HRESULT GetTransformedFileName()

in src/modules/powerrename/lib/Helpers.cpp [45:235]
184 lines of code
51 McCabe index (conditional complexity)

HRESULT GetTransformedFileName(_Out_ PWSTR result, UINT cchMax, _In_ PCWSTR source, DWORD flags, bool isFolder)
{
    std::locale::global(std::locale(""));
    HRESULT hr = E_INVALIDARG;
    if (source && flags)
    {
        if (flags & Uppercase)
        {
            if (isFolder)
            {
                hr = StringCchCopy(result, cchMax, source);
                if (SUCCEEDED(hr))
                {
                    std::transform(result, result + wcslen(result), result, ::towupper);
                }
            }
            else
            {
                if (flags & NameOnly)
                {
                    std::wstring stem = fs::path(source).stem().wstring();
                    std::transform(stem.begin(), stem.end(), stem.begin(), ::towupper);
                    hr = StringCchPrintf(result, cchMax, L"%s%s", stem.c_str(), fs::path(source).extension().c_str());
                }
                else if (flags & ExtensionOnly)
                {
                    std::wstring extension = fs::path(source).extension().wstring();
                    if (!extension.empty())
                    {
                        std::transform(extension.begin(), extension.end(), extension.begin(), ::towupper);
                        hr = StringCchPrintf(result, cchMax, L"%s%s", fs::path(source).stem().c_str(), extension.c_str());
                    }
                    else
                    {
                        hr = StringCchCopy(result, cchMax, source);
                        if (SUCCEEDED(hr))
                        {
                            std::transform(result, result + wcslen(result), result, ::towupper);
                        }
                    }
                }
                else
                {
                    hr = StringCchCopy(result, cchMax, source);
                    if (SUCCEEDED(hr))
                    {
                        std::transform(result, result + wcslen(result), result, ::towupper);
                    }
                }
            }
        }
        else if (flags & Lowercase)
        {
            if (isFolder)
            {
                hr = StringCchCopy(result, cchMax, source);
                if (SUCCEEDED(hr))
                {
                    std::transform(result, result + wcslen(result), result, ::towlower);
                }
            }
            else
            {
                if (flags & NameOnly)
                {
                    std::wstring stem = fs::path(source).stem().wstring();
                    std::transform(stem.begin(), stem.end(), stem.begin(), ::towlower);
                    hr = StringCchPrintf(result, cchMax, L"%s%s", stem.c_str(), fs::path(source).extension().c_str());
                }
                else if (flags & ExtensionOnly)
                {
                    std::wstring extension = fs::path(source).extension().wstring();
                    if (!extension.empty())
                    {
                        std::transform(extension.begin(), extension.end(), extension.begin(), ::towlower);
                        hr = StringCchPrintf(result, cchMax, L"%s%s", fs::path(source).stem().c_str(), extension.c_str());
                    }
                    else
                    {
                        hr = StringCchCopy(result, cchMax, source);
                        if (SUCCEEDED(hr))
                        {
                            std::transform(result, result + wcslen(result), result, ::towlower);
                        }
                    }
                }
                else
                {
                    hr = StringCchCopy(result, cchMax, source);
                    if (SUCCEEDED(hr))
                    {
                        std::transform(result, result + wcslen(result), result, ::towlower);
                    }
                }
            }
        }
        else if (flags & Titlecase)
        {
            if (!(flags & ExtensionOnly))
            {
                std::vector<std::wstring> exceptions = { L"a", L"an", L"to", L"the", L"at", L"by", L"for", L"in", L"of", L"on", L"up", L"and", L"as", L"but", L"or", L"nor" };
                std::wstring stem = isFolder ? source : fs::path(source).stem().wstring();
                std::wstring extension = isFolder ? L"" : fs::path(source).extension().wstring();

                size_t stemLength = stem.length();
                bool isFirstWord = true;

                while (stemLength > 0 && (iswspace(stem[stemLength - 1]) || iswpunct(stem[stemLength - 1])))
                {
                    stemLength--;
                }

                for (size_t i = 0; i < stemLength; i++)
                {
                    if (!i || iswspace(stem[i - 1]) || iswpunct(stem[i - 1]))
                    {
                        if (iswspace(stem[i]) || iswpunct(stem[i]))
                        {
                            continue;
                        }
                        size_t wordLength = 0;
                        while (i + wordLength < stemLength && !iswspace(stem[i + wordLength]) && !iswpunct(stem[i + wordLength]))
                        {
                            wordLength++;
                        }
                        if (isFirstWord || i + wordLength == stemLength || std::find(exceptions.begin(), exceptions.end(), stem.substr(i, wordLength)) == exceptions.end())
                        {
                            stem[i] = towupper(stem[i]);
                            isFirstWord = false;
                        }
                        else
                        {
                            stem[i] = towlower(stem[i]);
                        }
                    }
                    else
                    {
                        stem[i] = towlower(stem[i]);
                    }
                }
                hr = StringCchPrintf(result, cchMax, L"%s%s", stem.c_str(), extension.c_str());
            }
            else
            {
                hr = StringCchCopy(result, cchMax, source);
            }
        } 
        else if (flags & Capitalized)
        {
            if (!(flags & ExtensionOnly))
            {
                std::wstring stem = isFolder ? source : fs::path(source).stem().wstring();
                std::wstring extension = isFolder ? L"" : fs::path(source).extension().wstring();

                size_t stemLength = stem.length();

                while (stemLength > 0 && (iswspace(stem[stemLength - 1]) || iswpunct(stem[stemLength - 1])))
                {
                    stemLength--;
                }

                for (size_t i = 0; i < stemLength; i++)
                {
                    if (!i || iswspace(stem[i - 1]) || iswpunct(stem[i - 1]))
                    {
                        if (iswspace(stem[i]) || iswpunct(stem[i]))
                        {
                            continue;
                        }
                        stem[i] = towupper(stem[i]);
                    }
                    else
                    {
                        stem[i] = towlower(stem[i]);
                    }
                }
                hr = StringCchPrintf(result, cchMax, L"%s%s", stem.c_str(), extension.c_str());
            }
            else
            {
                hr = StringCchCopy(result, cchMax, source);
            }
        }
        else
        {
            hr = StringCchCopy(result, cchMax, source);
        }
    }

    return hr;
}