library LibNativeOrder {
    using LibSafeMathV06 for uint256;
    using LibRichErrorsV06 for bytes;

    enum OrderStatus {
        INVALID,
        FILLABLE,
        FILLED,
        CANCELLED,
        EXPIRED
    }

    /// @dev A standard OTC or OO limit order.
    struct LimitOrder {
        IERC20TokenV06 makerToken;
        IERC20TokenV06 takerToken;
        uint128 makerAmount;
        uint128 takerAmount;
        uint128 takerTokenFeeAmount;
        address maker;
        address taker;
        address sender;
        address feeRecipient;
        bytes32 pool;
        uint64 expiry;
        uint256 salt;
    }

    /// @dev An RFQ limit order.
    struct RfqOrder {
        IERC20TokenV06 makerToken;
        IERC20TokenV06 takerToken;
        uint128 makerAmount;
        uint128 takerAmount;
        address maker;
        address taker;
        address txOrigin;
        bytes32 pool;
        uint64 expiry;
        uint256 salt;
    }

    /// @dev Info on a limit or RFQ order.
    struct OrderInfo {
        bytes32 orderHash;
        OrderStatus status;
        uint128 takerTokenFilledAmount;
    }

    uint256 private constant UINT_128_MASK = (1 << 128) - 1;
    uint256 private constant UINT_64_MASK = (1 << 64) - 1;
    uint256 private constant ADDRESS_MASK = (1 << 160) - 1;

    // The type hash for limit orders, which is:
    // keccak256(abi.encodePacked(
    //     "LimitOrder(",
    //       "address makerToken,",
    //       "address takerToken,",
    //       "uint128 makerAmount,",
    //       "uint128 takerAmount,",
    //       "uint128 takerTokenFeeAmount,",
    //       "address maker,",
    //       "address taker,",
    //       "address sender,",
    //       "address feeRecipient,",
    //       "bytes32 pool,",
    //       "uint64 expiry,",
    //       "uint256 salt"
    //     ")"
    // ))
    uint256 private constant _LIMIT_ORDER_TYPEHASH =
        0xce918627cb55462ddbb85e73de69a8b322f2bc88f4507c52fcad6d4c33c29d49;

    // The type hash for RFQ orders, which is:
    // keccak256(abi.encodePacked(
    //     "RfqOrder(",
    //       "address makerToken,",
    //       "address takerToken,",
    //       "uint128 makerAmount,",
    //       "uint128 takerAmount,",
    //       "address maker,",
    //       "address taker,",
    //       "address txOrigin,",
    //       "bytes32 pool,",
    //       "uint64 expiry,",
    //       "uint256 salt"
    //     ")"
    // ))
    uint256 private constant _RFQ_ORDER_TYPEHASH =
        0xe593d3fdfa8b60e5e17a1b2204662ecbe15c23f2084b9ad5bae40359540a7da9;

    /// @dev Get the struct hash of a limit order.
    /// @param order The limit order.
    /// @return structHash The struct hash of the order.
    function getLimitOrderStructHash(LimitOrder memory order)
        internal
        pure
        returns (bytes32 structHash)
    {
        // The struct hash is:
        // keccak256(abi.encode(
        //   TYPE_HASH,
        //   order.makerToken,
        //   order.takerToken,
        //   order.makerAmount,
        //   order.takerAmount,
        //   order.takerTokenFeeAmount,
        //   order.maker,
        //   order.taker,
        //   order.sender,
        //   order.feeRecipient,
        //   order.pool,
        //   order.expiry,
        //   order.salt,
        // ))
        assembly {
            let mem := mload(0x40)
            mstore(mem, _LIMIT_ORDER_TYPEHASH)
            // order.makerToken;
            mstore(add(mem, 0x20), and(ADDRESS_MASK, mload(order)))
            // order.takerToken;
            mstore(add(mem, 0x40), and(ADDRESS_MASK, mload(add(order, 0x20))))
            // order.makerAmount;
            mstore(add(mem, 0x60), and(UINT_128_MASK, mload(add(order, 0x40))))
            // order.takerAmount;
            mstore(add(mem, 0x80), and(UINT_128_MASK, mload(add(order, 0x60))))
            // order.takerTokenFeeAmount;
            mstore(add(mem, 0xA0), and(UINT_128_MASK, mload(add(order, 0x80))))
            // order.maker;
            mstore(add(mem, 0xC0), and(ADDRESS_MASK, mload(add(order, 0xA0))))
            // order.taker;
            mstore(add(mem, 0xE0), and(ADDRESS_MASK, mload(add(order, 0xC0))))
            // order.sender;
            mstore(add(mem, 0x100), and(ADDRESS_MASK, mload(add(order, 0xE0))))
            // order.feeRecipient;
            mstore(add(mem, 0x120), and(ADDRESS_MASK, mload(add(order, 0x100))))
            // order.pool;
            mstore(add(mem, 0x140), mload(add(order, 0x120)))
            // order.expiry;
            mstore(add(mem, 0x160), and(UINT_64_MASK, mload(add(order, 0x140))))
            // order.salt;
            mstore(add(mem, 0x180), mload(add(order, 0x160)))
            structHash := keccak256(mem, 0x1A0)
        }
    }

