#include <QHBoxLayout>
#include <QRandomGenerator>
#include <cmath>
#include <limits>
#include <qcustomplot.h>
#include <QMessageBox>

#include "centralwidget.h"
#include "filemanager.h"
#include "pointcalculate.h"
#include "logger.h"
#include "xlsxhandler.h"

CentralWidget::CentralWidget(QWidget *parent)
    : QWidget(parent)
    ,_customPlot(new LocalCustomPlot(this))
    //    ,_customPlot(new QCustomPlot(this))
    ,_analysisMode(AnalysisMode::Null)
    ,_currentCurve(nullptr)
    ,_axisMode(AxisMode::SingleY)
{
    setMouseTracking(true);

    setStyleSheet("background-color: lightgray;");
    resize(888, 666);

    QHBoxLayout *layout = new QHBoxLayout();
    layout->setMargin(0);
    layout->addWidget(_customPlot);
    this->setLayout(layout);

    // 创建两条竖线
    _line1 = new QCPItemStraightLine(_customPlot);
    _line1->point1->setCoords(20, _customPlot->yAxis->range().lower);
    _line1->point2->setCoords(20, _customPlot->yAxis->range().upper);
    _line1->setPen(QPen(Qt::red));
    _line1->setSelectable(true);

    _line2 = new QCPItemStraightLine(_customPlot);
    _line2->point1->setCoords(40, _customPlot->yAxis->range().lower);
    _line2->point2->setCoords(40, _customPlot->yAxis->range().upper);
    _line2->setPen(QPen(Qt::red));
    _line2->setSelectable(true);

    // 安装事件过滤器
    //    _graph = _customPlot->addGraph(0);
    //    _eventHandler = new EventHandler(_customPlot, _line1, _line2, _graph, nullptr);

    _eventHandler = new EventHandler(_customPlot, _line1, _line2, nullptr);
    _eventHandler->setEnable(true);

    _customPlot->installEventFilter(_eventHandler);
    _customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);
    //    _customPlot->setInteractions( QCP::iRangeZoom | QCP::iSelectPlottables);
    //    _customPlot->setInteractions(QCP::iSelectPlottables);

    connect(_eventHandler,&EventHandler::sigSendLineXCoord,
            this,&CentralWidget::sigSendLineXCoord);

    setEventHandlerEnable(false);
    //
#if 0
    // init data
    QVector<double> x(101), y(101);
    for (int i = 0; i < 101; i++) {
        x[i] = i / 50.0 - 1;//设置x的范围为-1~1
        y[i] = x[i] * x[i];
    }

    _customPlot->graph(0)->setData(x, y);
    //设置坐标轴标签
    _customPlot->xAxis->setLabel("x coordinates");
    _customPlot->yAxis->setLabel("y coordinates");
    //设置坐标轴范围，以便我们可以看到全部数据
    _customPlot->xAxis->setRange(0, 1);
    _customPlot->yAxis->setRange(0, 100);
    _customPlot->replot();
#endif

    // 设置坐标轴标签
    _customPlot->xAxis->setLabel("Temp/℃");
    _customPlot->yAxis->setLabel("DSC/mW");
    // 设置坐标轴范围，以便我们可以看到全部数据
    _customPlot->xAxis->setRange(0,100);
    _customPlot->yAxis->setRange(0,20);

    // startTimer(300);
}

CentralWidget::~CentralWidget()
{
}

void CentralWidget::switchAxisMode()
{
    if(Global::_mode != Global::Mode::Analysis){
        return;
    }

    if(_axisMode == AxisMode::SingleY){
        _axisMode = AxisMode::DoubleY;

        _customPlot->yAxis2->setVisible(true);
        _customPlot->yAxis2->setLabel("Time/min");

        for(Global::CurveFileData& cfd:Global::_curveFileDataVtr){
            for(Global::PhaseTotalInfo& pti:cfd.phaseTotalVtr){

                QVector<Global::ExperimentData> dataVtr;
                QVector<double> tVtr,xVtr, yVtr;
                int index = 0;
                for (Global::ExperimentData &ed : pti.dataVtr)
                {
                    tVtr.push_back(index++);
                    xVtr.push_back(ed.sampleTemp);
                    yVtr.push_back(ed.runTime);
                }

                double yMin = yVtr.first();
                double yMax = yVtr.last();
                double tick = (yMax - yMin) / 4;

                double axisMin = yMin - tick;
                double axisMax = yMax + tick;
                _customPlot->yAxis2->setRange(axisMin,axisMax);

