JUCE/modules/juce_gui_basics/native/accessibility/juce_win32_UIAHelpers.h

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

   This file is part of the JUCE library.
   Copyright (c) 2022 - Raw Material Software Limited

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 7 End-User License
   Agreement and JUCE Privacy Policy.

   End User License Agreement: www.juce.com/juce-7-licence
   Privacy Policy: www.juce.com/juce-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

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

namespace juce
{

namespace VariantHelpers
{
    namespace Detail
    {
        template <typename Fn, typename ValueType>
        inline VARIANT getWithValueGeneric (Fn&& setter, ValueType value)
        {
            VARIANT result{};
            setter (value, &result);
            return result;
        }
    }

    inline void clear (VARIANT* variant)
    {
        variant->vt = VT_EMPTY;
    }

    inline void setInt (int value, VARIANT* variant)
    {
        variant->vt   = VT_I4;
        variant->lVal = value;
    }

    inline void setBool (bool value, VARIANT* variant)
    {
        variant->vt      = VT_BOOL;
        variant->boolVal = value ? -1 : 0;
    }

    inline void setString (const String& value, VARIANT* variant)
    {
        variant->vt      = VT_BSTR;
        variant->bstrVal = SysAllocString ((const OLECHAR*) value.toWideCharPointer());
    }

    inline void setDouble (double value, VARIANT* variant)
    {
        variant->vt     = VT_R8;
        variant->dblVal = value;
    }

    inline VARIANT getWithValue (double value)        { return Detail::getWithValueGeneric (&setDouble, value); }
    inline VARIANT getWithValue (const String& value) { return Detail::getWithValueGeneric (&setString, value); }
}

inline JUCE_COMRESULT addHandlersToArray (const std::vector<const AccessibilityHandler*>& handlers, SAFEARRAY** pRetVal)
{
    auto numHandlers = handlers.size();

    *pRetVal = SafeArrayCreateVector (VT_UNKNOWN, 0, (ULONG) numHandlers);

    if (pRetVal != nullptr)
    {
        for (LONG i = 0; i < (LONG) numHandlers; ++i)
        {
            auto* handler = handlers[(size_t) i];

            if (handler == nullptr)
                continue;

            ComSmartPtr<IRawElementProviderSimple> provider;
            JUCE_BEGIN_IGNORE_WARNINGS_GCC_LIKE ("-Wlanguage-extension-token")
            handler->getNativeImplementation()->QueryInterface (IID_PPV_ARGS (provider.resetAndGetPointerAddress()));
            JUCE_END_IGNORE_WARNINGS_GCC_LIKE

            auto hr = SafeArrayPutElement (*pRetVal, &i, provider);

            if (FAILED (hr))
                return E_FAIL;
        }
    }

    return S_OK;
}

template <typename Value, typename Object, typename Callback>
inline JUCE_COMRESULT withCheckedComArgs (Value* pRetVal, Object& handle, Callback&& callback)
{
    if (pRetVal == nullptr)
        return E_INVALIDARG;

    *pRetVal = Value{};

    if (! handle.isElementValid())
        return (HRESULT) UIA_E_ELEMENTNOTAVAILABLE;

    return callback();
}

} // namespace juce