# awk program to scan peerstats files and report errors/statistics
#
# usage: awk -f peer.awk peerstats
#
# format of peerstats record
#  MJD    sec    ident   stat  offset (s)  delay (s)  disp (s)
# 49235 11.632 128.4.2.7 f414  -0.000041    0.21910   0.00084
#
# format of output dataset (time values in milliseconds)
# peerstats.19960706
#        ident     cnt     mean     rms      max     delay     dist     disp
# ==========================================================================
# 140.173.112.2     85   -0.509    1.345    4.606   80.417   49.260    1.092
# 128.4.1.20      1364    0.058    0.364    4.465    3.712   10.540    1.101
# 140.173.16.1    1415   -0.172    0.185    1.736    3.145    5.020    0.312
#...
#
BEGIN {
	n = 0
	MAXDISTANCE = 1.0
}
#
# scan all records in file
#
# we toss out all distances greater than one second on the assumption the
# peer is in initial acquisition
#
{
	if (NF >= 7 && ($7 + $6 / 2) < MAXDISTANCE) {
		i = n
		for (j = 0; j < n; j++) {
			if ($3 == peer_ident[j])
				i = j
		}
		if (i == n) {
			peer_ident[i] = $3
			peer_tmax[i] = peer_dist[i] = -1e9
			peer_tmin[i] = 1e9
			n++
		}
		peer_count[i]++
		if ($5 > peer_tmax[i])
			peer_tmax[i] = $5
		if ($5 < peer_tmin[i])
			peer_tmin[i] = $5
		dist = $7 + $6 / 2
		if (dist > peer_dist[i])
			peer_dist[i] = dist
		peer_time[i] += $5
		peer_time_rms[i] += $5 * $5
		peer_delay[i] += $6
		peer_disp[i] +=  $7
	}
} END {
	printf "       ident     cnt     mean     rms      max     delay     dist     disp\n"
	printf "==========================================================================\n"
	for (i = 0; i < n; i++) {
		peer_time[i] /= peer_count[i]
                peer_time_rms[i] = sqrt(peer_time_rms[i] / peer_count[i] - peer_time[i] * peer_time[i])
		peer_delay[i] /= peer_count[i]
		peer_disp[i] /= peer_count[i]
		peer_tmax[i] = peer_tmax[i] - peer_time[i]
		peer_tmin[i] = peer_time[i] - peer_tmin[i]
		if (peer_tmin[i] > peer_tmax[i])
			peer_tmax[i] = peer_tmin[i]
		printf "%-15s%5d%9.3f%9.3f%9.3f%9.3f%9.3f%9.3f\n", peer_ident[i], peer_count[i], peer_time[i] * 1e3, peer_time_rms[i] * 1e3, peer_tmax[i] * 1e3, peer_delay[i] * 1e3, peer_dist[i] * 1e3, peer_disp[i] * 1e3
	}
}