                QCPCurve* curve = new QCPCurve(_customPlot->xAxis, _customPlot->yAxis2);
                curve->setData(tVtr, xVtr, yVtr);
                curve->setPen(QPen(QColor(Qt::red)));
                curve->setObjectName(Global::CurveOfTimeTypeObjectName);

                //    logde<<"plottableCount count:"<<_customPlot->plottableCount();
            }
        }
    }else{
        _axisMode = AxisMode::SingleY;

        _customPlot->yAxis2->setVisible(false);

        //        logde<<"graph count:"<<_customPlot->plottableCount();

        for (int i = _customPlot->plottableCount() - 1; i >= 0; --i) {
            QCPAbstractPlottable* plottable = _customPlot->plottable(i);
            if (auto curve = dynamic_cast<QCPCurve*>(plottable)) {
                if(curve && curve->objectName() == Global::CurveOfTimeTypeObjectName){
                    _customPlot->removePlottable(curve);
                }
            }
        }
    }

    _customPlot->replot();
}

void CentralWidget::setAnalysisMode(const CentralWidget::AnalysisMode mode)
{
    _analysisMode = mode;

    switch (mode)
    {
    case AnalysisMode::Null:
        _customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);
        break;
    case AnalysisMode::NumericalLabel:
    case AnalysisMode::StartPoint:
    case AnalysisMode::StopPoint:
    case AnalysisMode::PeakSynthesisAnalysis:
    case AnalysisMode::GlassTransition:
        _customPlot->setInteractions(QCP::iSelectPlottables);
        setEventHandlerEnable(true);
        break;
    default:
        break;
    }
}

void CentralWidget::slotModeModify(const Global::Mode mode)
{
    if (Global::Mode::Experiment == mode)
    {
#if 0
        if (_customPlot->graphCount() > 0 && _currentGraph)
        {
            // 清除第一个图表上的数据
            _currentGraph->setData(QVector<double>(), QVector<double>());
        }
#endif

        // 创建画布,设置画布上的点数据
        //        _graph = _customPlot->addGraph();

        // 设置坐标轴标签
        _customPlot->xAxis->setLabel("Temp/℃");
        _customPlot->yAxis->setLabel("DSC/mW");
        // 设置坐标轴范围，以便我们可以看到全部数据
        _customPlot->xAxis->setRange(0, 400);
        _customPlot->yAxis->setRange(-20, 20);
    }
    else if (Global::Mode::Analysis == mode)
    {
        qDebug() << "file close...";
    }
}

void CentralWidget::slotRecvCommonData(const CommonData &cd)
{
    //    logde<<"slotRecvCommonData...";

    static double index = 0.0;

    if(!_currentCurve){
        logde<<"_currentCurve is nullptr";
        _currentCurve = new QCPCurve(_customPlot->xAxis, _customPlot->yAxis);
    }

    //    logde<<"temp:"<<cd.sample_temp<<",dsc:"<<cd.dsc;

    _currentCurve->addData(index++,cd.sample_temp, cd.dsc);

    //    _customPlot->rescaleAxes();
    _customPlot->replot();

    //    return;

    // Record data.
    if(!Global::_currentCurveExperimentDataPtr){
        loger<<"_currentCurveExperimentDataPtr is nullptr.";
        exit(0);
    }else{
        Global::ExperimentData ed;
        ed.dsc = cd .dsc;
        ed.sampleTemp = cd.sample_temp;
        ed.runTime = cd.add_run_time;
        ed.constantTempTime = cd.add_constan_temp_time;

        Global::_currentCurveExperimentDataPtr->dataVtr.push_back(ed);
        Global::_currentCurveExperimentDataPtr->curve = _currentCurve;
    }
}

void CentralWidget::slotRecvAnalysisFileName(const QString &filePath)
{
    if(_analysisFilePathVtr.contains(filePath)){
        return;
    }

    qDebug() << "slotRecvAnalysisFileName" << filePath;

    Global::CurveFileData cfd;
    if(XlsxHandler::readFile(filePath,cfd) != 0){
        QMessageBox::warning((QWidget*)this->parent(), "warnning", "File parse error.");
        return;
    }

    QFileInfo fileInfo(filePath);
    cfd.fileName = fileInfo.fileName();

    for(int i = 0;i < cfd.phaseTotalVtr.size();i++){
        Global::PhaseTotalInfo& pti = cfd.phaseTotalVtr[i];

        logde<<"data Vtr size:"<<pti.dataVtr.size();

        PointCalculate::setExperimentData(pti.dataVtr);

        QPair<QPointF,QPointF>startEndPointPair =  PointCalculate::getStartAndEndPoint();

