#!/usr/bin/env bash
# The fast lint lanes on the uncommitted files only — ruff (check + format) on Python, eslint on the
# frontend's code and prettier on all of the frontend — for a check after every edit instead of a
# full gate run. It is a convenience, never the gate: scripts/check.sh stays what a merge or a
# release requires.
#
#   bash scripts/lint-changed.sh          lint what `git status` shows as changed or new
#   bash scripts/lint-changed.sh --hook   the same, as a Claude Code Stop hook: silent and exit 0 when
#                                         clean; otherwise the findings on stderr and exit 2, which
#                                         hands them back to the agent before it ends its turn
#
# Measured 2026-10-04: one cold eslint run (type-aware) takes 3.4–4.7 s, so this runs once per turn
# (Stop), not after every edit — a warm daemon (eslint_d) would add a dependency and a stray process.
set -u
cd "$(dirname "$0")/.." || exit 2
hook=0
[ "${1:-}" = --hook ] && hook=1

if [ "$hook" = 1 ]; then
  # A Stop hook that blocked once is told so on the next stop; let that one through, or an unfixable
  # finding would keep the agent in a loop.
  grep -q '"stop_hook_active": *true' && exit 0
fi

mapfile -t changed < <(git status --porcelain --untracked-files=all | sed -E 's/^.. //; s/.* -> //' |
  while read -r f; do [ -f "$f" ] && printf '%s\n' "$f"; done)
# eslint reads code; prettier reads every file the gate's `prettier --check .` does (a locale JSON,
# a stylesheet), and `--ignore-unknown` passes over the ones it has no parser for.
py=() fe=() pretty=()
for f in "${changed[@]}"; do
  case "$f" in
    backend/*.py | scripts/*.py) py+=("$f") ;;
  esac
  case "$f" in
    frontend/*.ts | frontend/*.tsx | frontend/*.js | frontend/*.mjs) fe+=("${f#frontend/}") ;;
  esac
  case "$f" in
    frontend/*) pretty+=("${f#frontend/}") ;;
  esac
done

report="$(
  if [ ${#py[@]} -gt 0 ]; then
    python -m ruff check --quiet --config backend/ruff.toml "${py[@]}" 2>&1
    python -m ruff format --check --quiet --config backend/ruff.toml "${py[@]}" 2>&1
  fi
  if [ ${#fe[@]} -gt 0 ]; then
    (cd frontend && npx eslint --max-warnings 0 "${fe[@]}" 2>&1)
  fi
  if [ ${#pretty[@]} -gt 0 ]; then
    (cd frontend && npx prettier --check --ignore-unknown --log-level warn "${pretty[@]}" 2>&1)
  fi
)"

if [ -z "$report" ]; then
  [ "$hook" = 1 ] || echo "lint-changed: clean (${#py[@]} py, ${#pretty[@]} frontend)"
  exit 0
fi
if [ "$hook" = 1 ]; then
  printf 'lint-changed found problems in the uncommitted files:\n%s\n' "$report" >&2
  exit 2
fi
printf '%s\n' "$report"
exit 1