#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>  /* struct sockaddr_in */
#include <arpa/inet.h>   /* inet_ntoa() */
#include <sys/time.h>    /* gettimeofday() */
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <netdb.h>
#include <unistd.h>      /* select(), perror() */
#include "raw_rtp.h"
#include "ansi.h"
#include "sysdep.h"

void member_sdes(source* s, rtcp_sdes_type_t t, char *b, int len);
/*
 *  This function builds one SDES chunk into buffer b composed of argc
 *  items supplied in arrays type , value and length b
 *
 *
 *  0                   1                   2                   3
 *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 *  |V=2|P|    SC   |  PT=SDES=202  |             length            | header
 *  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
 *  |                          SSRC/CSRC_1                          | chunk
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   1
 *  |                           SDES items                          |
 *  |                              ...                              |
 *  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
 *  |                          SSRC/CSRC_2                          | chunk
 *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+   2
 *  |                           SDES items                          |
 *  |                              ...                              |
 *  +=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
 */

char *rtp_write_sdes(char *b, u_int32 src, int argc,
		     rtcp_sdes_type_t type[], char *value[],
		     int length[])
{
    /* source description (SDES) 
     *   struct rtcp_sdes {
     *    u_int32 src;   
     *    rtcp_sdes_item_t item[1]; 
     *  } sdes;
     * 
     *  typedef struct rtcp_sdes rtcp_sdes_t;
     */

  rtcp_sdes_t *s = (rtcp_sdes_t *)b;
  rtcp_sdes_item_t *rsp;
  int i;
  int len;
  int pad;
  
  /* SSRC header */
  s->src = src;
  rsp = &s->item[0];
  
  /* SDES items */
  for (i = 0; i < argc; i++) {
    rsp->type = type[i];
    len = length[i];
    if (len > RTP_MAX_SDES) {
      /* invalid length, may want to take other action */
      len = RTP_MAX_SDES;
    }
    rsp->length = len;
    memcpy(rsp->data, value[i], len);
    rsp = (rtcp_sdes_item_t *)&rsp->data[len];
  }
  
  /* terminate with end marker and pad to next 4-octet boundary */
  len = ((char *) rsp) - b;
  pad = 4 - (len & 0x3);
  b = (char *) rsp;
  while (pad--) *b++ = RTCP_SDES_END;
  
  return b;
}


/* Parsing RTCP SDES Packets
 *
 * This function parses an SDES packet, calling functions find_member()
 * to find a pointer to the information for a session member given the
 * SSRC identifier and member_sdes() to store the new SDES information
 * for that member. This function expects a pointer to the header of the
 * RTCP packet.
 */

/* void rtp_read_sdes(rtcp_t *r, source *s)
 *{
 *  int count = r->common.count;
 * rtcp_sdes_t *sd = &r->r.sdes;
 * rtcp_sdes_item_t *rsp, *rspn;
 * rtcp_sdes_item_t *end = (rtcp_sdes_item_t *)
 *
 *  ((u_int32 *)r + r->common.length + 1);
 *
 *  
 * while (--count >= 0) {
 *  rsp = &sd->item[0];
 *  if (rsp >= end) break;
 *
 *
 *  for (; rsp->type; rsp = rspn ) {
 *    rspn = (rtcp_sdes_item_t *)((char*)rsp+rsp->length+2);
 *    if (rspn >= end) {
 *      rsp = rspn;
 *	break;
 *    }
 *    member_sdes(s, rsp->type, rsp->data, rsp->length);
 *  }
 *  sd = (rtcp_sdes_t *)
 *    ((u_int32 *)sd + (((char *)rsp - (char *)sd) >> 2)+1);
 *}
 * if (count >= 0) {
 *
 *}
 *}
*/
static char *rtp_read_sdes(char *b, int len)
{
  rtcp_sdes_item_t *rsp;
  u_int32 src = *(u_int32 *)b;
  int total_len = 0;

  len -= 4;  /* subtract SSRC from available bytes */
  if (len <= 0) {
    return 0;
  }
  rsp = (rtcp_sdes_item_t *)(b + 4);
  for (; rsp->type; rsp = (rtcp_sdes_item_t *)((char *)rsp + rsp->length + 2)) {
    member_sdes(src, rsp->type, rsp->data, rsp->length);
    total_len += rsp->length + 2;
  }
  if (total_len >= len) {
	fprintf(stderr, 
      "Remaining length of %d bytes for SSRC item too short (has %u bytes)\n",
      len, total_len);
    return 0;
  }
  b = (char *)rsp + 1;
  /* skip padding */
  return b + ((4 - ((int)b & 0x3)) & 0x3);
} /* rtp_read_sdes */

void member_sdes(source* s, rtcp_sdes_type_t t, char *b, int len)
{
  static struct {
    rtcp_sdes_type_t t;
    char *name;
  } map[] = {
    {RTCP_SDES_END,    "end"}, 
    {RTCP_SDES_CNAME,  "CNAME"},
    {RTCP_SDES_NAME,   "NAME"},
    {RTCP_SDES_EMAIL,  "EMAIL"},
    {RTCP_SDES_PHONE,  "PHONE"},
    {RTCP_SDES_LOC,    "LOC"},
    {RTCP_SDES_TOOL,   "TOOL"},
    {RTCP_SDES_NOTE,   "NOTE"},
    {RTCP_SDES_PRIV,   "PRIV"},
    {11,               "SOURCE"},
    {0,0}
  };
  int i;
  char num[10];

  sprintf(num, "%d", t);
  for (i = 0; map[i].name; i++) {
    if (map[i].t == t) break;
  }
  printf("%s=\"%*.*s\" ",
    map[i].name ? map[i].name : num, len, len, b);
} /* member_sdes */

