CREATE TABLE IF NOT EXISTS message_outbox (
  id TEXT PRIMARY KEY,
  channel TEXT NOT NULL,
  recipient_user_id TEXT NOT NULL,
  recipient_role TEXT,
  message_type TEXT NOT NULL,
  priority TEXT NOT NULL DEFAULT 'normal',
  title TEXT,
  content TEXT NOT NULL,
  payload TEXT,
  status TEXT NOT NULL DEFAULT 'queued',
  retry_count INTEGER NOT NULL DEFAULT 0,
  last_error TEXT,
  created_at TEXT NOT NULL,
  sent_at TEXT
);

CREATE INDEX IF NOT EXISTS idx_message_outbox_dispatch
ON message_outbox(channel, status, priority, created_at);

CREATE TABLE IF NOT EXISTS channel_bindings (
  id TEXT PRIMARY KEY,
  user_id TEXT NOT NULL,
  channel_type TEXT NOT NULL,
  external_chat_id TEXT NOT NULL,
  status TEXT NOT NULL DEFAULT 'active',
  updated_at TEXT NOT NULL
);

CREATE INDEX IF NOT EXISTS idx_channel_bindings_lookup
ON channel_bindings(user_id, channel_type, status, updated_at);

CREATE TABLE IF NOT EXISTS audit_logs (
  id TEXT PRIMARY KEY,
  actor TEXT NOT NULL,
  action TEXT NOT NULL,
  target TEXT,
  detail TEXT,
  created_at TEXT NOT NULL
);