/************************************************************************
 **
 **  @file   vmaingraphicsview.cpp
 **  @author Roman Telezhynskyi <dismine(at)gmail.com>
 **  @date   November 15, 2013
 **
 **  @brief
 **  @copyright
 **  This source code is part of the Valentine project, a pattern making
 **  program, whose allow create and modeling patterns of clothing.
 **  Copyright (C) 2013 Valentina project
 **  <https://bitbucket.org/dismine/valentina> All Rights Reserved.
 **
 **  Valentina 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.
 **
 **  Valentina 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 Valentina.  If not, see <http://www.gnu.org/licenses/>.
 **
 *************************************************************************/

#include "vmaingraphicsview.h"

#include <QTimeLine>
#include <QWheelEvent>
#include <QApplication>
#include <QScrollBar>
#include "../tools/vabstracttool.h"

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VMainGraphicsView constructor.
 * @param parent parent object.
 */
VMainGraphicsView::VMainGraphicsView(QWidget *parent)
    :QGraphicsView(parent), _numScheduledScalings(0)
{
    this->setResizeAnchor(QGraphicsView::AnchorUnderMouse);
    this->setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
    this->setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief wheelEvent handle wheel events.
 * @param event wheel event.
 */
//cppcheck-suppress unusedFunction
void VMainGraphicsView::wheelEvent(QWheelEvent *event)
{
    int numSteps = event->delta() / 8 / 15;  // see QWheelEvent documentation

    _numScheduledScalings += numSteps;
    if (_numScheduledScalings * numSteps < 0)
    {  // if user moved the wheel in another direction, we reset
        _numScheduledScalings = numSteps;       // previously scheduled scalings
    }

    QTimeLine *anim = new QTimeLine(300, this);
    anim->setUpdateInterval(20);

    if (QApplication::keyboardModifiers() == Qt::ControlModifier)
    {// If you press CTRL this code will be executed
        connect(anim, &QTimeLine::valueChanged, this, &VMainGraphicsView::scalingTime);
    }
    else
    {
        connect(anim, &QTimeLine::valueChanged, this, &VMainGraphicsView::scrollingTime);
    }
    connect(anim, &QTimeLine::finished, this, &VMainGraphicsView::animFinished);
    anim->start();
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief scalingTime call each time when need handle scaling.
 * @param x value from 0.0 to 1.0
 */
void VMainGraphicsView::scalingTime(qreal x)
{
    Q_UNUSED(x);
    const QPointF p0scene = mapToScene(mapFromGlobal(QCursor::pos()));

    qreal factor = 1.0 + static_cast<qreal>(_numScheduledScalings) / 50.0;
    scale(factor, factor);

    const QPointF p1mouse = mapFromScene(p0scene);
    const QPointF move = p1mouse - this->mapFromGlobal(QCursor::pos()); // The move
    horizontalScrollBar()->setValue(static_cast<qint32>(move.x()) + horizontalScrollBar()->value());
    verticalScrollBar()->setValue(static_cast<qint32>(move.y()) + verticalScrollBar()->value());

    VAbstractTool::NewSceneRect(this->scene(), this);

    emit NewFactor(factor);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief scrollingTime call each time when need handle scrolling.
 * @param x value from 0.0 to 1.0
 */
void VMainGraphicsView::scrollingTime(qreal x)
{
    Q_UNUSED(x);
    qreal factor = 1.0;
    if (_numScheduledScalings < 0)
    {
        verticalScrollBar()->setValue(qRound(verticalScrollBar()->value() + factor*3.5));
        emit NewFactor(factor);
    }
    else
    {
        verticalScrollBar()->setValue(qRound(verticalScrollBar()->value() - factor*3.5));
        emit NewFactor(factor);
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief animFinished
 */
void VMainGraphicsView::animFinished()
{
    if (_numScheduledScalings > 0)
    {
        _numScheduledScalings--;
    }
    else
    {
        _numScheduledScalings++;
    }
    sender()->~QObject();
}

//---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomIn()
{
    scale(1.1, 1.1);
    VAbstractTool::NewSceneRect(this->scene(), this);
    emit NewFactor(1.1);
}

//---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomOut()
{
    scale(1.0/1.1, 1.0/1.1);
    VAbstractTool::NewSceneRect(this->scene(), this);
    emit NewFactor(1.0/1.1);
}

//---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomOriginal()
{
    QTransform trans = this->transform();
    trans.setMatrix(1.0, trans.m12(), trans.m13(), trans.m21(), 1.0, trans.m23(), trans.m31(), trans.m32(),
                    trans.m33());
    this->setTransform(trans);
    emit NewFactor(1.0);
}

//---------------------------------------------------------------------------------------------------------------------
void VMainGraphicsView::ZoomFitBest()
{
    QRectF rect = this->scene()->itemsBoundingRect();

    if (rect.isEmpty())
    {
        return;
    }

    this->fitInView(rect, Qt::KeepAspectRatio);
    emit NewFactor(this->transform().m11());
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief mousePressEvent handle mouse press events.
 * @param mousePress mouse press event.
 */
void VMainGraphicsView::mousePressEvent(QMouseEvent *mousePress)
{
    if (mousePress->button() & Qt::LeftButton)
    {
        switch (QGuiApplication::keyboardModifiers())
        {
            case Qt::ControlModifier:
                QGraphicsView::setDragMode(QGraphicsView::ScrollHandDrag);
                QGraphicsView::mousePressEvent(mousePress);
                break;
            default:
                QGraphicsView::mousePressEvent(mousePress);
                break;
        }
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief mouseReleaseEvent handle mouse release events.
 * @param event mouse release event.
 */
void VMainGraphicsView::mouseReleaseEvent(QMouseEvent *event)
{
    QGraphicsView::mouseReleaseEvent ( event );
    QGraphicsView::setDragMode( QGraphicsView::RubberBandDrag );
}