/*
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        rrp pr   wr00rrp      prwww0  pp   wr pp w00r prwwwpr  0rw    prwww0  pp   wr pp   wr    r0
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         prwr wrr0wpwr        00        www0   0w0ww    www0   0w     00        www0    www0   0www0
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*/
// SPDX-License-Identifier: MIT

// File: @openzeppelin/contracts/token/ERC20/IERC20.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender) external view returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(address sender, address recipient, uint256 amount) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(address indexed owner, address indexed spender, uint256 value);
}

// File: @powerpool/poweroracle/contracts/interfaces/IPowerPoke.sol

pragma solidity ^0.6.12;
pragma experimental ABIEncoderV2;

interface IPowerPoke {
  /*** CLIENT'S CONTRACT INTERFACE ***/
  function authorizeReporter(uint256 userId_, address pokerKey_) external view;

  function authorizeNonReporter(uint256 userId_, address pokerKey_) external view;

  function authorizeNonReporterWithDeposit(
    uint256 userId_,
    address pokerKey_,
    uint256 overrideMinDeposit_
  ) external view;

  function authorizePoker(uint256 userId_, address pokerKey_) external view;

  function authorizePokerWithDeposit(
    uint256 userId_,
    address pokerKey_,
    uint256 overrideMinStake_
  ) external view;

  function slashReporter(uint256 slasherId_, uint256 times_) external;

  function reward(
    uint256 userId_,
    uint256 gasUsed_,
    uint256 compensationPlan_,
    bytes calldata pokeOptions_
  ) external;

  /*** CLIENT OWNER INTERFACE ***/
  function transferClientOwnership(address client_, address to_) external;

  function addCredit(address client_, uint256 amount_) external;

  function withdrawCredit(
    address client_,
    address to_,
    uint256 amount_
  ) external;

  function setReportIntervals(
    address client_,
    uint256 minReportInterval_,
    uint256 maxReportInterval_
  ) external;

  function setSlasherHeartbeat(address client_, uint256 slasherHeartbeat_) external;

  function setGasPriceLimit(address client_, uint256 gasPriceLimit_) external;

  function setFixedCompensations(
    address client_,
    uint256 eth_,
    uint256 cvp_
  ) external;

  function setBonusPlan(
    address client_,
    uint256 planId_,
    bool active_,
    uint64 bonusNominator_,
    uint64 bonusDenominator_,
    uint64 perGas_
  ) external;

  function setMinimalDeposit(address client_, uint256 defaultMinDeposit_) external;

  /*** POKER INTERFACE ***/
  function withdrawRewards(uint256 userId_, address to_) external;

  function setPokerKeyRewardWithdrawAllowance(uint256 userId_, bool allow_) external;

  /*** OWNER INTERFACE ***/
  function addClient(
    address client_,
    address owner_,
    bool canSlash_,
    uint256 gasPriceLimit_,
    uint256 minReportInterval_,
    uint256 maxReportInterval_
  ) external;

  function setClientActiveFlag(address client_, bool active_) external;

  function setCanSlashFlag(address client_, bool canSlash) external;

  function setOracle(address oracle_) external;

  function pause() external;

  function unpause() external;

  /*** GETTERS ***/
  function creditOf(address client_) external view returns (uint256);

  function ownerOf(address client_) external view returns (address);

  function getMinMaxReportIntervals(address client_) external view returns (uint256 min, uint256 max);

  function getSlasherHeartbeat(address client_) external view returns (uint256);

  function getGasPriceLimit(address client_) external view returns (uint256);

  function getPokerBonus(
    address client_,
    uint256 bonusPlanId_,
    uint256 gasUsed_,
    uint256 userDeposit_
  ) external view returns (uint256);

