#include <QPainter>

#include "ZxBaseUtil.h"
#include "nmObjDelete.h"
#include "nmObjDeleteTool.h"

#include "nmSingalCenter.h"

#include "ZxPlot.h"

#include "zxGmyBase.h"

#include "nmObjLineCrack.h"
#include "nmDataFracture.h"
#include "nmPlotGraphicBinder.h"

nmObjDeleteTool::nmObjDeleteTool() : nmObjToolBase()
  , m_pPlot(nullptr)
{
  setText(tr("nObjDeleteTool"));
  m_oNot = NMOT_Delete;
  initDeleteCursor();
}

nmObjDeleteTool::nmObjDeleteTool(ZxPlot* pPlot)
  : nmObjToolBase()
  , m_pPlot(pPlot)
{
  setText(tr("nObjDeleteTool"));
  m_oNot = NMOT_Delete;
  nmDataLogFile::getInstance()->writeLog(" nmObjDeleteTool ++++++++ " + QString::number(m_oNot));
  initDeleteCursor();

}

nmObjDeleteTool::~nmObjDeleteTool()
{
    // 视口可能已销毁，由 QPointer 避免访问失效窗口。
    resetDeleteCursor();
}

void nmObjDeleteTool::initDeleteCursor()
{
    m_hadExplicitCursor = false;
    QPixmap icon(ZxBaseUtil::getDirOf(s_Dir_Res, "Icon") + "nmTrash.png");
    QPixmap cursorPixmap(40, 40);
    cursorPixmap.fill(Qt::transparent);
    QPainter painter(&cursorPixmap);

    // 仅显示小垃圾桶，以中心作为点击热点，大小不受画布缩放影响。
    painter.drawPixmap(cursorPixmap.rect(), icon, icon.rect());
    painter.end();
    m_deleteCursor = QCursor(cursorPixmap, 20, 20);
}

bool nmObjDeleteTool::updateDeleteCursor(const QPointF& pt)
{
    // 与点击使用同一命中规则，仅在绘图视口内切换光标。
    if (m_pObj != nullptr || QApplication::activeModalWidget() != nullptr ||
        findNearestDeleteObj(pt) == nullptr) {
        resetDeleteCursor();
        return false;
    }
    QWidget* viewport = getView()->viewport();
    if (m_cursorViewport != viewport) {
        resetDeleteCursor();
        m_cursorViewport = viewport;
        m_hadExplicitCursor = viewport->testAttribute(Qt::WA_SetCursor);
        m_previousCursor = viewport->cursor();
    }
    viewport->setCursor(m_deleteCursor);
    return true;
}

void nmObjDeleteTool::resetDeleteCursor()
{
    // 只恢复本工具设置的光标，不覆盖后来由其他工具设置的样式。
    if (m_cursorViewport &&
        m_cursorViewport->cursor().pixmap().cacheKey() == m_deleteCursor.pixmap().cacheKey()) {
        if (m_hadExplicitCursor) {
            m_cursorViewport->setCursor(m_previousCursor);
        } else {
            m_cursorViewport->unsetCursor();
        }
    }
    m_cursorViewport = nullptr;
}

bool nmObjDeleteTool::onMouseMove(const QPointF& pt)
{
    if (m_pObj != nullptr) {
        return nmObjToolBase::onMouseMove(pt);
    }
    // 命中时阻止图元自身的移动光标覆盖删除提示。
    return updateDeleteCursor(pt);
}

bool nmObjDeleteTool::onRightDown(const QPointF& pt)
{
    // 右键退出或打开菜单前恢复普通光标。
    resetDeleteCursor();
    return nmObjToolBase::onRightDown(pt);
}

void nmObjDeleteTool::onDeactivated()
{
    // 切换活动工具时释放自定义光标。
    resetDeleteCursor();
    nmObjToolBase::onDeactivated();
}

bool nmObjDeleteTool::onLeftDown(const QPointF& pt)
{
    if (m_pObj != nullptr) {
        return nmObjToolBase::onLeftDown(pt);
    }

