#include "QCPSizeHandleManager.h"

QCPSizeHandleManager::QCPSizeHandleManager(QCustomPlot *parentPlot)
            : QCPLayerable(parentPlot)
{

}

QCPSizeHandleManager::~QCPSizeHandleManager()
{
}

void QCPSizeHandleManager::addItem(QCPAbstractItem *item, bool showHandlesLines)
{
    if (!item || mHandles.contains(item))
        return;

    if (item->positions().size() < 2)  // 要改变item的大小，最起码要两个位置
        return;

    QList<QCPSizeHandle *> handles;
    foreach (auto *position, item->positions()) {
            handles.push_back(addHandleToPosition(position));
    }

    ControlItemData data;
    data.showHandlesLines = showHandlesLines;
    data.handles = handles;
    mHandles.insert(item, data);
}

void QCPSizeHandleManager::handleItemMove(QCPAbstractItem *item, const QPointF &delta)
{
    if (!item)
        return;

    auto positions = item->positions();
    foreach (auto *position, positions)
        position->setPixelPosition(position->pixelPosition() + delta);
}

void QCPSizeHandleManager::handleItemResize(QCPSizeHandle *sizeHandle, const QPointF &delta)
{
    if (!sizeHandle)
        return;

    auto *parentPosition = static_cast<QCPItemPosition *>(sizeHandle->position->parentAnchor());
    if (!parentPosition)
        return;

    parentPosition->setPixelPosition(parentPosition->pixelPosition() + delta);
}

QCPSizeHandle *QCPSizeHandleManager::addHandleToPosition(QCPItemPosition *position)
{
    auto *handle = new QCPSizeHandle(mParentPlot);
    handle->position->setParentAnchor(position);  // 设置QCPSizeHandle的父锚点为position
    handle->setVisible(false);
    handle->setLayer(QLatin1String("overlay"));
    return handle;
}

void QCPSizeHandleManager::applyDefaultAntialiasingHint(QCPPainter *painter) const
{
    applyAntialiasingHint(painter, mAntialiased, QCP::aeOther);
}

void QCPSizeHandleManager::draw(QCPPainter *painter)
{
    QMapIterator<QCPAbstractItem *, ControlItemData> i(mHandles);
    while (i.hasNext()) {
        i.next();
        auto data = i.value();
        if (!data.showHandlesLines)
            continue;

        painter->setPen(data.connectHandlePen);
        QVector<QPointF> lines;
        foreach (auto *handle, data.handles)
            lines.push_back(handle->position->pixelPosition());
        painter->drawLines(lines);
//        painter->drawPolyline(QPolygonF(lines));
    }
}