/*
  * RTP demuxer definitions
  * Copyright (c) 2002 Fabrice Bellard
  * Copyright (c) 2006 Ryan Martell <rdm4@martellventures.com>
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 #ifndef AVFORMAT_RTPDEC_H
 #define AVFORMAT_RTPDEC_H
 
 #include "libavcodec/avcodec.h"
 #include "avformat.h"
 #include "rtp.h"

 #include "url.h"

 
 typedef struct PayloadContext PayloadContext;
 typedef struct RTPDynamicProtocolHandler_s RTPDynamicProtocolHandler;
 
 #define RTP_MIN_PACKET_LENGTH 12

 #define RTP_MAX_PACKET_LENGTH 1500 /* XXX: suppress this define */

 #define RTP_REORDER_QUEUE_DEFAULT_SIZE 10
 

 #define RTP_NOTS_VALUE ((uint32_t)-1)
 

 typedef struct RTPDemuxContext RTPDemuxContext;

 RTPDemuxContext *rtp_parse_open(AVFormatContext *s1, AVStream *st, URLContext *rtpc, int payload_type, int queue_size);

 void rtp_parse_set_dynamic_protocol(RTPDemuxContext *s, PayloadContext *ctx,
                                     RTPDynamicProtocolHandler *handler);
 int rtp_parse_packet(RTPDemuxContext *s, AVPacket *pkt,

                      uint8_t **buf, int len);

 void rtp_parse_close(RTPDemuxContext *s);

 int64_t ff_rtp_queued_packet_time(RTPDemuxContext *s);
 void ff_rtp_reset_packet_queue(RTPDemuxContext *s);

 int rtp_get_local_rtp_port(URLContext *h);
 int rtp_get_local_rtcp_port(URLContext *h);
 

 int rtp_set_remote_url(URLContext *h, const char *uri);
 
 /**

  * Send a dummy packet on both port pairs to set up the connection
  * state in potential NAT routers, so that we're able to receive
  * packets.
  *
  * Note, this only works if the NAT router doesn't remap ports. This
  * isn't a standardized procedure, but it works in many cases in practice.
  *
  * The same routine is used with RDT too, even if RDT doesn't use normal
  * RTP packets otherwise.
  */
 void rtp_send_punch_packets(URLContext* rtp_handle);
 
 /**

  * some rtp servers assume client is dead if they don't hear from them...
  * so we send a Receiver Report to the provided ByteIO context
  * (we don't have access to the rtcp handle from here)
  */
 int rtp_check_and_send_back_rr(RTPDemuxContext *s, int count);
 

 /**
  * Get the file handle for the RTCP socket.
  */
 int rtp_get_rtcp_file_handle(URLContext *h);
 

 // these statistics are used for rtcp receiver reports...
 typedef struct {
     uint16_t max_seq;           ///< highest sequence number seen
     uint32_t cycles;            ///< shifted count of sequence number cycles
     uint32_t base_seq;          ///< base sequence number
     uint32_t bad_seq;           ///< last bad sequence number + 1
     int probation;              ///< sequence packets till source is valid
     int received;               ///< packets received
     int expected_prior;         ///< packets expected in last interval
     int received_prior;         ///< packets received in last interval
     uint32_t transit;           ///< relative transit time for previous packet
     uint32_t jitter;            ///< estimated jitter.
 } RTPStatistics;
 

 #define RTP_FLAG_KEY    0x1 ///< RTP packet contains a keyframe

 #define RTP_FLAG_MARKER 0x2 ///< RTP marker bit was set for this packet

 /**
  * Packet parsing for "private" payloads in the RTP specs.
  *
  * @param ctx RTSP demuxer context
  * @param s stream context
  * @param st stream that this packet belongs to
  * @param pkt packet in which to write the parsed data
  * @param timestamp pointer in which to write the timestamp of this RTP packet
  * @param buf pointer to raw RTP packet data
  * @param len length of buf

  * @param flags flags from the RTP packet header (RTP_FLAG_*)

