#!/bin/sh
# An unprivileged container cannot activate swap, so the run is expected to fail
# at mkswap or swapon - which of the two depends on the host's /proc/swaps.
# Everything before it - findmnt, fallocate, chmod - runs for real.
set -eu

fail() {
    echo "FAIL: $1" >&2
    exit 1
}

SWAPFORGE="$(command -v swap-forge)" || fail "swap-forge is not on PATH after install"
echo "ok: swap-forge installed at ${SWAPFORGE}"

command -v swafo >/dev/null || fail "the swafo alias is not on PATH after install"
echo "ok: swafo alias installed"

case "${SWAPFORGE}" in
    /usr/local/bin/*) ;;
    *) fail "swap-forge resolved to ${SWAPFORGE}, outside the install prefix" ;;
esac
echo "ok: resolved from the installed package, not the source tree"

for binary in findmnt swapoff chmod mkswap swapon fallocate chattr btrfs dd; do
    command -v "${binary}" >/dev/null || fail "${binary} is missing from the image"
done
echo "ok: every declared binary is present"

swap-forge --help | grep -q "Swapfile size" || fail "--help does not describe the tool"
echo "ok: --help"

set +e
swap-forge >/dev/null 2>&1
status=$?
set -e
[ "${status}" -eq 2 ] || fail "a missing size exited ${status}, expected 2"
echo "ok: a missing size exits 2"

set +e
output="$(swap-forge 64T 2>&1)"
status=$?
set -e
[ "${status}" -eq 1 ] || fail "an invalid size exited ${status}, expected 1"
echo "${output}" | grep -q "Invalid size format" || fail "invalid size message wrong"
if echo "${output}" | grep -q "Traceback"; then
    fail "an invalid size produced a traceback"
fi
echo "ok: an invalid size exits 1 without a traceback"

printf 'UUID=deadbeef / ext4 defaults 0 1\n' >/etc/fstab
cp /etc/fstab /tmp/fstab.before

set +e
output="$(swap-forge 8M 2>&1)"
status=$?
set -e
[ "${status}" -eq 1 ] || fail "the blocked activation exited ${status}, expected 1"
echo "${output}" | grep -q "Creating 8 MiB swapfile" || fail "the creation banner is missing"
echo "${output}" | grep -qE "'(mkswap|swapon)' failed with exit code" || fail "the blocked activation was not reported cleanly"
if echo "${output}" | grep -q "Traceback"; then
    fail "the blocked activation produced a traceback"
fi
echo "ok: real fallocate and chmod ran; the blocked activation exits 1 cleanly"

[ -f /swapfile ] || fail "/swapfile was not created"
size="$(stat -c %s /swapfile)"
[ "${size}" -eq 8388608 ] || fail "/swapfile is ${size} bytes, expected 8388608"
echo "ok: /swapfile exists with exactly the requested size"

cmp -s /etc/fstab /tmp/fstab.before || fail "/etc/fstab changed although activation failed"
echo "ok: /etc/fstab is untouched when activation fails"

set +e
output="$(swap-forge 8M 2>&1)"
status=$?
set -e
[ "${status}" -eq 0 ] || fail "the idempotent rerun exited ${status}, expected 0"
echo "${output}" | grep -q "already exists with correct size (8 MiB). Skipping." \
    || fail "an existing swapfile of the right size was not detected"
echo "ok: a rerun with the same size is a no-op - the idempotency the role relies on"

set +e
output="$(swap-forge 12M 2>&1)"
status=$?
set -e
echo "${output}" | grep -q "has size 8 MiB, expected 12 MiB. Recreating..." \
    || fail "a size change did not trigger a recreation"
size="$(stat -c %s /swapfile)"
[ "${size}" -eq 12582912 ] || fail "/swapfile is ${size} bytes after resize, expected 12582912"
echo "ok: a different size really removes and recreates the swapfile"

cmp -s /etc/fstab /tmp/fstab.before || fail "/etc/fstab changed during the resize cycle"
echo "ok: /etc/fstab survived the resize cycle byte for byte"

set +e
output="$(env PATH=/nonexistent-bin "${SWAPFORGE}" 8M 2>&1)"
status=$?
set -e
[ "${status}" -eq 127 ] || fail "missing findmnt exited ${status}, expected 127"
echo "${output}" | grep -q "required command 'findmnt' is not installed" || fail "missing findmnt message wrong"
echo "ok: missing findmnt exits 127 with a clean message"

echo "ALL E2E CHECKS PASSED"