#ifndef SENSORDEVICESPEC_H
#define SENSORDEVICESPEC_H

#include <vector>
#include <string>
#include <iostream>
#include <sstream>
#include <algorithm>
#include <iterator>
#include <stdexcept>

namespace smo {
namespace device {

/* Carrier used by the DAP spec parser to pass one parenthesized segment
 * (e.g. postrin(interest-pc=85) or pcloudLightAmbience(...)) up the reduction
 * stack; the spec_body reduction classifies segments and populates the
 * DeviceAttachmentSpec. Defined here so both the parser header and consumers
 * of the generated header see the type.
 */
struct DapSegment
{
    std::string name;
    std::vector<std::pair<std::string, std::string>> params;
};

class DeviceAttachmentSpec
{
public:
    friend std::ostream& operator<<(
        std::ostream& os, const DeviceAttachmentSpec& spec)
    {
        os << spec.stringify();
        return os;
    }

    bool operator==(const DeviceAttachmentSpec& other) const
    {
        return deviceIdentifier == other.deviceIdentifier &&
               sensorType == other.sensorType &&
               postrin == other.postrin &&
               negtrin == other.negtrin &&
               qualeIfaceApi == other.qualeIfaceApi &&
               stimBuffApi == other.stimBuffApi &&
               provider == other.provider &&
               deviceSelector == other.deviceSelector;
    }

public:
    std::string deviceIdentifier;
    char sensorType;
    /* postrin/negtrin hold the literal segment name ("postrin" /
     * "negtrin") when present, empty string when the DAP spec omits the
     * corresponding intrin specifier. Params vectors carry the params from
     * within the postrin(...)/negtrin(...) segment.
     */
    std::string postrin;
    std::vector<std::pair<std::string,std::string>> postrinParams;
    std::string negtrin;
    std::vector<std::pair<std::string,std::string>> negtrinParams;
    std::string qualeIfaceApi;
    std::vector<std::pair<std::string,std::string>> qualeIfaceApiParams;
    std::string stimBuffApi;
    std::vector<std::pair<std::string,std::string>> stimBuffApiParams;
    std::string provider;
    std::vector<std::pair<std::string,std::string>> providerParams;
    std::string deviceSelector;

    static void stringifyParams(
        std::ostream& os,
        const std::vector<std::pair<std::string,std::string>>& params)
    {
        for (const auto& param : params)
        {
            os << param.first;
            if (!param.second.empty()) {
                os << "=" << param.second;
            }
            os << " ";
        }
    }

    std::string stringify() const
    {
        std::ostringstream os;
        os << "Device Identifier: " << deviceIdentifier
            << ", Sensor Type: " << sensorType;

        if (!postrin.empty())
        {
            os << ", Postrin Params: (";
            stringifyParams(os, postrinParams);
            os << ")";
        }
        if (!negtrin.empty())
        {
            os << ", Negtrin Params: (";
            stringifyParams(os, negtrinParams);
            os << ")";
        }

        os << ", QualeIface API: " << qualeIfaceApi << ", QualeIface API Params: (";
        for (const auto& param : qualeIfaceApiParams)
        {
            os << param.first;
            if (!param.second.empty()) {
                os << "=" << param.second;
            }
            os << " ";
        }
        os << "), StimBuff API: " << stimBuffApi
            << ", StimBuff API Params: (";
        for (const auto& param : stimBuffApiParams)
        {
            os << param.first;
            if (!param.second.empty()) {
                os << "=" << param.second;
            }
            os << " ";
        }
        os << "), Provider: " << provider << ", Provider Params: (";
        for (const auto& param : providerParams)
        {
            os << param.first;
            if (!param.second.empty()) {
                os << "=" << param.second;
            }
            os << " ";
        }
        os << "), Device Selector: " << deviceSelector;

        return os.str();
    }

    /**
     * @brief Parse a required integer parameter from a parameter list
     * @param params The parameter vector to search in
     * @param paramName The name of the parameter to parse
     * @return The parsed integer value
     * @throws std::runtime_error if parameter is not found or cannot be parsed
     */
    static int parseRequiredParamAsInt(
		const std::vector<std::pair<std::string,std::string>>& params,
		const std::string& paramName
		)
    {
        auto it = std::find_if(
            params.begin(),
            params.end(),
            [&paramName](const auto& param) {
                return param.first == paramName;
            }
        );

        if (it == params.end())
        {
            throw std::runtime_error(
                "No " + paramName + " specified in params");
        }

        try {
            return std::stoi(it->second);
        } catch (const std::exception& e) {
            throw std::runtime_error(
                "Failed to parse '" + paramName + "' param value '"
                + it->second + "' as integer: " + e.what());
        }
    }

    /**
     * @brief Parse an optional integer parameter from a parameter list
     * @param params The parameter vector to search in
     * @param paramName The name of the parameter to parse
     * @param defaultValue The default value to return if no parameter is found
     * @return The parsed integer value, or defaultValue if none found
     * @note The lattermost supplied matching param wins if multiple are present
     */
    static int parseOptionalParamAsInt(
		const std::vector<std::pair<std::string,std::string>>& params,
		const std::string& paramName,
		int defaultValue
		)
    {
        const std::string paramNames[] = {paramName};
        return parseOptionalParamAsIntWithSynonyms(
            params, paramNames, defaultValue);
    }

    /**
     * @brief Parse an optional integer parameter from a parameter list using synonyms
     * @param params The parameter vector to search in
     * @param synonymNames The collection of synonymous parameter names to try
     * @param defaultValue The default value to return if no parameter is found
     * @return The parsed integer value, or defaultValue if none found
     * @note The lattermost supplied matching param wins if multiple are present
     */
    template <typename SynonymCollectionT>
    static int parseOptionalParamAsIntWithSynonyms(
		const std::vector<std::pair<std::string,std::string>>& params,
		const SynonymCollectionT& synonymNames,
		int defaultValue
		)
    {
        // Loop through params in reverse order; lattermost supplied param wins.
        for (auto paramIt = params.rbegin(); paramIt != params.rend(); ++paramIt)
        {
            const auto& [paramName, paramValue] = *paramIt;
            auto synonymIt = std::find(
                std::begin(synonymNames), std::end(synonymNames), paramName);

			if (synonymIt == std::end(synonymNames))
				{ continue; }

            try {
                return std::stoi(paramValue);
            } catch (const std::exception& e) {
                throw std::runtime_error(
                    "Failed to parse '" + paramName + "' param value '"
                    + paramValue + "' as integer: " + e.what());
            }
        }

        return defaultValue;
    }
};

class InteroceptorDevAttachmentSpec : public DeviceAttachmentSpec
{
};

class ExtrospectorDevAttachmentSpec : public DeviceAttachmentSpec
{
};

} // namespace device
} // namespace smo

#endif // SENSORDEVICESPEC_H