#include <QFileDialog>

#include "coefficientselectionform.h"
#include "ui_coefficientselectionform.h"
#include "confighandler.h"
#include "logger.h"
#include "global.h"

CoefficientSelectionForm::CoefficientSelectionForm(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::CoefficientSelectionForm)
{
    ui->setupUi(this);

    setWindowTitle("热焓校正系数选择");

#if 1
    ui->LineEditCoefficient->setText(
                QString::number(
                    ConfigHandler::_configMap[ConInstrumentCoefficientStr].toFloat(),
                    'f',3));
#endif

    ui->radioButtonSinglePointCoefficient->setChecked(true);
    ui->radioButtonSinglePointCoefficient->setChecked(false);

    on_radioButtonSinglePointCoefficient_toggled(true);
    on_radioButtonMultiPointCoefficient_toggled(false);

    ui->textEditFileContent->setReadOnly(true);
}

CoefficientSelectionForm::~CoefficientSelectionForm()
{
    delete ui;
}

void CoefficientSelectionForm::showEvent(QShowEvent *event)
{

}

void CoefficientSelectionForm::on_pushButtonCalculate_clicked()
{
    float theory = ui->LineEditTheory->text().toFloat();
    float measure = ui->LineEditActualMeasurement->text().toFloat();

    _instrumentCoefficient = theory/measure;
    ui->LineEditCoefficient->setText(QString::number(_instrumentCoefficient,'f',3));

}

void CoefficientSelectionForm::on_pushButtonConfirm_clicked()
{
    if(ui->radioButtonSinglePointCoefficient->isChecked()){
        ConfigHandler::_configMap[ConInstrumentCoefficientStr] = _instrumentCoefficient;
        ConfigHandler::writer();

        Global::_enthalpyCoefficientEnableFlag = false;
    }else{
        QVector<double> xVtr,yVtr;
        QJsonDocument jsonDoc = QJsonDocument::fromJson(_jsonStr.toUtf8());
        QJsonArray jsonArray = jsonDoc.array();

        for (const QJsonValue &value : jsonArray) {
            QJsonObject jsonObj = value.toObject();
            xVtr<<jsonObj["temperature"].toDouble();
            yVtr<<jsonObj["rate"].toDouble();
        }

        double coeff[3] = {0};
        quadraticLeastSquaresFit(xVtr.data(),yVtr.data(),xVtr.size(),coeff);

#if 0
        std::cout << "Fitted quadratic polynomial: y = "
                  << coeff[0] << "x^2 + "
                  << coeff[1] << "x + "
                  << coeff[2] << std::endl;
#endif


        logde<<"y:"<<coeff[0]<<","
            <<coeff[1]<<","
           <<coeff[2];

        Global::_enthalpyCoefficientEnableFlag = true;

        Global::_enthalpyCoefficientVtr.clear();
        Global::_enthalpyCoefficientVtr.push_back(coeff[2]);
        Global::_enthalpyCoefficientVtr.push_back(coeff[1]);
        Global::_enthalpyCoefficientVtr.push_back(coeff[0]);
    }

    hide();
}

void CoefficientSelectionForm::on_pushButtonExit_clicked()
{
#if 0
    ui->LineEditTheory->clear();
    ui->LineEditCoefficient->clear();

    ui->labelFilePath->clear();
    ui->textEditFileContent->clear();

    _jsonStr.clear();
#endif

    hide();
}
void CoefficientSelectionForm::quadraticLeastSquaresFit(double x[], double y[], int n, double coeff[]) {
    if (n < 3) {
        throw std::runtime_error("At least 3 data points are required for quadratic fit.");
    }

    // 计算各次幂的和
    double sum_x = 0.0, sum_x2 = 0.0, sum_x3 = 0.0, sum_x4 = 0.0;
    double sum_y = 0.0, sum_xy = 0.0, sum_x2y = 0.0;

    for (int i = 0; i < n; ++i) {
        sum_x += x[i];
        sum_x2 += x[i] * x[i];
        sum_x3 += x[i] * x[i] * x[i];
        sum_x4 += x[i] * x[i] * x[i] * x[i];
        sum_y += y[i];
        sum_xy += x[i] * y[i];
        sum_x2y += x[i] * x[i] * y[i];
    }

    // 构建法方程矩阵 A 和向量 b
    double A[3][3] = {
        {sum_x2, sum_x, n},
        {sum_x3, sum_x2, sum_x},
        {sum_x4, sum_x3, sum_x2}
    };
    double b[3] = {sum_x2y, sum_xy, sum_y};

    // 使用高斯消元法求解线性方程组
    for (int i = 0; i < 3; ++i) {
        // 寻找主元行
        int max_row = i;
        double max_val = std::fabs(A[i][i]);
        for (int j = i + 1; j < 3; ++j) {
            if (std::fabs(A[j][i]) > max_val) {
                max_val = std::fabs(A[j][i]);
                max_row = j;
            }
        }

        // 交换行
        if (max_row != i) {
            for (int k = 0; k < 3; ++k) {
                std::swap(A[i][k], A[max_row][k]);
            }
            std::swap(b[i], b[max_row]);
        }

