/* 
 * Copyright (C) 2008-2011 Teluu Inc. (http://www.teluu.com)
 * Copyright (C) 2003-2008 Benny Prijono <benny@prijono.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
 */
#ifndef __PJMEDIA_RTCP_H__
#define __PJMEDIA_RTCP_H__

/**
 * @file rtcp.h
 * @brief RTCP implementation.
 */

#include <pjmedia/types.h>
#include <pjmedia/rtcp_xr.h>
#include <pjmedia/rtp.h>

PJ_BEGIN_DECL


/**
 * @defgroup PJMED_RTCP RTCP Session and Encapsulation (RFC 3550)
 * @ingroup PJMEDIA_SESSION
 * @brief RTCP format and session management
 * @{
 *
 * PJMEDIA implements subsets of RTCP specification (RFC 3550) to monitor
 * the quality of the real-time media (audio/video) transmission. In
 * addition to the standard quality monitoring and reporting with RTCP
 * SR and RR types, PJMEDIA's RTCP implementation is able to report
 * extended statistics for incoming streams, such as packet duplications,
 * reorder, discarded, and loss period (to distinguish between random
 * and burst loss).
 *
 * The bidirectional media quality statistic is represented with
 * #pjmedia_rtcp_stat structure.
 *
 * When application uses the stream interface (see @ref PJMED_STRM),
 * application may retrieve the RTCP statistic by calling 
 * #pjmedia_stream_get_stat() function.
 */

 
#pragma pack(1)

/**
 * RTCP sender report.
 */
typedef struct pjmedia_rtcp_sr
{
    pj_uint32_t     ntp_sec;        /**< NTP time, seconds part.        */
    pj_uint32_t     ntp_frac;       /**< NTP time, fractions part.      */
    pj_uint32_t     rtp_ts;         /**< RTP timestamp.                 */
    pj_uint32_t     sender_pcount;  /**< Sender packet cound.           */
    pj_uint32_t     sender_bcount;  /**< Sender octet/bytes count.      */
} pjmedia_rtcp_sr;


/**
 * RTCP receiver report.
 */
typedef struct pjmedia_rtcp_rr
{
    pj_uint32_t     ssrc;           /**< SSRC identification.           */
#if defined(PJ_IS_BIG_ENDIAN) && PJ_IS_BIG_ENDIAN!=0
    pj_uint32_t     fract_lost:8;   /**< Fraction lost.                 */
    pj_uint32_t     total_lost_2:8; /**< Total lost, bit 16-23.         */
    pj_uint32_t     total_lost_1:8; /**< Total lost, bit 8-15.          */
    pj_uint32_t     total_lost_0:8; /**< Total lost, bit 0-7.           */
#else
    pj_uint32_t     fract_lost:8;   /**< Fraction lost.                 */
    pj_uint32_t     total_lost_2:8; /**< Total lost, bit 0-7.           */
    pj_uint32_t     total_lost_1:8; /**< Total lost, bit 8-15.          */
    pj_uint32_t     total_lost_0:8; /**< Total lost, bit 16-23.         */
#endif  
    pj_uint32_t     last_seq;       /**< Last sequence number.          */
    pj_uint32_t     jitter;         /**< Jitter.                        */
    pj_uint32_t     lsr;            /**< Last SR.                       */
    pj_uint32_t     dlsr;           /**< Delay since last SR.           */
} pjmedia_rtcp_rr;


/**
 * RTCP common header.
 */
typedef struct pjmedia_rtcp_common
{
#if defined(PJ_IS_BIG_ENDIAN) && PJ_IS_BIG_ENDIAN!=0
    unsigned        version:2;  /**< packet type            */
    unsigned        p:1;        /**< padding flag           */
    unsigned        count:5;    /**< varies by payload type */
    unsigned        pt:8;       /**< payload type           */
#else
    unsigned        count:5;    /**< varies by payload type */
    unsigned        p:1;        /**< padding flag           */
    unsigned        version:2;  /**< packet type            */
    unsigned        pt:8;       /**< payload type           */
#endif
    unsigned        length:16;  /**< packet length          */
    pj_uint32_t     ssrc;       /**< SSRC identification    */
} pjmedia_rtcp_common;


/**
 * RTCP feedback common header.
 */
typedef struct pjmedia_rtcp_fb_common
{
    pjmedia_rtcp_common rtcp_common;
    pj_uint32_t     ssrc_src;   /**< SSRC media source      */
} pjmedia_rtcp_fb_common;

/**
 * This structure declares default RTCP packet (SR) that is sent by pjmedia.
 * Incoming RTCP packet may have different format, and must be parsed
 * manually by application.
 */
typedef struct pjmedia_rtcp_sr_pkt
{
    pjmedia_rtcp_common  common;        /**< Common header.         */
    pjmedia_rtcp_sr      sr;            /**< Sender report.         */
    pjmedia_rtcp_rr      rr;            /**< variable-length list   */
} pjmedia_rtcp_sr_pkt;

