Jungfraujoch/common/Reflection.h

// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#pragma once

#include <cstdint>
#include <optional>
#include <cmath>

#include "SpotToSave.h"

struct Reflection {
    int32_t h;
    int32_t k;
    int32_t l;
    float image_number; // Can be in-between for 3D integration
    float delta_phi_deg; // phi angle from XDS - difference from middle of current frame (NOT an absolute angle)
    float predicted_x;
    float predicted_y;
    float observed_x;
    float observed_y;
    float d;
    float I;
    float bkg;
    float var_bkg;        // non-signal (background) part of sigma^2, carried to the merge
    float sigma;
    float dist_ewald;
    float rlp;
    float partiality;     // fraction of the reflection recorded in the sampled (rocking) slice
    float zeta;
    float image_scale_corr; // I_true = scaling_correction * I; scaling_correction = rlp / (partiality * image_scale)
    bool observed = false;
    bool on_ice_ring = false; // sits on a hexagonal-ice powder ring: excluded from scaling, kept for merging
};

struct MergedReflection {
    int32_t h = 0;
    int32_t k = 0;
    int32_t l = 0;
    float I = NAN;
    float sigma = NAN;
    float I_half[2] = {NAN, NAN};
    float sigma_half[2] = {NAN, NAN};
    float d = 0.0;
    bool rfree_flag = false;
    float F = NAN;       // French-Wilson amplitude |F| (filled by ApplyFrenchWilson at end of merge)
    float sigmaF = NAN;  // its sigma
    // Anomalous (Bijvoet) split of this reflection's own observations, kept even when the merge is
    // Friedel-averaged (I above is the Friedel mean). Lets I(+)/I(-) be written and CCano reported by
    // default without scaling anomalously; NaN when a hand was not measured or for centrics.
    float I_plus = NAN;
    float sigma_plus = NAN;
    float I_minus = NAN;
    float sigma_minus = NAN;
    // French-Wilson amplitudes of the two hands (filled by ApplyFrenchWilson from I_plus/I_minus).
    float F_plus = NAN;
    float sigmaF_plus = NAN;
    float F_minus = NAN;
    float sigmaF_minus = NAN;
};