#pragma once

#include <algorithm> // reverse, remove, fill, find, none_of
#include <array> // array
#include <cassert> // assert
#include <ciso646> // and, or
#include <clocale> // localeconv, lconv
#include <cmath> // labs, isfinite, isnan, signbit
#include <cstddef> // size_t, ptrdiff_t
#include <cstdint> // uint8_t
#include <cstdio> // snprintf
#include <limits> // numeric_limits
#include <string> // string
#include <type_traits> // is_same

#include <nlohmann/detail/exceptions.hpp>
#include <nlohmann/detail/conversions/to_chars.hpp>
#include <nlohmann/detail/macro_scope.hpp>
#include <nlohmann/detail/meta.hpp>
#include <nlohmann/detail/output/output_adapters.hpp>
#include <nlohmann/detail/output/primitive_serializer.hpp>
#include <nlohmann/detail/value_t.hpp>

namespace nlohmann
{
namespace detail
{
///////////////////
// serialization //
///////////////////

template<typename BasicJsonType>
class serializer
{
    using primitive_serializer_t = primitive_serializer<BasicJsonType>;
    using string_t = typename BasicJsonType::string_t;
    using number_float_t = typename BasicJsonType::number_float_t;
    using number_integer_t = typename BasicJsonType::number_integer_t;
    using number_unsigned_t = typename BasicJsonType::number_unsigned_t;
    static constexpr uint8_t UTF8_ACCEPT = 0;
    static constexpr uint8_t UTF8_REJECT = 1;

  public:
    /*!
    @param[in] s  output stream to serialize to
    @param[in] ichar  indentation character to use
    */
    serializer(output_adapter_t<char> s, const char ichar)
        : o(std::move(s)), indent_char(ichar), indent_string(512, indent_char)
    {}

    // delete because of pointer members
    serializer(const serializer&) = delete;
    serializer& operator=(const serializer&) = delete;

    /*!
    @brief internal implementation of the serialization function

    This function is called by the public member function dump and organizes
    the serialization internally. The indentation level is propagated as
    additional parameter. In case of arrays and objects, the function is
    called recursively.

    - strings and object keys are escaped using `escape_string()`
    - integer numbers are converted implicitly via `operator<<`
    - floating-point numbers are converted to a string using `"%g"` format

    @param[in] val             value to serialize
    @param[in] pretty_print    whether the output shall be pretty-printed
    @param[in] indent_step     the indent level
    @param[in] current_indent  the current indent level (only used internally)
    */
    void dump(const BasicJsonType& val, const bool pretty_print,
              const bool ensure_ascii,
              const unsigned int indent_step,
              const unsigned int current_indent = 0)
    {
        switch (val.m_type)
        {
            case value_t::object:
            {
                if (val.m_value.object->empty())
                {
                    o->write_characters("{}", 2);
                    return;
                }

                if (pretty_print)
                {
                    o->write_characters("{\n", 2);

                    // variable to hold indentation for recursive calls
                    const auto new_indent = current_indent + indent_step;
                    if (JSON_UNLIKELY(indent_string.size() < new_indent))
                    {
                        indent_string.resize(indent_string.size() * 2, ' ');
                    }

                    // first n-1 elements
                    auto i = val.m_value.object->cbegin();
                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
                    {
                        o->write_characters(indent_string.c_str(), new_indent);
                        o->write_character('\"');
                        prim_serializer.dump_escaped(*o, i->first, ensure_ascii);
                        o->write_characters("\": ", 3);
                        dump(i->second, true, ensure_ascii, indent_step, new_indent);
                        o->write_characters(",\n", 2);
                    }

                    // last element
                    assert(i != val.m_value.object->cend());
                    assert(std::next(i) == val.m_value.object->cend());
                    o->write_characters(indent_string.c_str(), new_indent);
                    o->write_character('\"');
                    prim_serializer.dump_escaped(*o, i->first, ensure_ascii);
                    o->write_characters("\": ", 3);
                    dump(i->second, true, ensure_ascii, indent_step, new_indent);

                    o->write_character('\n');
                    o->write_characters(indent_string.c_str(), current_indent);
                    o->write_character('}');
                }
                else
                {
                    o->write_character('{');

