ranges

[[nodiscard]] inline auto SDL::GetDisplays()
{
    const auto validDisplayIndices = ranges::views::ints(0, SDL_GetNumVideoDisplays());
    constexpr auto fetchDisplayData = ranges::views::transform([](const int displayIndex) -> std::optional<Display> {
        Display::DPI dpi;
        if (SDL_GetDisplayDPI(displayIndex, &dpi.Diagonal, &dpi.Horizontal, &dpi.Vertical) != 0)
            return std::nullopt;

        SDL_Rect bounds;
        if (SDL_GetDisplayBounds(displayIndex, &bounds) != 0)
            return std::nullopt;

        SDL_DisplayMode mode;
        if (SDL_GetCurrentDisplayMode(displayIndex, &mode) != 0)
            return std::nullopt;

        return Display{ displayIndex, SDL_GetDisplayName(displayIndex), Units::Pixels{ bounds.x }, Units::Pixels{ bounds.y }, Units::Pixels{ bounds.w },
            Units::Pixels{ bounds.h }, dpi, mode.refresh_rate };
    });
    constexpr auto removeEmptyOptionals = ranges::views::filter([](const auto& display) { return display.has_value(); });
    constexpr auto takeOptionalValues = ranges::views::transform([](const auto& opt) { return *opt; });
    return validDisplayIndices | fetchDisplayData | removeEmptyOptionals | takeOptionalValues;
}