#!/usr/bin/env bash
# tools/hw_probe.sh — what device context exists RIGHT NOW. It informs; it does
# not gate. Always exits 0, and .agents/validate.sh deliberately does NOT fold
# its exit status into the gate's rc.
#
# Why this exists (AGENTS.md "Verification standard", PLAN.md "No unit blocks on
# hardware"): device checks are the half of this roadmap's verification the host
# gate cannot see. They are best effort — one attempt, wrapped in a timeout, the
# outcome recorded in .agents/HW_VERIFICATION.md. This probe is the cheap way to
# find out whether attempting one is even plausible, so a unit running unattended
# never discovers the absence of a board by hanging on it.
#
# Rules this script obeys — the same rules the hardware contract states:
#   * No side effects. It writes nothing and NEVER opens a serial port: opening
#     /dev/ttyACM* asserts DTR/RTS and resets the board. `test -e`/`test -r` and
#     read-only sysfs metadata only. HTTP(S) probes are idempotent GETs.
#   * Never blocks. Every probe that could wait is capped with `timeout` or curl
#     -m. getent CAN hang when no mDNS responder answers, so it runs only under
#     `timeout` — if `timeout` itself is missing, the lookup is skipped with a
#     stated reason rather than risked.
#   * Always exits 0. Every fact is printed; none of them is a verdict. The
#     gate result comes from .agents/validate.sh; device verdicts come from the
#     outcome table in .agents/HW_VERIFICATION.md, filled in by whoever ran the
#     actual command — never inferred from these lines.
#
# One line per fact, prefix "hw-probe", so the output stays greppable:
#   serial nodes / keyrelay.local resolution / https / http(+redirect) /
#   uv / node / watch_target.py-capable evdev nodes.
set -uo pipefail

have() { command -v "$1" >/dev/null 2>&1; }

# to <secs> <cmd...> — run capped; rc 124 = the cap fired, 125 = cannot cap, so
# the caller must NOT run the command (an uncapped blocking probe is exactly
# what this file's rule forbids).
to() {
  local secs="$1"
  shift
  if have timeout; then
    timeout "$secs" "$@"
  else
    return 125
  fi
}

# --- 1. serial nodes (existence and readability ONLY — never opened) ----------
serials=()
for candidate in /dev/ttyACM* /dev/ttyUSB*; do
  [[ -e "$candidate" ]] && serials+=("$candidate")
done
if ((${#serials[@]} > 0)); then
  for s in "${serials[@]}"; do
    if [[ -r "$s" ]]; then
      echo "hw-probe serial   $s present, readable  (NOT opened: opening toggles DTR/RTS and resets the board)"
    else
      echo "hw-probe serial   $s present, NOT readable (serial group membership? console.py would fail)"
    fi
  done
else
  echo "hw-probe serial   no /dev/ttyACM* or /dev/ttyUSB* here — no board on a serial port"
fi

# --- 2. keyrelay.local (mDNS via the resolver; may legitimately be slow) ------
mdns_rc=0
mdns_out="$(to 4 getent hosts keyrelay.local 2>/dev/null)" || mdns_rc=$?
if ! have getent && ((mdns_rc != 0)); then
  echo "hw-probe mdns     unknown — getent not installed; resolution state not checkable here"
elif ((mdns_rc == 0)); then
  echo "hw-probe mdns     keyrelay.local resolves -> ${mdns_out%%[[:space:]]*}"
elif ((mdns_rc == 124)); then
  echo "hw-probe mdns     keyrelay.local did not resolve within 4 s (no responder? glibc does not cache mDNS — a retry may still work; the IP is the fallback)"
elif ((mdns_rc == 125)); then
  echo "hw-probe mdns     unknown — 'timeout' is not installed and an uncapped resolver lookup can hang; skipped on principle"
else
  echo "hw-probe mdns     keyrelay.local did not resolve"
fi

