/**
*
*  @file message_bus.hpp
*  @author zxw
*  Copyright 2024, yjrobotics.  All rights reserved.
*
*  robotics
*
*/
#pragma once
//stl
#include <map>
#include <any>
#include <string>
#include <functional>
//boost
#include <boost/noncopyable.hpp>
//robotics
#include "function_traits.hpp"
#include "message_bus_impl.h"

namespace robotics {
	namespace v3 {
		class message_bus :boost::noncopyable {
		public:
			/**
			 * @brief 构造
			 */
			message_bus() {
				message_bus_impl_ = message_bus_impl::instance();
			}
			/**
			 * @brief 析构
			 */
			~message_bus() {
			}
			/**
			 * @brief 注册消息
			 * @tparam _Fn 
			 * @param str_topic 
			 * @param observer 观察者
			 * @param f 
			 * @return 
			 */
			template<typename _Fn>
			bool bind(const std::string& str_topic, bool observer, _Fn&& f) {
				auto func = v3::to_function(std::forward<_Fn>(f));
				return add(str_topic, observer, std::move(func));
			}
			/**
			 * @brief 注册消息
			 * @tparam _Fn 
			 * @tparam _Obj 
			 * @param str_topic 
			 * @param observer 观察者
			 * @param f 
			 * @param obj 
			 * @return 
			 */
			template<typename _Fn, typename _Obj>
			bool bind(const std::string& str_topic, bool observer, _Fn&& f, _Obj&& obj) {
				auto func = v3::to_function((v3::function_traits<_Fn>::stl_function_type)(std::bind_front(std::forward<_Fn>(f), std::forward<_Obj>(obj))));
				return add(str_topic, observer, std::move(func));
			}
			/**
			 * @brief 发送消息
			 * @param str_topic
			 */
			template<typename _Ret,bool _BCast = false>
			_Ret invoke(const std::string& str_topic) {
				using function_type = std::function<_Ret()>;
				std::string str_msg_type = str_topic + typeid(function_type).name();
				auto funcs = message_bus_impl_->find(str_msg_type);
				if constexpr (!_BCast) {
					if (std::find_if(funcs.begin(), funcs.end(), [](auto it) {return !it.first; }) == funcs.end()) {
						throw std::runtime_error("no function binded to topic " + str_topic);
					}
				}
				if constexpr (std::is_same<_Ret, void>::value) {
					for (auto& fn : funcs) {
						std::any_cast<function_type>(fn.second)();
					}
				}
				else {
					_Ret result = _Ret{};
					for (auto& fn : funcs) {
						if (!fn.first) {
							result = std::any_cast<function_type>(fn.second)();
						}
						else {
							std::any_cast<function_type>(fn.second)();
						}
					}
					return result;
				}
			}
			/**
			 * @brief 发送消息
			 * @tparam ..._Args
			 * @param str_topic
			 * @param ...args
			 */
			template<typename _Ret, bool _BCast = false,typename... _Args>
			_Ret invoke(const std::string& str_topic, _Args ...args) {
				using function_type = std::function<_Ret(_Args...)>;
				std::string str_msg_type = str_topic + typeid(function_type).name();
				auto funcs = message_bus_impl_->find(str_msg_type);
				if constexpr (!_BCast) {
					if (std::find_if(funcs.begin(), funcs.end(), [](auto it) {return !it.first; }) == funcs.end()) {
						throw std::runtime_error("no function binded to topic " + str_topic);
					}
				}
				if constexpr(std::is_same<_Ret, void>::value) {
					for(auto &fn : funcs) {
						std::any_cast<function_type>(fn.second)(args...);
					}
				}
				else {
					_Ret result = _Ret{};
					for (auto& fn : funcs) {
						if (!fn.first) {
							result = std::any_cast<function_type>(fn.second)(args...);
						}
						else {
							std::any_cast<function_type>(fn.second)(args...);
						}
					}
					return result;
				}
			}
			/**
			 * @brief 移除某个主题，需要主题和消息类型
			 * @tparam ...Args
			 * @param strTopic
			 */
			template<typename..._Args>
			void remove(const std::string& str_topic) {
				using function_type = std::function<void(_Args...)>;
				std::string str_msg_type = str_topic + typeid(function_type).name();
				message_bus_impl_->remove(str_msg_type);
			}
		private:
			/**
			 * @brief 单个添加
			 * @tparam _Fn 
			 * @param str_topic 
			 * @param f 
			 * @return 
			 */
			template<typename _Fn>
			bool add(const std::string& str_topic, bool observer, _Fn&& f) {
				std::string str_msg_type = str_topic + typeid(f).name();
				return message_bus_impl_->bind(str_msg_type, observer, std::forward<_Fn>(f));
			}
		private:
			message_bus_impl* message_bus_impl_ = nullptr;
		};
	}
}