        QPointF endPoint = startEndPointPair.second;
        _customPlot->xAxis->setRange(0, endPoint.x() / 3 * 4);

        //QPointF peakPoint = PointCalculate::getPeakPoint();
        QPair<float, float> maxMinPair = PointCalculate::getMaxMinValue();
        float absY = std::abs(maxMinPair.first - maxMinPair.second);
        _customPlot->yAxis->setRange(- absY * 2,absY *2);

        _customPlot->yAxis->setLabel("DSC/mW");
        _customPlot->xAxis->setLabel("Temp/℃");

        QVector<Global::ExperimentData> dataVtr;
        QVector<double> tVtr,xVtr, yVtr;
        int index = 0;
        for (Global::ExperimentData &ed : pti.dataVtr)
        {
            tVtr.push_back(index++);
            xVtr.push_back(ed.sampleTemp);
            yVtr.push_back(ed.dsc);
        }

        _currentCurve = new QCPCurve(_customPlot->xAxis, _customPlot->yAxis);
        _currentCurve->setData(tVtr, xVtr, yVtr);
        _currentCurve->setSelectable(QCP::stWhole); // 设置曲线可选

        pti.curve = _currentCurve;
    }

    // Add data to global parameter.
    Global::_curveFileDataVtr.push_back(cfd);

    _customPlot->rescaleAxes();
    _customPlot->replot();
}

void CentralWidget::slotAnalysisSettingApply()
{
    switch (_analysisMode) {
    case AnalysisMode::NumericalLabel:
    {
        QPointF selectPoint = PointCalculate::getClosestPointByX(
                    _line1->point1->coords().x());

        logde<<"lin1 x:"<<_line1->point1->coords().x();

        if(selectPoint.isNull()){
            QMessageBox::warning((QWidget*)this->parent(), "warnning", "曲线选择错误.");
            return;
        }

        drawText(selectPoint,
                 PointCalculate::textFormatNumbericalLabel(selectPoint));

        break;
    }
    case AnalysisMode::StartPoint:
    case AnalysisMode::StopPoint:{
        double x1 = _line1->point1->coords().x();
        double x2 = _line2->point1->coords().x();
        PointCalculate::setRegionPointX(x1,x2);

        QPair<QPointF, QPointF> startEndPointPair =
                PointCalculate::calculateStartAndEndPoint();

        if(_analysisMode == AnalysisMode::StartPoint){
            drawText(startEndPointPair.first,
                     PointCalculate::textFormatStartPoint(startEndPointPair.first));
        }else{
            drawText(startEndPointPair.second,
                     PointCalculate::textFormatEndPoint(startEndPointPair.second));
        }

        break;
    }
    case AnalysisMode::PeakSynthesisAnalysis:
    {
        double x1 = _line1->point1->coords().x();
        double x2 = _line2->point1->coords().x();

        fillGraph(x1,x2);

        PointCalculate::setRegionPointX(x1,x2);

        //enthalpy
        double sampleWeight = 0.0f;
        for(Global::CurveFileData& cfd:Global::_curveFileDataVtr){
            for(Global::PhaseTotalInfo& pti:cfd.phaseTotalVtr){
                if(_currentCurve && _currentCurve == pti.curve){
                    sampleWeight = cfd.ei.sampleWeight.toDouble();
                }
            }
        }
        logde<<"sample weight:"<<sampleWeight;

        double enthalpyValue = PointCalculate::calculateArea() / sampleWeight;

        //peak
        QPointF peakPoint = PointCalculate::getPeakPoint();

        //start point and end point
        QPair<QPointF, QPointF> startEndPointPair =
                PointCalculate::calculateStartAndEndPoint();

        logde<<"start,end:"<<startEndPointPair.first.x()<<","
            <<startEndPointPair.second.x();

        if(Global::_displayTimeValue){
            double peakPointTime = PointCalculate::obtainTimeValueBasedOnTemperatureValue(peakPoint.x());
            double startPointTime = PointCalculate::obtainTimeValueBasedOnTemperatureValue(startEndPointPair.first.x());
            double endPointTime = PointCalculate::obtainTimeValueBasedOnTemperatureValue(startEndPointPair.second.x());

            drawText(peakPoint,
                     PointCalculate::textFormatPeakPointWithTime(
                         enthalpyValue,
                         peakPointTime,
                         startPointTime,
                         endPointTime));
        }else{
            drawText(peakPoint,
                     PointCalculate::textFormatPeakPoint(enthalpyValue,
                                                         peakPoint.x(),
                                                         startEndPointPair.first.x(),
                                                         startEndPointPair.second.x()));
        }
        //
        break;
    }
    case AnalysisMode::GlassTransition:
    {
        //        glassTransitionHandle();
        glassTransitionHandle2();
        //
        break;
    }
    default:
        break;
    }
}

void CentralWidget::slotAnalysisSettingConfirm()
{
    slotAnalysisSettingApply();

    setAnalysisMode(CentralWidget::AnalysisMode::Null);

