#!/usr/bin/env bash

set -e

name="$(basename $0)"

: ${TOP_DIR:="$( cd "$( dirname "${BASH_SOURCE[0]}" )/.." && pwd )"}

source ${TOP_DIR}/docker/builder-include

: ${DOCKER_FILE:="${TOP_DIR}/docker/Dockerfile.builder"}
: ${DOCKER_FROM:="$(docker_from)"}

usage () {
	echo "${name} - Builds a docker image that contains tools for building petitboot." >&2
	echo "Usage: ${name} [flags]" >&2
	echo "Option flags:" >&2
	echo "  -d --dry-run  - Do not run build commands." >&2
	echo "  -h --help     - Show this help and exit." >&2
	echo "  -p --purge    - Remove existing docker image and rebuild." >&2
	echo "  -r --rebuild  - Rebuild existing docker image." >&2
	echo "  -t --tag      - Print Docker tag to stdout and exit." >&2
	echo "  -v --verbose  - Verbose execution." >&2
	echo "Environment:" >&2
	echo "  DOCKER_FILE   - Default: '${DOCKER_FILE}'" >&2
	echo "  DOCKER_FROM   - Default: '${DOCKER_FROM}'" >&2
	echo "  DOCKER_TAG    - Default: '${DOCKER_TAG}'" >&2
	echo "Examples:" >&2
	echo "  ${name} -v"
}

short_opts="dhprtv"
long_opts="dry-run,help,purge,rebuild,tag,verbose"

opts=$(getopt --options ${short_opts} --long ${long_opts} -n "${name}" -- "$@")

if [ $? != 0 ]; then
	echo "${name}: ERROR: Internal getopt" >&2 
	exit 1
fi

eval set -- "${opts}"

while true ; do
	case "${1}" in
	-d | --dry-run)
		dry_run=1
		shift
		;;
	-h | --help)
		usage=1
		shift
		;;
	-p | --purge)
		purge=1
		shift
		;;
	-r | --rebuild)
		rebuild=1
		shift
		;;
	-t | --tag)
		tag=1
		shift
		;;
	-v | --verbose)
		set -x
		verbose=1
		shift
		;;
	--)
		shift
		break
		;;
	*)
		echo "${name}: ERROR: Internal opts" >&2 
		exit 1
		;;
	esac
done

if [[ -n "${usage}" ]]; then
	usage
	exit 0
fi

if [[ -n "${tag}" ]]; then
	show_tag
	exit 0
fi

version () {
	echo "$@" | awk -F. '{ printf("%d%03d%03d%03d\n", $1,$2,$3,$4); }'
}

# Support for docker versions older than 17.05.
# See https://github.com/moby/moby/issues/32457
if [[ $(version "$(docker version --format '{{.Server.Version}}')") < $(version "17.05") ]]; then
	tmp_file="${DOCKER_FILE}.tmp"
	trap "rm -f ${tmp_file}" EXIT

	cp -f ${DOCKER_FILE} ${tmp_file}
	DOCKER_FILE=${tmp_file}
	sed --in-place "s|ARG DOCKER_FROM||" ${tmp_file}
	sed --in-place "s|\${DOCKER_FROM}|${DOCKER_FROM}|" ${tmp_file}
fi

if [[ -n "${purge}" ]] && docker inspect --type image ${DOCKER_TAG} >/dev/null 2>/dev/null; then
	echo "Removing docker image: ${DOCKER_TAG}" >&2
	run_cmd "docker rmi --force ${DOCKER_TAG}"
elif [[ -z "${rebuild}" ]] && docker inspect --type image ${DOCKER_TAG} >/dev/null 2>/dev/null; then
	echo "Docker image exists: ${DOCKER_TAG}" >&2
	show_tag
	exit 0
fi

echo "Building docker image: ${DOCKER_TAG}" >&2

cd ${TOP_DIR}
run_cmd "docker build \
	--file "${DOCKER_FILE}" \
	--build-arg DOCKER_FROM=${DOCKER_FROM} \
	--build-arg http_proxy=${http_proxy} \
	--build-arg https_proxy=${https_proxy} \
	--tag ${DOCKER_TAG} \
	--network=host \
	."

show_tag