouseMoveEvent(QMouseEvent *event)
{
	if (m_handScrolling) {
		QPoint delta = event->pos() - m_handScrollingOrigin;
		horizontalScrollBar()->setValue(m_handScrollingValueX - delta.x());
		verticalScrollBar()->setValue(m_handScrollingValueY - delta.y());
		event->accept();
		return;
	}
	QGraphicsView::mouseMoveEvent(event);
}

void
DatabaseModelView::mouseReleaseEvent(QMouseEvent *event)
{
	if (m_handScrolling) {
		m_handScrolling = false;
		viewport()->setCursor(m_savedCursor);
		event->accept();
		return;
	}
	QGraphicsView::mouseReleaseEvent(event);
}