    _line1->setVisible(false);
    _line2->setVisible(false);

    emit sigRightDockWidgetHide();
}

void CentralWidget::slotAnalysisSettingUndo()
{
    clearData(ClearDataMode::Undo);
}

void CentralWidget::slotAnalysisSettingCancel()
{
    clearData(ClearDataMode::Undo);

    setAnalysisMode(CentralWidget::AnalysisMode::Null);

    _line1->setVisible(false);
    _line2->setVisible(false);

    emit sigRightDockWidgetHide();
}

void CentralWidget::slotAnalysisSettingLineXPoint(const int index, const double)
{

}

void CentralWidget::slotDrawCustomText(const QString str)
{
    QCPItemText* customLegendItem = new QCPItemText(_customPlot);
    customLegendItem->position->setTypeX(QCPItemPosition::ptAbsolute);
    customLegendItem->position->setTypeY(QCPItemPosition::ptAbsolute);
    customLegendItem->position->setCoords(150, 50); // 稍微向下移动
    customLegendItem->setText(str);

    QFont font("Arial", 10);
    customLegendItem->setFont(font);

    // 设置边框和背景
    customLegendItem->setPen(QPen(Qt::black));
    customLegendItem->setBrush(QBrush(Qt::white));

    // 禁止点选
    customLegendItem->setSelectable(false);
    customLegendItem->setObjectName("fixed");

    _customPlot->replot();
}

void CentralWidget::slotGetAxisInfo()
{
    QVector<AxisInfo> vtr;

    auto func = [&](QCPAxis* axis){
        AxisInfo ai;
        ai.visiable = axis->visible();
        ai.lower = axis->range().lower;
        ai.upper = axis->range().upper;

        vtr.push_back(ai);
    };

    func(_customPlot->xAxis);
    func(_customPlot->yAxis);
    func(_customPlot->yAxis2);

    emit sigGetAxisInfoWithData(vtr);
}

void CentralWidget::slotSetAxisSettings(const QVector<double>vtr)
{
    _customPlot->xAxis->setRange(vtr.at(0),vtr.at(1));
    _customPlot->yAxis->setRange(vtr.at(2),vtr.at(3));

    if(_customPlot->yAxis2->visible()){
        _customPlot->yAxis2->setRange(vtr.at(4),vtr.at(5));
    }

    _customPlot->replot();
}

void CentralWidget::timerEvent(QTimerEvent *event)
{
    _customPlot->replot();

#if 0
    // key的单位是秒
    double key = QDateTime::currentDateTime().toMSecsSinceEpoch() / 1000.0;
    // 添加数据
    // 使用随机数产生一条曲线
    // double value0 = realDataI();
    double value0 = QRandomGenerator::global()->bounded(10.123);
    _customPlot->graph(0)->addData(key, value0); // 添加数据到曲线

    // 删除8秒之前的数据。这里的8要和下面设置横坐标宽度的8配合起来
    // 才能起到想要的效果，可以调整这两个值，观察显示的效果。
    _customPlot->graph(0)->data()->remove(key - 80);
    // 自动设定graph(1)曲线y轴的范围，如果不设定，有可能看不到图像
    // 也可以用ui->customPlot->yAxis->setRange(up,low)手动设定y轴范围
    _customPlot->graph(0)->rescaleValueAxis(true);

    // 这里的8，是指横坐标时间宽度为8秒，如果想要横坐标显示更多的时间
    // 就把8调整为比较大到值，比如要显示60秒，那就改成60。
    // 这时removeDataBefore(key-8)中的8也要改成60，否则曲线显示不完整。

    _customPlot->yAxis->setRange(0, 20);                          // 设定x轴的范围
    _customPlot->xAxis->setRange(key + 0.25, 80, Qt::AlignRight); // 设定x轴的范围
    _customPlot->replot();
#endif
}

void CentralWidget::contextMenuEvent(QContextMenuEvent *event)
{
    qDebug()<<"left menu...";
    QPoint point =  event->globalPos();
    emit sigContextMenuShow(point);
}

void CentralWidget::glassTransitionHandle()
{
    QPointF point1 = PointCalculate::getClosestPointByX(_line1->point1->coords().x());
    QPointF point2 = PointCalculate::getClosestPointByX(_line2->point1->coords().x());

    logde<<"point1:"<<point1.x()<<","<<point1.y();
    logde<<"point2:"<<point2.x()<<","<<point2.y();

