#!/bin/sh

refname="$1"
oldrev="$2"
newrev="$3"

if [ "$refname" != "refs/heads/main" ]; then
	echo "Only refs/heads/main allowed"
	exit 1
fi

zero=$(git hash-object --stdin </dev/null | tr '[0-9a-f]' '0')
if [ "$newrev" = "$zero" ]; then
	echo "Don't delete main branch"
	exit 1
fi

exit 0