#pragma once
#ifndef _NB_SMARTSTREAM
#define _NB_SMARTSTREAM

#include <ostream>
#include <type_traits>
#include <unordered_map>
#include <utility>
#include <vector>

namespace nb {

typedef std::pair<unsigned int, std::string> SmartTextKV;

//template<typename T=std::string>
struct SmartText {
    std::string msg;
    SmartTextKV kv = {0, ""};
};

typedef std::string (*SmartTextFormatter)(std::string, std::string);

typedef std::unordered_map<unsigned int, SmartTextFormatter> SmartFormatMap;

template <typename ST>
class SmartOStreamBase {
public:
    virtual void process(const SmartText&) = 0;

    static const SmartFormatMap Formatters;
    enum FormatterCodes : unsigned int;
protected:
    SmartOStreamBase(ST& stream) : _ostream{&stream} {}
    ST* _ostream;

};

template<typename ST, typename Derived>
class SmartOStreamBaseImpl;

template<typename ST, typename Derived=void>
class SmartOStream;

template<typename ST, typename STD, typename Derived>
class SmartOStreamBaseImpl<SmartOStream<ST, STD>, Derived> : public SmartOStreamBase<SmartOStream<ST, STD>>{
    using Base = SmartOStreamBase<SmartOStream<ST, STD>>;
public:
    using StreamType = SmartOStream<ST, STD>;
    using Base::process;
    using Base::Formatters;

protected:
    using Base::Base;
};

template<typename C, typename T, typename Derived>
class SmartOStreamBaseImpl<std::basic_ostream<C, T>, Derived> : public SmartOStreamBase<std::basic_ostream<C, T>> {
    using Base = SmartOStreamBase<std::basic_ostream<C, T>>;
public:
    using StreamType = std::basic_ostream<C, T>;
    using Base::process;
    using Base::Formatters;

protected:
    using Base::Base;
};


template<typename StreamType, typename Derived>
class SmartOStream : public SmartOStreamBaseImpl<StreamType, Derived> {
    template <typename ST, typename D, typename U>
    friend SmartOStream<ST, D>& operator<<(SmartOStream<ST, D>&, const U&);
public:
    using Base = SmartOStreamBaseImpl<StreamType, Derived>;
    
    StreamType* getStream() const { return _ostream; }

    template <typename X>
    void process(const X& val) {
        *_ostream << val;
    }

    void process(const SmartText&);

    static const SmartFormatMap Formatters;

protected:
    using Base::Base;
    using Base::_ostream;

    static std::string defaultFormatter(std::string msg, std::string fmt) {
        return msg;
    }
};

template<typename ST, typename D>
enum SmartOStream<ST, D>::FormatterCodes : unsigned int {
    DEFAULT
};

template<typename ST, typename D>
const SmartFormatMap SmartOStream<ST, D>::Formatters = {
    {SmartOStream<ST, D>::FormatterCodes::DEFAULT, defaultFormatter}
};

template <typename ST, typename D, typename U>
SmartOStream<ST, D>& operator<<(SmartOStream<ST, D>& stream, const U& msg) {
    static_cast<D*>(&stream)->process(msg);
    return stream;
}

template <typename ST, typename U>
SmartOStream<ST, void>& operator<<(SmartOStream<ST, void>& stream, const U& msg) {
    static_cast<SmartOStream<ST, void>*>(&stream)->process(msg);
    return stream;
}

template<typename ST, typename D>
void SmartOStream<ST, D>::process(const SmartText& msg) {
    using Derived = typename std::conditional<std::is_void<D>::value, SmartOStream<ST, void>, D>::type;
    try {
        *_ostream << Derived::Formatters.at(msg.kv.first)(msg.msg, msg.kv.second);
    } catch (const std::out_of_range& e) {
        *_ostream << Derived::Formatters.at(0)(msg.msg, msg.kv.second);
    }
}

template<typename ST, typename D>
class SmartTerminal : public SmartOStream<ST, SmartTerminal<ST, D>> {
    using Base = SmartOStream<ST, SmartTerminal<ST, D>>;
public:
    using Base::Base;

    static const SmartFormatMap Formatters;
    enum FormatterCodes : unsigned int;

protected:

};

template <typename ST, typename D>
enum SmartTerminal<ST, D>::FormatterCodes : unsigned int {
    DEFAULT,
    COLOR,
    BACKGROUND,
    BOLD,
    CLEAR
};

{

template<typename ST, typename D>
const SmartTerminal<ST, D>::Formatters = {
    {SmartTerminal<ST>}
};

}

}

#endif // _NB_SMARTSTREAM