// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

/// @notice The IVRFSubscriptionV2Plus interface defines the subscription
/// @notice related methods implemented by the V2Plus coordinator.
interface IVRFSubscriptionV2Plus {
  /**
   * @notice Add a consumer to a VRF subscription.
   * @param subId - ID of the subscription
   * @param consumer - New consumer which can use the subscription
   */
  function addConsumer(uint256 subId, address consumer) external;

  /**
   * @notice Remove a consumer from a VRF subscription.
   * @param subId - ID of the subscription
   * @param consumer - Consumer to remove from the subscription
   */
  function removeConsumer(uint256 subId, address consumer) external;

  /**
   * @notice Cancel a subscription
   * @param subId - ID of the subscription
   * @param to - Where to send the remaining LINK to
   */
  function cancelSubscription(uint256 subId, address to) external;

  /**
   * @notice Accept subscription owner transfer.
   * @param subId - ID of the subscription
   * @dev will revert if original owner of subId has
   * not requested that msg.sender become the new owner.
   */
  function acceptSubscriptionOwnerTransfer(
    uint256 subId
  ) external;

  /**
   * @notice Request subscription owner transfer.
   * @param subId - ID of the subscription
   * @param newOwner - proposed new owner of the subscription
   */
  function requestSubscriptionOwnerTransfer(uint256 subId, address newOwner) external;

  /**
   * @notice Create a VRF subscription.
   * @return subId - A unique subscription id.
   * @dev You can manage the consumer set dynamically with addConsumer/removeConsumer.
   * @dev Note to fund the subscription with LINK, use transferAndCall. For example
   * @dev  LINKTOKEN.transferAndCall(
   * @dev    address(COORDINATOR),
   * @dev    amount,
   * @dev    abi.encode(subId));
   * @dev Note to fund the subscription with Native, use fundSubscriptionWithNative. Be sure
   * @dev  to send Native with the call, for example:
   * @dev COORDINATOR.fundSubscriptionWithNative{value: amount}(subId);
   */
  function createSubscription() external returns (uint256 subId);

  /**
   * @notice Get a VRF subscription.
   * @param subId - ID of the subscription
   * @return balance - LINK balance of the subscription in juels.
   * @return nativeBalance - native balance of the subscription in wei.
   * @return reqCount - Requests count of subscription.
   * @return owner - owner of the subscription.
   * @return consumers - list of consumer address which are able to use this subscription.
   */
  function getSubscription(
    uint256 subId
  )
    external
    view
    returns (uint96 balance, uint96 nativeBalance, uint64 reqCount, address owner, address[] memory consumers);

  /*
   * @notice Check to see if there exists a request commitment consumers
   * for all consumers and keyhashes for a given sub.
   * @param subId - ID of the subscription
   * @return true if there exists at least one unfulfilled request for the subscription, false
   * otherwise.
   */
  function pendingRequestExists(
    uint256 subId
  ) external view returns (bool);

  /**
   * @notice Paginate through all active VRF subscriptions.
   * @param startIndex index of the subscription to start from
   * @param maxCount maximum number of subscriptions to return, 0 to return all
   * @dev the order of IDs in the list is **not guaranteed**, therefore, if making successive calls, one
   * @dev should consider keeping the blockheight constant to ensure a holistic picture of the contract state
   */
  function getActiveSubscriptionIds(uint256 startIndex, uint256 maxCount) external view returns (uint256[] memory);

  /**
   * @notice Fund a subscription with native.
   * @param subId - ID of the subscription
   * @notice This method expects msg.value to be greater than or equal to 0.
   */
  function fundSubscriptionWithNative(
    uint256 subId
  ) external payable;
}