#define TFE_STRING_MAX		2048
#define TFE_SYMBOL_MAX		64
enum tfe_session_proto
{
	SESSION_PROTO_PLAIN=0,
	SESSION_PROTO_SSL,
	SESSION_PROTO_QUIC,
	SESSION_PROTO_SPDY
};
enum tfe_app_proto
{
	APP_PROTO_HTTP1,
	APP_PROTO_HTTP2,
	APP_PROTO_WS,		//websocket
	APP_PROTO_QUIC		//QUIC is a protocol that cross session layer and application layer.
};
enum tfe_conn_dir
{
	CONN_DIR_DOWNSTREAM=0,	//From client to proxy, aka client-side.
	CONN_DIR_UPSTREAM		//From proxy to server, aka server-side.
};
enum tfe_conn_status
{
	CONN_STATUS_NONE,
	CONN_STATUS_ESTABLISHED,
	CONN_STATUS_CLOSED,
};

/* single dst or src socket bufferevent descriptor */
struct tfe_conn
{
	struct layer_addr addr;
	enum tfe_conn_status status;
    struct bufferevent *bev;
} ;

struct tfe_stream
{

	struct tfe_conn upstream;		
	struct tfe_conn downstream;
};


enum tfe_stream_action
{
	ACTION_FORWARD_DATA,
	ACTION_DEFER_DATA,
	ACTION_DROP_DATA
};
enum tfe_stream_action_opt
{
	ACTION_OPT_FOWARD_BYTES,	//value is size_t, default: forward entire data
	ACTION_OPT_DEFER_TIME_TV,	//value is "struct timeval " which defines in <time.h>, default: time defer is not enabled
	ACTION_OPT_DEFER_BYTES,		//value is size_t, default: defer entire data
	ACTION_OPT_DROP_BYTES		//value is size_t, default: drop entire data
};
enum tfe_stream_close_reason
{
	REASON_PASSIVE_CLOSED,
	REASON_ACTIVE_CLOSED,
	REASON_ERROR
};
int tfe_stream_action_set_opt(const struct tfe_stream* stream,enum tfe_stream_action_opt type, void* value, size_t size);
/*
@return 0 if successful, or -1 if an error occurred
*/

int tfe_stream_write(const struct tfe_stream* stream, enum tfe_conn_dir dir, const unsigned char *data, size_t len);

struct tfe_stream_write_ctx{};
//following tfe_stream_write_xx functions are NOT thread safe, MUST be called in the stream process thread.
struct tfe_stream_write_ctx* tfe_stream_write_frag_start(const struct tfe_stream* stream, enum tfe_conn_dir dir);
/*
@return 0 if successful, or -1 if an error occurred
*/
int tfe_stream_write_frag(struct tfe_stream_write_ctx* w_ctx,const unsigned char *data, size_t size);
void tfe_stream_write_frag_end(struct tfe_stream_write_ctx* w_ctx);
//Return 1 for identify as its traffic;
//Return 0 for unknown traffic;
typedef tfe_stream_action stream_open_cb_t(const struct tfe_stream* stream, unsigned int thread_id, enum tfe_conn_dir dir, const unsigned char *data, size_t len, void **pme);
typedef tfe_stream_action stream_data_cb_t(const struct tfe_stream* stream, unsigned int thread_id, enum tfe_conn_dir dir, const unsigned char *data, size_t len, void **pme);
typedef void stream_close_cb_t(const struct tfe_stream* stream,  unsigned int thread_id, enum tfe_stream_close_reason reason, void **pme);

void tfe_stream_detach(const struct tfe_stream* stream);
int tfe_stream_preempt(const struct tfe_stream* stream);

int stream_shutdown(const struct tfe_stream* stream);//close both sides of the stream.
int stream_shutdown_dir(const struct tfe_stream* stream, enum tfe_conn_dir dir);
//typedef int proto_onwrite_cb_t(struct tfe_stream*, struct evbuffer *data, void **pme);

struct tfe_plugin
{
	char symbol[TFE_SYMBOL_MAX];
	enum tfe_app_proto proto;
	stream_open_cb_t* on_open;
	stream_data_cb_t* on_data;
	stream_close_cb_t* on_close;
//	proto_onwrite_cb_t *onwrite;
	
};
int tfe_io_write(struct pxy_conn_desc* dest,int dir,struct evbuffer *data);

int tfe_xxx_proto_init(struct tfe_plugin*m);