// SPDX-FileCopyrightText: 2024 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#include <cmath>

#include "AzimuthalIntegrationSettings.h"
#include "JFJochException.h"

#define check_max(param, val, max) if ((val) > (max)) throw JFJochException(JFJochExceptionCategory::InputParameterAboveMax, param)
#define check_min(param, val, min) if ((val) < (min)) throw JFJochException(JFJochExceptionCategory::InputParameterBelowMin, param)
#define check_finite(param, val) if (!std::isfinite(val)) throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, param)

AzimuthalIntegrationSettings::AzimuthalIntegrationSettings() {
    UpdateBinCount();
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::SolidAngleCorrection(bool input) {
    solid_angle_correction = input;
    return *this;
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::QRange_recipA(float low, float high) {
    check_finite("Low Q for azimuthal integration", low);
    check_finite("High Q for azimuthal integration", high);
    check_max("High Q for azimuthal integration", high, 10.0);
    check_min("Low Q for azimuthal integration", low, 0.001);
    if (high <= low)
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
                              "High Q must be higher than low Q");

    high_q_recipA = high;
    low_q_recipA = low;
    UpdateBinCount();
    return *this;
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::QSpacing_recipA(float input) {
    check_finite("Q spacing for azimuthal integration", input);
    check_min("Q spacing for azimuthal integration", input, 0.00999);
    q_spacing = input;
    UpdateBinCount();
    return *this;
}

bool AzimuthalIntegrationSettings::IsSolidAngleCorrection() const {
    return solid_angle_correction;
}

float AzimuthalIntegrationSettings::GetHighQ_recipA() const {
    return high_q_recipA;
}

float AzimuthalIntegrationSettings::GetLowQ_recipA() const {
    return low_q_recipA;
}

float AzimuthalIntegrationSettings::GetQSpacing_recipA() const {
    return q_spacing;
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::BkgEstimateQRange_recipA(float low, float high) {
    check_finite("Low Q for azimuthal integration", low);
    check_finite("High Q for azimuthal integration", high);
    check_max("High Q for azimuthal integration", high, 10.0);
    check_min("Low Q for azimuthal integration", low, 0.001);
    if (high <= low)
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
                              "High Q must be higher than low Q");

    bkg_estimate_low_q_recipA = low;
    bkg_estimate_high_q_recipA = high;

    return *this;
}

float AzimuthalIntegrationSettings::GetBkgEstimateLowQ_recipA() const {
    return bkg_estimate_low_q_recipA;
}

float AzimuthalIntegrationSettings::GetBkgEstimateHighQ_recipA() const {
    return bkg_estimate_high_q_recipA;
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::PolarizationCorrection(bool input) {
    polarization_correction = input;
    return *this;
}

bool AzimuthalIntegrationSettings::IsPolarizationCorrection() const {
    return polarization_correction;
}

AzimuthalIntegrationSettings &AzimuthalIntegrationSettings::AzimuthalBinCount(int32_t input) {
    check_min("Azimuthal bin count", input, 1);
    check_max("Azimuthal bin count", input, 512);
    azim_bins = input;
    UpdateBinCount();
    return *this;
}

int32_t AzimuthalIntegrationSettings::GetQBinCount() const {
    return q_bins;
}

int32_t AzimuthalIntegrationSettings::GetAzimuthalBinCount() const {
    return azim_bins;
}

int32_t AzimuthalIntegrationSettings::GetBinCount() const {
    return total_bins;
}

uint16_t AzimuthalIntegrationSettings::QToBin(float q) const {
    return std::min<uint16_t>(GetBinCount() - 1, std::floor(std::max(0.0f, (q - GetLowQ_recipA()) / GetQSpacing_recipA())));
}

uint16_t AzimuthalIntegrationSettings::GetBin(float q, float phi_deg) const {
    if (q < low_q_recipA || q >= high_q_recipA)
        return UINT16_MAX;
    if (phi_deg < 0.0 || phi_deg >= 360)
        return UINT16_MAX;

    int16_t q_bin = std::floor((q - low_q_recipA) / q_spacing);
    int16_t phi_bin = std::floor(phi_deg / 360.0f * azim_bins);
    return q_bin + phi_bin * GetQBinCount();
}

void AzimuthalIntegrationSettings::UpdateBinCount() {
    q_bins = std::ceil((high_q_recipA - low_q_recipA) / q_spacing);
    total_bins = q_bins * azim_bins;
}