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//
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//
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// Copyright (c) 2022 Alan de Freitas (alandefreitas at gmail dot com)
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// Copyright (c) 2022 Alan de Freitas (alandefreitas at gmail dot com)
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//
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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//
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// Official repository: https://github.com/boostorg/url
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// Official repository: https://github.com/boostorg/url
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//
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//
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#ifndef BOOST_URL_GRAMMAR_IMPL_UNSIGNED_RULE_HPP
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#ifndef BOOST_URL_GRAMMAR_IMPL_UNSIGNED_RULE_HPP
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#define BOOST_URL_GRAMMAR_IMPL_UNSIGNED_RULE_HPP
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#define BOOST_URL_GRAMMAR_IMPL_UNSIGNED_RULE_HPP
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#include <boost/url/grammar/error.hpp>
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#include <boost/url/grammar/error.hpp>
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#include <boost/url/grammar/digit_chars.hpp>
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#include <boost/url/grammar/digit_chars.hpp>
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#include <algorithm> // VFALCO grr..
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#include <algorithm> // VFALCO grr..
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namespace boost {
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namespace boost {
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namespace urls {
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namespace urls {
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namespace grammar {
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namespace grammar {
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template<class U>
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template<class U>
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auto
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auto
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unsigned_rule<U>::
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unsigned_rule<U>::
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parse(
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parse(
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    char const*& it,
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    char const*& it,
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    char const* end
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    char const* end
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        ) const noexcept ->
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        ) const noexcept ->
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    system::result<value_type>
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    system::result<value_type>
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{
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{
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    if(it == end)
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    if(it == end)
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    {
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    {
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        // end
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        // end
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        BOOST_URL_RETURN_EC(
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        BOOST_URL_RETURN_EC(
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            error::mismatch);
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            error::mismatch);
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    }
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    }
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    if(*it == '0')
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    if(*it == '0')
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    {
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    {
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        ++it;
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        ++it;
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        if( it == end ||
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        if( it == end ||
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            ! digit_chars(*it))
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            ! digit_chars(*it))
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        {
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        {
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            return U(0);
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            return U(0);
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        }
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        }
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        // bad leading zero
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        // bad leading zero
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        BOOST_URL_RETURN_EC(
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        BOOST_URL_RETURN_EC(
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            error::invalid);
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            error::invalid);
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    }
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    }
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    if(! digit_chars(*it))
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    if(! digit_chars(*it))
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    {
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    {
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        // expected digit
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        // expected digit
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        BOOST_URL_RETURN_EC(
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        BOOST_URL_RETURN_EC(
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            error::mismatch);
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            error::mismatch);
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    }
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    }
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    static constexpr U Digits10 =
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    static constexpr U Digits10 =
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        std::numeric_limits<
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        std::numeric_limits<
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            U>::digits10;
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            U>::digits10;
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    static constexpr U ten = 10;
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    static constexpr U ten = 10;
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    char const* safe_end;
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    char const* safe_end;
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    if(static_cast<std::size_t>(
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    if(static_cast<std::size_t>(
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            end - it) >= Digits10)
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            end - it) >= Digits10)
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        safe_end = it + Digits10;
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        safe_end = it + Digits10;
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    else
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    else
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        safe_end = end;
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        safe_end = end;
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    U u = *it - '0';
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    U u = *it - '0';
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    ++it;
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    ++it;
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    while(it != safe_end &&
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    while(it != safe_end &&
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        digit_chars(*it))
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        digit_chars(*it))
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    {
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    {
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        char const dig = *it - '0';
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        char const dig = *it - '0';
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        u = u * ten + dig;
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        u = u * ten + dig;
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        ++it;
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        ++it;
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    }
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    }
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    if( it != end &&
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    if( it != end &&
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        digit_chars(*it))
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        digit_chars(*it))
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    {
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    {
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        static constexpr U Max = (
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        static constexpr U Max = (
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            std::numeric_limits<
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            std::numeric_limits<
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                U>::max)();
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                U>::max)();
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        static constexpr
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        static constexpr
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            auto div = (Max / ten);
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            auto div = (Max / ten);
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        static constexpr
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        static constexpr
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            char rem = (Max % ten);
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            char rem = (Max % ten);
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        char const dig = *it - '0';
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        char const dig = *it - '0';
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        if( u > div || (
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        if( u > div || (
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            u == div && dig > rem))
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            u == div && dig > rem))
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        {
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        {
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            // integer overflow
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            // integer overflow
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            BOOST_URL_RETURN_EC(
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            BOOST_URL_RETURN_EC(
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                error::invalid);
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                error::invalid);
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        }
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        }
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        u = u * ten + dig;
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        u = u * ten + dig;
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        ++it;
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        ++it;
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        if( it < end &&
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        if( it < end &&
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            digit_chars(*it))
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            digit_chars(*it))
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        {
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        {
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            // integer overflow
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            // integer overflow
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            BOOST_URL_RETURN_EC(
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            BOOST_URL_RETURN_EC(
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                error::invalid);
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                error::invalid);
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        }
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        }
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    }
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    }
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    return u;
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    return u;
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}
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}
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} // grammar
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} // grammar
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} // urls
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} // urls
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} // boost
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} // boost
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#endif
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#endif