CREATE TABLE IF NOT EXISTS admin_users (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  username TEXT NOT NULL UNIQUE,
  password_hash TEXT NOT NULL,
  display_name TEXT NOT NULL,
  status TEXT NOT NULL DEFAULT 'active' CHECK (status IN ('active', 'disabled')),
  failed_login_count INTEGER NOT NULL DEFAULT 0,
  locked_until TEXT,
  last_login_at TEXT,
  created_at TEXT NOT NULL,
  updated_at TEXT NOT NULL
);

CREATE TABLE IF NOT EXISTS site_documents (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  document_key TEXT NOT NULL UNIQUE,
  draft_json TEXT NOT NULL,
  published_json TEXT NOT NULL,
  updated_by INTEGER,
  updated_at TEXT NOT NULL,
  published_at TEXT,
  FOREIGN KEY (updated_by) REFERENCES admin_users(id)
);

CREATE TABLE IF NOT EXISTS revisions (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  entity_type TEXT NOT NULL,
  entity_key TEXT NOT NULL,
  version INTEGER NOT NULL,
  snapshot_json TEXT NOT NULL,
  operator_id INTEGER,
  action TEXT NOT NULL,
  comment TEXT,
  created_at TEXT NOT NULL,
  FOREIGN KEY (operator_id) REFERENCES admin_users(id),
  UNIQUE(entity_type, entity_key, version)
);

CREATE TABLE IF NOT EXISTS audit_logs (
  id INTEGER PRIMARY KEY AUTOINCREMENT,
  operator_id INTEGER,
  action TEXT NOT NULL,
  entity_type TEXT NOT NULL,
  entity_key TEXT,
  ip_address TEXT,
  metadata_json TEXT NOT NULL DEFAULT '{}',
  created_at TEXT NOT NULL,
  FOREIGN KEY (operator_id) REFERENCES admin_users(id)
);

CREATE INDEX IF NOT EXISTS idx_revisions_entity ON revisions(entity_type, entity_key, version DESC);
CREATE INDEX IF NOT EXISTS idx_audit_created_at ON audit_logs(created_at DESC);