# --- 3./4. reachability of the two listeners -----------------------------------
# Expectations shift when phase 02 lands: until then :80 serves the page and
# :443 is closed; after it, :443 serves TLS and :80 is redirect-only. Both
# halves print what IS, and name the expectation, so neither state reads as a
# failure — this probe cannot fail, only inform.
if have curl; then
  https_rc=0
  https_code="$(curl -sk -m 2 -o /dev/null -w '%{http_code}' https://keyrelay.local/ 2>/dev/null)" || https_rc=$?
  if [[ "$https_rc" == 0 && "$https_code" != 000 ]]; then
    echo "hw-probe https    https://keyrelay.local/ -> HTTP $https_code (TLS listener is up)"
  else
    echo "hw-probe https    https://keyrelay.local/ unreachable (curl rc $https_rc, code ${https_code:-000}) — expected until phase 02 (TLS) lands"
  fi

  http_rc=0
  http_fact="$(curl -s -m 2 -o /dev/null -w '%{http_code} %{redirect_url}' http://keyrelay.local/ 2>/dev/null)" || http_rc=$?
  http_code="${http_fact%% *}"
  http_redirect="${http_fact#* }"
  if [[ "$http_rc" == 0 && "$http_code" == 3* && -n "$http_redirect" ]]; then
    echo "hw-probe http     http://keyrelay.local/ -> HTTP $http_code, redirects to $http_redirect (redirect-only: the post-phase-02 shape)"
  elif [[ "$http_rc" == 0 && "$http_code" != 000 ]]; then
    echo "hw-probe http     http://keyrelay.local/ -> HTTP $http_code, no redirect (plaintext page still served: the pre-phase-02 shape)"
  else
    echo "hw-probe http     http://keyrelay.local/ unreachable (curl rc $http_rc) — board off, asleep, or this host is not on its network"
  fi
else
  echo "hw-probe http     skipped — curl not installed; https/http reachability unknown"
fi

# --- 5./6. the two tools the gate and the suites pin ---------------------------
if have uv; then
  echo "hw-probe uv       $(command -v uv) — firmware builds available"
else
  echo "hw-probe uv       MISSING — the gate's firmware check will FAIL (AGENTS.md: pio on PATH is broken; fallback probe: find / -maxdepth 6 -name platformio -type d -path '*site-packages*')"
fi
if have node; then
  echo "hw-probe node     $(command -v node) — test_page.js runs"
else
  echo "hw-probe node     MISSING — tests/run_tests.sh would skip the page suite and the gate pins it; the gate will FAIL"
fi

# --- 7. watch_target.py-capable evdev nodes (informational, read-only) ---------
# Same discovery rule watch_target.py uses: USB devices with the board's ids
# (Logitech G815 identity, Espressif default accepted), nodes classified by the
# kernel's capabilities/ev mask, never by node order — the same reasoning that
# keeps the verifier honest. sysfs reads only; no /dev/input node is opened.
kb=""
ms=""
board_ids=""
for dev in /sys/bus/usb/devices/*/; do
  [[ -r "${dev}idVendor" && -r "${dev}idProduct" ]] || continue
  vid="$(<"${dev}idVendor")"
  pid="$(<"${dev}idProduct")"
  case "$vid:$pid" in
  046d:c33f | 303a:1001) : ;;
  *) continue ;;
  esac
  for ev in "$dev"*/input/input*/event* "$dev"*/*/input/input*/event*; do
    [[ -e "$ev" ]] || continue
    caps_file="${ev%/*}/capabilities/ev" # built-in, not `dirname` — works with any PATH
    [[ -r "$caps_file" ]] || continue
    mask_hex="$(<"$caps_file")"
    [[ "$mask_hex" =~ ^[0-9a-fA-F]+$ ]] || continue
    mask=$((16#$mask_hex))
    node="/dev/input/${ev##*/}"
    readable="readable"
    [[ -r "$node" ]] || readable="NOT readable (input group?)"
    if ((mask & 4)); then # EV_REL — the pointer interface
      [[ -z "$ms" ]] && ms="$node ($readable)"
    elif ((mask & 1)); then # EV_KEY — the keyboard interface
      [[ -z "$kb" ]] && kb="$node ($readable)"
    fi
    board_ids="$vid:$pid"
  done
done
if [[ -n "$kb$ms" ]]; then
  echo "hw-probe evdev    board $board_ids visible: keyboard=${kb:-none} mouse=${ms:-none} — python3 tools/watch_target.py runs ON THIS machine (the target)"
else
  echo "hw-probe evdev    no USB device with the board's ids (046d:c33f, 303a:1001) here — target-side claims are 'skipped (no device)' unless the board is plugged into another machine"
fi

# Deliberate, unconditional: this script informs and must never decide anything.
exit 0