#include <iostream>
#include <vector>
#include <string>
#include "Service.h"
#include "thrawn_api.h"
#include "spdlog/spdlog.h" 
#include "Cache.h"
#include "LuaEngine.h"
#include <filesystem>
#include "Version.h"
#include <cstring>
#include <thread>
#include "mqtt++.h"

std::vector<std::string> lua_scripts_in_folder(const std::string& path_str) {
	std::vector<std::string> scripts;

	std::filesystem::path scripts_folder(path_str);
	
	if (std::filesystem::exists(scripts_folder)) {
		for (const auto& file: std::filesystem::directory_iterator(scripts_folder)) {
			if (file.is_regular_file() && file.path().extension() == ".lua") {
				scripts.push_back(file.path().string());
			}
		}
	}else{
		throw std::invalid_argument("Folder '" + path_str + "' does not exist.");
	}

	return scripts;
}

int main(int argc, char* argv[]) {
	std::string services_path_str = "/etc/thrawn";
	std::string mqttServerURI = "tcp://chimaera:1883";
	mqttpp::LastWill last_will {"dev/thrawn/status", "0"};
	std::string version_topic = "dev/thrawn/version";

	std::string version_topic_value = std::to_string(THRAWN_MAJOR_VERSION) + "." + std::to_string(THRAWN_MINOR_VERSION) + "." + std::to_string(THRAWN_PATCH_VERSION);
	std::string lastWillConnected = "1";


	/*
	* Parsing arguments
	* Show version or load path
	*/
	if (argc > 1) {
		if (strcmp(argv[1], "-v") == 0 || strcmp(argv[1], "--version") == 0) {
			std::cout << "Version: " << THRAWN_MAJOR_VERSION << "." << THRAWN_MINOR_VERSION << "." << THRAWN_PATCH_VERSION << std::endl;

			return 0;
		}

		services_path_str = argv[1];
	}
	
	/*
	 * MQTT
	 */
	spdlog::info("Starting MQTT connection to '{}' .", mqttServerURI);

	mqttpp::Client mqtt(mqttServerURI, last_will);

	if (! mqtt.connect()) {
		spdlog::error("Failed to establishe mqtt connection to ‘{}'", mqttServerURI);

		return 1;
	}

	mqtt.publish(last_will.topic, lastWillConnected);
	mqtt.publish(version_topic, version_topic_value);
	mqtt.subscribe("#", [&] (const char* topic, const std::string& msg) {
		LuaEngine::get_instance().cache.set_topic_value(topic, msg);

		for (auto& service : LuaEngine::get_instance().services) {
			for (const std::string& sub_topic : service.subscriptions) {
				if (sub_topic == topic) {
					service.on_update(TopicState(topic, msg));
				}
			}
		}
	});

	LuaEngine::get_instance().publish = [&](const TopicState& state) {
		mqtt.publish(state.topic, state.value);
	};

	spdlog::info("Connection to MQTT server '{}' successfull.", mqttServerURI);

	try {
		for (const auto& script : lua_scripts_in_folder(services_path_str)) {
			LuaEngine::get_instance().create_service(script);
		}
	}catch(const std::exception& e) {
		spdlog::error(e.what());

		return 1;
	}

	/*
	 * LUA Engine
	 */
	spdlog::info("Starting Thrawn services on Chimaera.");

	LuaEngine::get_instance().load_services();

	spdlog::info("{} service(s) loaded.", LuaEngine::get_instance().services.size());
	
	LuaEngine::get_instance().start_services();

	spdlog::info("All services loaded.");

	while (true) {
		using namespace std::chrono_literals;
		std::this_thread::sleep_for(100ms);
	}

	return 0;
}