. "$BST_LIB"
require htop htop/present

# htop is a CURSES program with no batch mode, and the option that makes it
# testable at all is -n/--max-iterations: ScreenManager.c decrements the counter
# immediately after drawing a frame and quits BEFORE the first Panel_getCh(), so
# `htop -n 1` renders one frame and exits without ever reading a key. Every frame
# case below therefore runs with stdin on /dev/null and cannot block on input --
# which matters here because the runner is typed onto the guest's own tty, and a
# tool that waited for a keystroke would wedge the whole sweep rather than just
# this suite.
#
# -C (monochrome) and -U (plain ASCII) keep the escape traffic down to cursor
# motion, which is what lets the needles below survive as CONTIGUOUS substrings
# of the raw capture; "Mem[" and the function-key bar do not survive and are not
# used. TERM/LINES/COLUMNS are pinned so the frame is the same shape wherever it
# runs, and the 200-column width is what puts a whole command line in the Command
# column instead of a truncation.
#
# THE WHOLE-/proc WALK IS THE RISK ON THIS ARM, NOT THE CURSES LAYER. procps'
# top, vmstat, pgrep and full `ps -e` hang here on brintos/linux#9 (/proc reads
# return EINTR and are not restarted) and 85-procps.test records them as skips
# WITHOUT running them; psmisc's pstree/fuser walk the same /proc and are clean
# 8/8, so the class is not "any scan hangs". htop is measured rather than
# assumed: the CLI cases below touch no /proc at all and come FIRST, so they are
# emitted even if a later frame case runs into the suite bound.

htop_out=""; htop_rc=0
# hrun <htop args...> : one frame, stdin closed, pinned geometry. Sets
# $htop_out (raw capture) and $htop_rc.
hrun() {
  htop_out=$(TERM=xterm LINES=40 COLUMNS=200 HOME="$hhome" htop "$@" </dev/null 2>&1)
  htop_rc=$?
}
# hdetail : the capture with the escape traffic stripped, for a failure detail.
hdetail() { printf '%s' "$htop_out" | tr -cd '\11\12\40-\176' | tr '\n\t' '  ' | cut -c1-100; }
# hrcout <id> <want-rc> <needle> <cmd...> : ok iff <cmd> exits <want-rc> AND says
# <needle>. check_out cannot express this -- it requires rc 0 as well as the
# needle -- and every refusal htop has is a non-zero status carrying the message
# that explains it, so asserting the two separately would leave the message
# unchecked or the status unasserted.
hrcout() {
  _id=$1; _want=$2; _needle=$3; shift 3
  _o=$("$@" 2>&1); _r=$?
  case "$_o" in *"$_needle"*) _h=1 ;; *) _h=0 ;; esac
  if [ "$_r" -eq "$_want" ] && [ "$_h" -eq 1 ]; then bst_ok "$_id"
  elif bst_execfail "$_o"; then bst_unrun "$_id" "$_o"
  else bst_notok "$_id" "rc=$_r want=$_want needle:'$_needle' got:'$(_bst_1line "$_o")'"; fi
}
# hframe <id> <needle> <htop args...> : ok iff the frame exits 0 and carries the needle.
hframe() {
  _id=$1; _needle=$2; shift 2
  hrun "$@"
  case "$htop_out" in *"$_needle"*) _hit=1 ;; *) _hit=0 ;; esac
  if [ "$htop_rc" -eq 0 ] && [ "$_hit" -eq 1 ]; then bst_ok "$_id"
  elif bst_execfail "$htop_out"; then bst_unrun "$_id" "$htop_out"
  else bst_notok "$_id" "rc=$htop_rc want:'$_needle' got:'$(hdetail)'"; fi
}

hhome=${TMPDIR:-/tmp}/bst-htop.$$
mkdir -p "$hhome"

# --- 1. the CLI surface: no terminal, no /proc ------------------------------
# --version and --help answer out of CommandLine.c before Platform_init(), and
# --sort-key=help walks the static column table and exits from inside getopt
# processing. None of the three opens /proc or initscr(), so they are the cases
# that stay meaningful even where the display cannot be reached at all.
check_out htop/version      "htop 3.3.0"        htop --version
check_out htop/help-iter    "--max-iterations"  htop --help
check_out htop/sortkey-help "PROCESSOR"         htop --sort-key=help

