ComPtr.h

#ifndef NEO_COMPTR_H
#define NEO_COMPTR_H

namespace neo
{

template<typename T>
class ComPtr
{
public:
    ComPtr()
        : _ptr(nullptr)
    {}
    
    ComPtr(T* p)
        : _ptr(p)
    {}
    
    // copy ctor
    ComPtr(const ComPtr<T>& other)
        : _ptr(other._ptr)
    {
        _ptr->AddRef();
    }
    
    // assignment operator
    ComPtr& operator= (const ComPtr& other)
    {
        _ptr = other._ptr;
        _ptr->AddRef();
        return *this;
    }
    
    // move ctor
    ComPtr(ComPtr&& other)
    {
        _ptr = other._ptr;
        other._ptr = nullptr;
    }
    
    // move operator
    ComPtr& operator= (ComPtr&& other)
    {
        if(this != &other)
        {
            _ptr = other._ptr;
            other._ptr = nullptr;
        }
        return *this;
    }
    
    ~ComPtr()
    {
        if(_ptr)
            _ptr->Release();
    }

    void Release()
    {
        if(_ptr)
            _ptr->Release();
        _ptr = nullptr;
    }

    T** PtrPtr()
    {
        Release();
        return &_ptr;
    }

    operator T* () const { return _ptr; }
    T* operator -> () const { return _ptr; }
    T& operator * () const { return *_ptr; }
private:
    T* _ptr;
};

} // namespace neo

#endif