#!/usr/bin/env sh
# Regenerate CHANGELOG.md from Conventional Commits using git-cliff (D20).
# Install once:  pip install git-cliff   (ships prebuilt binaries)
# Usage:         packaging/changelog.sh [--tag vX.Y.Z]
set -eu

ROOT=$(CDPATH= cd -- "$(dirname -- "$0")/.." && pwd)
cd "$ROOT"

command -v git-cliff >/dev/null 2>&1 || {
    echo "git-cliff not found. Install it: pip install git-cliff"
    exit 1
}

if [ "${1:-}" = "--tag" ] && [ -n "${2:-}" ]; then
    git-cliff --tag "$2" -o CHANGELOG.md
else
    git-cliff -o CHANGELOG.md
fi
echo "Wrote CHANGELOG.md"