. "$BST_LIB"
# nicstat is the third rate tool on this image and the only one whose interval
# form means anything here. procps (85-procps.test) answers "what is the system
# doing now"; sysstat (85-sysstat.test) reads /proc twice and divides, but its
# second sample comes from alarm(2)+pause(2), which returns AT ONCE on this
# kernel (linux-in-the-browser#120), so every sysstat rate is divided by a ~0 s
# window. nicstat sleeps in poll(NULL, 0, ms) instead, and THAT works -- so
# `nicstat 1 3` really does take two seconds and really does report per-second
# rates. nicstat/interval-elapses below is the case that says so, and it is the
# reason this suite sits beside sysstat's rather than with the network tools.
#
# Two things about this machine shape every case here:
#
#   - IT HAS EXACTLY ONE INTERFACE, lo, and no net hardware (the same finding
#     60-net-tools.test records). So `nicstat -n` (non-local only) has nothing to
#     report, and %Util/IErr/OErr/Coll can never be anything but zero.
#   - nicstat SKIPS ANY INTERFACE THAT HAS NEVER SEEN A PACKET, and exits 2
#     "no matching interface" when that leaves nothing. On a freshly booted
#     machine lo's counters are all zero, so a bare `nicstat` fails until
#     something has used the loopback. That is stock nicstat behaviour, not a
#     wasm32 effect -- and it is why this suite generates its own traffic first
#     rather than assuming an earlier suite left some.
#
# No busybox applet is named nicstat and the recipe registers no
# update-alternatives link, so /usr/bin/nicstat can only be this port; the
# version string is asserted anyway because it is free.
#
# A note on shape: a nicstat start-up costs about a second of wasm instantiation
# and the runner bounds a suite at 60 s, so where several cases read the same
# report this file CAPTURES ONCE and asserts several times, rather than paying
# for one invocation per assertion.
require nicstat nicstat/present

# check_fail <id> <want-rc> <needle> <cmd...> -- an error case is only right when
# the exit status and the diagnostic both are; check_out cannot express it
# (it requires rc 0). nicstat's die() exits 2, its usage() exits 1.
check_fail() {
  _id=$1; _want=$2; _needle=$3; shift 3
  _out=$("$@" 2>&1); _rc=$?
  case "$_out" in *"$_needle"*) _hit=1 ;; *) _hit=0 ;; esac
  if [ "$_rc" -eq "$_want" ] && [ "$_hit" -eq 1 ]; then bst_ok "$_id"
  else bst_notok "$_id" "rc=$_rc want=$_want needle:'$_needle' got:'$(_bst_1line "$_out")'"; fi
}

# has <id> <needle> <text> -- assert a captured report contains a literal.
has() {
  case "$3" in *"$2"*) bst_ok "$1" ;;
  *) bst_notok "$1" "no '$2' in: $(_bst_1line "$3")" ;; esac
}

# --- give lo something to count ----------------------------------------------
# Three big echoes rather than many small ones: the byte counter is what the rate
# cases below divide by uptime, and ping paces itself at one packet a second, so
# size is free where count is not. The reply is counted on lo in BOTH directions,
# which is why the rx and tx columns match throughout this suite.
ping -c 3 -s 60000 -W 1 127.0.0.1 >/dev/null 2>&1
# /proc/net/dev's lo row with the "  lo:" label stripped, so $1 is rx bytes and
# $2 is rx packets whatever the leading whitespace does to field splitting.
_lo=$(awk '/^ *lo:/ {sub(/^[^:]*:/, ""); print $1, $2}' /proc/net/dev)
_bytes=${_lo% *}; _pkts=${_lo#* }
if [ "${_pkts:-0}" -gt 0 ] 2>/dev/null; then bst_ok nicstat/traffic-seeded
else bst_notok nicstat/traffic-seeded "lo still shows 0 rx packets in /proc/net/dev after the ping ('$_lo'); every case below is measuring nothing"; fi