/**
 * This structure declares RTCP RR (Receiver Report) packet.
 */
typedef struct pjmedia_rtcp_rr_pkt
{
    pjmedia_rtcp_common  common;        /**< Common header.         */
    pjmedia_rtcp_rr      rr;            /**< variable-length list   */
} pjmedia_rtcp_rr_pkt;


#pragma pack()


/**
 * RTCP SDES structure.
 */
typedef struct pjmedia_rtcp_sdes
{
    pj_str_t    cname;          /**< RTCP SDES type CNAME.      */
    pj_str_t    name;           /**< RTCP SDES type NAME.       */
    pj_str_t    email;          /**< RTCP SDES type EMAIL.      */
    pj_str_t    phone;          /**< RTCP SDES type PHONE.      */
    pj_str_t    loc;            /**< RTCP SDES type LOC.        */
    pj_str_t    tool;           /**< RTCP SDES type TOOL.       */
    pj_str_t    note;           /**< RTCP SDES type NOTE.       */
} pjmedia_rtcp_sdes;


/**
 * NTP time representation.
 */
typedef struct pjmedia_rtcp_ntp_rec
{
    pj_uint32_t     hi;         /**< High order 32-bit part.    */
    pj_uint32_t     lo;         /**< Lo order 32-bit part.      */
} pjmedia_rtcp_ntp_rec;


/**
 * Unidirectional RTP stream statistics.
 */
typedef struct pjmedia_rtcp_stream_stat
{
    pj_time_val     update;     /**< Time of last update.                   */
    unsigned        update_cnt; /**< Number of updates (to calculate avg)   */
    pj_uint32_t     pkt;        /**< Total number of packets                */
    pj_uint32_t     bytes;      /**< Total number of payload/bytes          */
    unsigned        discard;    /**< Total number of discarded packets.     */
    unsigned        loss;       /**< Total number of packets lost           */
    unsigned        reorder;    /**< Total number of out of order packets   */
    unsigned        dup;        /**< Total number of duplicates packets     */

    pj_math_stat    loss_period;/**< Loss period statistics (in usec)       */

    struct {
        unsigned    burst:1;    /**< Burst/sequential packet lost detected  */
        unsigned    random:1;   /**< Random packet lost detected.           */
    } loss_type;                /**< Types of loss detected.                */

    pj_math_stat    jitter;     /**< Jitter statistics (in usec)            */

} pjmedia_rtcp_stream_stat;


/**
 * Bidirectional RTP stream statistics.
 */
typedef struct pjmedia_rtcp_stat
{
    pj_time_val              start; /**< Time when session was created      */

    pjmedia_rtcp_stream_stat tx;    /**< Encoder stream statistics.         */
    pjmedia_rtcp_stream_stat rx;    /**< Decoder stream statistics.         */
    
    pj_math_stat             rtt;   /**< Round trip delay statistic(in usec)*/

    pj_uint32_t              rtp_tx_last_ts; /**< Last TX RTP timestamp.    */
    pj_uint16_t              rtp_tx_last_seq;/**< Last TX RTP sequence.     */

#if defined(PJMEDIA_RTCP_STAT_HAS_IPDV) && PJMEDIA_RTCP_STAT_HAS_IPDV!=0
    pj_math_stat             rx_ipdv;/**< Statistics of IP packet delay
                                          variation in receiving direction
                                          (in usec).                        */
#endif

#if defined(PJMEDIA_RTCP_STAT_HAS_RAW_JITTER) && PJMEDIA_RTCP_STAT_HAS_RAW_JITTER!=0
    pj_math_stat             rx_raw_jitter;/**< Statistic of raw jitter in
                                                receiving direction 
                                                (in usec).                  */
#endif

    pjmedia_rtcp_sdes        peer_sdes; /**< Peer SDES.                     */
    char                     peer_sdes_buf_[PJMEDIA_RTCP_RX_SDES_BUF_LEN];
                                        /**< Peer SDES buffer.              */

} pjmedia_rtcp_stat;


