#!/usr/bin/env bash
#
# scripts/smoke.sh — end-to-end smoke suite for banger.
#
# Drives a real create → start → ssh → exec → delete cycle against
# real Firecracker + real KVM on the host. Intended as a pre-release
# gate: the Go unit + integration tests don't and can't cover the
# post-machine.Start path (socket ownership, guest boot, vsock agent
# wait, guest SSH, workspace prepare). If this suite fails, don't
# ship.
#
# State lives under $BANGER_SMOKE_XDG_DIR (set by `make smoke`,
# defaults to build/smoke/xdg). It's ISOLATED from the invoking
# user's real banger install via XDG_{CONFIG,STATE,CACHE,RUNTIME}
# overrides, but PERSISTED across runs — so the first smoke pulls
# the golden image, subsequent smokes reuse it. `make smoke-clean`
# wipes it.
#
# Invoked via `make smoke`, which sets the three env vars below.
# Don't run this directly unless you know they're set.

set -euo pipefail

log() { printf '[smoke] %s\n' "$*" >&2; }
die() { printf '[smoke] FAIL: %s\n' "$*" >&2; exit 1; }

: "${BANGER_SMOKE_BIN_DIR:?must point at the instrumented binary dir, set by make smoke}"
: "${BANGER_SMOKE_COVER_DIR:?must point at the coverage dir, set by make smoke}"
: "${BANGER_SMOKE_XDG_DIR:?must point at the isolated XDG root, set by make smoke}"

BANGER="$BANGER_SMOKE_BIN_DIR/banger"
BANGERD="$BANGER_SMOKE_BIN_DIR/bangerd"
VSOCK_AGENT="$BANGER_SMOKE_BIN_DIR/banger-vsock-agent"

for bin in "$BANGER" "$BANGERD" "$VSOCK_AGENT"; do
  [[ -x "$bin" ]] || die "binary missing or not executable: $bin"
done

# Persistent XDG dirs (state, cache, config) so repeated smoke
# runs reuse the pulled golden image instead of re-downloading
# ~300MB each time. Runtime dir needs to be fresh per-run because
# it holds sockets the daemon cleans up on stop and refuses to
# reuse if any are stale.
mkdir -p \
  "$BANGER_SMOKE_XDG_DIR/config" \
  "$BANGER_SMOKE_XDG_DIR/state" \
  "$BANGER_SMOKE_XDG_DIR/cache"
runtime_dir="$(mktemp -d -t banger-smoke-runtime-XXXXXX)"
# shellcheck disable=SC2064
trap "rm -rf '$runtime_dir'" EXIT
chmod 0700 "$runtime_dir"

export XDG_CONFIG_HOME="$BANGER_SMOKE_XDG_DIR/config"
export XDG_STATE_HOME="$BANGER_SMOKE_XDG_DIR/state"
export XDG_CACHE_HOME="$BANGER_SMOKE_XDG_DIR/cache"
export XDG_RUNTIME_DIR="$runtime_dir"

# Point banger at its companion binaries inside the smoke build.
export BANGER_DAEMON_BIN="$BANGERD"
export BANGER_VSOCK_AGENT_BIN="$VSOCK_AGENT"

# Instrumented binaries dump coverage here on clean exit.
export GOCOVERDIR="$BANGER_SMOKE_COVER_DIR"
mkdir -p "$GOCOVERDIR"

# Any smoke daemon left behind from a prior run that crashed mid-
# scenario would reuse the stale socket path and confuse
# ensureDaemon. Best-effort stop; ignore if nothing is running.
"$BANGER" daemon stop >/dev/null 2>&1 || true

# banger's vmDNS binds 127.0.0.1:42069 (UDP) hard. If the user's
# real (non-smoke) daemon is running, its listener holds the port
# and the smoke daemon's Open() fails before any scenario runs.
# Fail fast with an actionable message — don't guess whether to
# stop the user's daemon for them.
if command -v ss >/dev/null 2>&1 && ss -Huln 2>/dev/null | awk '{print $4}' | grep -q '[:.]42069$'; then
  die 'port 127.0.0.1:42069 is already bound (likely your real banger daemon); stop it with `banger daemon stop` and re-run `make smoke`'
fi

# --- doctor -----------------------------------------------------------
log 'doctor: checking host readiness'
if ! "$BANGER" doctor; then
  die 'doctor reported failures; fix the host before running smoke'
fi

# --- bare vm run ------------------------------------------------------
log "bare vm run: create + start + ssh + exec 'echo smoke-bare-ok' + --rm"
bare_out="$("$BANGER" vm run --rm -- echo smoke-bare-ok)" || die "bare vm run exit $?"
grep -q 'smoke-bare-ok' <<<"$bare_out" || die "bare vm run stdout missing marker: $bare_out"

# --- workspace vm run -------------------------------------------------
log 'workspace vm run: preparing a throwaway git repo'
repodir="$runtime_dir/fake-repo"
mkdir -p "$repodir"
(
  cd "$repodir"
  git init -q -b main
  git config commit.gpgsign false
  git config user.name smoke
  git config user.email smoke@smoke
  echo 'smoke-workspace-marker' > smoke-file.txt
  git add .
  git commit -q -m init
)

log "workspace vm run: create + start + workspace prepare + cat guest file + --rm"
ws_out="$("$BANGER" vm run --rm "$repodir" -- cat /root/repo/smoke-file.txt)" || die "workspace vm run exit $?"
grep -q 'smoke-workspace-marker' <<<"$ws_out" || die "workspace vm run didn't ship smoke-file.txt: $ws_out"

# --- daemon stop (flushes coverage) -----------------------------------
log 'stopping daemon so instrumented binaries flush coverage'
"$BANGER" daemon stop >/dev/null 2>&1 || true
# Give the daemon a moment to write its covdata pod before the trap
# tears down runtime_dir.
sleep 0.5

log 'all scenarios passed'