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

#include "ImagePreprocessor.h"

ImagePreprocessor::ImagePreprocessor(const DiffractionExperiment &experiment,
                                     const PixelMask &mask)
    : npixels(experiment.GetPixelsNum()),
      experiment(experiment),
      mask_1bit(npixels, false),
      saturation_limit(experiment.GetSaturationLimit()) {

    for (int i = 0; i < npixels; i++)
        mask_1bit[i] = (mask.GetMask().at(i) != 0);
}

ImageStatistics ImagePreprocessor::Analyze(std::vector<int32_t> &processed_image, const uint8_t *image_ptr, CompressedImageMode image_mode) {
    switch (image_mode) {
        case CompressedImageMode::Int8:
            return Analyze<int8_t>(processed_image, image_ptr, INT8_MIN, INT8_MAX);
        case CompressedImageMode::Int16:
            return Analyze<int16_t>(processed_image, image_ptr, INT16_MIN, INT16_MAX);
        case CompressedImageMode::Int32:
            return Analyze<int32_t>(processed_image, image_ptr, INT32_MIN, INT32_MAX);
        case CompressedImageMode::Uint8:
            return Analyze<uint8_t>(processed_image, image_ptr, UINT8_MAX, UINT8_MAX);
        case CompressedImageMode::Uint16:
            return Analyze<uint16_t>(processed_image, image_ptr, UINT16_MAX, UINT16_MAX);
        case CompressedImageMode::Uint32:
            return Analyze<uint32_t>(processed_image, image_ptr, UINT32_MAX, UINT32_MAX);
        default:
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, "RGB/float mode not supported");
    }
}

template<class T>
ImageStatistics ImagePreprocessor::Analyze(std::vector<int32_t> &processed_image, const uint8_t *input, T err_pixel_val, T sat_pixel_val) {

    if (processed_image.size() != npixels)
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, "Processed image size mismatch");

    auto image = reinterpret_cast<const T *>(input);

    ImageStatistics ret{};

    if (sat_pixel_val > saturation_limit)
        sat_pixel_val = static_cast<T>(saturation_limit);

    for (int i = 0; i < npixels; i++) {
        if (mask_1bit[i] != 0) {
            processed_image[i] = INT32_MIN;
            ++ret.masked_pixel_count;
        } else if (image[i] >= sat_pixel_val) {
            processed_image[i] = INT32_MAX;
            ++ret.saturated_pixel_count;
        } else if (std::is_signed<T>::value && (image[i] == err_pixel_val)) {
            // Error pixels are possible only for signed types
            processed_image[i] = INT32_MIN;
            ++ret.error_pixel_count;
        } else {
            processed_image[i] = static_cast<int32_t>(image[i]);
            if (image[i] > ret.max_value)
                ret.max_value = image[i];
            if (image[i] < ret.min_value)
                ret.min_value = image[i];
        }
    }
    return ret;
}