  function getGasPriceFor(address client_) external view returns (uint256);
}

// File: @openzeppelin/contracts/math/SafeMath.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @dev Wrappers over Solidity's arithmetic operations with added overflow
 * checks.
 *
 * Arithmetic operations in Solidity wrap on overflow. This can easily result
 * in bugs, because programmers usually assume that an overflow raises an
 * error, which is the standard behavior in high level programming languages.
 * `SafeMath` restores this intuition by reverting the transaction when an
 * operation overflows.
 *
 * Using this library instead of the unchecked operations eliminates an entire
 * class of bugs, so it's recommended to use it always.
 */
library SafeMath {
    /**
     * @dev Returns the addition of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `+` operator.
     *
     * Requirements:
     *
     * - Addition cannot overflow.
     */
    function add(uint256 a, uint256 b) internal pure returns (uint256) {
        uint256 c = a + b;
        require(c >= a, "SafeMath: addition overflow");

        return c;
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b) internal pure returns (uint256) {
        return sub(a, b, "SafeMath: subtraction overflow");
    }

    /**
     * @dev Returns the subtraction of two unsigned integers, reverting with custom message on
     * overflow (when the result is negative).
     *
     * Counterpart to Solidity's `-` operator.
     *
     * Requirements:
     *
     * - Subtraction cannot overflow.
     */
    function sub(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b <= a, errorMessage);
        uint256 c = a - b;

        return c;
    }

    /**
     * @dev Returns the multiplication of two unsigned integers, reverting on
     * overflow.
     *
     * Counterpart to Solidity's `*` operator.
     *
     * Requirements:
     *
     * - Multiplication cannot overflow.
     */
    function mul(uint256 a, uint256 b) internal pure returns (uint256) {
        // Gas optimization: this is cheaper than requiring 'a' not being zero, but the
        // benefit is lost if 'b' is also tested.
        // See: https://github.com/OpenZeppelin/openzeppelin-contracts/pull/522
        if (a == 0) {
            return 0;
        }

        uint256 c = a * b;
        require(c / a == b, "SafeMath: multiplication overflow");

        return c;
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b) internal pure returns (uint256) {
        return div(a, b, "SafeMath: division by zero");
    }

    /**
     * @dev Returns the integer division of two unsigned integers. Reverts with custom message on
     * division by zero. The result is rounded towards zero.
     *
     * Counterpart to Solidity's `/` operator. Note: this function uses a
     * `revert` opcode (which leaves remaining gas untouched) while Solidity
     * uses an invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function div(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b > 0, errorMessage);
        uint256 c = a / b;
        // assert(a == b * c + a % b); // There is no case in which this doesn't hold

        return c;
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b) internal pure returns (uint256) {
        return mod(a, b, "SafeMath: modulo by zero");
    }

    /**
     * @dev Returns the remainder of dividing two unsigned integers. (unsigned integer modulo),
     * Reverts with custom message when dividing by zero.
     *
     * Counterpart to Solidity's `%` operator. This function uses a `revert`
     * opcode (which leaves remaining gas untouched) while Solidity uses an
     * invalid opcode to revert (consuming all remaining gas).
     *
     * Requirements:
     *
     * - The divisor cannot be zero.
     */
    function mod(uint256 a, uint256 b, string memory errorMessage) internal pure returns (uint256) {
        require(b != 0, errorMessage);
        return a % b;
    }
}

// File: @openzeppelin/contracts/utils/Address.sol

pragma solidity >=0.6.2 <0.8.0;

/**
 * @dev Collection of functions related to the address type
 */
library Address {
    /**
     * @dev Returns true if `account` is a contract.
     *
     * [IMPORTANT]
     * ====
     * It is unsafe to assume that an address for which this function returns
     * false is an externally-owned account (EOA) and not a contract.
     *
     * Among others, `isContract` will return false for the following
     * types of addresses:
     *
     *  - an externally-owned account
     *  - a contract in construction
     *  - an address where a contract will be created
     *  - an address where a contract lived, but was destroyed
     * ====
     */
    function isContract(address account) internal view returns (bool) {
        // This method relies on extcodesize, which returns 0 for contracts in
        // construction, since the code is only stored at the end of the
        // constructor execution.