  */
 typedef int (*DynamicPayloadPacketHandlerProc) (AVFormatContext *ctx,
                                                 PayloadContext *s,
                                                 AVStream *st,
                                                 AVPacket * pkt,
                                                 uint32_t *timestamp,
                                                 const uint8_t * buf,
                                                 int len, int flags);
 
 struct RTPDynamicProtocolHandler_s {
     // fields from AVRtpDynamicPayloadType_s
     const char enc_name[50];    /* XXX: still why 50 ? ;-) */

     enum AVMediaType codec_type;

     enum CodecID codec_id;

     int static_payload_id; /* 0 means no payload id is set. 0 is a valid
                             * payload ID (PCMU), too, but that format doesn't
                             * require any custom depacketization code. */

 
     // may be null
     int (*parse_sdp_a_line) (AVFormatContext *s,
                              int st_index,
                              PayloadContext *priv_data,
                              const char *line); ///< Parse the a= line from the sdp field

     PayloadContext *(*alloc) (void); ///< allocate any data needed by the rtp parsing for this dynamic data.
     void (*free)(PayloadContext *protocol_data); ///< free any data needed by the rtp parsing for this dynamic data.

     DynamicPayloadPacketHandlerProc parse_packet; ///< parse handler for this dynamic packet.
 
     struct RTPDynamicProtocolHandler_s *next;
 };
 

 typedef struct RTPPacket {
     uint16_t seq;
     uint8_t *buf;
     int len;
     int64_t recvtime;
     struct RTPPacket *next;
 } RTPPacket;
 

 // moved out of rtp.c, because the h264 decoder needs to know about this structure..
 struct RTPDemuxContext {
     AVFormatContext *ic;
     AVStream *st;
     int payload_type;
     uint32_t ssrc;
     uint16_t seq;
     uint32_t timestamp;
     uint32_t base_timestamp;
     uint32_t cur_timestamp;

     int64_t  range_start_offset;

     int max_payload_size;
     struct MpegTSContext *ts;   /* only used for MP2T payloads */
     int read_buf_index;
     int read_buf_size;
     /* used to send back RTCP RR */
     URLContext *rtp_ctx;
     char hostname[256];
 
     RTPStatistics statistics; ///< Statistics for this stream (used by RTCP receiver reports)
 

     /** Fields for packet reordering @{ */
     int prev_ret;     ///< The return value of the actual parsing of the previous packet
     RTPPacket* queue; ///< A sorted queue of buffered packets not yet returned
     int queue_len;    ///< The number of packets in queue
     int queue_size;   ///< The size of queue, or 0 if reordering is disabled
     /*@}*/
 

     /* rtcp sender statistics receive */
     int64_t last_rtcp_ntp_time;    // TODO: move into statistics

     int64_t first_rtcp_ntp_time;   // TODO: move into statistics

     uint32_t last_rtcp_timestamp;  // TODO: move into statistics

     int64_t rtcp_ts_offset;

 
     /* rtcp sender statistics */
     unsigned int packet_count;     // TODO: move into statistics (outgoing)
     unsigned int octet_count;      // TODO: move into statistics (outgoing)
     unsigned int last_octet_count; // TODO: move into statistics (outgoing)
     int first_packet;
     /* buffer for output */
     uint8_t buf[RTP_MAX_PACKET_LENGTH];
     uint8_t *buf_ptr;
 
     /* dynamic payload stuff */
     DynamicPayloadPacketHandlerProc parse_packet;     ///< This is also copied from the dynamic protocol handler structure
     PayloadContext *dynamic_protocol_context;        ///< This is a copy from the values setup from the sdp parsing, in rtsp.c don't free me.
     int max_frames_per_packet;
 };
 
 void ff_register_dynamic_payload_handler(RTPDynamicProtocolHandler *handler);

 RTPDynamicProtocolHandler *ff_rtp_handler_find_by_name(const char *name,
                                                   enum AVMediaType codec_type);
 RTPDynamicProtocolHandler *ff_rtp_handler_find_by_id(int id,
                                                 enum AVMediaType codec_type);

 int ff_rtsp_next_attr_and_value(const char **p, char *attr, int attr_size, char *value, int value_size); ///< from rtsp.c, but used by rtp dynamic protocol handlers.

 int ff_parse_fmtp(AVStream *stream, PayloadContext *data, const char *p,
                   int (*parse_fmtp)(AVStream *stream,
                                     PayloadContext *data,
                                     char *attr, char *value));
 

 void av_register_rtp_dynamic_payload_handlers(void);
 
 #endif /* AVFORMAT_RTPDEC_H */