    /// @dev Get the struct hash of a RFQ order.
    /// @param order The RFQ order.
    /// @return structHash The struct hash of the order.
    function getRfqOrderStructHash(RfqOrder memory order)
        internal
        pure
        returns (bytes32 structHash)
    {
        // The struct hash is:
        // keccak256(abi.encode(
        //   TYPE_HASH,
        //   order.makerToken,
        //   order.takerToken,
        //   order.makerAmount,
        //   order.takerAmount,
        //   order.maker,
        //   order.taker,
        //   order.txOrigin,
        //   order.pool,
        //   order.expiry,
        //   order.salt,
        // ))
        assembly {
            let mem := mload(0x40)
            mstore(mem, _RFQ_ORDER_TYPEHASH)
            // order.makerToken;
            mstore(add(mem, 0x20), and(ADDRESS_MASK, mload(order)))
            // order.takerToken;
            mstore(add(mem, 0x40), and(ADDRESS_MASK, mload(add(order, 0x20))))
            // order.makerAmount;
            mstore(add(mem, 0x60), and(UINT_128_MASK, mload(add(order, 0x40))))
            // order.takerAmount;
            mstore(add(mem, 0x80), and(UINT_128_MASK, mload(add(order, 0x60))))
            // order.maker;
            mstore(add(mem, 0xA0), and(ADDRESS_MASK, mload(add(order, 0x80))))
            // order.taker;
            mstore(add(mem, 0xC0), and(ADDRESS_MASK, mload(add(order, 0xA0))))
            // order.txOrigin;
            mstore(add(mem, 0xE0), and(ADDRESS_MASK, mload(add(order, 0xC0))))
            // order.pool;
            mstore(add(mem, 0x100), mload(add(order, 0xE0)))
            // order.expiry;
            mstore(add(mem, 0x120), and(UINT_64_MASK, mload(add(order, 0x100))))
            // order.salt;
            mstore(add(mem, 0x140), mload(add(order, 0x120)))
            structHash := keccak256(mem, 0x160)
        }
    }

    /// @dev Refund any leftover protocol fees in `msg.value` to `msg.sender`.
    /// @param ethProtocolFeePaid How much ETH was paid in protocol fees.
    function refundExcessProtocolFeeToSender(uint256 ethProtocolFeePaid)
        internal
    {
        if (msg.value > ethProtocolFeePaid && msg.sender != address(this)) {
            uint256 refundAmount = msg.value.safeSub(ethProtocolFeePaid);
            (bool success,) = msg
                .sender
                .call{value: refundAmount}("");
            if (!success) {
                LibNativeOrdersRichErrors.ProtocolFeeRefundFailed(
                    msg.sender,
                    refundAmount
                ).rrevert();
            }
        }
    }
}
/// @dev A library for common native order operations.
function getLimitOrderStructHash(LimitOrder memory order)
        internal
        pure
        returns (bytes32 structHash)
    {
        // The struct hash is:
        // keccak256(abi.encode(
        //   TYPE_HASH,
        //   order.makerToken,
        //   order.takerToken,
        //   order.makerAmount,
        //   order.takerAmount,
        //   order.takerTokenFeeAmount,
        //   order.maker,
        //   order.taker,
        //   order.sender,
        //   order.feeRecipient,
        //   order.pool,
        //   order.expiry,
        //   order.salt,
        // ))
        assembly {
            let mem := mload(0x40)
            mstore(mem, _LIMIT_ORDER_TYPEHASH)
            // order.makerToken;
            mstore(add(mem, 0x20), and(ADDRESS_MASK, mload(order)))
            // order.takerToken;
            mstore(add(mem, 0x40), and(ADDRESS_MASK, mload(add(order, 0x20))))
            // order.makerAmount;
            mstore(add(mem, 0x60), and(UINT_128_MASK, mload(add(order, 0x40))))
            // order.takerAmount;
            mstore(add(mem, 0x80), and(UINT_128_MASK, mload(add(order, 0x60))))
            // order.takerTokenFeeAmount;
            mstore(add(mem, 0xA0), and(UINT_128_MASK, mload(add(order, 0x80))))
            // order.maker;
            mstore(add(mem, 0xC0), and(ADDRESS_MASK, mload(add(order, 0xA0))))
            // order.taker;
            mstore(add(mem, 0xE0), and(ADDRESS_MASK, mload(add(order, 0xC0))))
            // order.sender;
            mstore(add(mem, 0x100), and(ADDRESS_MASK, mload(add(order, 0xE0))))
            // order.feeRecipient;
            mstore(add(mem, 0x120), and(ADDRESS_MASK, mload(add(order, 0x100))))
            // order.pool;
            mstore(add(mem, 0x140), mload(add(order, 0x120)))
            // order.expiry;
            mstore(add(mem, 0x160), and(UINT_64_MASK, mload(add(order, 0x140))))
            // order.salt;
            mstore(add(mem, 0x180), mload(add(order, 0x160)))
            structHash := keccak256(mem, 0x1A0)
        }
    }
/// @dev Get the struct hash of a limit order.
/// @param order The limit order.
/// @return structHash The struct hash of the order.