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

#ifndef JFJOCH_ROTATIONINDEXER_H
#define JFJOCH_ROTATIONINDEXER_H

#include <vector>
#include <mutex>

#include "../common/DiffractionSpot.h"
#include "../common/DiffractionExperiment.h"
#include "indexing/IndexerThreadPool.h"
#include "lattice_search/LatticeSearch.h"

// RotationIndexer works as following:
// 1. First accumulates spot results from rotation images (only images within a certain stride are included)
// 2. When a minimum number of images is reached (at least 10 images AND at least 10 deg), indexing is attempted
// 3. If indexing is successful - lattice is provided that is used by subsequent images
// 4. If indexing is not-successful - accumulation procedure is continued

struct RotationIndexerResult {
    CrystalLattice lattice;
    LatticeSearchResult search_result;
    DiffractionGeometry geom;
};

class RotationIndexer {
    mutable std::mutex m;
    const DiffractionExperiment& experiment;

    constexpr static int64_t max_spots = 10000;
    constexpr static int64_t min_images_for_indexing = 10;

    const bool index_ice_rings;
    bool indexing_tried = false;

    std::vector<SpotToSave> v_;
    std::vector<Coord> coords_;
    std::optional<GoniometerAxis> axis_;
    const DiffractionGeometry geom_;
    DiffractionGeometry updated_geom_;
    LatticeSearchResult search_result_;

    IndexerThreadPool &indexer_;

    int64_t last_accumulated_image = -1;
    int64_t accumulated_images = 0;

    int64_t image_stride;
    int64_t first_image_to_try_indexing;

    std::optional<CrystalLattice> indexed_lattice;

    void TryIndex();
public:
    RotationIndexer(const DiffractionExperiment& x, IndexerThreadPool& indexer);
    void SetLattice(const CrystalLattice &lattice);
    std::optional<RotationIndexerResult> ProcessImage(int64_t image, const std::vector<SpotToSave>& spots);
    std::optional<RotationIndexerResult> GetLattice();
};

#endif //JFJOCH_ROTATIONINDEXER_H