#!/usr/bin/env bash

# Copyright (c) 2026 Tigera, Inc. All rights reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# image-exists STAMP_FILE [EXPECTED_REF]
#
# Prints MISSING-IMAGE when the stamp's recorded image ref is absent from
# Docker or differs from EXPECTED_REF. Used as a Make prereq via $(shell), so
# either case forces the stamp's rule to re-run.

set -u

stamp=${1:?usage: image-exists STAMP_FILE [EXPECTED_REF]}
expected=${2:-}

[ -f "$stamp" ] || exit 0
img=$(cat "$stamp")
[ -n "$img" ] || exit 0
if [ -n "$expected" ] && [ "$img" != "$expected" ]; then
    echo MISSING-IMAGE
    exit 0
fi
docker image inspect "$img" >/dev/null 2>&1 && exit 0
echo MISSING-IMAGE