#if 0
    QCPItemStraightLine *line1 = new QCPItemStraightLine(_customPlot);
    line1->point1->setCoords(point1.x() - 5,point1.y());
    line1->point2->setCoords(point1.x() + 5,point1.y());
    line1->setPen(QPen(Qt::darkRed));
    line1->setSelectable(false);
    line1->setVisible(true);

    QCPItemStraightLine *line2 = new QCPItemStraightLine(_customPlot);
    line2->point1->setCoords(point2.x() - 5,point2.y());
    line2->point2->setCoords(point2.x() + 5,point2.y());
    line2->setPen(QPen(Qt::darkGreen));
    line2->setSelectable(false);
    line2->setVisible(true);

    _customPlot->replot();
#endif
    //
    PointCalculate::Line lineStrc1,lineStrc2,tangetLineStrc;

    lineStrc1.slope = 0.0;
    lineStrc1.intercept = point1.y();

    lineStrc2.slope = 0.0;
    lineStrc2.intercept  = point2.y();

    QPair<float,float> tangentLinePair = PointCalculate::getCurveInflectionPointTangent(point1.x(),point2.x());
    tangetLineStrc.slope = tangentLinePair.first;
    tangetLineStrc.intercept = tangentLinePair.second;

    QPointF intersection1 = PointCalculate::getIntersection(tangetLineStrc,lineStrc1);
    QPointF intersection2 = PointCalculate::getIntersection(tangetLineStrc,lineStrc2);

    //    logde<<"intersection1 x:"<<intersection1.x();
    //    logde<<"intersection2 x:"<<intersection2.x();

    //
    float averageY = (point1.y() + point2.y()) /2;
    logde<<"average Y:"<<averageY;
    QPointF averagePoint = PointCalculate::getClosestPointByY(point1.x(),point2.x(),averageY);

    //    logde<<"average y:"<<averageY;

    logde<<"averagePoint x,y:"<<averagePoint.x()<<","
        <<averagePoint.y();

    logde<<"glass T1:"<<intersection1.x()
        <<",Tg:"<<averagePoint.x()
       <<",T2:"<<intersection2.x();

    QString str = PointCalculate::textFormatGlassTranstion(intersection2.x(),
                                                           averagePoint.x(),
                                                           intersection1.x());
    //draw line
    ///line1
    QVector<double> xVtr,yVtr;
    xVtr.push_back(intersection1.x());
    xVtr.push_back(point1.x());

    yVtr.push_back(intersection1.y());
    yVtr.push_back(point1.y());

    QCPGraph *lineGraph1 = _customPlot->addGraph();
    lineGraph1->setData(xVtr, yVtr);
    _customPlot->replot();

    ///line2
    QVector<double> xVtr2,yVtr2;
    xVtr2.push_back(intersection2.x());
    xVtr2.push_back(point2.x());

    yVtr2.push_back(intersection2.y());
    yVtr2.push_back(point2.y());

    QCPGraph *lineGraph2 = _customPlot->addGraph();
    lineGraph2->setData(xVtr2, yVtr2);
    _customPlot->replot();

    //draw text
    drawText(averagePoint,str);

    _customPlot->replot();


#if 0
    // 创建一个圆形绘图项
    QCPItemEllipse *circle = new QCPItemEllipse(_customPlot);
    //    _customPlot->addItem(circle);

    // 设置圆形的位置和大小
    circle->topLeft->setCoords(-5, 5);
    circle->bottomRight->setCoords(5, -5);

    // 设置圆形的填充和边框颜色
    circle->setBrush(QBrush(Qt::cyan));
    circle->setPen(QPen(Qt::blue));
#endif

#if 0
    QCPItemStraightLine *line3 = new QCPItemStraightLine(_customPlot);
    line3->point1->setCoords(averagePoint.x() + 1,averagePoint.y() + 1);
    line3->point2->setCoords(averagePoint.x() - 1,averagePoint.y() - 1);
    line3->setPen(QPen(Qt::black));
    line3->setSelectable(false);
    line3->setVisible(true);

    _customPlot->replot();
#endif
}

void CentralWidget::glassTransitionHandle2()
{
    QPointF point1 = PointCalculate::getClosestPointByX(_line1->point1->coords().x());
    QPointF point2 = PointCalculate::getClosestPointByX(_line2->point1->coords().x());

    logde<<"point1:"<<point1.x()<<","<<point1.y();
    logde<<"point2:"<<point2.x()<<","<<point2.y();

