#ifndef HV_HTTP2_PARSER_H_
#define HV_HTTP2_PARSER_H_

#ifdef WITH_NGHTTP2
#include "HttpParser.h"
#include "http2def.h"
#include "grpcdef.h"

#include "nghttp2/nghttp2.h"

enum http2_session_state {
 H2_SEND_MAGIC,
 H2_SEND_SETTINGS,
 H2_SEND_PING,
 H2_SEND_HEADERS,
 H2_SEND_DATA_FRAME_HD,
 H2_SEND_DATA,
 H2_SEND_DONE,

 H2_WANT_SEND,
 H2_WANT_RECV,

 H2_RECV_SETTINGS,
 H2_RECV_PING,
 H2_RECV_HEADERS,
 H2_RECV_DATA,
};

class Http2Parser : public HttpParser {
public:
 static nghttp2_session_callbacks* cbs;
 nghttp2_session* session;
 http2_session_state state;
 HttpMessage* submited;
 HttpMessage* parsed;
 int error;
 int stream_id;
 int stream_closed;
 int frame_type_when_stream_closed;
 // http2_frame_hd + grpc_message_hd
 // at least HTTP2_FRAME_HDLEN + GRPC_MESSAGE_HDLEN = 9 + 5 = 14
 unsigned char frame_hdbuf[32];

 Http2Parser(http_session_type type = HTTP_CLIENT);
 virtual ~Http2Parser();

 virtual int GetSendData(char** data, size_t* len);
 virtual int FeedRecvData(const char* data, size_t len);

 virtual int GetState() {
 return (int)state;
 }

 virtual bool WantRecv() {
 return state == H2_WANT_RECV;
 }

 virtual bool WantSend() {
 return state <= H2_WANT_SEND;
 }

 virtual bool IsComplete() {
 return stream_closed && (frame_type_when_stream_closed == HTTP2_DATA || frame_type_when_stream_closed == HTTP2_HEADERS);
 }

 virtual int GetError() {
 return error;
 }

 virtual const char* StrError(int error) {
 //return nghttp2_http2_strerror(error);
 return nghttp2_strerror(error);
 }

 // client
 // SubmitRequest -> while(GetSendData) {send} -> InitResponse -> do {recv -> FeedRecvData} while(WantRecv)
 virtual int SubmitRequest(HttpRequest* req);
 virtual int InitResponse(HttpResponse* res);

 // server
 // InitRequest -> do {recv -> FeedRecvData} while(WantRecv) -> SubmitResponse -> while(GetSendData) {send}
 virtual int InitRequest(HttpRequest* req);
 virtual int SubmitResponse(HttpResponse* res);

};

#endif

#endif // HV_HTTP2_PARSER_H_