/*
* Return length parsed, -1 on error.
*/
static int parse_control(char *buf, int len)
{
  rtcp_t *r;         /* RTCP header */
  int i;

  r = (rtcp_t *)buf;
  if (r->common.version == RTP_VERSION) {
    printf("\n");
    while (len > 0) {
      len -= (ntohs(r->common.length) + 1) << 2;
      if (len < 0) {
        /* something wrong with packet format */
        printf("Illegal RTCP packet length %d words.\n",
	       ntohs(r->common.length));
        return -1;
      }

      switch (r->common.pt) {
      case RTCP_SR:
        printf(" (SR ssrc=0x%lx p=%d count=%d len=%d\n", 
          (unsigned long)ntohl(r->r.rr.ssrc),
          r->common.p, r->common.count,
	      ntohs(r->common.length));
        printf("ntp=%lu.%lu ts=%lu psent=%lu osent=%lu\n",
          (unsigned long)ntohl(r->r.sr.ntp_sec),
          (unsigned long)ntohl(r->r.sr.ntp_frac),
          (unsigned long)ntohl(r->r.sr.rtp_ts),
          (unsigned long)ntohl(r->r.sr.psent),
          (unsigned long)ntohl(r->r.sr.osent));
        for (i = 0; i < r->common.count; i++) {
          printf("  (ssrc=%0lx fraction=%g lost=%lu last_seq=%lu jit=%lu lsr=%lu dlsr=%lu)\n",
           (unsigned long)ntohl(r->r.sr.rr[i].ssrc),
           r->r.sr.rr[i].fraction / 256.,
           (unsigned long)ntohl(r->r.sr.rr[i].lost), /* XXX I'm pretty sure this is wrong */
           (unsigned long)ntohl(r->r.sr.rr[i].last_seq),
           (unsigned long)ntohl(r->r.sr.rr[i].jitter),
           (unsigned long)ntohl(r->r.sr.rr[i].lsr),
           (unsigned long)ntohl(r->r.sr.rr[i].dlsr));
        }
        printf(" )\n"); 
        break;

      case RTCP_RR:
        printf(" (RR ssrc=0x%lx p=%d count=%d len=%d\n", 
          (unsigned long)ntohl(r->r.rr.ssrc), r->common.p, r->common.count,
	      ntohs(r->common.length));
        for (i = 0; i < r->common.count; i++) {
          printf("(ssrc=%0lx fraction=%g lost=%lu last_seq=%lu jit=%lu lsr=%lu dlsr=%lu)\n",
            (unsigned long)ntohl(r->r.rr.rr[i].ssrc),
            r->r.rr.rr[i].fraction / 256.,
            (unsigned long)ntohl(r->r.rr.rr[i].lost),
            (unsigned long)ntohl(r->r.rr.rr[i].last_seq),
            (unsigned long)ntohl(r->r.rr.rr[i].jitter),
            (unsigned long)ntohl(r->r.rr.rr[i].lsr),
            (unsigned long)ntohl(r->r.rr.rr[i].dlsr));
        }
        printf(" )\n"); 
        break;

      case RTCP_SDES:
        printf(" (SDES p=%d count=%d len=%d\n", 
          r->common.p, r->common.count, ntohs(r->common.length));
        buf = (char *)&r->r.sdes;
        for (i = 0; i < r->common.count; i++) {
          int remaining = (ntohs(r->common.length) << 2) -
	    (buf - (char *)&r->r.sdes);

          printf("  (src=0x%lx ", 
            (unsigned long)ntohl(((struct rtcp_sdes *)buf)->src));
          if (remaining > 0) {
            buf = rtp_read_sdes(buf, 
              (ntohs(r->common.length) << 2) - (buf - (char *)&r->r.sdes));
            if (!buf) return -1;
          }
          else {
            fprintf(stderr, "Missing at least %d bytes.\n", -remaining);
            return -1;
          }
          printf(")\n"); 
        }
        printf(" )\n"); 
        break;

      case RTCP_BYE:
        printf(" (BYE p=%d count=%d len=%d\n", 
          r->common.p, r->common.count, ntohs(r->common.length));
        for (i = 0; i < r->common.count; i++) {
          printf("ssrc[%d]=%0lx ", i, 
            (unsigned long)ntohl(r->r.bye.src[i]));
        }
        if (ntohs(r->common.length) > r->common.count) {
          buf = (char *)&r->r.bye.src[r->common.count];
          printf("reason=\"%*.*s\"", *buf, *buf, buf+1); 
        }
        printf(")\n");
        break;

      /* invalid type */
      default:
        printf("(? pt=%d src=0x%lx)\n", r->common.pt, 
          (unsigned long)ntohl(r->r.sdes.src));
      break;
      }
      r = (rtcp_t *)((u_int32 *)r + ntohs(r->common.length) + 1);
    }
  }
  else {
    printf("invalid version %d\n", r->common.version);
  }
  return len;
} /* parse_control */