    QVector<QPointF> point1Vtr = PointCalculate::getNearbyPointGroupByX(point1.x());
    QVector<QPointF> point2Vtr = PointCalculate::getNearbyPointGroupByX(point2.x());

    QVector<double> xVtr,yVtr;
    for(QPointF &p:point1Vtr){
        xVtr.append(p.x());
        yVtr.append(p.y());
    }

    PointCalculate::Line line1 =  calculateLinearRegression(xVtr,yVtr);

#if 1
    ///line1
    //    QVector<double> xVtr,yVtr;
    xVtr.clear();
    yVtr.clear();

    xVtr.push_back(point1.x());
    yVtr.push_back(point1.y());

    xVtr.push_back(point1.x() + 10);
    double y1 = line1.slope * (point1.x() + 10) + line1.intercept;
    yVtr.push_back(y1);

    QCPGraph *lineGraph1 = _customPlot->addGraph();
    lineGraph1->setData(xVtr, yVtr);
    QPen pen;
    pen.setColor(Qt::darkGreen);
    lineGraph1->setPen(pen);

#endif

    xVtr.clear();
    yVtr.clear();
    for(QPointF &p:point2Vtr){
        xVtr.append(p.x());
        yVtr.append(p.y());
    }

    PointCalculate::Line line2 =  calculateLinearRegression(xVtr,yVtr);

#if 1
    ///line2
    QVector<double> xVtr2,yVtr2;
    xVtr2.push_back(point2.x());
    yVtr2.push_back(point2.y());

    xVtr2.push_back(point2.x() - 10);
    double y2 = line2.slope * (point2.x() - 10) + line2.intercept;
    yVtr2.push_back(y2);

    QCPGraph *lineGraph2 = _customPlot->addGraph();
    lineGraph2->setData(xVtr2, yVtr2);
    lineGraph2->setPen(pen);

    _customPlot->replot();
#endif

    // inflection point.
    QVector<QPointF> originalPointVtr = PointCalculate::getPointVtrInXRange(point1.x(),point2.x());
    //    QVector<QPointF> pointVtr = PointCalculate::movingAveragePoint(originalPointVtr,3);
    QVector<QPointF> pointVtr = originalPointVtr;

    xVtr.clear();
    yVtr.clear();
    for(QPointF& p:pointVtr){
        xVtr.append(p.x());
        yVtr.append(p.y());
    }
    QMap<double, PointCalculate::Line>  tangentLines =
            PointCalculate::calculateTangentLine(xVtr,yVtr);

    double targetX = 0.0;
    PointCalculate::Line targetLine;
    double maxSlopeAbs = 0.0; // 初始化最大斜率绝对值为0
#if 0
    for (auto it = tangentLines.begin(); it != tangentLines.end(); ++it) {
        if (std::fabs(it.value().slope) > maxSlopeAbs) {
            maxSlopeAbs = std::fabs(it.value().slope); // 更新最大斜率绝对值

            targetX = it.key();
            targetLine = it.value();
        }
    }
#endif
    // new method
    for (auto it = tangentLines.begin(); it != tangentLines.end(); ++it) {
        if (std::fabs(it.value().slope) > maxSlopeAbs) {
            maxSlopeAbs = std::fabs(it.value().slope); // 更新最大斜率绝对值

            targetX = it.key();
            targetLine = it.value();

        }
    }

    int index = 0;
    QPointF prePoint,currentPoint,lastPoint;
    for (int i = 0;i < pointVtr.size();i++) {
        currentPoint = pointVtr[i];
        if(currentPoint.x() == targetX){
            index = i;
            break;
        }
    }

    prePoint = pointVtr[index - 1];
    lastPoint = pointVtr[index + 1];


    targetLine.slope = PointCalculate::calculateSlope(lastPoint.x(),lastPoint.y(),prePoint.x(),prePoint.y());
    targetLine.intercept =  currentPoint.y() - targetLine.slope * currentPoint.x();
    //
#if 1
    QPointF intersection1 = PointCalculate::getIntersection(targetLine,line1);
    QPointF intersection2 = PointCalculate::getIntersection(targetLine,line2);

    // graph 3
    xVtr.clear();
    yVtr.clear();

