Jungfraujoch/image_analysis/scale_merge/ScaleOnTheFly.h

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

#pragma once

#include "HKLKey.h"
#include "Merge.h"
#include "../../common/DiffractionExperiment.h"
#include "../IntegrationOutcome.h"

#include <map>


struct ScaleOnTheFlyResult {
    double B = 0;
    double G = 1.0;
    double cc = NAN;
    size_t cc_n = 0;
    float time_s = 0.0;
    bool succesful = false;
};

// Per-image reference scaling with the FIXED partiality model: each reflection's stored partiality is
// used as-is (it is 1 for stills and the zeta/erf rocking-curve value already set at prediction for
// rotation data). No partiality recompute, no mosaicity or wedge refinement. The B-factor may be refined
// (Ceres); otherwise the fit is linear in G (a robust 1-D IRLS). Rotation self-scaling/merging offline
// uses the dedicated RotationScaleMerge path instead.
class ScaleOnTheFly {
    constexpr static size_t MIN_REFLECTIONS = 20;

    const ScalingSettings s;
    const HKLKeyGenerator hkl_key_generator;
    std::map<HKLKey, double> reference_data;

    bool Accept(const Reflection &r) const;
    [[nodiscard]] std::pair<double, size_t> CalculateGlobalCC(const std::vector<Reflection> &reflections) const;
public:
    ScaleOnTheFly(const DiffractionExperiment &x, const std::vector<MergedReflection> &ref);

    void Scale(IntegrationOutcome &integration_outcome) const;
    void Scale(std::vector<IntegrationOutcome> &integration_outcome, size_t nthreads = 0) const;
};