#!/usr/bin/env bash
set -euo pipefail

if [ "$#" -ne 3 ]; then
  echo "usage: build_zero_image.sh CONTEXT_DIR OUTPUT_TAR IMAGE_TAG" >&2
  exit 2
fi

context_dir=$1
output_tar=$2
image_tag=$3

mkdir -p "$(dirname "$output_tar")"
rm -f "$output_tar"

if docker buildx version >/dev/null 2>&1; then
  docker buildx build \
    --platform linux/arm64 \
    --tag "$image_tag" \
    --load \
    "$context_dir"
else
  docker build --platform linux/arm64 --tag "$image_tag" "$context_dir"
fi

docker run --rm --platform linux/arm64 "$image_tag" /usr/bin/vamp-zero --build-info
docker save "$image_tag" --output "$output_tar"