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//
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//
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// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.com)
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// Copyright (c) 2019 Vinnie Falco (vinnie.falco@gmail.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/json
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// Official repository: https://github.com/boostorg/json
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//
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//
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#ifndef BOOST_JSON_DETAIL_BUFFER_HPP
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#ifndef BOOST_JSON_DETAIL_BUFFER_HPP
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#define BOOST_JSON_DETAIL_BUFFER_HPP
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#define BOOST_JSON_DETAIL_BUFFER_HPP
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#include <boost/json/detail/config.hpp>
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#include <boost/json/detail/config.hpp>
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#include <boost/json/string_view.hpp>
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#include <boost/json/string_view.hpp>
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#include <cstring>
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#include <cstring>
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namespace boost {
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namespace boost {
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namespace json {
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namespace json {
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namespace detail {
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namespace detail {
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// A simple string-like temporary static buffer
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// A simple string-like temporary static buffer
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template<std::size_t N>
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template<std::size_t N>
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class buffer
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class buffer
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{
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{
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public:
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public:
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    using size_type = std::size_t;
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    using size_type = std::size_t;
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    buffer() = default;
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    buffer() = default;
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    bool
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    bool
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    empty() const noexcept
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    empty() const noexcept
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    {
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    {
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        return size_ == 0;
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        return size_ == 0;
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    }
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    }
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    string_view
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    string_view
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    get() const noexcept
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    get() const noexcept
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    {
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    {
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        return {buf_, size_};
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        return {buf_, size_};
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    }
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    }
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    operator string_view() const noexcept
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    operator string_view() const noexcept
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    {
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    {
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        return get();
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        return get();
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    }
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    }
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    char const*
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    char const*
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    data() const noexcept
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    data() const noexcept
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    {
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    {
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        return buf_;
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        return buf_;
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    }
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    }
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    size_type
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    size_type
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    size() const noexcept
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    size() const noexcept
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    {
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    {
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        return size_;
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        return size_;
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    }
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    }
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    size_type
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    size_type
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    capacity() const noexcept
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    capacity() const noexcept
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    {
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    {
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        return N - size_;
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        return N - size_;
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    }
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    }
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    size_type
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    size_type
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    max_size() const noexcept
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    max_size() const noexcept
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    {
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    {
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        return N;
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        return N;
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    }
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    }
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    void
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    void
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    clear() noexcept
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    clear() noexcept
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    {
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    {
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        size_ = 0;
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        size_ = 0;
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    }
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    }
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    void
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    void
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    push_back(char ch) noexcept
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    push_back(char ch) noexcept
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    {
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    {
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        BOOST_ASSERT(capacity() > 0);
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        BOOST_ASSERT(capacity() > 0);
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        buf_[size_++] = ch;
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        buf_[size_++] = ch;
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    }
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    }
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    // append an unescaped string
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    // append an unescaped string
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    void
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    void
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    append(
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    append(
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        char const* s,
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        char const* s,
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        size_type n)
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        size_type n)
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    {
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    {
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        BOOST_ASSERT(n <= N - size_);
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        BOOST_ASSERT(n <= N - size_);
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        std::memcpy(buf_ + size_, s, n);
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        std::memcpy(buf_ + size_, s, n);
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        size_ += n;
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        size_ += n;
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    }
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    }
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    // append valid 32-bit code point as utf8
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    // append valid 32-bit code point as utf8
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    void
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    void
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    append_utf8(
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    append_utf8(
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        unsigned long cp) noexcept
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        unsigned long cp) noexcept
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    {
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    {
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        auto dest = buf_ + size_;
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        auto dest = buf_ + size_;
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        if(cp < 0x80)
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        if(cp < 0x80)
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        {
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        {
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            BOOST_ASSERT(size_ <= N - 1);
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            BOOST_ASSERT(size_ <= N - 1);
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            dest[0] = static_cast<char>(cp);
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            dest[0] = static_cast<char>(cp);
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            size_ += 1;
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            size_ += 1;
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            return;
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            return;
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        }
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        }
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        if(cp < 0x800)
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        if(cp < 0x800)
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        {
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        {
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            BOOST_ASSERT(size_ <= N - 2);
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            BOOST_ASSERT(size_ <= N - 2);
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            dest[0] = static_cast<char>( (cp >> 6)          | 0xc0);
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            dest[0] = static_cast<char>( (cp >> 6)          | 0xc0);
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            dest[1] = static_cast<char>( (cp & 0x3f)        | 0x80);
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            dest[1] = static_cast<char>( (cp & 0x3f)        | 0x80);
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            size_ += 2;
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            size_ += 2;
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            return;
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            return;
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        }
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        }
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        if(cp < 0x10000)
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        if(cp < 0x10000)
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        {
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        {
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            BOOST_ASSERT(size_ <= N - 3);
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            BOOST_ASSERT(size_ <= N - 3);
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            dest[0] = static_cast<char>( (cp >> 12)         | 0xe0);
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            dest[0] = static_cast<char>( (cp >> 12)         | 0xe0);
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            dest[1] = static_cast<char>(((cp >> 6) & 0x3f)  | 0x80);
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            dest[1] = static_cast<char>(((cp >> 6) & 0x3f)  | 0x80);
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            dest[2] = static_cast<char>( (cp       & 0x3f)  | 0x80);
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            dest[2] = static_cast<char>( (cp       & 0x3f)  | 0x80);
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            size_ += 3;
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            size_ += 3;
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            return;
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            return;
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        }
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        }
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        {
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        {
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            BOOST_ASSERT(size_ <= N - 4);
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            BOOST_ASSERT(size_ <= N - 4);
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            dest[0] = static_cast<char>( (cp >> 18)         | 0xf0);
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            dest[0] = static_cast<char>( (cp >> 18)         | 0xf0);
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            dest[1] = static_cast<char>(((cp >> 12) & 0x3f) | 0x80);
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            dest[1] = static_cast<char>(((cp >> 12) & 0x3f) | 0x80);
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            dest[2] = static_cast<char>(((cp >> 6)  & 0x3f) | 0x80);
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            dest[2] = static_cast<char>(((cp >> 6)  & 0x3f) | 0x80);
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            dest[3] = static_cast<char>( (cp        & 0x3f) | 0x80);
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            dest[3] = static_cast<char>( (cp        & 0x3f) | 0x80);
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            size_ += 4;
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            size_ += 4;
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        }
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        }
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    }
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    }
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private:
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private:
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    char buf_[N];
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    char buf_[N];
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    size_type size_ = 0;
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    size_type size_ = 0;
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};
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};
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} // detail
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} // detail
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} // namespace json
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} // namespace json
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} // namespace boost
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} // namespace boost
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#endif
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#endif