#include "graphicsItem/graphicsItemGroup.h"
#include <QGraphicsScene>
#include <QPainter>
#include <QStyleOption>

GraphicsItemGroup::GraphicsItemGroup(QGraphicsItem *parent)
    : AbstractShapeType<QGraphicsItemGroup>(parent)
{
    m_boundingRect = QRectF();

    //初始化缩放操作用的handle
    m_vecHanle.reserve(H_left);
    for(int i = H_leftTop; i <= H_left; i++)
    {
        ItemControlHandle* pHandle = new ItemControlHandle(this);
        pHandle->setType(T_resize);
        pHandle->setTag(i);
        m_vecHanle.push_back(pHandle);
    }
    for(int i = H_rotate_leftTop; i <= H_rotate_leftBottom; i++)
    {
        ItemControlHandle* pHandle = new ItemControlHandle(this);
        pHandle->setType(T_rotate);
        pHandle->setTag(i);
        m_vecHanle.push_back(pHandle);
    }

    setFlag(QGraphicsItem::ItemIsMovable, true);
    setFlag(QGraphicsItem::ItemIsSelectable, true);
    setFlag(QGraphicsItem::ItemSendsGeometryChanges, true);
    setAcceptHoverEvents(true);
}

GraphicsItemGroup::~GraphicsItemGroup()
{
}

QPainterPath GraphicsItemGroup::shape()
{
    QPainterPath path;
    path.addRect(m_boundingRect);
    return path;
}

void GraphicsItemGroup::paint(QPainter* painter, const QStyleOptionGraphicsItem* option, QWidget* widget)
{
    if (option->state & QStyle::State_Selected) //是选中状态,绘制选中框
    {
        int nPenWidth = 1;
        painter->setPen(QPen(QColor(70,70,70), nPenWidth, Qt::DashLine)); //蓝色的外框
        painter->setBrush(Qt::NoBrush);
        painter->drawRect(m_boundingRect_selected);

        //绘制变换原点
        // QPointF originPoint = transformOriginPoint();
        // painter->setBrush(Qt::red);
        // painter->drawEllipse(originPoint, 4, 4);
    }
}

void GraphicsItemGroup::contextMenuEvent(QGraphicsSceneContextMenuEvent* event)
{
    Q_UNUSED(event);
}

QVariant GraphicsItemGroup::itemChange(QGraphicsItem::GraphicsItemChange change, const QVariant& value)
{
    if (change == QGraphicsItem::ItemSelectedHasChanged)
    {
        QGraphicsItemGroup *group = dynamic_cast<QGraphicsItemGroup *>(parentItem());
        if(!group)
            setHandleVisible(value.toBool());
        else //在某一组群中，由组群展示是否选中，自身不做展示
        {
            setSelected(false);
            return QVariant::fromValue<bool>(false);
        }
    }
    return QGraphicsItemGroup::itemChange(change, value);
}

void GraphicsItemGroup::updateCoordinate() //当执行了resie和editShape函数后，boundingRect发生了变换，需要将item的原点(以中心点为原点)校准至boundingRect.center()
{
    if (!parentItem())
    {
        if (m_boundingRect.isNull())
        {
            m_boundingRect = QGraphicsItemGroup::boundingRect();
            m_dWidth = m_boundingRect.width();
            m_dHeight = m_boundingRect.height();
        }

        QPointF pt1, pt2, delta;
        pt1 = mapToScene(transformOriginPoint());
        pt2 = mapToScene(m_boundingRect.center());
        delta = pt1 - pt2;

        prepareGeometryChange();
        //boundingRect发生变化后原点偏离中心，将原点设为中心点，因为group内含有其它item，所以采用transform变换的方式
        //m_boundingRect = QRectF(-m_dWidth / 2, -m_dHeight / 2, m_dWidth, m_dHeight);
        setTransform(transform().translate(delta.x(), delta.y()));
        setTransformOriginPoint(m_boundingRect.center());
        //更改原点后自身绘制会在新坐标系下进行，会有跳转，所以需要将item整体做对应的移动
        moveBy(-delta.x(), -delta.y());
        updateHandles();
    }

    m_lastBoudingRect = m_boundingRect;