        // 消元
        for (int j = i + 1; j < 3; ++j) {
            double factor = A[j][i] / A[i][i];
            for (int k = i; k < 3; ++k) {
                A[j][k] -= factor * A[i][k];
            }
            b[j] -= factor * b[i];
        }
    }

    // 回代求解
    coeff[2] = b[2] / A[2][2];
    for (int i = 1; i >= 0; --i) {
        double sum = 0.0;
        for (int j = i + 1; j < 3; ++j) {
            sum += A[i][j] * coeff[j];
        }
        coeff[i] = (b[i] - sum) / A[i][i];
    }
}
void CoefficientSelectionForm::on_pushButtonSelectFile_clicked()
{
    QString filePath = QFileDialog::getOpenFileName(
                nullptr, "选择 JSON 文件", "", "JSON 文件 (*.json);;所有文件 (*.*)");

    if (!filePath.isEmpty()) {
        QFile file(filePath);
        if (file.open(QIODevice::ReadOnly | QIODevice::Text)) {
            QTextStream in(&file);
            _jsonStr = in.readAll();
            file.close();

        } else {
            qDebug() << "无法打开文件：" << filePath;
            return;
        }
    } else {
        qDebug() << "未选择文件";
        return;
    }

    //
    ui->labelFilePath->setText(filePath);
    ui->textEditFileContent->setText(_jsonStr);
}

void CoefficientSelectionForm::on_radioButtonSinglePointCoefficient_toggled(bool checked)
{
    ui->LineEditTheory->setEnabled(checked);
    ui->LineEditCoefficient->setEnabled(checked);
    ui->LineEditActualMeasurement->setEnabled(checked);

    ui->pushButtonCalculate->setEnabled(checked);
#if 0
    if(checked){
        ui->LineEditTheory->setEnabled(true);
        ui->LineEditCoefficient->setEnabled(true);
        ui->LineEditActualMeasurement->setEnabled(true);

        ui->pushButtonCalculate->setEnabled(true);
    }else{

        ui->LineEditTheory->setEnabled(false);
        ui->LineEditCoefficient->setEnabled(false);
        ui->LineEditActualMeasurement->setEnabled(false);

        ui->pushButtonCalculate->setEnabled(false);
    }
#endif
}

void CoefficientSelectionForm::on_radioButtonMultiPointCoefficient_toggled(bool checked)
{
    ui->pushButtonSelectFile->setEnabled(checked);
    ui->textEditFileContent->setEnabled(checked);
#if 0
    if(checked){
        ui->pushButtonSelectFile->setEnabled(true);
        ui->textEditFileContent->setEnabled(true);
    }else{
        ui->pushButtonSelectFile->setEnabled(false);
        ui->textEditFileContent->setEnabled(false);
    }
#endif
}

void CoefficientSelectionForm::cubicLeastSquaresFit(
        double x[], double y[], int n, double coeff[])
{
    int i, j, k;
    double atemp[3] = {0}; // 存储x^0, x^1, x^2的和
    double b[3] = {0};     // 右侧向量

    // 计算各次幂的和
    for (i = 0; i < n; i++) {
        double xi = x[i];
        double xi_pow2 = xi * xi; // x^2

        // 累加atemp[0]到atemp[2]
        atemp[0] += 1; // x^0的和等于数据点个数
        atemp[1] += xi;
        atemp[2] += xi_pow2;

        // 计算右侧向量b
        double yi = y[i];
        b[0] += yi;
        b[1] += yi * xi;
        b[2] += yi * xi_pow2;
    }

    // 构建法方程矩阵
    double a[3][3];
    a[0][0] = atemp[0];
    a[0][1] = atemp[1];
    a[0][2] = atemp[2];
    a[1][0] = atemp[1];
    a[1][1] = atemp[2];
    a[1][2] = 0;
    a[2][0] = atemp[2];
    a[2][1] = 0;
    a[2][2] = 0;

    // 高斯列主元消元法
    for (k = 0; k < 2; k++) { // 消去第k列
        // 寻找主元行
        int max_row = k;
        double max_val = fabs(a[k][k]);
        for (i = k + 1; i < 3; i++) {
            if (fabs(a[i][k]) > max_val) {
                max_val = fabs(a[i][k]);
                max_row = i;
            }
        }

        // 交换行
        if (max_row != k) {
            for (j = k; j < 3; j++) {
                double temp = a[k][j];
                a[k][j] = a[max_row][j];
                a[max_row][j] = temp;
            }
            double temp_b = b[k];
            b[k] = b[max_row];
            b[max_row] = temp_b;
        }

        // 消元
        for (i = k + 1; i < 3; i++) {
            double factor = a[i][k] / a[k][k];
            for (j = k; j < 3; j++) {
                a[i][j] -= factor * a[k][j];
            }
            b[i] -= factor * b[k];
        }
    }

    // 回代求解
    coeff[2] = b[2] / a[2][2];
    for (i = 1; i >= 0; i--) {
        double sum = 0.0;
        for (j = i + 1; j < 3; j++) {
            sum += a[i][j] * coeff[j];
        }
        coeff[i] = (b[i] - sum) / a[i][i];
    }
}