        uint256 size;
        // solhint-disable-next-line no-inline-assembly
        assembly { size := extcodesize(account) }
        return size > 0;
    }

    /**
     * @dev Replacement for Solidity's `transfer`: sends `amount` wei to
     * `recipient`, forwarding all available gas and reverting on errors.
     *
     * https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
     * of certain opcodes, possibly making contracts go over the 2300 gas limit
     * imposed by `transfer`, making them unable to receive funds via
     * `transfer`. {sendValue} removes this limitation.
     *
     * https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
     *
     * IMPORTANT: because control is transferred to `recipient`, care must be
     * taken to not create reentrancy vulnerabilities. Consider using
     * {ReentrancyGuard} or the
     * https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
     */
    function sendValue(address payable recipient, uint256 amount) internal {
        require(address(this).balance >= amount, "Address: insufficient balance");

        // solhint-disable-next-line avoid-low-level-calls, avoid-call-value
        (bool success, ) = recipient.call{ value: amount }("");
        require(success, "Address: unable to send value, recipient may have reverted");
    }

    /**
     * @dev Performs a Solidity function call using a low level `call`. A
     * plain`call` is an unsafe replacement for a function call: use this
     * function instead.
     *
     * If `target` reverts with a revert reason, it is bubbled up by this
     * function (like regular Solidity function calls).
     *
     * Returns the raw returned data. To convert to the expected return value,
     * use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
     *
     * Requirements:
     *
     * - `target` must be a contract.
     * - calling `target` with `data` must not revert.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data) internal returns (bytes memory) {
      return functionCall(target, data, "Address: low-level call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
     * `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCall(address target, bytes memory data, string memory errorMessage) internal returns (bytes memory) {
        return functionCallWithValue(target, data, 0, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but also transferring `value` wei to `target`.
     *
     * Requirements:
     *
     * - the calling contract must have an ETH balance of at least `value`.
     * - the called Solidity function must be `payable`.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value) internal returns (bytes memory) {
        return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
    }

    /**
     * @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
     * with `errorMessage` as a fallback revert reason when `target` reverts.
     *
     * _Available since v3.1._
     */
    function functionCallWithValue(address target, bytes memory data, uint256 value, string memory errorMessage) internal returns (bytes memory) {
        require(address(this).balance >= value, "Address: insufficient balance for call");
        require(isContract(target), "Address: call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.call{ value: value }(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
        return functionStaticCall(target, data, "Address: low-level static call failed");
    }

    /**
     * @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
     * but performing a static call.
     *
     * _Available since v3.3._
     */
    function functionStaticCall(address target, bytes memory data, string memory errorMessage) internal view returns (bytes memory) {
        require(isContract(target), "Address: static call to non-contract");

        // solhint-disable-next-line avoid-low-level-calls
        (bool success, bytes memory returndata) = target.staticcall(data);
        return _verifyCallResult(success, returndata, errorMessage);
    }

    function _verifyCallResult(bool success, bytes memory returndata, string memory errorMessage) private pure returns(bytes memory) {
        if (success) {
            return returndata;
        } else {
            // Look for revert reason and bubble it up if present
            if (returndata.length > 0) {
                // The easiest way to bubble the revert reason is using memory via assembly

                // solhint-disable-next-line no-inline-assembly
                assembly {
                    let returndata_size := mload(returndata)
                    revert(add(32, returndata), returndata_size)
                }
            } else {
                revert(errorMessage);
            }
        }
    }
}

// File: @openzeppelin/contracts/token/ERC20/SafeERC20.sol

pragma solidity >=0.6.0 <0.8.0;

