#include "nmVolumeSliceSettings.h"
#include "nmVolumeData.h"
#include <QCoreApplication>
#include <cmath>
#include <vtkMath.h>

nmVolumeSliceSettings::nmVolumeSliceSettings()
    : m_bShowPlane(true), m_bShowSource(false)
{
    for(int nAxis = 0; nAxis < 3; ++nAxis) {
        m_dOrigin[nAxis] = 0.0;
        m_dNormal[nAxis] = nAxis == 2 ? 1.0 : 0.0;
    }
}

nmVolumeSliceSettings nmVolumeSliceSettings::fromData(const nmVolumeData& oData)
{
    nmVolumeSliceSettings oSettings;
    double dBounds[6];
    oData.getBounds(dBounds);
    for(int nAxis = 0; nAxis < 3; ++nAxis) {
        // 避免两个同号大坐标相加溢出。
        oSettings.m_dOrigin[nAxis] = dBounds[2 * nAxis] * 0.5 + dBounds[2 * nAxis + 1] * 0.5;
    }
    oSettings.m_sPropertyId = oData.getInitialPropertyId();
    return oSettings;
}

bool nmVolumeSliceSettings::normalize(QString* pError)
{
    if(pError != nullptr) pError->clear();
    double dMaximum = 0.0;
    for(int nAxis = 0; nAxis < 3; ++nAxis) {
        if(!vtkMath::IsFinite(m_dOrigin[nAxis]) || !vtkMath::IsFinite(m_dNormal[nAxis])) {
            if(pError != nullptr) *pError = QCoreApplication::translate("nmVolumeSliceSettings", "Origin and normal must contain finite numbers.");
            return false;
        }
        dMaximum = qMax(dMaximum, std::fabs(m_dNormal[nAxis]));
    }
    if(dMaximum == 0.0) {
        if(pError != nullptr) *pError = QCoreApplication::translate("nmVolumeSliceSettings", "The plane normal must not be zero.");
        return false;
    }
    // 先缩放再求模，兼容科学计数法输入的极大、极小非零法向。
    double dNormal[3];
    double dLengthSquared = 0.0;
    for(int nAxis = 0; nAxis < 3; ++nAxis) {
        dNormal[nAxis] = m_dNormal[nAxis] / dMaximum;
        dLengthSquared += dNormal[nAxis] * dNormal[nAxis];
    }
    const double dLength = std::sqrt(dLengthSquared);
    for(int nAxis = 0; nAxis < 3; ++nAxis) m_dNormal[nAxis] = dNormal[nAxis] / dLength;
    return true;
}