                    // first n-1 elements
                    auto i = val.m_value.object->cbegin();
                    for (std::size_t cnt = 0; cnt < val.m_value.object->size() - 1; ++cnt, ++i)
                    {
                        o->write_character('\"');
                        prim_serializer.dump_escaped(*o, i->first, ensure_ascii);
                        o->write_characters("\":", 2);
                        dump(i->second, false, ensure_ascii, indent_step, current_indent);
                        o->write_character(',');
                    }

                    // last element
                    assert(i != val.m_value.object->cend());
                    assert(std::next(i) == val.m_value.object->cend());
                    o->write_character('\"');
                    prim_serializer.dump_escaped(*o, i->first, ensure_ascii);
                    o->write_characters("\":", 2);
                    dump(i->second, false, ensure_ascii, indent_step, current_indent);

                    o->write_character('}');
                }

                return;
            }

            case value_t::array:
            {
                if (val.m_value.array->empty())
                {
                    o->write_characters("[]", 2);
                    return;
                }

                if (pretty_print)
                {
                    o->write_characters("[\n", 2);

                    // variable to hold indentation for recursive calls
                    const auto new_indent = current_indent + indent_step;
                    if (JSON_UNLIKELY(indent_string.size() < new_indent))
                    {
                        indent_string.resize(indent_string.size() * 2, ' ');
                    }

                    // first n-1 elements
                    for (auto i = val.m_value.array->cbegin();
                            i != val.m_value.array->cend() - 1; ++i)
                    {
                        o->write_characters(indent_string.c_str(), new_indent);
                        dump(*i, true, ensure_ascii, indent_step, new_indent);
                        o->write_characters(",\n", 2);
                    }

                    // last element
                    assert(not val.m_value.array->empty());
                    o->write_characters(indent_string.c_str(), new_indent);
                    dump(val.m_value.array->back(), true, ensure_ascii, indent_step, new_indent);

                    o->write_character('\n');
                    o->write_characters(indent_string.c_str(), current_indent);
                    o->write_character(']');
                }
                else
                {
                    o->write_character('[');

                    // first n-1 elements
                    for (auto i = val.m_value.array->cbegin();
                            i != val.m_value.array->cend() - 1; ++i)
                    {
                        dump(*i, false, ensure_ascii, indent_step, current_indent);
                        o->write_character(',');
                    }

                    // last element
                    assert(not val.m_value.array->empty());
                    dump(val.m_value.array->back(), false, ensure_ascii, indent_step, current_indent);

                    o->write_character(']');
                }

                return;
            }

            case value_t::string:
            {
                o->write_character('\"');
                prim_serializer.dump_escaped(*o, *val.m_value.string, ensure_ascii);
                o->write_character('\"');
                return;
            }

            case value_t::boolean:
            {
                if (val.m_value.boolean)
                {
                    o->write_characters("true", 4);
                }
                else
                {
                    o->write_characters("false", 5);
                }
                return;
            }

            case value_t::number_integer:
            {
                prim_serializer.dump_integer(*o, val.m_value.number_integer);
                return;
            }

            case value_t::number_unsigned:
            {
                prim_serializer.dump_integer(*o, val.m_value.number_unsigned);
                return;
            }

            case value_t::number_float:
            {
                prim_serializer.dump_float(*o, val.m_value.number_float);
                return;
            }

            case value_t::discarded:
            {
                o->write_characters("<discarded>", 11);
                return;
            }

            case value_t::null:
            {
                o->write_characters("null", 4);
                return;
            }
        }
    }

  private:
    /// the output of the serializer
    output_adapter_t<char> o = nullptr;

    /// the indentation character
    const char indent_char;
    /// the indentation string
    string_t indent_string;

    /// used for serializing non-object non-arrays
    primitive_serializer_t prim_serializer;
};
}
}