/**
 * RTCP session is used to monitor the RTP session of one endpoint. There
 * should only be one RTCP session for a bidirectional RTP streams.
 */
typedef struct pjmedia_rtcp_session
{
    char                   *name;       /**< Name identification.           */
    pjmedia_rtcp_sr_pkt     rtcp_sr_pkt;/**< Cached RTCP SR packet.         */
    pjmedia_rtcp_rr_pkt     rtcp_rr_pkt;/**< Cached RTCP RR packet.         */
    pjmedia_rtcp_fb_common  rtcp_fb_com;/**< Cached RTCP feedback common 
                                             header packet.                 */
    
    pjmedia_rtp_seq_session seq_ctrl;   /**< RTCP sequence number control.  */
    unsigned                rtp_last_ts;/**< Last timestamp in RX RTP pkt.  */

    unsigned                clock_rate; /**< Clock rate of the stream       */
    unsigned                pkt_size;   /**< Avg pkt size, in samples.      */
    unsigned                dec_pkt_size;/**< Decoding pkt size, in samples.*/
    pj_uint32_t             received;   /**< # pkt received                 */
    pj_uint32_t             exp_prior;  /**< # pkt expected at last interval*/
    pj_uint32_t             rx_prior;   /**< # pkt received at last interval*/
    pj_int32_t              transit;    /**< Rel transit time for prev pkt  */
    pj_uint32_t             jitter;     /**< Scaled jitter                  */
    pj_time_val             tv_base;    /**< Base time, in seconds.         */
    pj_timestamp            ts_base;    /**< Base system timestamp.         */
    pj_timestamp            ts_freq;    /**< System timestamp frequency.    */
    pj_uint32_t             rtp_ts_base;/**< Base RTP timestamp.            */

    pj_uint32_t             rx_lsr;     /**< NTP ts in last SR received     */
    pj_timestamp            rx_lsr_time;/**< Time when last SR is received  */
    pj_uint32_t             peer_ssrc;  /**< Peer SSRC                      */
    
    pjmedia_rtcp_stat       stat;       /**< Bidirectional stream stat.     */

#if defined(PJMEDIA_HAS_RTCP_XR) && (PJMEDIA_HAS_RTCP_XR != 0)
    /**
     * Specify whether RTCP XR processing is enabled on this session.
     */
    pj_bool_t               xr_enabled;

    /**
     * RTCP XR session, only valid if RTCP XR processing is enabled
     * on this session.
     */
    pjmedia_rtcp_xr_session xr_session;
#endif
} pjmedia_rtcp_session;


/**
 * RTCP session settings.
 */
typedef struct pjmedia_rtcp_session_setting
{
    char            *name;              /**< RTCP session name.         */
    unsigned         clock_rate;        /**< Sequence.                  */
    unsigned         samples_per_frame; /**< Timestamp.                 */
    unsigned         dec_samples_per_frame; /**< Timestamp.             */
    pj_uint32_t      ssrc;              /**< Sender SSRC.               */
    pj_uint32_t      rtp_ts_base;       /**< Base RTP timestamp.        */
} pjmedia_rtcp_session_setting;


/**
 * Initialize RTCP session setting.
 *
 * @param settings          The RTCP session setting to be initialized.
 */
PJ_DECL(void) pjmedia_rtcp_session_setting_default(
                                    pjmedia_rtcp_session_setting *settings);


/**
 * Initialize bidirectional RTCP statistics.
 *
 * @param stat              The bidirectional RTCP statistics.
 */
PJ_DECL(void) pjmedia_rtcp_init_stat(pjmedia_rtcp_stat *stat);


/**
 * Initialize RTCP session.
 *
 * @param session           The session
 * @param name              Optional name to identify the session (for
 *                          logging purpose).
 * @param clock_rate        Codec clock rate in samples per second.
 * @param samples_per_frame Average number of samples per frame.
 * @param ssrc              The SSRC used in to identify the session.
 */
PJ_DECL(void) pjmedia_rtcp_init( pjmedia_rtcp_session *session, 
                                 char *name,
                                 unsigned clock_rate,
                                 unsigned samples_per_frame,
                                 pj_uint32_t ssrc );


/**
 * Initialize RTCP session.
 *
 * @param session           The session
 * @param settings          The RTCP session settings.
 */
PJ_DECL(void) pjmedia_rtcp_init2(pjmedia_rtcp_session *session,
                                 const pjmedia_rtcp_session_setting *settings);


/**
 * Update RTCP session with the new settings. Note that any setting field
 * that has a value of zero will not be updated.
 *
 * @param session           The session
 * @param settings          The new RTCP session settings.
 *                          Set a field to zero to leave it unchanged.
 */
PJ_DECL(void)
pjmedia_rtcp_update(pjmedia_rtcp_session *session,
                    const pjmedia_rtcp_session_setting *settings);


/**
 * Utility function to retrieve current NTP timestamp.
 *
 * @param sess              RTCP session.
 * @param ntp               NTP record.
 *
 * @return                  PJ_SUCCESS on success.
 */
PJ_DECL(pj_status_t) pjmedia_rtcp_get_ntp_time(const pjmedia_rtcp_session *sess,
                                               pjmedia_rtcp_ntp_rec *ntp);


/**
 * Deinitialize RTCP session.
 *
 * @param session   The session.
 */
PJ_DECL(void) pjmedia_rtcp_fini( pjmedia_rtcp_session *session);


