// Copyright (2019-2023) Paul Scherrer Institute

#include "JFJochBrokerParser.h"
#include "JFJochBroker.h"

inline bool CHECK_ARRAY(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (!j[tag].is_array())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be array");
        return true;
    } else
        return false;
}

inline bool CHECK_OBJECT(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (!j[tag].is_object())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be object");
        return true;
    } else
        return false;
}

inline int64_t GET_I64(const nlohmann::json &j, const std::string& tag, int64_t def) {
    if (j.contains(tag)) {
        if (!j[tag].is_number_integer())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be integer");
        try {
            return j[tag].get<int64_t>();
        } catch (std::exception &e) {
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + ": " + e.what());
        }
    } else
        return def;
}

inline bool GET_BOOL(const nlohmann::json &j, const std::string& tag, bool def) {
    if (j.contains(tag)) {
        if (!j[tag].is_boolean())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be integer");
        try {
        return j[tag].get<bool>();
        } catch (std::exception &e) {
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + ": " + e.what());
        }
    } else
        return def;
}

inline std::string GET_STR(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (!j[tag].is_string())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be string");
        try {
        return j[tag].get<std::string>();
        } catch (std::exception &e) {
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + ": " + e.what());
        }
    } else
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " is compulsory");
}

inline int64_t GET_I64(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (!j[tag].is_number_integer())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be integer");
        try {
        return j[tag].get<int64_t>();
        } catch (std::exception &e) {
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + ": " + e.what());
        }
    } else
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " is compulsory");
}

inline std::vector<std::string> GET_STR_ARR(const nlohmann::json &j, const std::string& tag) {
    std::vector<std::string> ret;

    if (CHECK_ARRAY(j, tag)) {
        try {
            for (const auto &iter: j[tag])
                ret.push_back(iter.get<std::string>());
        } catch (std::exception &e) {
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + ": " + e.what());
        }
    }
    return ret;
}

DetectorModuleGeometry::Direction GET_DIRECTION(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (!j[tag].is_string())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be string");
        if (j[tag] == "Xp")
            return DetectorModuleGeometry::Direction::Xpos;
        if (j[tag] == "Xn")
            return DetectorModuleGeometry::Direction::Xneg;
        if (j[tag] == "Yp")
            return DetectorModuleGeometry::Direction::Ypos;
        if (j[tag] == "Yn")
            return DetectorModuleGeometry::Direction::Yneg;
        else
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
                                  "Allowed values for direction: Xp, Xn, Yp, Yn");
    } else
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " is compulsory");
}

inline int64_t TimeToUs(const std::string &unit) {
    if ((unit == "us") || unit.empty()) return 1L;
    else if (unit == "ms") return 1000L;
    else if ((unit == "s") || (unit == "sec")) return 1000*1000L;
    else
        throw JFJochException(JFJochExceptionCategory::WrongUnit,
                              "Only us, ms and s (or sec) are viable units for time");
}

inline std::chrono::microseconds GET_TIME(const nlohmann::json &j, const std::string& tag) {
    if (j.contains(tag)) {
        if (j[tag].is_number())
            return std::chrono::microseconds (std::lround(j[tag].get<double>() * 1000.0 * 1000.0));
        else if (j[tag].is_string()) {
            std::string::size_type pos;
            auto text = j[tag].get<std::string>();

            // Check if floating point
            pos = text.find_first_of('.');
            if (pos != std::string::npos)
                throw JFJochException(JFJochExceptionCategory::WrongNumber,
                                      "Time must be provided as <integer> {s|ms|us|Hz} - no floating point allowed");

            // Convert integer part
            int64_t val = std::stol(text, &pos);
            if (pos == 0)
                throw JFJochException(JFJochExceptionCategory::WrongNumber,
                                      "Time must be provided as <integer> {s|ms|us|Hz}");

            pos = text.find_first_not_of(' ', pos);
            if (pos != std::string::npos) {
                if (text.substr(pos) == "Hz")
                    val = 1000*1000L / val;
                else
                    val *= TimeToUs(text.substr(pos));
            }
            return std::chrono::microseconds(val);
        } else
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " must be number in seconds or string with time units s|ms|us");
    } else
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, tag + " is compulsory");
}

DetectorGeometry ParseStandardDetectorGeometry(const nlohmann::json &j) {
    int32_t nmodules   = GET_I64(j, "nmodules");
    int32_t gap_x      = GET_I64(j, "gap_x", 8);
    int32_t gap_y      = GET_I64(j, "gap_y", 36);
    int32_t h_stacking = GET_I64(j, "horizontal_stacking", 2);
    bool mirror_y      = GET_BOOL(j, "mirror_y", true);
    return {nmodules, h_stacking, gap_x, gap_y, mirror_y};
}