# --- identity ----------------------------------------------------------------
check_eq  nicstat/path    /usr/bin/nicstat "$(command -v nicstat)"
check_out nicstat/version "nicstat version 1.95" nicstat -v

# --- the default report ------------------------------------------------------
_full=$(nicstat 2>&1)
has nicstat/header "%Util" "$_full"
# Exactly one data row, and it is lo. The count is exact because the interface
# inventory is: lo.
check_eq nicstat/lo-row 1 "$(printf '%s\n' "$_full" | awk '$2 == "lo" {n++} END {print n+0}')"

# The numbers come off /proc/net/dev rather than being zero placeholders: after
# the burst above, both the byte rate and the packet rate are > 0.
_rates=$(printf '%s\n' "$_full" | awk '$2 == "lo" {print $3, $5}')
if [ -n "$_rates" ] && printf '%s\n' "$_rates" | awk '{exit !($1 > 0 && $2 > 0)}'; then
  bst_ok nicstat/counters-nonzero
else bst_notok nicstat/counters-nonzero "rKB/s and rPk/s were '$_rates', want both > 0"; fi

# The first sample is SINCE BOOT -- rate = counter / uptime, with no second
# sample involved -- so it can be recomputed from the two files nicstat read.
# Agreement inside a factor of two is the assertion (the two reads are a second
# or so apart and lo keeps ticking); that band is what distinguishes "divided by
# the right clock" from "divided by whatever tv_sec happened to hold".
_want=$(awk -v b="$_bytes" -v u="$(awk '{print $1}' /proc/uptime)" 'BEGIN {print b / 1024 / u}')
_got=$(printf '%s\n' "$_full" | awk '$2 == "lo" {print $3}')
if [ -n "$_got" ] && awk -v w="$_want" -v g="$_got" 'BEGIN {exit !(w > 0 && g > 0 && g < w*2 && g > w/2)}'; then
  bst_ok nicstat/since-boot-rate
else bst_notok nicstat/since-boot-rate "nicstat rKB/s=$_got, /proc/net/dev over /proc/uptime=$_want (want within 2x)"; fi

# --- the other report styles -------------------------------------------------
check_out nicstat/extended  "IErr  OErr  Coll" nicstat -x
check_out nicstat/mbit      "rMbps"            nicstat -M
check_out nicstat/util-both "%rUtil %wUtil"    nicstat -U
# -s is the same two rates at %14.3f, so the fixed three decimals are what
# identify it -- "rKB/s" alone is in the default header too.
_sum=$(nicstat -s 2>/dev/null | awk '$2 == "lo" {print $3}')
if awk -v v="$_sum" 'BEGIN {exit !(v ~ /^[0-9]+\.[0-9][0-9][0-9]$/)}'; then bst_ok nicstat/summary
else bst_notok nicstat/summary "summary rKB/s is not a 3-decimal number: '$_sum'"; fi

# -l is the inventory rather than a report. It knows lo is a loopback
# (NIC_LOOPBACK, set from the interface name in /proc/net/dev), which is what
# makes it print "-" for the speed instead of a bogus 0 Mbit/s, and with no -S
# given it has no duplex to report either.
_list=$(nicstat -l 2>&1)
has nicstat/list "Int      Loopback   Mbit/s Duplex State" "$_list"
check_eq nicstat/list-loopback "Yes - unkn up" \
  "$(printf '%s\n' "$_list" | awk '$1 == "lo" {print $2, $3, $4, $5}')"

