//
// Created by YY on 2023/3/30.
//

#ifndef MYAPPLICATION3_OBSERVER_H
#define MYAPPLICATION3_OBSERVER_H

#include <iostream>
#include <string>
#include <functional>
#include <map>

namespace ilovers {
    class NonCopyable {
    protected:
        NonCopyable() = default;

        ~NonCopyable() = default;

        NonCopyable(const NonCopyable &) = delete;

        NonCopyable &operator=(const NonCopyable &) = delete;
    };

    template<typename Func>
    class Observer : NonCopyable {
    public:
        Observer() {}

        ~Observer() {}

        int Connect(Func &&f) {
            return Assgin(f);
        }

        int Connect(const Func &f) {
            return Assgin(f);
        }

        void Disconnect(int key) {
            m_connections.erase(key);
        }

        template<typename... Args>
        void Notify(Args &&... args) {
            for (auto &it: m_connections) {
                it.second(std::forward<Args>(args)...);
            }
        }

    private:
        template<typename F>
        int Assgin(F &&f) {
            int k = m_observerId++;
            m_connections.emplace(k, std::forward<F>(f));
            return k;
        }

        int m_observerId = 0;
        std::map<int, Func> m_connections;
    };
}

#endif //MYAPPLICATION3_OBSERVER_H