// Copyright (c) 2021, Viktor Larsson
// All rights reserved.
//
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// modification, are permitted provided that the following conditions are met:
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#pragma once

#include "PoseLib/camera_pose.h"
#include "PoseLib/robust/sampling.h"
#include "PoseLib/robust/utils.h"
#include "PoseLib/types.h"

namespace poselib {

class HomographyEstimator {
  public:
    HomographyEstimator(const HomographyOptions &opt, const std::vector<Point2D> &points2D_1,
                        const std::vector<Point2D> &points2D_2)
        : num_data(points2D_1.size()), opt(opt), x1(points2D_1), x2(points2D_2),
          sampler(num_data, sample_sz, opt.ransac) {
        x1s.resize(sample_sz);
        x2s.resize(sample_sz);
        sample.resize(sample_sz);
    }

    void generate_models(std::vector<Eigen::Matrix3d> *models);
    double score_model(const Eigen::Matrix3d &H, size_t *inlier_count) const;
    void refine_model(Eigen::Matrix3d *H) const;

    const size_t sample_sz = 4;
    const size_t num_data;

  private:
    const HomographyOptions &opt;
    const std::vector<Point2D> &x1;
    const std::vector<Point2D> &x2;

    RandomSampler sampler;
    // pre-allocated vectors for sampling
    std::vector<Eigen::Vector3d> x1s, x2s;
    std::vector<size_t> sample;
};

} // namespace poselib