/**
 * @title SafeERC20
 * @dev Wrappers around ERC20 operations that throw on failure (when the token
 * contract returns false). Tokens that return no value (and instead revert or
 * throw on failure) are also supported, non-reverting calls are assumed to be
 * successful.
 * To use this library you can add a `using SafeERC20 for IERC20;` statement to your contract,
 * which allows you to call the safe operations as `token.safeTransfer(...)`, etc.
 */
library SafeERC20 {
    using SafeMath for uint256;
    using Address for address;

    function safeTransfer(IERC20 token, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transfer.selector, to, value));
    }

    function safeTransferFrom(IERC20 token, address from, address to, uint256 value) internal {
        _callOptionalReturn(token, abi.encodeWithSelector(token.transferFrom.selector, from, to, value));
    }

    /**
     * @dev Deprecated. This function has issues similar to the ones found in
     * {IERC20-approve}, and its usage is discouraged.
     *
     * Whenever possible, use {safeIncreaseAllowance} and
     * {safeDecreaseAllowance} instead.
     */
    function safeApprove(IERC20 token, address spender, uint256 value) internal {
        // safeApprove should only be called when setting an initial allowance,
        // or when resetting it to zero. To increase and decrease it, use
        // 'safeIncreaseAllowance' and 'safeDecreaseAllowance'
        // solhint-disable-next-line max-line-length
        require((value == 0) || (token.allowance(address(this), spender) == 0),
            "SafeERC20: approve from non-zero to non-zero allowance"
        );
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, value));
    }

    function safeIncreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).add(value);
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    function safeDecreaseAllowance(IERC20 token, address spender, uint256 value) internal {
        uint256 newAllowance = token.allowance(address(this), spender).sub(value, "SafeERC20: decreased allowance below zero");
        _callOptionalReturn(token, abi.encodeWithSelector(token.approve.selector, spender, newAllowance));
    }

    /**
     * @dev Imitates a Solidity high-level call (i.e. a regular function call to a contract), relaxing the requirement
     * on the return value: the return value is optional (but if data is returned, it must not be false).
     * @param token The token targeted by the call.
     * @param data The call data (encoded using abi.encode or one of its variants).
     */
    function _callOptionalReturn(IERC20 token, bytes memory data) private {
        // We need to perform a low level call here, to bypass Solidity's return data size checking mechanism, since
        // we're implementing it ourselves. We use {Address.functionCall} to perform this call, which verifies that
        // the target address contains contract code and also asserts for success in the low-level call.

        bytes memory returndata = address(token).functionCall(data, "SafeERC20: low-level call failed");
        if (returndata.length > 0) { // Return data is optional
            // solhint-disable-next-line max-line-length
            require(abi.decode(returndata, (bool)), "SafeERC20: ERC20 operation did not succeed");
        }
    }
}

// File: contracts/interfaces/BMathInterface.sol

pragma solidity 0.6.12;

interface BMathInterface {
  function calcInGivenOut(
    uint256 tokenBalanceIn,
    uint256 tokenWeightIn,
    uint256 tokenBalanceOut,
    uint256 tokenWeightOut,
    uint256 tokenAmountOut,
    uint256 swapFee
  ) external pure returns (uint256 tokenAmountIn);

  function calcSingleInGivenPoolOut(
    uint256 tokenBalanceIn,
    uint256 tokenWeightIn,
    uint256 poolSupply,
    uint256 totalWeight,
    uint256 poolAmountOut,
    uint256 swapFee
  ) external pure returns (uint256 tokenAmountIn);
}

// File: contracts/interfaces/BPoolInterface.sol

pragma solidity 0.6.12;

interface BPoolInterface is IERC20, BMathInterface {
  function joinPool(uint256 poolAmountOut, uint256[] calldata maxAmountsIn) external;

  function exitPool(uint256 poolAmountIn, uint256[] calldata minAmountsOut) external;

  function swapExactAmountIn(
    address,
    uint256,
    address,
    uint256,
    uint256
  ) external returns (uint256, uint256);

  function swapExactAmountOut(
    address,
    uint256,
    address,
    uint256,
    uint256
  ) external returns (uint256, uint256);

