#pragma once

#include "../color/ColorGradingParams.h"

#include <opencv2/core.hpp>

#include <cstdint>
#include <optional>
#include <string>

namespace photoconv {

/**
 * @brief Film type classification for processing decisions.
 */
enum class FilmType {
    Unknown,
    ColorNegative,   // C-41 process
    BWNegative,      // B&W negative
    ColorPositive,   // Slide / E-6
    BWPositive,      // B&W positive
};

/**
 * @brief RAW metadata extracted from the image file.
 *
 * Populated by the Loader stage and carried through the pipeline
 * for use by downstream stages (e.g., color correction using WB data).
 */
struct RawMetadata {
    std::string camera_make;       // e.g. "Sony", "Canon", "Nikon"
    std::string camera_model;      // e.g. "ILCE-7M3"
    float iso_speed{0.0f};
    float shutter_speed{0.0f};     // seconds
    float aperture{0.0f};          // f-number
    float focal_length{0.0f};      // mm
    float wb_red{1.0f};            // White balance multipliers
    float wb_green{1.0f};
    float wb_blue{1.0f};
    int raw_width{0};
    int raw_height{0};
    int raw_bit_depth{0};          // Bits per channel in source
    std::string timestamp;         // ISO 8601
};

/**
 * @brief Core data structure flowing through the entire pipeline.
 *
 * Every pipeline stage receives an ImageData, transforms it, and
 * returns a new ImageData (or Error) via std::expected.
 *
 * Invariants:
 * - rgb is always CV_16UC3 (16-bit, 3-channel BGR)
 * - metadata is populated after the Loader stage
 * - film_type is set after the Detect stage
 */
struct ImageData {
    cv::Mat rgb;                              // 16-bit BGR (CV_16UC3)
    std::string source_path;                  // Original file path
    RawMetadata metadata;                     // Camera/RAW metadata
    FilmType film_type{FilmType::Unknown};    // Detected after Detect stage
    std::optional<cv::Rect> crop_region;      // Set by Crop stage
    ColorGradingParams color_params{};        // User-defined color grading overrides
};

} // namespace photoconv