MultiMC5/launcher/QObjectPtr.h

#pragma once

#include <functional>
#include <memory>
#include <QObject>

namespace details
{
struct DeleteQObjectLater
{
    void operator()(QObject *obj) const
    {
        obj->deleteLater();
    }
};
}
/**
 * A unique pointer class with unique pointer semantics intended for derivates of QObject
 * Calls deleteLater() instead of destroying the contained object immediately
 */
template<typename T> using unique_qobject_ptr = std::unique_ptr<T, details::DeleteQObjectLater>;

/**
 * A shared pointer class with shared pointer semantics intended for derivates of QObject
 * Calls deleteLater() instead of destroying the contained object immediately
 */
template <typename T>
class shared_qobject_ptr
{
public:
    shared_qobject_ptr(){}
    shared_qobject_ptr(T * wrap)
    {
        reset(wrap);
    }
    shared_qobject_ptr(const shared_qobject_ptr<T>& other)
    {
        m_ptr = other.m_ptr;
    }
    template<typename Derived>
    shared_qobject_ptr(const shared_qobject_ptr<Derived> &other)
    {
        m_ptr = other.unwrap();
    }

public:
    void reset(T * wrap)
    {
        using namespace std::placeholders;
        m_ptr.reset(wrap, std::bind(&QObject::deleteLater, _1));
    }
    void reset(const shared_qobject_ptr<T> &other)
    {
        m_ptr = other.m_ptr;
    }
    void reset()
    {
        m_ptr.reset();
    }
    T * get() const
    {
        return m_ptr.get();
    }
    T * operator->() const
    {
        return m_ptr.get();
    }
    T & operator*() const
    {
        return *m_ptr.get();
    }
    operator bool() const
    {
        return m_ptr.get() != nullptr;
    }
    const std::shared_ptr <T> unwrap() const
    {
        return m_ptr;
    }

private:
    std::shared_ptr <T> m_ptr;
};