  function joinswapExternAmountIn(
    address,
    uint256,
    uint256
  ) external returns (uint256);

  function joinswapPoolAmountOut(
    address,
    uint256,
    uint256
  ) external returns (uint256);

  function exitswapPoolAmountIn(
    address,
    uint256,
    uint256
  ) external returns (uint256);

  function exitswapExternAmountOut(
    address,
    uint256,
    uint256
  ) external returns (uint256);

  function getDenormalizedWeight(address) external view returns (uint256);

  function getBalance(address) external view returns (uint256);

  function getSwapFee() external view returns (uint256);

  function getTotalDenormalizedWeight() external view returns (uint256);

  function getCommunityFee()
    external
    view
    returns (
      uint256,
      uint256,
      uint256,
      address
    );

  function calcAmountWithCommunityFee(
    uint256,
    uint256,
    address
  ) external view returns (uint256, uint256);

  function getRestrictions() external view returns (address);

  function isPublicSwap() external view returns (bool);

  function isFinalized() external view returns (bool);

  function isBound(address t) external view returns (bool);

  function getCurrentTokens() external view returns (address[] memory tokens);

  function getFinalTokens() external view returns (address[] memory tokens);

  function setSwapFee(uint256) external;

  function setCommunityFeeAndReceiver(
    uint256,
    uint256,
    uint256,
    address
  ) external;

  function setController(address) external;

  function setPublicSwap(bool) external;

  function finalize() external;

  function bind(
    address,
    uint256,
    uint256
  ) external;

  function rebind(
    address,
    uint256,
    uint256
  ) external;

  function unbind(address) external;

  function gulp(address) external;

  function callVoting(
    address voting,
    bytes4 signature,
    bytes calldata args,
    uint256 value
  ) external;

  function getMinWeight() external view returns (uint256);

  function getMaxBoundTokens() external view returns (uint256);
}

// File: contracts/interfaces/PowerIndexPoolInterface.sol

pragma solidity 0.6.12;


interface PowerIndexPoolInterface is BPoolInterface {
  function initialize(
    string calldata name,
    string calldata symbol,
    uint256 minWeightPerSecond,
    uint256 maxWeightPerSecond
  ) external;

  function bind(
    address,
    uint256,
    uint256,
    uint256,
    uint256
  ) external;

  function setDynamicWeight(
    address token,
    uint256 targetDenorm,
    uint256 fromTimestamp,
    uint256 targetTimestamp
  ) external;

  function getDynamicWeightSettings(address token)
    external
    view
    returns (
      uint256 fromTimestamp,
      uint256 targetTimestamp,
      uint256 fromDenorm,
      uint256 targetDenorm
    );

  function getMinWeight() external view override returns (uint256);

  function getWeightPerSecondBounds() external view returns (uint256, uint256);

  function setWeightPerSecondBounds(uint256, uint256) external;

  function setWrapper(address, bool) external;

  function getWrapperMode() external view returns (bool);
}

// File: contracts/interfaces/TokenInterface.sol

pragma solidity 0.6.12;


interface TokenInterface is IERC20 {
  function deposit() external payable;

  function withdraw(uint256) external;
}

// File: contracts/interfaces/ICurveDepositor.sol

pragma solidity 0.6.12;

interface ICurveDepositor {
  function calc_withdraw_one_coin(uint256 _tokenAmount, int128 _index) external view returns (uint256);

  function remove_liquidity_one_coin(
    uint256 _token_amount,
    int128 _i,
    uint256 _min_amount
  ) external;
}

// File: contracts/interfaces/ICurveDepositor2.sol

pragma solidity 0.6.12;

interface ICurveDepositor2 {
  function add_liquidity(uint256[2] memory _amounts, uint256 _min_mint_amount) external;

  function calc_token_amount(uint256[2] memory _amounts, bool _deposit) external view returns (uint256);
}