DetectorGeometry ParseCustomDetectorGeometry(const nlohmann::json &j) {
    std::vector<DetectorModuleGeometry> modules;
    for (const auto &iter: j) {
        if (!iter.is_object())
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
                                  "custom_geometry element must be JSON object");
        int64_t x0 = GET_I64(iter, "x0");
        int64_t y0 = GET_I64(iter, "y0");
        auto fast = GET_DIRECTION(iter, "fast_axis");
        auto slow = GET_DIRECTION(iter, "slow_axis");
        modules.emplace_back(x0, y0, fast, slow);
    }
    return {modules};
}

DetectorGeometry ParseDetectorGeometry(const nlohmann::json &j) {
    if (CHECK_OBJECT(j, "standard_geometry"))
        return ParseStandardDetectorGeometry(j["standard_geometry"]);
    else if (CHECK_ARRAY(j, "custom_geometry"))
        return ParseCustomDetectorGeometry(j["custom_geometry"]);
    else
        throw JFJochException(JFJochExceptionCategory::InputParameterInvalid,
                              "It is compulsory to have either standard_detector or custom_detector declared.");
}

DetectorSetup ParseDetectorSetup(const nlohmann::json &j) {
    if (!j.is_object())
        throw JFJochException(JFJochExceptionCategory::JSON, "Expecting JSON object for detector setup");

    DetectorGeometry geom = ParseDetectorGeometry(j);

    std::string description = GET_STR(j, "description");
    auto module_hostname = GET_STR_ARR(j, "module_hostname");
    auto gain_files = GET_STR_ARR(j, "gain_files");

    DetectorSetup setup(geom, description, module_hostname);
    if (!gain_files.empty())
        setup.LoadGain(gain_files);

    setup.UDPInterfaceCount(GET_I64(j, "udp_interface_count", 2));
    return setup;
}

void ParseDetectorSetup(const nlohmann::json &j, const std::string& tag, JFJochBroker& broker) {
    if (CHECK_ARRAY(j, tag)) {
        for (const auto &iter : j[tag])
            broker.AddDetectorSetup(ParseDetectorSetup(iter));
    } else
        throw JFJochException(JFJochExceptionCategory::JSON, "Detector setup not found");
}

void ParseFacilityConfiguration(const nlohmann::json &input, const std::string& tag, DiffractionExperiment &experiment) {
    if (CHECK_OBJECT(input, tag)) {
        auto j = input[tag];
        experiment.SourceName(GET_STR(j, "source_name"));
        experiment.SourceNameShort(GET_STR(j, "source_name_short"));
        experiment.InstrumentName(GET_STR(j, "instrument_name"));
        experiment.InstrumentNameShort(GET_STR(j, "instrument_name_short"));
        experiment.DataStreams(GET_I64(j, "datastreams"));

        experiment.PedestalG0Frames(GET_I64(j, "pedestal_g0_frames"));
        experiment.PedestalG1Frames(GET_I64(j, "pedestal_g1_frames"));
        experiment.PedestalG2Frames(GET_I64(j, "pedestal_g2_frames"));

        experiment.FrameTime(GET_TIME(j, "frame_time_us"), GET_TIME(j, "count_time_us"));

        experiment.SpotFindingPeriod(GET_TIME(j, "spot_finding_period_us"));
        experiment.PreviewPeriod(GET_TIME(j, "preview_period_us"));

        experiment.IPv4BaseAddr(GET_STR(j, "detector_ipv4"));
    } else
        throw JFJochException(JFJochExceptionCategory::JSON, "Default configuration not found");
}

void ParseBrokerConfiguration(const nlohmann::json &input, const std::string& tag, JFJochBroker& broker) {
    if (CHECK_OBJECT(input, tag)) {
        auto j = input[tag];
        if (j.contains("receiver_addr"))
            broker.Services().Receiver(GET_STR(j, "receiver_addr"));

        if (CHECK_ARRAY(j, "writer")) {
            for (const auto &iter: j["writer"]) {
                broker.Services().Writer(GET_STR(iter, "addr_grpc"), GET_STR(iter, "addr_zmq"));
            }
        }

        if (j.contains("detector_addr"))
            broker.Services().Detector(GET_STR(j, "detector_addr"));
    } else
        throw JFJochException(JFJochExceptionCategory::JSON, "Service configuration not found");
}