interface IVaultsCoreState {
  event CumulativeRateUpdated(address indexed collateralType, uint256 elapsedTime, uint256 newCumulativeRate); //cumulative interest rate from deployment time T0

  function initializeRates(address _collateralType) external;

  function refresh() external;

  function refreshCollateral(address collateralType) external;

  function syncState(IVaultsCoreState _stateAddress) external;

  function syncStateFromV1(IVaultsCoreV1 _core) external;

  //Read only
  function a() external view returns (IAddressProvider);

  function availableIncome() external view returns (uint256);

  function cumulativeRates(address _collateralType) external view returns (uint256);

  function lastRefresh(address _collateralType) external view returns (uint256);

  function synced() external view returns (bool);
}
// 
function a() external view returns (IAddressProvider);
//Read only