# --- 2. the CLI refusals, which are the only non-zero statuses htop has -----
check_rc  htop/bad-option   1 htop --nosuchopt
check_rc  htop/bad-sortkey  1 htop --sort-key=NOSUCHCOLUMN
check_rc  htop/bad-user     1 htop --user=nosuchuser99
check_rc  htop/bad-iter     1 htop --max-iterations=0
hrcout    htop/bad-sortkey-msg 1 "invalid column" htop --sort-key=NOSUCHCOLUMN
hrcout    htop/bad-user-msg    1 "invalid user"   htop --user=nosuchuser99
hrcout    htop/bad-option-msg  1 "unrecognized option" htop --nosuchopt

# --- 3. one frame: curses came up and the /proc walk completed --------------
# Each needle is a different reader. Tasks: is ProcessTable's own count of what
# the walk collected, Load average: is /proc/loadavg, Uptime: is /proc/uptime,
# and "PID USER" is the column header the table draws once it has rows.
hframe htop/frame-runs    "Tasks:"        -C -U -n 1
hframe htop/frame-load    "Load average:" -C -U -n 1
hframe htop/frame-uptime  "Uptime:"       -C -U -n 1
hframe htop/frame-header  "PID USER"      -C -U -n 1
# kthr is the kernel-thread count in the same Tasks meter -- present only when
# the walk actually distinguished kernel threads, which needs /proc/<pid>/stat
# per process rather than just the directory listing.
hframe htop/frame-kthr    "kthr"          -C -U -n 1

# --- 4. the axes that prove it is reading, not just painting ----------------
# -t adds the ASCII tree drawing (`- with -U); the flat frame has none of it, so
# the needle tells the two renderers apart rather than merely re-asserting a
# frame was drawn.
hframe htop/tree          '`-'            -C -U -n 1 -t
# Two frames means the refresh loop re-read /proc and redrew, which is the shape
# top(1) cannot survive here.
hframe htop/two-frames    "Tasks:"        -C -U -n 2 -d 1
hframe htop/readonly      "Tasks:"        -C -U -n 1 --readonly
hframe htop/sort-pid      "Tasks:"        -C -U -n 1 -s PID

# -p and -F are the two filters, and both are asserted against a string read out
# of /proc at run time rather than a pinned one: this kernel runs no init at all
# (arch/wasm32's boot path ends in run_init_process(/bin/sh)), so pid 1 is the
# shell and any hardcoded "systemd"/"init" would assert a process that does not
# exist here. Same reasoning as 85-procps.test's ps-pid1 case.
cmd1=$(tr '\0' ' ' < /proc/1/cmdline 2>/dev/null | awk '{print $1}')
[ -n "$cmd1" ] || cmd1=$(cat /proc/1/comm 2>/dev/null)
if [ -n "$cmd1" ]; then
  hframe htop/pid-filter  "$cmd1"         -C -U -n 1 -p 1
  hframe htop/comm-filter "$cmd1"         -C -U -n 1 -F "$cmd1"
else
  bst_skip htop/pid-filter  "/proc/1/cmdline and /proc/1/comm are both empty, so there is no name to filter on"
  bst_skip htop/comm-filter "/proc/1/cmdline and /proc/1/comm are both empty, so there is no name to filter on"
fi

# --- 5. the settings writer, which is the only thing htop writes ------------
# htop saves its configuration on exit, creating $HOME/.config/htop/ as it goes.
# It is the one filesystem write in the package and it is silent either way --
# an unwritable HOME still exits 0 -- so nothing but the file itself says whether
# it worked. (--readonly does NOT suppress it: that option disables killing and
# renicing, not persistence.)
if [ -f "$hhome/.config/htop/htoprc" ]; then bst_ok htop/config-write
else bst_notok htop/config-write "no settings file at $hhome/.config/htop/htoprc after the frames above"; fi
# The version stamp is written from the running binary, so this pins the file to
# THIS htop rather than to any htoprc that happened to be lying around.
check_out htop/config-content "htop_version=3.3.0" cat "$hhome/.config/htop/htoprc"

rm -rf "$hhome"