static_assert( __cplusplus > 2020'99 );

#include "delimited_list.h"

#include <Alepha/error.h>

#include <Alepha/IOStreams/StreamState.h>

namespace Alepha::Hydrogen  ::detail::  delimited_list_m
{

	namespace
	{
		namespace C
		{
			const bool debug= false;
		}

		namespace impl_cc
		{
			struct DelimitedListStreambuf;
		}

		IOStreams::StreamState< impl_cc::DelimitedListStreambuf * > tracker{ [] { return nullptr; } };
	}

	struct impl_cc::DelimitedListStreambuf
		: virtual public IOStreams::StackableStreambuf, virtual public std::streambuf
	{
		private:
			DelimiterWriter writer;
			bool first= true;

		public:
			explicit
			DelimitedListStreambuf( std::ios &ios, const DelimiterWriter writer )
				: StackableStreambuf( ios ), writer( writer )
			{
				tracker.get( ios )= this;
				if( C::debug ) error() << "Streambuf adapted." << std::endl;
			}

			void
			doNext( std::ostream &out )
			{
				if( C::debug ) error() << "Do Next called" << std::endl;
				if( not first ) writer( out );
				first= false;
			}

		private:
			void writeChar( char ) override { throw "Unimpl"; }
			void drain() override {} // Do nothing...

			int
			overflow( const int ch ) override
			{
				if( C::debug ) error() << "Overflow called" << std::endl;
				return forwardOverflow( ch );
			}
	};


	std::ostream &
	impl::operator << ( std::ostream &os, MarkItem_t )
	{
		if( C::debug ) error() << "Marker called" << std::endl;
		auto thisTracker= tracker.get( os );
		if( thisTracker != nullptr ) thisTracker->doNext( os );

		return os;
	}

	void
	impl::build_streambuf( std::ostream &os, StartDelimitedList &&params )
	{
		new impl_cc::DelimitedListStreambuf( os, params.writer );
	}
}