#if 0
    xVtr.push_back(point1.x());
    yVtr.push_back(point1.y());

    xVtr.push_back(point1.x());
    yVtr.push_back(point1.y());
#endif
#if 1
    xVtr.push_back(intersection1.x());
    yVtr.push_back(intersection1.y());

    xVtr.push_back(intersection2.x());
    yVtr.push_back(intersection2.y());
#endif

    QCPGraph *lineGraph3 = _customPlot->addGraph();
    lineGraph3->setData(xVtr, yVtr);
    lineGraph3->setPen(pen);
#endif

    _customPlot->replot();

    // point value
    double averageY = (point1.y() + point2.y()) / 2;

    QPointF averagePoint = PointCalculate::getClosestPointByY(point1.x(),point2.x(),averageY);

    QString str = PointCalculate::textFormatGlassTranstion(intersection1.x(),
                                                           averagePoint.x(),
                                                           intersection2.x());

    drawText(averagePoint,str);

}
// 使用最小二乘法计算线性回归
PointCalculate::Line CentralWidget::calculateLinearRegression(const QVector<double>& x, const QVector<double>& y) {
    PointCalculate::Line line;
    double sum_x = 0, sum_y = 0, sum_xy = 0, sum_xx = 0;
    size_t n = x.size();

    // 计算所需的总和
    for (size_t i = 0; i < n; ++i) {
        sum_x += x[i];
        sum_y += y[i];
        sum_xy += x[i] * y[i];
        sum_xx += x[i] * x[i];
    }

    // 计算斜率和截距
    double x_mean = sum_x / n;
    double y_mean = sum_y / n;
    double numerator = n * sum_xy - sum_x * sum_y;
    double denominator = n * sum_xx - sum_x * sum_x;
    line.slope = numerator / denominator;
    line.intercept = y_mean - line.slope * x_mean;

    return line;
}

// 二次多项式拟合函数
void CentralWidget::quadraticFit(const QVector<QPointF>& points, double& a, double& b, double& c) {
    int n = points.size();
    if (n < 3) {
        throw std::invalid_argument("At least three points are required for quadratic fit.");
    }

    double sumX = 0, sumY = 0, sumXX = 0, sumXY = 0, sumX2Y = 0;
    for (const QPointF& p : points) {
        sumX += p.x();
        sumY += p.y();
        sumXX += p.x() * p.x();
        sumXY += p.x() * p.y();
        sumX2Y += p.x() * p.x() * p.y();
    }

    double det = n * (sumXX * sumY - sumX * sumXY) - sumX * sumX * sumY + sumX * sumX2Y;
    a = (sumXX * sumY - sumX * sumXY) / det;
    b = (sumX2Y - n * sumXY) / det;
    c = (sumY - a * sumX - b * sumX) / n;
}

// 计算二次多项式拟合曲线的导数（切线斜率）
double CentralWidget::derivativeAt(const double a, const double b, const double x) {
    return 2 * a * x + b;
}


void CentralWidget::setEventHandlerEnable(const bool flag)
{
    logde<<"setEventHandlerEnable..."<<flag;

    // line visiable func
    auto lineVisiableFunc = [&](QCPItemStraightLine* line){
        line->setSelected(flag);
        line->setVisible(flag);
    };

    // todo. 当竖线隐藏时，需要设置不可选择模式。
    //    _eventHandler->setEnable(flag);

#if 1
    // move line to suitable position.
    double xMax = _customPlot->xAxis->range().upper;
    double xMin = _customPlot->xAxis->range().lower;

    //    logde<<"xMax:"<<xMax;

    //    QVector<double> ticks = _customPlot->xAxis->tickVector();
    //    int numTicks = ticks.size();
    //    logde<<"ticks:"<<numTicks;

    double range = xMax - xMin;
    double xLeft = xMin + range / 3;
    double xRight = xMin + range * 2 / 3;

    _line1->point1->setCoords(xLeft,_line1->point1->coords().y());
    _line1->point2->setCoords(xLeft,_line1->point2->coords().y());

    _line2->point1->setCoords(xRight,_line2->point1->coords().y());
    _line2->point2->setCoords(xRight,_line2->point2->coords().y());
#endif
    lineVisiableFunc(_line1);
    if(AnalysisMode::NumericalLabel != _analysisMode){
        lineVisiableFunc(_line2);
    }
    //
    _customPlot->replot();
}

QPointF CentralWidget::getTheCoordinatesOfTheTextBox(const QPointF point)
{
    double xMax = _customPlot->xAxis->range().upper;
    double xMin = _customPlot->xAxis->range().lower;

    logde<<"xMax:"<<xMax;

