#!/bin/sh
set -o errexit
set -o nounset

if [ "$#" != '1' ]
then
	cat 1>&2 <<EOF
Usage: $0 VERSION

Downloads the requested version and creates a filtered source tarball.
EOF
	exit 1
fi

VERSION="${1}"
OUTDIR="${PWD}"
TMPDIR="$(mktemp -d)"
trap "rm -rf '${TMPDIR}'" INT TERM EXIT

cd "${TMPDIR}"
URL="$(rpm -E "%{pypi_source chardet ${VERSION}}")"
echo "--> Downloading: ${URL}" 1>&2
curl -L -O "${URL}"

ARCHIVE="$(find . -mindepth 1 -maxdepth 1 -type f -name '*.tar.gz' -print -quit)"
echo "--> Extracting: $(basename "${ARCHIVE}")" 1>&2
tar -xzf "${ARCHIVE}"
echo '--> Removing tests due to licensing issues' 1>&2
TARDIR="$(basename "${ARCHIVE}" '.tar.gz')"
MTIME="$(stat -c '%Y' "${TARDIR}")"
rm -rvf "${TARDIR}/tests/"
# Restore the original mtime even though we modified the base directory by
# removing the tests.
touch -d @"${MTIME}" "${TARDIR}"
FILTERED="$(basename "${ARCHIVE}" .tar.gz)-filtered.tar.zst"
echo "--> Re-archiving: ${FILTERED}" 1>&2
# https://www.gnu.org/software/tar/manual/html_section/Reproducibility.html
TZ=UTC LC_ALL=C tar \
    --create --verbose \
    --sort=name \
    --format=posix \
    --numeric-owner --owner=0 --group=0 \
    --mode=go+u,go-w \
    --pax-option='delete=atime,delete=ctime' \
    "${TARDIR}/" |
  zstdmt --ultra -22 > "${FILTERED}"
mv -v "${FILTERED}" "${OUTDIR}"
echo 'Done.' 1>&2