CREATE TABLE IF NOT EXISTS chat_rooms (
  id         UUID        PRIMARY KEY DEFAULT gen_random_uuid(),
  hotel_id   UUID        NOT NULL REFERENCES hotels(id) ON DELETE CASCADE,
  type       VARCHAR(10) NOT NULL DEFAULT 'general' CHECK (type IN ('general', 'direct')),
  name       VARCHAR(100),
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS chat_room_members (
  room_id UUID NOT NULL REFERENCES chat_rooms(id) ON DELETE CASCADE,
  user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  PRIMARY KEY (room_id, user_id)
);

CREATE TABLE IF NOT EXISTS chat_messages (
  id         UUID        PRIMARY KEY DEFAULT gen_random_uuid(),
  room_id    UUID        NOT NULL REFERENCES chat_rooms(id) ON DELETE CASCADE,
  hotel_id   UUID        NOT NULL REFERENCES hotels(id) ON DELETE CASCADE,
  sender_id  UUID        NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  text       TEXT        NOT NULL,
  created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);
CREATE INDEX IF NOT EXISTS idx_chat_messages_room ON chat_messages(room_id, created_at DESC);

CREATE TABLE IF NOT EXISTS chat_read_status (
  room_id    UUID        NOT NULL REFERENCES chat_rooms(id) ON DELETE CASCADE,
  user_id    UUID        NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  last_read  TIMESTAMPTZ NOT NULL DEFAULT NOW(),
  PRIMARY KEY (room_id, user_id)
);