/**
 * Call this function everytime an RTP packet is received to let the RTCP
 * session do its internal calculations.
 *
 * @param session   The session.
 * @param seq       The RTP packet sequence number, in host byte order.
 * @param ts        The RTP packet timestamp, in host byte order.
 * @param payload   Size of the payload.
 */
PJ_DECL(void) pjmedia_rtcp_rx_rtp( pjmedia_rtcp_session *session, 
                                   unsigned seq, 
                                   unsigned ts,
                                   unsigned payload);


/**
 * Call this function everytime an RTP packet is received to let the RTCP
 * session do its internal calculations.
 *
 * @param session   The session.
 * @param seq       The RTP packet sequence number, in host byte order.
 * @param ts        The RTP packet timestamp, in host byte order.
 * @param payload   Size of the payload.
 * @param discarded Flag to specify whether the packet is discarded.
 */
PJ_DECL(void) pjmedia_rtcp_rx_rtp2(pjmedia_rtcp_session *session, 
                                   unsigned seq, 
                                   unsigned ts,
                                   unsigned payload,
                                   pj_bool_t discarded);


/**
 * Call this function everytime an RTP packet is sent to let the RTCP session
 * do its internal calculations.
 *
 * @param session   The session.
 * @param ptsize    The payload size of the RTP packet (ie packet minus
 *                  RTP header) in bytes.
 */
PJ_DECL(void) pjmedia_rtcp_tx_rtp( pjmedia_rtcp_session *session, 
                                   unsigned ptsize );


/**
 * Call this function when an RTCP packet is received from remote peer.
 * This RTCP packet received from remote is used to calculate the end-to-
 * end delay of the network.
 *
 * @param session   RTCP session.
 * @param rtcp_pkt  The received RTCP packet.
 * @param size      Size of the incoming packet.
 */
PJ_DECL(void) pjmedia_rtcp_rx_rtcp( pjmedia_rtcp_session *session,
                                    const void *rtcp_pkt,
                                    pj_size_t size);


/**
 * Build a RTCP packet to be transmitted to remote RTP peer. This will
 * create RTCP Sender Report (SR) or Receiver Report (RR) depending on
 * whether the endpoint has been transmitting RTP since the last interval.
 * Note that this function will reset the interval counters (such as
 * the ones to calculate fraction lost) in the session.
 *
 * @param session   The RTCP session.
 * @param rtcp_pkt  Upon return, it will contain pointer to the 
 *                  RTCP packet, which can be RTCP SR or RR.
 * @param len       Upon return, it will indicate the size of 
 *                  the RTCP packet.
 */
PJ_DECL(void) pjmedia_rtcp_build_rtcp( pjmedia_rtcp_session *session, 
                                       void **rtcp_pkt, int *len);


/**
 * Build an RTCP SDES (source description) packet. This packet can be
 * appended to other RTCP packets, e.g: RTCP RR/SR, to compose a compound
 * RTCP packet.
 *
 * @param session   The RTCP session.
 * @param buf       The buffer to receive RTCP SDES packet.
 * @param length    On input, it will contain the buffer length.
 *                  On output, it will contain the generated RTCP SDES
 *                  packet length.
 * @param sdes      The source description, see #pjmedia_rtcp_sdes.
 *
 * @return          PJ_SUCCESS on success.
 */
PJ_DECL(pj_status_t) pjmedia_rtcp_build_rtcp_sdes(
                                            pjmedia_rtcp_session *session, 
                                            void *buf,
                                            pj_size_t *length,
                                            const pjmedia_rtcp_sdes *sdes);

/**
 * Build an RTCP BYE packet. This packet can be appended to other RTCP
 * packets, e.g: RTCP RR/SR, to compose a compound RTCP packet.
 *
 * @param session   The RTCP session.
 * @param buf       The buffer to receive RTCP BYE packet.
 * @param length    On input, it will contain the buffer length.
 *                  On output, it will contain the generated RTCP BYE
 *                  packet length.
 * @param reason    Optional, the BYE reason.
 *
 * @return          PJ_SUCCESS on success.
 */
PJ_DECL(pj_status_t) pjmedia_rtcp_build_rtcp_bye(
                                            pjmedia_rtcp_session *session, 
                                            void *buf,
                                            pj_size_t *length,
                                            const pj_str_t *reason);


/**
 * Call this function if RTCP XR needs to be enabled/disabled in the 
 * RTCP session.
 *
 * @param session   The RTCP session.
 * @param enable    Enable/disable RTCP XR.
 *
 * @return          PJ_SUCCESS on success.
 */
PJ_DECL(pj_status_t) pjmedia_rtcp_enable_xr( pjmedia_rtcp_session *session, 
                                             pj_bool_t enable);


/**
 * @}
 */

PJ_END_DECL


#endif  /* __PJMEDIA_RTCP_H__ */
