satdump/plugins/cubesat_support/spino/module_spino_decoder.cpp

#include "module_spino_decoder.h"
#include "common/codings/crc/crc_generic.h"
#include "common/utils.h"
#include "imgui/imgui.h"
#include "logger.h"
#include <cstdint>

#define BUFFER_SIZE 256

namespace spino
{
    SpinoDecoderModule::SpinoDecoderModule(std::string input_file, std::string output_file_hint, nlohmann::json parameters)
        : satdump::pipeline::base::FileStreamToFileStreamModule(input_file, output_file_hint, parameters)
    {
        input_buffer = new int8_t[BUFFER_SIZE];
        fsfsm_file_ext = ".frm";
    }

    SpinoDecoderModule::~SpinoDecoderModule() { delete[] input_buffer; }

    void SpinoDecoderModule::process()
    {

        std::string directory = d_output_file_hint.substr(0, d_output_file_hint.rfind('/')) + "/";

        uint8_t bits_buf[BUFFER_SIZE];

        // Deframer
        const uint32_t d_syncword = 0x2EFC9827;
        uint32_t def_shifter = 0;
        bool def_in_frame = false;
        int def_bitn = 0;
        uint8_t def_bytshift = 0;
        std::vector<uint8_t> wip_frame;

        codings::crc::GenericCRC crc_ccitt(16, 0x1021, 0x0000, 0x0000, false, false);

        while (should_run())
        {
            // Read buffer
            read_data((uint8_t *)input_buffer, BUFFER_SIZE);

            // Slice
            for (int i = 0; i < BUFFER_SIZE; i++)
                bits_buf[i] = input_buffer[i] > 0;

            // Deframe

            for (int ibit = 0; ibit < BUFFER_SIZE; ibit++)
            {
                uint8_t bit = bits_buf[ibit];
                def_shifter = def_shifter << 1 | bit;

                if (def_in_frame)
                {
                    def_bytshift = def_bytshift << 1 | bit;
                    def_bitn++;

                    if (def_bitn == 8)
                    {
                        wip_frame.push_back(def_bytshift);
                        def_bitn = 0;
                    }

                    // Here we should have a full Spino header
                    if (wip_frame.size() >= 18)
                    {
                        int size = wip_frame[17] << 8 | wip_frame[16];

                        if ((int)wip_frame.size() >= size + 16)
                        {
                            // CRC Check
                            uint64_t crc = wip_frame[wip_frame.size() - 1] << 8 | wip_frame[wip_frame.size() - 2];
                            if (crc == crc_ccitt.compute(wip_frame.data(), wip_frame.size() - 2))
                            {
                                uint16_t pkt_sz = wip_frame.size();
                                uint8_t buffer_sz[6];
                                buffer_sz[0] = 0x1a;
                                buffer_sz[1] = 0xcf;
                                buffer_sz[2] = 0xfc;
                                buffer_sz[3] = 0x1d;
                                buffer_sz[4] = pkt_sz >> 8;
                                buffer_sz[5] = pkt_sz & 0xFF;

                                wip_frame.insert(wip_frame.begin(), buffer_sz, buffer_sz + 6);
                                write_data((uint8_t *)wip_frame.data(), wip_frame.size());
                                logger->info(size);
                                frm_cnt++;
                            }

                            def_in_frame = false;
                        }
                    }

                    continue;
                }

                if (def_shifter == d_syncword)
                {
                    def_in_frame = true;
                    def_bitn = 0;
                    wip_frame.clear();
                }
            }
        }

        logger->info("Decoding finished");

        cleanup();
    }

    nlohmann::json SpinoDecoderModule::getModuleStats()
    {
        auto v = satdump::pipeline::base::FileStreamToFileStreamModule::getModuleStats();
        v["frm_cnt"] = frm_cnt;
        return v;
    }

    void SpinoDecoderModule::drawUI(bool window)
    {
        ImGui::Begin("Spino Decoder", NULL, window ? 0 : NOWINDOW_FLAGS);

        ImGui::Button("Deframer", {200 * ui_scale, 20 * ui_scale});
        {
            ImGui::Text("Frames : ");
            ImGui::SameLine();
            ImGui::TextColored(style::theme.green, UITO_C_STR(frm_cnt));
        }

        drawProgressBar();

        ImGui::End();
    }

    std::string SpinoDecoderModule::getID() { return "spino_decoder"; }

    std::shared_ptr<satdump::pipeline::ProcessingModule> SpinoDecoderModule::getInstance(std::string input_file, std::string output_file_hint, nlohmann::json parameters)
    {
        return std::make_shared<SpinoDecoderModule>(input_file, output_file_hint, parameters);
    }
} // namespace spino