#!/usr/bin/env bash
set -euo pipefail

repo_root=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
tmp_dir=$(mktemp -d)
trap 'rm -rf "${tmp_dir}"' EXIT

hugo_version="${HUGO_VERSION:?HUGO_VERSION must be set}"
upstream_template="${tmp_dir}/rss.xml"
diff_output="${tmp_dir}/rss.diff"

curl -fsSL "https://raw.githubusercontent.com/gohugoio/hugo/refs/tags/v${hugo_version}/tpl/tplimpl/embedded/templates/rss.xml" \
	-o "${upstream_template}"

set +e
diff "${upstream_template}" "${repo_root}/themes/v2/layouts/_default/rss.xml" >"${diff_output}"
diff_status=$?
set -e

if [[ "${diff_status}" -gt 1 ]]; then
	exit "${diff_status}"
fi

line_count=$(wc -l <"${diff_output}" | tr -d ' ')
if [[ "${line_count}" != "7" ]]; then
	echo "Unexpected RSS template diff line count: ${line_count}" >&2
	cat "${diff_output}" >&2
	exit 1
fi