# @version 0.2.7
"""
@title USDN Burner
@notice Return 50% of USDN to pool LPs, convert remaining to 3CRV
"""

from vyper.interfaces import ERC20

interface PoolProxy:
    def withdraw_admin_fees(_pool: address): nonpayable
    def donate_admin_fees(_pool: address): nonpayable


interface RegistrySwap:
    def exchange(
        _poool: address,
        _from: address,
        _to: address,
        _amount: uint256,
        _expected: uint256,
        _receiver: address,
    ) -> uint256: payable

interface AddressProvider:
    def get_address(_id: uint256) -> address: view


ADDRESS_PROVIDER: constant(address) = 0x0000000022D53366457F9d5E68Ec105046FC4383
TRIPOOL_LP: constant(address) = 0x6c3F90f043a72FA612cbac8115EE7e52BDe6E490
USDN_POOL: constant(address) = 0x0f9cb53Ebe405d49A0bbdBD291A65Ff571bC83e1
USDN: constant(address) = 0x674C6Ad92Fd080e4004b2312b45f796a192D27a0

is_approved: HashMap[address, bool]

receiver: public(address)
recovery: public(address)
pool_proxy: public(address)

is_killed: public(bool)

owner: public(address)
emergency_owner: public(address)
future_owner: public(address)
future_emergency_owner: public(address)


@external
def __init__(_pool_proxy: address, _receiver: address, _recovery: address, _owner: address, _emergency_owner: address):
    """
    @notice Contract constructor
    @param _receiver Address that converted tokens are transferred to.
                     Should be set to an `UnderlyingBurner` deployment.
    @param _recovery Address that tokens are transferred to during an
                     emergency token recovery.
    @param _owner Owner address. Can kill the contract, recover tokens
                  and modify the recovery address.
    @param _emergency_owner Emergency owner address. Can kill the contract
                            and recover tokens.
    """
    self.pool_proxy = _pool_proxy
    self.receiver = _receiver
    self.recovery = _recovery
    self.owner = _owner
    self.emergency_owner = _emergency_owner


@payable
@external
def burn(_coin: address) -> bool:
    """
    @notice Swap `_coin` for 3CRV and transfer to the fee distributor
    @param _coin Address of the coin being swapped
    @return bool success
    """
    assert not self.is_killed  # dev: is killed
    assert _coin == USDN  # dev: only USDN

    # transfer coins from caller
    amount: uint256 = ERC20(USDN).balanceOf(msg.sender)
    if amount != 0:
        ERC20(USDN).transferFrom(msg.sender, self, amount)

    # get actual balance in case of transfer fee or pre-existing balance
    amount = ERC20(USDN).balanceOf(self)

    if amount > 1:
        # withdraw any pending fees from USDN pool
        PoolProxy(self.pool_proxy).withdraw_admin_fees(USDN_POOL)

        # transfer 50% of USDN back into the pool
        ERC20(USDN).transfer(USDN_POOL, amount / 2)

        # donate tranferred USDN to LPs
        PoolProxy(self.pool_proxy).donate_admin_fees(USDN_POOL)

        # swap remaining USDN for 3CRV and transfer to fee distributor
        amount = ERC20(USDN).balanceOf(self)
        registry_swap: address = AddressProvider(ADDRESS_PROVIDER).get_address(2)
        if not self.is_approved[registry_swap]:
            ERC20(USDN).approve(registry_swap, MAX_UINT256)
            self.is_approved[registry_swap] = True

        RegistrySwap(registry_swap).exchange(USDN_POOL, USDN, TRIPOOL_LP, amount, 0, self.receiver)

    return True


@external
def recover_balance(_coin: address) -> bool:
    """
    @notice Recover ERC20 tokens from this contract
    @dev Tokens are sent to the recovery address
    @param _coin Token address
    @return bool success
    """
    assert msg.sender in [self.owner, self.emergency_owner]  # dev: only owner

    amount: uint256 = ERC20(_coin).balanceOf(self)
    response: Bytes[32] = raw_call(
        _coin,
        concat(
            method_id("transfer(address,uint256)"),
            convert(self.recovery, bytes32),
            convert(amount, bytes32),
        ),
        max_outsize=32,
    )
    if len(response) != 0:
        assert convert(response, bool)