    QVector<double> ticks = _customPlot->xAxis->tickVector();
    int numTicks = ticks.size();
    logde<<"ticks:"<<numTicks;


    double distance = (xMax - xMin) / ticks.size();

    return QPointF(point.x() + distance,point.y());
}

void CentralWidget::drawText(const QPointF point, const QString text)
{
    QPointF textBoxPoint = getTheCoordinatesOfTheTextBox(point);

    // 创建标注文字（QCPItemText）
    QCPItemText *textLabel = new QCPItemText(_customPlot);
    textLabel->setPositionAlignment(Qt::AlignCenter);  // 对齐方式
    textLabel->position->setType(QCPItemPosition::ptPlotCoords);        // 使用数据坐标
    textLabel->position->setCoords(textBoxPoint.x(),textBoxPoint.y());  // 设置文本位置在指定点上方

    textLabel->setText(text);  // 设置文本内容
    QFont font(QFont("Arial", 10));
    textLabel->setFont(font);
    textLabel->setSelectedFont(font);
    textLabel->setSelectable(true);  // 设置为可选

    // 创建指向点的线段（QCPItemLine）
    QCPItemLine *arrow = new QCPItemLine(_customPlot);
    arrow->start->setParentAnchor(textLabel->left);  // 线段起点绑定到标注文字底部
    arrow->end->setCoords(point.x(),point.y());  // 线段终点设置为指定的点
    arrow->setHead(QCPLineEnding::esSpikeArrow);  // 添加箭头
    arrow->setPen(QPen(Qt::red, 1));

    // 重绘图表以显示文本标签和箭头
    _customPlot->replot();
}

void CentralWidget::fillGraph(const double x1, const double x2)
{
    double y1 = PointCalculate::getClosestPointByX(x1).y();
    double y2 = PointCalculate::getClosestPointByX(x2).y();

    QVector<double> xVtr,yVtr;
    xVtr.push_back(x1);
    xVtr.push_back(x2);

    yVtr.push_back(y1);
    yVtr.push_back(y2);

    QCPGraph *mainGraph = _customPlot->addGraph();
    mainGraph->setData(xVtr, yVtr);

    mainGraph->setPen(QPen(Qt::red, 1));

    QVector<Global::ExperimentData> curveDataVtr =
            PointCalculate::getDataInXRange(x1,x2);

    QCPGraph *fillGraph = _customPlot->addGraph();
    QVector<double> fillX, fillY;

    for(int i = 0;i < curveDataVtr.size();i++){
        Global::ExperimentData &ed = curveDataVtr[i];
        fillX<<ed.sampleTemp;
        fillY<<ed.dsc;
    }
    fillGraph->setData(fillX, fillY);

    fillGraph->setBrush(QBrush(Qt::green, Qt::SolidPattern));
    fillGraph->setChannelFillGraph(mainGraph);

    _customPlot->replot();
}

void CentralWidget::clearData(const CentralWidget::ClearDataMode mode)
{
    if(mode == ClearDataMode::All){
        // Clear the data of graph.

        for (int i = _customPlot->plottableCount() - 1; i >= 0; --i) {
            QCPAbstractPlottable* plottable = _customPlot->plottable(i);
            if (auto curve = dynamic_cast<QCPCurve*>(plottable)) {
                _customPlot->removePlottable(curve);
            }
        }

        // Clear data.
        Global::_curveExperimentDataVtr.clear();

        // Set lines visiable false.
        _line1->setVisible(false);
        _line2->setVisible(false);
    }

#if 0
    // Clear graph on plot.
    for (int i = _customPlot->graphCount() - 1; i >= 0; --i) {
        QCPGraph *graph = _customPlot->graph(i);
        _customPlot->removeGraph(graph);
    }
    _currentCurve = nullptr;
#endif

    // Delete items.
    QList<QCPAbstractItem *> itemsToKeep;
    itemsToKeep  << _line1 << _line2;

    for (int i = _customPlot->itemCount() - 1; i >= 0; --i) {
        QCPAbstractItem *item = _customPlot->item(i);
        if (!itemsToKeep.contains(item)) {
            _customPlot->removeItem(item);
        }
    }

    // 重绘图表以显示更改
    _customPlot->replot();
}

void CentralWidget::clearAllData()
{
    clearData(ClearDataMode::All);
}

QPixmap CentralWidget::getPixMap()
{
    return _customPlot->toPixmap();
}


void CentralWidget::slotAxisModify(const float temp)
{
    _customPlot->setInteractions(QCP::iRangeDrag | QCP::iRangeZoom | QCP::iSelectPlottables);

    float value = temp + 20;

    _customPlot->xAxis->setRange(10,value);
    _customPlot->yAxis->setRange(-5,5);
}