    //调用该组内所有item(过滤handle)相关函数
    foreach (QGraphicsItem *item, childItems())
    {
        GraphicsBaseItem *baseItem = qgraphicsitem_cast<GraphicsBaseItem *>(item);
        if (baseItem && !qgraphicsitem_cast<ItemControlHandle *>(baseItem))
        {
            baseItem->updateCoordinate();
        }
    }
}

void GraphicsItemGroup::resize(int nHandle,double dSX, double dSY, const QPointF& basePoint)
{
    switch (nHandle)
    {
    case H_left:
    case H_right:
        dSY = 1; //拖拽的是左点右点，为水平缩放，忽略垂直变化
        break;
    case H_top:
    case H_bottom:
        dSX = 1; //拖拽的是顶点底点，为垂直缩放，忽略水平变化
        break;
    default:
        break;
    }

    QTransform trans;
    //缩放是以图元原点（中心）位置为基准，所以每帧都先移动移动到想要的基准点，缩放之后再移回
    trans.translate(basePoint.x(), basePoint.y());
    trans.scale(dSX, dSY);
    trans.translate(-basePoint.x(), -basePoint.y());

    prepareGeometryChange();
    m_boundingRect = trans.mapRect(m_lastBoudingRect);
    m_dWidth = m_boundingRect.width();
    m_dHeight = m_boundingRect.height();
    updateHandles();

    //调用该组内所有item(过滤handle)相关函数
    foreach (QGraphicsItem *item, childItems())
    {
        GraphicsBaseItem *baseItem = qgraphicsitem_cast<GraphicsBaseItem *>(item);
        if (baseItem && !qgraphicsitem_cast<ItemControlHandle *>(baseItem))
        {
            baseItem->resize(nHandle, dSX, dSY, baseItem->mapFromParent(basePoint));
        }
    }
}

void GraphicsItemGroup::createOperationCopy()
{
    m_pOperationCopy = new QGraphicsPathItem(this->shape());
    m_pOperationCopy->setPen(Qt::DashLine);
    m_pOperationCopy->setPos(this->pos());
    m_pOperationCopy->setTransformOriginPoint(this->transformOriginPoint());
    m_pOperationCopy->setTransform(this->transform());
    m_pOperationCopy->setRotation(this->rotation());
    m_pOperationCopy->setScale(this->scale());
    m_pOperationCopy->setZValue(this->zValue());

    QGraphicsScene* scene = this->scene();
    if(scene && m_pOperationCopy)
    {
        scene->addItem(m_pOperationCopy);
        m_movingIniPos = this->pos();
    }
}

void GraphicsItemGroup::removeOperationCopy()
{
    QGraphicsScene* scene = this->scene();
    if(scene && m_pOperationCopy)
    {
        if(this->pos() != m_pOperationCopy->pos())
            this->setPos(m_pOperationCopy->pos()); //本体移动到副本的位置
        if(this->rotation() != m_pOperationCopy->rotation())
            this->setRotation(m_pOperationCopy->rotation()); //本体旋转至副本的角度

        scene->removeItem(m_pOperationCopy);
        delete m_pOperationCopy;
        m_pOperationCopy = nullptr;
    }
}

void GraphicsItemGroup::moveOperationCopy(const QPointF& distance)
{
    if(m_pOperationCopy)
        m_pOperationCopy->setPos(m_movingIniPos + distance);
}

void GraphicsItemGroup::rotateOperationCopy(const double& dAngle)
{
    if(m_pOperationCopy)
        m_pOperationCopy->setRotation(dAngle);
}

void GraphicsItemGroup::addItems(const QList<QGraphicsItem*>& items)
{
    foreach (QGraphicsItem *item, items)
    {
        item->setSelected(false);
        addToGroup(item);
        m_listItem.push_back(item);
    }

    updateCoordinate();
}