#!/usr/bin/env bash
# Tier 3 — when the agent tries to stop, check whether feature.manifest.ts
# changes have matching test changes. If manifest moved without tests,
# nudge the agent to continue (exit 2 forces continuation).

set -euo pipefail

input=$(cat)

# Loop guard — Claude Code sets stop_hook_active when a Stop hook already
# forced continuation; don't loop infinitely.
already_stopped=$(printf '%s' "$input" | jq -r '.stop_hook_active // false')
if [ "$already_stopped" = "true" ]; then
  exit 0
fi

# Only run inside the repo
if ! git rev-parse --git-dir >/dev/null 2>&1; then
  exit 0
fi

manifest_changed=$(git diff --name-only HEAD 2>/dev/null | grep -E 'feature\.manifest\.ts$' || true)

if [ -z "$manifest_changed" ]; then
  exit 0
fi

tests_changed=$(git diff --name-only HEAD 2>/dev/null | grep -E '\.test\.(ts|tsx)$' || true)

if [ -n "$tests_changed" ]; then
  exit 0
fi

cat >&2 <<EOF
[stop-check] Manifest changes detected without matching test changes:

${manifest_changed}

Manifest-first ordering says: contracts + a red test must land before
implementation. If you already shipped tests in a previous commit on this
branch (and only the manifest changed this turn), say so and re-stop —
this hook tracks unstaged + uncommitted-on-HEAD diffs only and can't tell.

Otherwise, write the sibling test file(s) for any new use case before stopping.
EOF

exit 2