#!/bin/sh

# Creates a changelog from the git commits.

FILE=""
LIST=false
TAG="0.?.?"

while [ "$1" != "" ]; do
	case $1 in
		-l | --list )
			LIST=true
			;;
		-t | --tag )
			TAG=$2
			shift
			;;
		* )
			FILE=$1
			;;
	esac
	shift
done

DATE=`date +'%Y-%m-%d'`
HEAD="\n### $DATE v$TAG\n\n"

if $LIST; then
	version=$(git describe --tags --abbrev=0 $(git rev-list --tags --max-count=1))
	if test -z "$version"; then
		git log --pretty="format:* %s"
	else
		git log --pretty="format:* %s" $version..
	fi
	exit
fi

CHANGELOG=$FILE
if test "$CHANGELOG" = ""; then
	CHANGELOG=`ls | egrep 'change|history' -i`
	if test "$CHANGELOG" = ""; then
		CHANGELOG='History.md';
	fi
fi

tmp="/tmp/changelog"
printf "$HEAD" > $tmp
git-changelog --list >> $tmp
printf '\n' >> $tmp
if [ -f $CHANGELOG ]; then cat $CHANGELOG >> $tmp; fi
mv $tmp $CHANGELOG

$EDITOR $CHANGELOG