#include "stretchpanel.h"
#include <QVBoxLayout>
#include "imageringlist.h"
#include <QDebug>

StretchPanel::StretchPanel(QWidget *parent) : QWidget(parent)
{
    QVBoxLayout *layout = new QVBoxLayout(this);
    setLayout(layout);

    m_lowSlider = new QSlider(Qt::Horizontal, this);
    m_highSlider = new QSlider(Qt::Horizontal, this);
    m_paramSlider = new QSlider(Qt::Horizontal, this);

    m_lowSlider->setRange(0, UINT16_MAX);
    m_lowSlider->setPageStep(512);
    m_highSlider->setRange(0, UINT16_MAX);
    m_highSlider->setPageStep(512);
    m_highSlider->setValue(UINT16_MAX);
    m_paramSlider->setRange(0, UINT16_MAX);
    m_paramSlider->setPageStep(512);

    m_stretchSelect = new QComboBox(this);
    m_stretchSelect->addItems({tr("Linear"), tr("Square root"), tr("Power"), tr("Logarithm"), tr("Asinh")});

    layout->addWidget(m_lowSlider);
    layout->addWidget(m_highSlider);
    layout->addWidget(m_paramSlider);
    layout->addWidget(m_stretchSelect);

    connect(m_lowSlider, SIGNAL(valueChanged(int)), this, SIGNAL(lowChanged(int)));
    connect(m_highSlider, SIGNAL(valueChanged(int)), this, SIGNAL(highChanged(int)));
    connect(m_paramSlider, SIGNAL(valueChanged(int)), this, SLOT(calculateParam()));
    connect(m_stretchSelect, SIGNAL(activated(int)), this, SIGNAL(stretchChanged(int)));
    connect(m_stretchSelect, SIGNAL(activated(int)), this, SLOT(calculateParam()));
}

void StretchPanel::imageLoaded(Image *img)
{
    if(img)
    {
        if(img->rawImage())
        {
            double mean, stdDev, median;
            img->rawImage()->imageStats(&mean, &stdDev, &median, nullptr, nullptr);
            double mad = img->rawImage()->MAD();
            float l = median - mad;
            m_lowSlider->setValue(l);
            float p = std::log(0.25)/std::log(mean/UINT16_MAX);
            m_paramSlider->setValue(p * UINT16_MAX);
            qDebug() << "Low" << l << p;
        }
    }
}

void StretchPanel::calculateParam()
{
    float val = m_paramSlider->value();
    float param;
    switch(m_stretchSelect->currentIndex())
    {
    case 2:
        param = val/UINT16_MAX;
        param = 1.0f / (param * 5.0f + 1);
        break;
    case 3:
        param = val;
        break;
    case 4:
        param = 1.0f/std::max(0.00001f, 1.0f-(val/UINT16_MAX));
        //val += 100;
        //param = val/100.0f;
        break;
    default:
        return;
    }
    emit paramChanged(param);
}