language_name_winrt.cpp

#include "pch.h"

#include "framework.h"

#include "utils_winrt.h"

#include "utils.h"

#include <windows.globalization.h>
#include <objidlbase.h>
#include <roapi.h>

std::string GetLanguageNameWinRT(const std::string& languageTag)
{
    HSTRING_HEADER namespaceStringHeader;
    HSTRING namespaceString = nullptr;
    HRESULT hr = S_OK;

    hr = RoInitialize(RO_INIT_MULTITHREADED);
    if (FAILED(hr))
        return {};

    const std::wstring languageClassName = RuntimeClass_Windows_Globalization_Language;
    hr = WindowsCreateStringReference(languageClassName.c_str(),
        (UINT32)languageClassName.length(),
        &namespaceStringHeader,
        &namespaceString);

    if (FAILED(hr) || !namespaceString)
        return {};

    ABI::Windows::Globalization::ILanguageFactory* languageFactory = nullptr; // __x_ABI_CWindows_CGlobalization_CILanguageFactory
    const IID& languageFactoryIID = ABI::Windows::Globalization::IID_ILanguageFactory; // IID___x_ABI_CWindows_CGlobalization_CILanguageFactory

    hr = RoGetActivationFactory(namespaceString, languageFactoryIID, (void**)&languageFactory);

    if (FAILED(hr))
        return {};

    std::wstring languageTagWide(utf8::widen(languageTag));
    HSTRING_HEADER languageTagStringHeader;
    HSTRING languageTagString;

    hr = WindowsCreateStringReference(languageTagWide.c_str(),
        (UINT32)languageTagWide.size(),
        &languageTagStringHeader,
        &languageTagString);

    if (FAILED(hr))
    {
        languageFactory->Release();
        return {};
    }

    ABI::Windows::Globalization::ILanguage* language = nullptr; // __x_ABI_CWindows_CGlobalization_CILanguage

    hr = languageFactory->CreateLanguage(languageTagString, &language);

    if (FAILED(hr))
    {
        languageFactory->Release();
        return {};
    }

    HSTRING languageDisplayNameString = nullptr;
    hr = language->get_DisplayName(&languageDisplayNameString);

    if (FAILED(hr))
    {
        language->Release();
        languageFactory->Release();
        return {};
    }

    std::wstring returnString = WindowsGetStringRawBuffer(languageDisplayNameString, NULL);

    hr = WindowsDeleteString(languageDisplayNameString);
    language->Release();
    languageFactory->Release();

    return utf8::narrow(returnString);
}