#!/bin/sh
export LANG=C

file="$1"
tab="$(printf '\t')"

history="$(git log \
	--follow \
	--ignore-all-space --diff-filter=AM \
	--date=unix --pretty=format:"%cd$tab%an" \
	-- "$file")"

dates="$(echo "$history" | cut -d"$tab" -f1)"
authors="$(echo "$history" | cut -d"$tab" -f2 | sort -u)"

cat << EOF
date: '@$(echo "$dates" | head -n1)'
date_initial: '@$(echo "$dates" | tail -n1)'
edits: $(echo "$dates" | wc -l)
authors:
$(echo "$authors" | sed 's/^/- /')
EOF