# --- parseable output: the one form a script consumes ------------------------
# This is where the port's single source fix lives. Every parseable line leads
# with tv_sec, which upstream prints as %ld -- correct only where long is as wide
# as time_t. Here long is 4 bytes and time_t is 8, so printf consumed half the
# timestamp and every later conversion read the wrong slot: the name came out
# "(null)" off the timestamp's high half and each %.*f drew a garbage precision,
# printing one rate with several hundred fraction digits. The three cases below
# assert the three symptoms separately, so a regression names itself.
_p=$(nicstat -p 2>/dev/null | grep ':lo:' | head -1)
check_eq nicstat/parseable-fields 8 "$(printf '%s\n' "$_p" | awk -F: '{print NF}')"
# Field 1 is a ten-digit epoch, not a truncated or garbled one.
if printf '%s\n' "$_p" | awk -F: '{exit !(length($1) == 10 && $1 ~ /^[0-9]+$/)}'; then bst_ok nicstat/parseable-epoch
else bst_notok nicstat/parseable-epoch "field 1 is not a 10-digit epoch: '$(_bst_1line "$_p")'"; fi
# ...and every rate field carries at most three decimals (precision_p's maximum).
if printf '%s\n' "$_p" | awk -F: '{for (i = 3; i <= NF; i++) if ($i !~ /^[0-9]+\.[0-9][0-9]?[0-9]?$/) exit 1; exit 0}'; then
  bst_ok nicstat/parseable-precision
else bst_notok nicstat/parseable-precision "a rate field is not a <=3-decimal number: '$(_bst_1line "$_p")'"; fi

# --- the /proc/net/snmp and /proc/net/netstat readers ------------------------
# -t and -u are a different data source from everything above: nicstat parses the
# Tcp:/Udp: lines of /proc/net/snmp by their exact column-header text, and -t also
# reads TcpExt: out of /proc/net/netstat. A kernel that laid those files out
# differently would print a row of zeros here rather than failing, so the
# parseable forms -- which carry the field count and the timestamp -- are asserted
# alongside the human ones.
check_out nicstat/tcp "InSeg  OutSeg" nicstat -t
check_out nicstat/udp "InDG   OutDG"  nicstat -u
# One capture covers four things at once, which is also the cheapest way to prove
# the -a alias really is "-x -u -t": with -p it emits the TCP line, the UDP line
# AND the extended-parseable interface line, so asserting all three field counts
# says the alias set every flag it documents.
_a=$(nicstat -a -p 2>&1)
check_eq nicstat/all-tcp 12 "$(printf '%s\n' "$_a" | grep ':TCP:' | head -1 | awk -F: '{print NF}')"
check_eq nicstat/all-udp  6 "$(printf '%s\n' "$_a" | grep ':UDP:' | head -1 | awk -F: '{print NF}')"
check_eq nicstat/all-extended 13 "$(printf '%s\n' "$_a" | grep ':lo:' | head -1 | awk -F: '{print NF}')"
# The InSeg field is a well-formed rate rather than the garbage the %ld bug
# produced. It is asserted for SHAPE, not for a non-zero value: nothing on this
# machine is obliged to have opened a TCP connection by the time this suite runs
# (the ping above is ICMP), so a legitimate 0.000 must stay green.
_seg=$(printf '%s\n' "$_a" | grep ':TCP:' | head -1 | awk -F: '{print $5}')
if awk -v s="$_seg" 'BEGIN {exit !(s ~ /^[0-9]+\.[0-9][0-9]?[0-9]?$/)}'; then bst_ok nicstat/tcp-counters
else bst_notok nicstat/tcp-counters "InSeg field is not a <=3-decimal number: '$_seg'"; fi

# --- interface selection -----------------------------------------------------
# -i takes a comma list; an unknown name in it is simply not matched, while an
# -i that matches nothing at all is the die() path.
check_eq nicstat/select-if 1 "$(nicstat -i lo,nosuchif 2>/dev/null | awk '$2 == "lo" {n++} END {print n+0}')"
check_fail nicstat/select-none 2 "no matching interface" nicstat -i nosuchif
# -n excludes loopback, and loopback is all this machine has. This is the same
# g_nicdata_count <= 0 exit a freshly booted machine gives for a bare nicstat,
# reached deterministically -- so it covers the boot-state contract described at
# the top of this file without depending on how much traffic has already run.
check_fail nicstat/nonlocal-none 2 "no matching interface" nicstat -n

