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

#pragma once

#include <string>
#include <vector>

#include "JFJochReader.h"
#include "XTC.h"

// Reads serial-crystallography stills straight from LCLS-I XTC files: one camera image per event,
// from a single-panel detector such as the Rayonix CCDs at MFX and XPP. A multi-panel detector
// (CSPAD, ePix, JUNGFRAU at LCLS) is stored as raw per-module data with its own calibration, and is
// not read here.
//
// XTC records the events and not the experiment: there is no distance, beam centre or wavelength
// in it that this reader can use. Those come from a DIALS experiment list (.expt) beside the XTC
// files, or in their parent directory - the geometry a deposition ships for cctbx.xfel, and what
// cctbx.xfel itself reads them with. Without one the run is refused rather than guessed.
//
// The images are stills: no goniometer. Each is decoded on demand. The pixels are passed on as
// stored - the CCD's constant offset of a few counts is left in, as it is in an SMV image, and the
// pre-scan finds the defective pixels.
class JFJochXTCReader : public JFJochReader {
    std::vector<xtc::Frame> frames_;
    std::shared_ptr<JFJochReaderDataset> dataset_;

    bool LoadImage_i(std::shared_ptr<JFJochReaderDataset> &dataset,
                     DataMessage &message,
                     std::vector<uint8_t> &buffer,
                     int64_t image_number,
                     bool update_dataset) override;

    template <class Buffer>
    CompressedImage DecodeInto(int64_t image_number, Buffer &buffer, std::vector<uint8_t> &scratch) const;

    void ReadGeometry(const std::string &expt);

public:
    ~JFJochXTCReader() override = default;

    static bool CanRead(const std::string &path);

    // path is one XTC stream, or a directory whose streams are all read.
    void ReadFiles(const std::string &path);

    [[nodiscard]] uint64_t GetNumberOfImages() const override;
    void Close() override;

    bool ReadRawImage(int64_t image_number, JFJochReaderRawImage &image) override;
    [[nodiscard]] std::vector<SpotToSave> ReadSpots(int64_t image) const override;
};