#ifndef LIBAV_FMT_CONTEXT_HPP
#define LIBAV_FMT_CONTEXT_HPP

extern "C"{
#  include <libavformat/avformat.h>
}

#include "libav/libav.hpp"

#include <utility> //exchange

namespace libav::fmt{
	class input_context{
	private:
		AVFormatContext* m_context = nullptr;
	public:
		input_context(void) = default;
		input_context(const char* filename){
			if(avformat_open_input(&m_context, filename, 0, 0) < 0){
				return;
			}
			if(avformat_find_stream_info(m_context, 0) < 0){
				reset();
			}
		}
		input_context(const input_context&) = delete;
		input_context(input_context&& i)noexcept:
			m_context(std::exchange(i.m_context, nullptr)){}
		~input_context(void){
			reset();
		}

		input_context& operator=(const input_context&) = delete;
		input_context& operator=(input_context&& i){
			std::swap(m_context, i.m_context);
			return *this;
		}
		void reset(AVFormatContext* context = nullptr){
			if(m_context)
				avformat_close_input(&m_context);
			m_context = context;
		}
		AVFormatContext* release(void){
			return std::exchange(m_context, nullptr);
		}

		AVFormatContext* operator->(void){
			return m_context;
		}
		const AVFormatContext* operator->(void)const{
			return m_context;
		}
		AVFormatContext* get(void){
			return m_context;
		}
		const AVFormatContext* get(void)const{
			return m_context;
		}
		operator AVFormatContext*(void){
			return m_context;
		}
		operator const AVFormatContext*(void)const{
			return m_context;
		}
		operator bool(void)const{
			return m_context;
		}
	};
	class output_context{
	private:
		AVFormatContext* m_context = nullptr;
	public:
		output_context(const char* filename, const char* format = nullptr){
			if(avformat_alloc_output_context2(&m_context, av_guess_format(format, NULL, NULL), NULL, filename) < 0)
				return;
			if(!(m_context->oformat->flags & AVFMT_NOFILE)){
				if(avio_open(&m_context->pb, filename, AVIO_FLAG_WRITE) < 0){
					avformat_free_context(m_context);
				}
			}
		}
		output_context(const output_context&) = delete;
		output_context(output_context&& o)noexcept:
			m_context(std::exchange(o.m_context, nullptr)){}
		~output_context(void){
			reset();
		}

		output_context& operator=(const output_context&) = delete;
		output_context& operator=(output_context&& o)noexcept{
			std::swap(m_context, o.m_context);
			return *this;
		}
		void reset(AVFormatContext* context = nullptr){
			if(m_context){
				if(!(m_context->oformat->flags & AVFMT_NOFILE)){
					avio_close(m_context->pb);
				}
				avformat_free_context(m_context);
			}
			m_context = context;
		}
		AVFormatContext* release(void){
			return std::exchange(m_context, nullptr);
		}

		AVFormatContext* operator->(void){
			return m_context;
		}
		const AVFormatContext* operator->(void)const{
			return m_context;
		}
		AVFormatContext* get(void){
			return m_context;
		}
		const AVFormatContext* get(void)const{
			return m_context;
		}
		operator AVFormatContext*(void){
			return m_context;
		}
		operator const AVFormatContext*(void)const{
			return m_context;
		}
		operator bool(void)const{
			return m_context;
		}
	};
}


#endif