changelog

#!/usr/bin/env bash

# Sane defaults.
set -euo pipefail

# Find scripts directory.
script="$0"
if test -L "$script"; then
	script="$(readlink -f "$0")"
fi
prefix="$(dirname "$script")"
script="$(basename "$script")"

# Print the manual.
help() {
	cat <<-EOF >&2
		About
		        Generate CHANGELOG.md for given release tag.

		Usage
		        $script -h
		        $script [-x] <tag>

		Flags
		        -h      Print this manual.
		        -x      Enable debug mode.
	EOF
}

# Parse and apply flags.
while getopts ":xh" option; do
	case "$option" in
		x)
			set -x
			;;
		h)
			help
			exit
			;;
		?)
			echo "$script: unknown flag '$OPTARG', try -h" >&2
			exit
			;;
	esac
done

# Drop flags by shifting arguments.
shift $((OPTIND - 1))

# Test required arguments.
if test -z "$*"; then
	echo "$script: missing required argument, see -h" >&2
	exit
fi

# Release tag, e.g. Add-on/42.
tag="$1"

# Add-on absolute path, e.g. /Add-on.
target="$("$prefix/parse-tag" -a "$tag")"

# Tag prefix, e.g. Add-on.
prefix="${tag%/*}"

# Get the range between previous and latest release tag.
refspec="$(git describe --abbrev=0 --match "$prefix/*" -- "$tag^" 2>/dev/null || :)..$tag"

# Distributable directory, e.g. ./dist.
dist="$target/dist"

# Make sure distributable directory exists.
mkdir -p "$dist"

# List all commits between previous and latest release tag that touches the add-on directory and have issue references.
git log --format="- %h %s" "${refspec#..}" -- "$target" | grep "#[0-9]\+" > "$dist/CHANGELOG.md"