// Example program
#include <iostream>
#include <string>
#include <vector>
#include <algorithm>
#include <memory>

struct IDisposableObserver;

struct IObservable
{
  virtual void add(IDisposableObserver* observer) = 0;
  virtual void remove(IDisposableObserver* observer) = 0;
};

struct IDisposableObserver
{
    IObservable* obs;
    IDisposableObserver(IObservable* o) : obs(o) {}

    virtual void notify() = 0;

    virtual ~IDisposableObserver()
    {
        std::cout << "~IDisposableObserver(): Dispose observer" << std::endl;

        obs->remove(this);
    }
};

struct Endpoint : public IDisposableObserver
{
    Endpoint(const std::string& ldn, IObservable* obs) : IDisposableObserver(obs)
    {
        obs->add(this);
    }

    virtual void notify()
    {
        std::cout << "Notify " << std::endl;
    }
};

struct Server
{
    std::vector<std::unique_ptr<Endpoint>> endpoints;
    void publishEndpoint(const std::string& ldn, IObservable* observable)
    {
        auto endpoint = std::make_unique<Endpoint>(ldn, observable);
        endpoints.push_back(std::move(endpoint));
    }
};


struct Fru : public IObservable
{
    std::vector<IDisposableObserver*> observers;

    void add(IDisposableObserver* observer) override
    {
        auto it = std::find_if(observers.begin(), observers.end(), [&](const IDisposableObserver* ptr) { return ptr == observer; } );

        if (it != observers.end())
        {
            return;
        }

        observers.push_back(observer);
    }

    void remove(IDisposableObserver* observer) override
    {
        auto it = std::find_if(observers.begin(), observers.end(), [&](const IDisposableObserver* ptr) { return ptr == observer; } );

        if (it != observers.end())
        {
            return;
        }

        observers.erase(it);
    }

    void doIt()
    {
        for (const auto& x : observers)
        {
            x->notify();
        }
    }
};




int main()
{
    Fru fru{};

    {
    Server usi{};
    usi.publishEndpoint("ldn=1", &fru);
    }


    fru.doIt();
}