    return True


@external
def set_recovery(_recovery: address) -> bool:
    """
    @notice Set the token recovery address
    @param _recovery Token recovery address
    @return bool success
    """
    assert msg.sender == self.owner  # dev: only owner
    self.recovery = _recovery

    return True


@external
def set_pool_proxy(_pool_proxy: address) -> bool:
    """
    @notice Set the pool proxy address
    @param _pool_proxy Pool proxy address
    @return bool success
    """
    assert msg.sender == self.owner  # dev: only owner
    self.pool_proxy = _pool_proxy

    return True


@external
def set_killed(_is_killed: bool) -> bool:
    """
    @notice Set killed status for this contract
    @dev When killed, the `burn` function cannot be called
    @param _is_killed Killed status
    @return bool success
    """
    assert msg.sender in [self.owner, self.emergency_owner]  # dev: only owner
    self.is_killed = _is_killed

    return True



@external
def commit_transfer_ownership(_future_owner: address) -> bool:
    """
    @notice Commit a transfer of ownership
    @dev Must be accepted by the new owner via `accept_transfer_ownership`
    @param _future_owner New owner address
    @return bool success
    """
    assert msg.sender == self.owner  # dev: only owner
    self.future_owner = _future_owner

    return True


@external
def accept_transfer_ownership() -> bool:
    """
    @notice Accept a transfer of ownership
    @return bool success
    """
    assert msg.sender == self.future_owner  # dev: only owner
    self.owner = msg.sender

    return True


@external
def commit_transfer_emergency_ownership(_future_owner: address) -> bool:
    """
    @notice Commit a transfer of ownership
    @dev Must be accepted by the new owner via `accept_transfer_ownership`
    @param _future_owner New owner address
    @return bool success
    """
    assert msg.sender == self.emergency_owner  # dev: only owner
    self.future_emergency_owner = _future_owner

    return True


@external
def accept_transfer_emergency_ownership() -> bool:
    """
    @notice Accept a transfer of ownership
    @return bool success
    """
    assert msg.sender == self.future_emergency_owner  # dev: only owner
    self.emergency_owner = msg.sender

    return True

• No Contract Security Audit Submitted- Submit Audit Here

[{"outputs":[],"inputs":[{"type":"address","name":"_pool_proxy"},{"type":"address","name":"_receiver"},{"type":"address","name":"_recovery"},{"type":"address","name":"_owner"},{"type":"address","name":"_emergency_owner"}],"stateMutability":"nonpayable","type":"constructor"},{"name":"burn","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_coin"}],"stateMutability":"payable","type":"function","gas":50183},{"name":"recover_balance","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_coin"}],"stateMutability":"nonpayable","type":"function","gas":7769},{"name":"set_recovery","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_recovery"}],"stateMutability":"nonpayable","type":"function","gas":36413},{"name":"set_pool_proxy","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_pool_proxy"}],"stateMutability":"nonpayable","type":"function","gas":36443},{"name":"set_killed","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"bool","name":"_is_killed"}],"stateMutability":"nonpayable","type":"function","gas":37700},{"name":"commit_transfer_ownership","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_future_owner"}],"stateMutability":"nonpayable","type":"function","gas":36503},{"name":"accept_transfer_ownership","outputs":[{"type":"bool","name":""}],"inputs":[],"stateMutability":"nonpayable","type":"function","gas":36429},{"name":"commit_transfer_emergency_ownership","outputs":[{"type":"bool","name":""}],"inputs":[{"type":"address","name":"_future_owner"}],"stateMutability":"nonpayable","type":"function","gas":36563},{"name":"accept_transfer_emergency_ownership","outputs":[{"type":"bool","name":""}],"inputs":[],"stateMutability":"nonpayable","type":"function","gas":36489},{"name":"receiver","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1421},{"name":"recovery","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1451},{"name":"pool_proxy","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1481},{"name":"is_killed","outputs":[{"type":"bool","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1511},{"name":"owner","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1541},{"name":"emergency_owner","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1571},{"name":"future_owner","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1601},{"name":"future_emergency_owner","outputs":[{"type":"address","name":""}],"inputs":[],"stateMutability":"view","type":"function","gas":1631}]

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