#!/bin/bash
# Test splitting an Arch Linux image.
set -xeuo pipefail
shopt -s inherit_errexit

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO_ROOT="$(cd "${SCRIPT_DIR}/../.." && pwd)"
# shellcheck source=SCRIPTDIR/lib.sh
. "${SCRIPT_DIR}/lib.sh"

TARGET_IMAGE="quay.io/archlinux/archlinux:latest"
CHUNKED_IMAGE="localhost/archlinux-chunked:test"

output_dir="${OUTPUT_DIR:?}"
cleanup() {
  cleanup_images "${CHUNKED_IMAGE}"
}
trap cleanup EXIT

# build split image using Containerfile.splitter API
podman pull "${TARGET_IMAGE}"
config_str=$(podman inspect "${TARGET_IMAGE}")
buildah_build \
  --from "${TARGET_IMAGE}" --build-arg CHUNKAH="${CHUNKAH_IMG:?}" \
  --build-arg CHUNKAH_CONFIG_STR="${config_str}" \
  --build-arg "CHUNKAH_ARGS=--max-layers 96 --write-manifest-to /run/output/manifest.json" \
  -v "${output_dir}:/run/output" \
  -t "${CHUNKED_IMAGE}" "${REPO_ROOT}/Containerfile.splitter"

# sanity-check it
podman run --rm "${CHUNKED_IMAGE}" cat /etc/os-release | grep "Arch Linux"

# check for expected Arch Linux components
assert_has_components "${CHUNKED_IMAGE}" "alpm/linux-api-headers" "alpm/systemd" "alpm/glibc" "alpm/pacman-mirrorlist"

# verify we got exactly 96 layers
assert_layer_count "${CHUNKED_IMAGE}" 96

# verify unclaimed component is under 10MiB (10485760 bytes)
unclaimed_size=$(jq '.components["chunkah/unclaimed"].size' "${output_dir}/manifest.json")
[[ -n "${unclaimed_size}" ]]
[[ ${unclaimed_size} -le 10485760 ]]

# verify chunked image is not larger than original + 1%
# (catches possible e.g. bad hardlink handling)
size_original=$(podman image inspect "${TARGET_IMAGE}" | jq '.[0].Size')
size_chunked=$(podman image inspect "${CHUNKED_IMAGE}" | jq '.[0].Size')
max_size=$((size_original * 101 / 100))
[[ ${size_chunked} -le ${max_size} ]]

# verify the chunked image is equivalent to the source
assert_no_diff "${TARGET_IMAGE}" "${CHUNKED_IMAGE}"