#!/bin/sh

die() {
	ec=$1
	shift
	echo "$@" >&2
	exit "$ec"
}

usage() {
	die 1 "Usage: got-archive [-afsV] [-o outdir] [-t tmpdir] repo [ref...]"
}

args=$(getopt afo:st:V $*)
[ $? -ne 0 ] && usage

set -- $args

strip=0
force=0
outdir=.
tmpdir="/tmp/got-archive"

while [ $# -ne 0 ]; do
	case "$1" in
	-a)
		all=1
		shift
		;;
	-f)
		force=1
		shift
		;;
	-o)
		outdir=$2
		shift
		shift
		;;
	-s)
		strip=1
		shift
		;;
	-t)
		tmpdir=$2
		shift
		shift
		;;
	-V)
		echo "got-archive-@VERSION@"
		exit 1
		;;
	--)
		shift
		break
		;;
	esac
done

[ $# -lt 1 ] && usage

repo=$1
name=$(basename "$repo" .git)
mkdir -p "$tmpdir"
shift
[ -d "$repo" ] || die 2 "Error: invalid repo: $repo"

# $1 - ref
# $2 - name
gen() {
	cdir="$tmpdir/$2"
	tarfile="$outdir/$2.tgz"

	[ -e "$tarfile" ] && [ "$force" = 0 ] && return

	rm -rf "$cdir"
	got checkout -q -c "$1" "$repo" "$cdir" || die 3 "Error: $2: failed to checkout: $2"
	rm -rf "$cdir/.got"
	tar -czf "$tarfile" -C "$tmpdir" "$2" || die 4 "Error: $2: failed to create tarball: $tarfile"
	rm -rf "$cdir"
}

if [ "$all" = 1 ]; then
	[ $# -ne 0 ] && die 1 "Error: Can't combine -a and explicit refs" 

	tags=$(find "$repo/refs/tags" -type f -exec basename {} \; 2>/dev/null)
	[ $? -ne 0 ] && exit 0
	set -- $tags
fi

mkdir -p "$outdir"

if [ $# -gt 0 ]; then
	while [ $# -ne 0 ]; do
		if [ "$strip" = 1 ]; then
			ref=$(echo "$1" | sed 's/^v//g')
		else
			ref=$1
		fi
		gen "$1" "$name-$ref"
		shift
	done
else
	gen "HEAD" "$name"
fi