// SPDX-FileCopyrightText: 2026 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#pragma once

#include <vector>
#include <cstdint>
#include <cstddef>

class ImagePreprocessorBuffer {
protected:
    std::vector<int32_t> buffer;
public:
    explicit ImagePreprocessorBuffer(size_t npixels);
    virtual ~ImagePreprocessorBuffer() = default;

    // Standard CPU operation
    std::vector<int32_t> &getBuffer();
    const std::vector<int32_t> &getBuffer() const;
    int32_t &operator[](size_t i);
    const int32_t &operator[](size_t i) const;
    size_t size() const;

    int32_t *data();
    const int32_t *data() const;

    // GPU operations (overriden in ImagePreprocessorBufferGPU
    virtual int32_t *getGPUBuffer();
    virtual const int32_t *getGPUBuffer() const;

    // Values of the pixels with the given flat indices. Not just operator[] in a loop: on the GPU the
    // preprocessed image can live in device memory only, and then this gathers them there.
    virtual void Gather(const std::vector<uint32_t> &npixel, std::vector<int32_t> &values) const;
};