// SPDX-License-Identifier: GPL-3.0

pragma solidity 0.8.6;

import "../external/compound/ICompLike.sol";
import "../interfaces/ITicket.sol";

interface IPrizePool {
    /// @dev Event emitted when controlled token is added
    event ControlledTokenAdded(ITicket indexed token);

    event AwardCaptured(uint256 amount);

    /// @dev Event emitted when assets are deposited
    event Deposited(
        address indexed operator,
        address indexed to,
        ITicket indexed token,
        uint256 amount
    );

    /// @dev Event emitted when interest is awarded to a winner
    event Awarded(address indexed winner, ITicket indexed token, uint256 amount);

    /// @dev Event emitted when external ERC20s are awarded to a winner
    event AwardedExternalERC20(address indexed winner, address indexed token, uint256 amount);

    /// @dev Event emitted when external ERC20s are transferred out
    event TransferredExternalERC20(address indexed to, address indexed token, uint256 amount);

    /// @dev Event emitted when external ERC721s are awarded to a winner
    event AwardedExternalERC721(address indexed winner, address indexed token, uint256[] tokenIds);

    /// @dev Event emitted when assets are withdrawn
    event Withdrawal(
        address indexed operator,
        address indexed from,
        ITicket indexed token,
        uint256 amount,
        uint256 redeemed
    );

    /// @dev Event emitted when the Balance Cap is set
    event BalanceCapSet(uint256 balanceCap);

    /// @dev Event emitted when the Liquidity Cap is set
    event LiquidityCapSet(uint256 liquidityCap);

    /// @dev Event emitted when the Prize Strategy is set
    event PrizeStrategySet(address indexed prizeStrategy);

    /// @dev Event emitted when the Ticket is set
    event TicketSet(ITicket indexed ticket);

    /// @dev Emitted when there was an error thrown awarding an External ERC721
    event ErrorAwardingExternalERC721(bytes error);

    /// @notice Deposit assets into the Prize Pool in exchange for tokens
    /// @param to The address receiving the newly minted tokens
    /// @param amount The amount of assets to deposit
    function depositTo(address to, uint256 amount) external;

    /// @notice Deposit assets into the Prize Pool in exchange for tokens,
    /// then sets the delegate on behalf of the caller.
    /// @param to The address receiving the newly minted tokens
    /// @param amount The amount of assets to deposit
    /// @param delegate The address to delegate to for the caller
    function depositToAndDelegate(address to, uint256 amount, address delegate) external;

    /// @notice Withdraw assets from the Prize Pool instantly.
    /// @param from The address to redeem tokens from.
    /// @param amount The amount of tokens to redeem for assets.
    /// @return The actual amount withdrawn
    function withdrawFrom(address from, uint256 amount) external returns (uint256);

    /// @notice Called by the prize strategy to award prizes.
    /// @dev The amount awarded must be less than the awardBalance()
    /// @param to The address of the winner that receives the award
    /// @param amount The amount of assets to be awarded
    function award(address to, uint256 amount) external;

    /// @notice Returns the balance that is available to award.
    /// @dev captureAwardBalance() should be called first
    /// @return The total amount of assets to be awarded for the current prize
    function awardBalance() external view returns (uint256);

    /// @notice Captures any available interest as award balance.
    /// @dev This function also captures the reserve fees.
    /// @return The total amount of assets to be awarded for the current prize
    function captureAwardBalance() external returns (uint256);

    /// @dev Checks with the Prize Pool if a specific token type may be awarded as an external prize
    /// @param externalToken The address of the token to check
    /// @return True if the token may be awarded, false otherwise
    function canAwardExternal(address externalToken) external view returns (bool);

    // @dev Returns the total underlying balance of all assets. This includes both principal and interest.
    /// @return The underlying balance of assets
    function balance() external returns (uint256);

    /**
     * @notice Read internal Ticket accounted balance.
     * @return uint256 accountBalance
     */
    function getAccountedBalance() external view returns (uint256);

    /**
     * @notice Read internal balanceCap variable
     */
    function getBalanceCap() external view returns (uint256);

    /**
     * @notice Read internal liquidityCap variable
     */
    function getLiquidityCap() external view returns (uint256);

    /**
     * @notice Read ticket variable
     */
    function getTicket() external view returns (ITicket);

    /**
     * @notice Read token variable
     */
    function getToken() external view returns (address);

    /**
     * @notice Read prizeStrategy variable
     */
    function getPrizeStrategy() external view returns (address);

    /// @dev Checks if a specific token is controlled by the Prize Pool
    /// @param controlledToken The address of the token to check
    /// @return True if the token is a controlled token, false otherwise
    function isControlled(ITicket controlledToken) external view returns (bool);

    /// @notice Called by the Prize-Strategy to transfer out external ERC20 tokens
    /// @dev Used to transfer out tokens held by the Prize Pool.  Could be liquidated, or anything.
    /// @param to The address of the winner that receives the award
    /// @param externalToken The address of the external asset token being awarded
    /// @param amount The amount of external assets to be awarded
    function transferExternalERC20(
        address to,
        address externalToken,
        uint256 amount
    ) external;

    /// @notice Called by the Prize-Strategy to award external ERC20 prizes
    /// @dev Used to award any arbitrary tokens held by the Prize Pool
    /// @param to The address of the winner that receives the award
    /// @param amount The amount of external assets to be awarded
    /// @param externalToken The address of the external asset token being awarded
    function awardExternalERC20(
        address to,
        address externalToken,
        uint256 amount
    ) external;

    /// @notice Called by the prize strategy to award external ERC721 prizes
    /// @dev Used to award any arbitrary NFTs held by the Prize Pool
    /// @param to The address of the winner that receives the award
    /// @param externalToken The address of the external NFT token being awarded
    /// @param tokenIds An array of NFT Token IDs to be transferred
    function awardExternalERC721(
        address to,
        address externalToken,
        uint256[] calldata tokenIds
    ) external;

    /// @notice Allows the owner to set a balance cap per `token` for the pool.
    /// @dev If a user wins, his balance can go over the cap. He will be able to withdraw the excess but not deposit.
    /// @dev Needs to be called after deploying a prize pool to be able to deposit into it.
    /// @param balanceCap New balance cap.
    /// @return True if new balance cap has been successfully set.
    function setBalanceCap(uint256 balanceCap) external returns (bool);

    /// @notice Allows the Governor to set a cap on the amount of liquidity that he pool can hold
    /// @param liquidityCap The new liquidity cap for the prize pool
    function setLiquidityCap(uint256 liquidityCap) external;

    /// @notice Sets the prize strategy of the prize pool.  Only callable by the owner.
    /// @param _prizeStrategy The new prize strategy.
    function setPrizeStrategy(address _prizeStrategy) external;

    /// @notice Set prize pool ticket.
    /// @param ticket Address of the ticket to set.
    /// @return True if ticket has been successfully set.
    function setTicket(ITicket ticket) external returns (bool);

    /// @notice Delegate the votes for a Compound COMP-like token held by the prize pool
    /// @param compLike The COMP-like token held by the prize pool that should be delegated
    /// @param to The address to delegate to
    function compLikeDelegate(ICompLike compLike, address to) external;
}