Cast.h

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/** @noop License Comment
 *  @file
 *  @copyright
 *  This Source Code is subject to the terms of the Mozilla Public License, v2.0.
 *  If a copy of the MPL was not distributed with this file You can obtain one at
 *  https://mozilla.org/MPL/2.0/
 *  
 *  @author David Mórász
 *  @date 2025
 */
 
#pragma once
 
#include "CoreMinimal.h"
#include "McroWindows/Error/WindowsError.h"
#include "Microsoft/COMPointer.h"
 
namespace Mcro::Windows::COM
{
    using namespace Mcro::Windows::Error;
    
    template <typename From, typename To>
    FCanFail ComCast(From* from, TComPtr<To>& to, bool fastError = false)
    {
        HRESULT hr = from->QueryInterface(IID_PPV_ARGS(&to));
        if (UNLIKELY(hr != S_OK))
            return IError::Make(new FHresultError(hr, fastError))
                ->AsRecoverable()
                ->WithMessageF(
                    TEXT("Object of type %s did not implement %s"),
                    *TTypeString<From>,
                    *TTypeString<To>
                );
        return Success();
    }
    
    template <typename From, typename To>
    FCanFail ComCast(TComPtr<From> const& from, TComPtr<To>& to, bool fastError = false)
    {
        return ComCast(from.Get(), to, fastError);
    }
    
    template <typename From, typename To>
    TMaybe<TComPtr<To>> ComCast(From* from, bool fastError = false)
    {
        TComPtr<To> to;
        ComCast(from, to, fastError);
        return MoveTemp(to);
    }
    
    template <typename From, typename To>
    TMaybe<TComPtr<To>> ComCast(TComPtr<From> const& from, bool fastError = false)
    {
        return ComCast(from.Get(), fastError);
    }
}