#!/bin/sh
set -eu

message_file=$1

# Git-generated merge commits do not represent an independently authored
# product change and inherit provenance from their parents.
case "$(basename "$message_file")" in
  MERGE_MSG) exit 0 ;;
esac

if ! grep -Eq '^Issue: #[0-9]+[[:space:]]*$' "$message_file"; then
  echo "House Plan: missing 'Issue: #<number>' trailer (see PROCESS.md)." >&2
  exit 1
fi
if ! grep -Eq '^User-Visible: (yes|no)[[:space:]]*$' "$message_file"; then
  echo "House Plan: missing 'User-Visible: yes|no' trailer (see PROCESS.md)." >&2
  exit 1
fi

if git diff --cached --name-only --diff-filter=ACMR \
    | grep -Eq '^demo/golden/baselines/.*\.(png|json)$'; then
  if ! grep -Eq '^Release: [^[:space:]].*$' "$message_file"; then
    echo "House Plan: a golden baseline commit requires a Release trailer." >&2
    exit 1
  fi
  if ! grep -Eq '^Baseline-Reviewed: [^[:space:]].*$' "$message_file"; then
    echo "House Plan: a golden baseline commit requires Baseline-Reviewed provenance." >&2
    exit 1
  fi
fi