    // 命中时接管按下事件，防止区域标记等图元的移动工具抢先处理抬起事件。
    return findNearestDeleteObj(pt) != nullptr;
}

bool nmObjDeleteTool::onLeftUp(const QPointF& pt)
{
    if (m_pObj != nullptr) {
        return nmObjToolBase::onLeftUp(pt);
    }

    // 按抬起位置重新命中，使用与悬停提示相同的对象筛选和距离规则。
    ZxObjBase* obj = findNearestDeleteObj(pt);
    if (obj != nullptr) {
        // 弹出确认框之前恢复，确认或取消后都不残留删除光标。
        resetDeleteCursor();
        nmSingalCenter::getInstance()->emitSigDeleteOneObj(obj->getName(), (void*)this);
    }
    return true;
}

ZxObjBase* nmObjDeleteTool::findNearestDeleteObj(const QPointF& pt)
{
    ZxRenderView* view = getView();
    if (m_pPlot == nullptr || view == nullptr) {
        return nullptr;
    }

    // 转为视口坐标后按 16 像素判断，保持不同缩放下的点击容差一致。
    const QPointF mousePos = view->mapFromScene(pt);
    const double hitRadius = 16.0;
    double nearestDistanceSquared = hitRadius * hitRadius;
    ZxObjBase* nearestObj = nullptr;
    zxGmyBase geometry;

    for (int i = 0; i < m_pPlot->getObjCount(); ++i) {
        ZxObjBase* obj = m_pPlot->getObjByIndex(i);
        if (obj == nullptr || !obj->isVisible()) {
            continue;
        }

        const bool isFracture = _isSame("nObjLineFracture", obj->getTagName());
        const bool isRegion = _isSame("nObjRegion", obj->getTagName());
        if (!isFracture && !isRegion &&
            !_isSame("nObjLineFault", obj->getTagName()) &&
            !_isSame("nObjPointWell", obj->getTagName()) &&
            !_isSame("nObjRegionMark", obj->getTagName())) {
            continue;
        }

        // 保留原有规则：未绑定数据及 DFN 生成的裂缝不参与单独删除。
        if (isFracture) {
            nmObjLineCrack* fracture = dynamic_cast<nmObjLineCrack*>(obj);
            nmPlotGraphicBinder* binder = fracture ? fracture->getGraphicBinder() : nullptr;
            nmDataFracture* data = binder ? binder->getCrackDataFor(fracture) : nullptr;
            if (data == nullptr || data->getFractureType().getValue() == tr("DFN")) {
                continue;
            }
        }

        QVector<QPointF> points = obj->getAllPos();
        if (points.isEmpty()) {
            continue;
        }
        for (int j = 0; j < points.count(); ++j) {
            points[j] = view->mapFromScene(points[j]);
        }

        double distance = QLineF(mousePos, points[0]).length();
        double distanceSquared = distance * distance;
        // 裂缝、断层按开放折线计算，只有区域包含末点到首点的闭合边。
        const int segmentCount = isRegion ? points.count() : points.count() - 1;
        for (int j = 0; j < segmentCount; ++j) {
            const QPointF& start = points[j];
            const QPointF& end = points[(j + 1) % points.count()];
            double segmentDistanceSquared;
            if (start == end) {
                // 重复节点按单点处理，避免零长度线段参与投影计算。
                distance = QLineF(mousePos, start).length();
                segmentDistanceSquared = distance * distance;
            } else {
                double t = 0.0;
                segmentDistanceSquared = geometry.pointSegmentDistanceSquared2D(mousePos, start, end, t);
            }
            distanceSquared = qMin(distanceSquared, segmentDistanceSquared);
        }

        // 范围内优先选择最近图元；距离相同时保留先命中的对象。
        if (distanceSquared <= hitRadius * hitRadius &&
            (nearestObj == nullptr || distanceSquared < nearestDistanceSquared)) {
            nearestDistanceSquared = distanceSquared;
            nearestObj = obj;
        }
    }
    return nearestObj;
}

void nmObjDeleteTool::onPaint(QPainter* painter, const ZxPaintParam& param)
{
    if (m_pObj == nullptr) {
        // 缩放或图元变化后重新判断命中，不再在画布上绘制垃圾桶。
        updateDeleteCursor(getCurrentPos());
    }
}