#include "utf8_iterator.hpp"

namespace fud {

std::optional<ExtUtf8> Utf8Iterator::peek() const
{
    if (m_index >= m_view.length()) {
        return std::nullopt;
    }

    auto utf8 = ExtUtf8::fromStringView(m_view, m_index);

    if (!utf8.valid()) {
        return std::nullopt;
    }

    return utf8;
}

std::optional<ExtUtf8> Utf8Iterator::next()
{
    if (m_index >= m_view.length()) {
        m_index = m_view.length();
        return std::nullopt;
    }

    auto utf8 = ExtUtf8::fromStringView(m_view, m_index);

    if (!utf8.valid()) {
        m_index = m_view.length();
        return std::nullopt;
    }

    m_index += utf8.size();
    return utf8;
}

} // namespace fud