#!/bin/sh
#
# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
#
# This file is part of dobuild.
# Copyright (c) 2019 Contributors as noted in the AUTHORS file.
#
# SPDX-License-Identifier: MPL-2.0

exec 0<&-

set -e

export LANG=C
export LC_ALL=C

TOPDIR="$1"

[ -z "$TOPDIR" ] || cd "$TOPDIR"

try_git() {
  [ -d .git ] || return 1
  git show -s --format=format:%ct HEAD
}

try_svn() {
  [ -d .svn ] || return 1
  LAST_CHANGED_DATE="$(svn info | sed -n -e 's/^Last Changed Date: //p')"
  [ -n "$LAST_CHANGED_DATE" ] || return 2
  SOURCE_DATE_EPOCH="$(date -d "$LAST_CHANGED_DATE" +%s)"
}

try_mtime() {
  stat -c '%Y' "$PWD"
}

SOURCE_DATE_EPOCH="$(try_git || try_svn || try_mtime)"
echo "$SOURCE_DATE_EPOCH"