#!/usr/bin/env bash

set -euo pipefail

# get which branch the branch is based

current_branch=$(git name-rev --name-only HEAD)

i=0
while true; do
	i=$((i + 1))
	resolved_rev=$(git name-rev --name-only HEAD~$i)

	IFS="~" read b rest < <(echo $resolved_rev)

	if [ "$b" != "$current_branch" ]; then
		parent=$(git rev-parse HEAD~$i)
		echo parent_branch: $resolved_rev $parent >&2
		echo $parent
		exit 0
	fi
done
