/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2016 - ROLI Ltd.

   Permission is granted to use this software under the terms of the ISC license
   http://www.isc.org/downloads/software-support-policy/isc-license/

   Permission to use, copy, modify, and/or distribute this software for any
   purpose with or without fee is hereby granted, provided that the above
   copyright notice and this permission notice appear in all copies.

   THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH REGARD
   TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
   FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT,
   OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF
   USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
   TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
   OF THIS SOFTWARE.

   -----------------------------------------------------------------------------

   To release a closed-source product which uses other parts of JUCE not
   licensed under the ISC terms, commercial licenses are available: visit
   www.juce.com for more information.

  ==============================================================================
*/

#ifndef JUCE_WIN32_COMSMARTPTR_H_INCLUDED
#define JUCE_WIN32_COMSMARTPTR_H_INCLUDED

#if JUCE_MINGW || (! (defined (_MSC_VER) || defined (__uuidof)))
#ifdef __uuidof
 #undef __uuidof
#endif

template<typename Type> struct UUIDGetter { static CLSID get() { jassertfalse; return CLSID(); } };
#define __uuidof(x)  UUIDGetter<x>::get()

 template <>
 struct UUIDGetter<::IUnknown>
 {
     static CLSID get()
     {
       GUID g = { 0, 0, 0, { 0xc0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46 } };
       return g;
     }
 };
#endif

inline GUID uuidFromString (const char* const s) noexcept
{
    unsigned long p0;
    unsigned int p1, p2, p3, p4, p5, p6, p7, p8, p9, p10;

  #ifndef _MSC_VER
    sscanf
  #else
    sscanf_s
  #endif
        (s, "%08lX-%04X-%04X-%02X%02X-%02X%02X%02X%02X%02X%02X",
              &p0, &p1, &p2, &p3, &p4, &p5, &p6, &p7, &p8, &p9, &p10);

    GUID g = { p0, (uint16) p1, (uint16) p2, { (uint8) p3, (uint8) p4, (uint8) p5, (uint8) p6,
                                               (uint8) p7, (uint8) p8, (uint8) p9, (uint8) p10 }};
    return g;
}

//==============================================================================
/** A simple COM smart pointer.
*/
template <class ComClass>
class ComSmartPtr
{
public:
    ComSmartPtr() throw() : p (0)                                  {}
    ComSmartPtr (ComClass* const obj) : p (obj)                    { if (p) p->AddRef(); }
    ComSmartPtr (const ComSmartPtr<ComClass>& other) : p (other.p) { if (p) p->AddRef(); }
    ~ComSmartPtr()                                                 { release(); }

    operator ComClass*() const throw()     { return p; }
    ComClass& operator*() const throw()    { return *p; }
    ComClass* operator->() const throw()   { return p; }

    ComSmartPtr& operator= (ComClass* const newP)
    {
        if (newP != 0)  newP->AddRef();
        release();
        p = newP;
        return *this;
    }

    ComSmartPtr& operator= (const ComSmartPtr<ComClass>& newP)  { return operator= (newP.p); }

    // Releases and nullifies this pointer and returns its address
    ComClass** resetAndGetPointerAddress()
    {
        release();
        p = 0;
        return &p;
    }

    HRESULT CoCreateInstance (REFCLSID classUUID, DWORD dwClsContext = CLSCTX_INPROC_SERVER)
    {
        HRESULT hr = ::CoCreateInstance (classUUID, 0, dwClsContext, __uuidof (ComClass), (void**) resetAndGetPointerAddress());
        jassert (hr != CO_E_NOTINITIALIZED); // You haven't called CoInitialize for the current thread!
        return hr;
    }

    template <class OtherComClass>
    HRESULT QueryInterface (REFCLSID classUUID, ComSmartPtr<OtherComClass>& destObject) const
    {
        if (p == 0)
            return E_POINTER;

        return p->QueryInterface (classUUID, (void**) destObject.resetAndGetPointerAddress());
    }

    template <class OtherComClass>
    HRESULT QueryInterface (ComSmartPtr<OtherComClass>& destObject) const
    {
        return this->QueryInterface (__uuidof (OtherComClass), destObject);
    }

private:
    ComClass* p;

    void release()  { if (p != 0) p->Release(); }

    ComClass** operator&() throw(); // private to avoid it being used accidentally
};

//==============================================================================
#define JUCE_COMRESULT  HRESULT __stdcall

//==============================================================================
template <class ComClass>
class ComBaseClassHelperBase   : public ComClass
{
public:
    ComBaseClassHelperBase (unsigned int initialRefCount)  : refCount (initialRefCount) {}
    virtual ~ComBaseClassHelperBase() {}

    ULONG __stdcall AddRef()    { return ++refCount; }
    ULONG __stdcall Release()   { const ULONG r = --refCount; if (r == 0) delete this; return r; }

protected:
    ULONG refCount;

    JUCE_COMRESULT QueryInterface (REFIID refId, void** result)
    {
        if (refId == __uuidof (IUnknown))
            return castToType <IUnknown> (result);

        *result = 0;
        return E_NOINTERFACE;
    }

    template <class Type>
    JUCE_COMRESULT castToType (void** result)
    {
        this->AddRef(); *result = dynamic_cast<Type*> (this); return S_OK;
    }
};

/** Handy base class for writing COM objects, providing ref-counting and a basic QueryInterface method.
*/
template <class ComClass>
class ComBaseClassHelper   : public ComBaseClassHelperBase <ComClass>
{
public:
    ComBaseClassHelper (unsigned int initialRefCount = 1) : ComBaseClassHelperBase <ComClass> (initialRefCount) {}
    ~ComBaseClassHelper() {}

    JUCE_COMRESULT QueryInterface (REFIID refId, void** result)
    {
        if (refId == __uuidof (ComClass))
            return this->template castToType <ComClass> (result);

        return ComBaseClassHelperBase <ComClass>::QueryInterface (refId, result);
    }
};

#endif   // JUCE_WIN32_COMSMARTPTR_H_INCLUDED