# --- -S, the Linux-only speed override ---------------------------------------
# lo answers no SIOCETHTOOL, so get_speed_duplex() sets NIC_NO_GSET and falls back
# to the -S list. The duplex column flipping from the "unkn" asserted above to
# "full" (and to "half" for a :NNNhd record) is the proof that both halves of that
# path ran: the ioctl failure was handled, and the list was parsed, matched by
# interface name, and its duplex suffix decoded.
check_eq nicstat/speed-flag-full "full" \
  "$(nicstat -S lo:1000fd -l 2>/dev/null | awk '$1 == "lo" {print $4}')"
check_eq nicstat/speed-flag-half "half" \
  "$(nicstat -S lo:100hd -l 2>/dev/null | awk '$1 == "lo" {print $4}')"

# --- error contracts ---------------------------------------------------------
# usage() exits 1 and prints to stderr; die() exits 2. Both statuses are part of
# the CLI contract for a script that drives this tool.
check_fail nicstat/usage        1 "USAGE: nicstat" nicstat -h
check_fail nicstat/bad-option   1 "invalid option" nicstat -Q
check_fail nicstat/bad-interval 1 "USAGE: nicstat" nicstat 0

# --- the interval form, which is the whole point of a rate tool --------------
# One run, two assertions: three samples (the since-boot one plus two computed
# over a real elapsed second), and >= 2 s of wall clock to produce them. The
# second is what separates nicstat from sysstat on this machine: sysstat's
# alarm(2)+pause(2) returns at once and its `sar -u 1 3` finishes in about a
# second with every rate divided by ~0, while nicstat's poll(NULL, 0, ms) blocks
# for the interval it was given. If poll ever regresses to the same immediate
# return, nicstat/interval-elapses goes red and nicstat/interval-samples stays
# green -- exactly the split that says the rates became meaningless while the
# output shape did not.
_s=$(date +%s); _iv=$(nicstat 1 3 2>&1); _e=$(date +%s)
check_eq nicstat/interval-samples 3 "$(printf '%s\n' "$_iv" | awk '$2 == "lo" {n++} END {print n+0}')"
_el=$((_e - _s))
if [ "$_el" -ge 2 ]; then bst_ok nicstat/interval-elapses
else bst_notok nicstat/interval-elapses "\`nicstat 1 3\` took ${_el}s, want >= 2s: poll(NULL,0,ms) is not sleeping, so every interval rate is divided by a ~0s window"; fi

# --- present but not reachable on this machine (attributed, NOT executed as
#     assertions: each would flip on its own if the platform gained the source)
bst_skip nicstat/util-percent \
  "%Util is structurally 0.00 here: it is bytes*800/speed, lo reports no link speed, and even -S lo:1000fd over loopback ping traffic rounds to zero -- the column is asserted present, never non-zero"
bst_skip nicstat/ethtool-speed \
  "the SIOCETHTOOL/ETHTOOL_GSET discovery path cannot be covered: lo answers no ethtool ioctl on any Linux, and this machine has no other interface. Its FALLBACK is covered by nicstat/speed-flag-full"
bst_skip nicstat/nonlocal-interfaces \
  "-n's reporting mode needs a non-loopback interface and this machine has none (no virtio-net; 60-net-tools.test records the same). Its error contract is asserted by nicstat/nonlocal-none"
bst_skip nicstat/error-columns \
  "IErr/OErr/Coll/NoCP/Defer are always 0 on lo -- there is no hardware here to drop, collide or defer a frame, so the -x columns can be asserted present but never exercised"
bst_skip nicstat/man-page \
  "nicstat.1 is packaged into nicstat-doc and this image installs no -doc packages"