-- Migration 002 — Add missing updated_at columns and auto-update trigger
-- ─────────────────────────────────────────────────────────────────────────────
-- Tables audit:
--   hotels             ✅ created_at  ✅ updated_at
--   users              ✅ created_at  ✅ updated_at
--   rooms              ✅ created_at  ❌ updated_at  ← add
--   bookings           ✅ created_at  ✅ updated_at
--   housekeeping_tasks ✅ created_at  ❌ updated_at  ← add
--   channels           ❌ created_at  ❌ updated_at  ← add both
-- ─────────────────────────────────────────────────────────────────────────────

-- ── 1. Add missing columns ──────────────────────────────────────────────────

ALTER TABLE rooms
  ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW();

ALTER TABLE housekeeping_tasks
  ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW();

ALTER TABLE channels
  ADD COLUMN IF NOT EXISTS created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  ADD COLUMN IF NOT EXISTS updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW();

-- ── 2. Trigger function: auto-set updated_at = NOW() on every UPDATE ────────

CREATE OR REPLACE FUNCTION set_updated_at()
RETURNS TRIGGER AS $$
BEGIN
  NEW.updated_at = NOW();
  RETURN NEW;
END;
$$ LANGUAGE plpgsql;

-- ── 3. Attach trigger to every table that has updated_at ────────────────────
--    Using DROP IF EXISTS + CREATE so the migration is idempotent.

DROP TRIGGER IF EXISTS trg_hotels_updated_at             ON hotels;
DROP TRIGGER IF EXISTS trg_users_updated_at              ON users;
DROP TRIGGER IF EXISTS trg_rooms_updated_at              ON rooms;
DROP TRIGGER IF EXISTS trg_bookings_updated_at           ON bookings;
DROP TRIGGER IF EXISTS trg_housekeeping_tasks_updated_at ON housekeeping_tasks;
DROP TRIGGER IF EXISTS trg_channels_updated_at           ON channels;

CREATE TRIGGER trg_hotels_updated_at
  BEFORE UPDATE ON hotels
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TRIGGER trg_users_updated_at
  BEFORE UPDATE ON users
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TRIGGER trg_rooms_updated_at
  BEFORE UPDATE ON rooms
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TRIGGER trg_bookings_updated_at
  BEFORE UPDATE ON bookings
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TRIGGER trg_housekeeping_tasks_updated_at
  BEFORE UPDATE ON housekeeping_tasks
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

CREATE TRIGGER trg_channels_updated_at
  BEFORE UPDATE ON channels
  FOR EACH ROW EXECUTE FUNCTION set_updated_at();

-- ── 4. Indexes on created_at for archiving / range queries ──────────────────
--    Нужны чтобы запрос "дай все записи старше 6 месяцев" работал быстро.

CREATE INDEX IF NOT EXISTS idx_bookings_created_at           ON bookings(hotel_id, created_at);
CREATE INDEX IF NOT EXISTS idx_bookings_updated_at           ON bookings(hotel_id, updated_at);
CREATE INDEX IF NOT EXISTS idx_housekeeping_tasks_created_at ON housekeeping_tasks(hotel_id, created_at);
CREATE INDEX IF NOT EXISTS idx_rooms_updated_at              ON rooms(hotel_id, updated_at);
CREATE INDEX IF NOT EXISTS idx_channels_updated_at           ON channels(hotel_id, updated_at);