#!/usr/bin/env bash
set -eu;

##
## check input
##

BUILDCTL_CONTEXT=${PLUGIN_CONTEXT:-$(pwd)}
BUILDCTL_DOCKERFILE=$(dirname "${PLUGIN_DOCKERFILE:-$BUILDCTL_CONTEXT/Dockerfile}")
if [[ ! -f $BUILDCTL_DOCKERFILE/Dockerfile ]]; then
	echo "Dockerfile $BUILDCTL_DOCKERFILE/Dockerfile not found!"
	exit 1
fi

BUILDCTL_FRONTEND=${PLUGIN_FRONTEND:-dockerfile.v0}
if [[ "$BUILDCTL_FRONTEND" != "dockerfile.v0" ]]; then
	echo "Only frontend 'dockerfile.v0' testet and supported yet."
	exit 1
fi

SOURCE_DATE_EPOCH=${PLUGIN_SOURCE_DATE_EPOCH:-0}

if [[ -n "${PLUGIN_AUTH:-}" ]]; then
	echo "$PLUGIN_AUTH" | jq -r 'to_entries|map({(.key):{"auth":(.value.username+":"+.value.password)|@base64}})|add|{"auths":.}' > "$HOME/.docker/config.json"
	echo "Stored credentials at $HOME/.docker/config.json"
	echo
fi

##
## build command
##

COMMAND="buildctl"
COMMAND="$COMMAND build"
if [[ -n "${PLUGIN_ADDR:-}" ]]; then
	COMMAND="$COMMAND --addr $PLUGIN_ADDR"
fi
COMMAND="$COMMAND --frontend $BUILDCTL_FRONTEND"
COMMAND="$COMMAND --local context='$BUILDCTL_CONTEXT'"
COMMAND="$COMMAND --local dockerfile='$BUILDCTL_DOCKERFILE'"
if [[ "${PLUGIN_PLATFORM:-}" == "true" ]]; then
	COMMAND="$COMMAND --opt platform='$PLUGIN_PLATFORM'"
fi

# https://github.com/moby/buildkit/blob/master/README.md#output
OUTPUT=""
if [[ -n "${PLUGIN_NAME:-}" ]]; then
	OUTPUT="--output type=image"
	if [[ "$1" =~ .*,.* ]]; then
		# https://github.com/moby/buildkit/issues/797#issuecomment-1561601104
		OUTPUT=",\\\"name=$PLUGIN_NAME\\\""
	else
		OUTPUT=",name=$PLUGIN_NAME"
	fi
	OUTPUT="$OUTPUT,oci-mediatypes=true,compression=estargz,compression-level=9"
	OUTPUT="$OUTPUT,rewrite-timestamp=true"
	#OUTPUT="$OUTPUT$(echo "$PLUGIN_ANNOTATION" | jq --join-output 'keys[] as $k|",annotation.\($k)=\"\(.[$k])\""')"
fi
COMMAND="$COMMAND $OUTPUT"

# custom args, e.g. docker run --rm --volume=$HOME:HOME:ro --workdir=$PWD kokuwaio/buildkit --opt buildarg=foo=bar
if [[ -n "${1:-}" ]]; then
	COMMAND="$COMMAND $*"
fi

##
## execute command
##

echo
echo Reproduce with docker:
echo
echo "SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH docker buildx build ${PLUGIN_CONTEXT:-.}"
	echo "  --no-cache"
if [[ "${PLUGIN_PLATFORM:-}" == "true" ]]; then
	echo "  --platform='$PLUGIN_PLATFORM'"
fi
if [[ -n "${OUTPUT:-}" ]]; then
	echo "  $OUTPUT"
fi
echo
echo Running now:
echo
echo -e "SOURCE_DATE_EPOCH=$SOURCE_DATE_EPOCH ${COMMAND// --/\\n  --}"
echo

eval "$COMMAND"