// File: contracts/interfaces/ICurveDepositor3.sol

pragma solidity 0.6.12;

interface ICurveDepositor3 {
  function add_liquidity(uint256[3] memory _amounts, uint256 _min_mint_amount) external;

  function calc_token_amount(uint256[3] memory _amounts, bool _deposit) external view returns (uint256);
}

// File: contracts/interfaces/ICurveDepositor4.sol

pragma solidity 0.6.12;

interface ICurveDepositor4 {
  function add_liquidity(uint256[4] memory _amounts, uint256 _min_mint_amount) external;

  function calc_token_amount(uint256[4] memory _amounts, bool _deposit) external view returns (uint256);
}

// File: contracts/interfaces/IVault.sol

pragma solidity ^0.6.0;

interface IVault {
  function token() external view returns (address);

  function totalAssets() external view returns (uint256);

  function balanceOf(address _acc) external view returns (uint256);

  function pricePerShare() external view returns (uint256);

  function deposit(uint256 _amount) external;

  function withdraw(uint256 _amount) external;
}

// File: contracts/interfaces/ICurvePoolRegistry.sol

pragma solidity 0.6.12;

interface ICurvePoolRegistry {
  function get_virtual_price_from_lp_token(address _token) external view returns (uint256);
}

// File: contracts/interfaces/IErc20PiptSwap.sol

pragma solidity 0.6.12;

interface IErc20PiptSwap {
  function swapEthToPipt(uint256 _slippage) external payable returns (uint256 poolAmountOutAfterFee, uint256 oddEth);

  function swapErc20ToPipt(
    address _swapToken,
    uint256 _swapAmount,
    uint256 _slippage
  ) external payable returns (uint256 poolAmountOut);

  function defaultSlippage() external view returns (uint256);

  function swapPiptToEth(uint256 _poolAmountIn) external payable returns (uint256 ethOutAmount);

  function swapPiptToErc20(address _swapToken, uint256 _poolAmountIn) external payable returns (uint256 erc20Out);
}

// File: contracts/interfaces/IErc20VaultPoolSwap.sol

pragma solidity 0.6.12;

interface IErc20VaultPoolSwap {
  function swapErc20ToVaultPool(
    address _pool,
    address _swapToken,
    uint256 _swapAmount
  ) external returns (uint256 poolAmountOut);

  function swapVaultPoolToErc20(
    address _pool,
    uint256 _poolAmountIn,
    address _swapToken
  ) external returns (uint256 erc20Out);
}

// File: @openzeppelin/contracts-ethereum-package/contracts/Initializable.sol

pragma solidity >=0.4.24 <0.7.0;


/**
 * @title Initializable
 *
 * @dev Helper contract to support initializer functions. To use it, replace
 * the constructor with a function that has the `initializer` modifier.
 * WARNING: Unlike constructors, initializer functions must be manually
 * invoked. This applies both to deploying an Initializable contract, as well
 * as extending an Initializable contract via inheritance.
 * WARNING: When used with inheritance, manual care must be taken to not invoke
 * a parent initializer twice, or ensure that all initializers are idempotent,
 * because this is not dealt with automatically as with constructors.
 */
contract Initializable {

  /**
   * @dev Indicates that the contract has been initialized.
   */
  bool private initialized;

  /**
   * @dev Indicates that the contract is in the process of being initialized.
   */
  bool private initializing;

  /**
   * @dev Modifier to use in the initializer function of a contract.
   */
  modifier initializer() {
    require(initializing || isConstructor() || !initialized, "Contract instance has already been initialized");

    bool isTopLevelCall = !initializing;
    if (isTopLevelCall) {
      initializing = true;
      initialized = true;
    }

    _;

    if (isTopLevelCall) {
      initializing = false;
    }
  }

  /// @dev Returns true if and only if the function is running in the constructor
  function isConstructor() private view returns (bool) {
    // extcodesize checks the size of the code stored in an address, and
    // address returns the current address. Since the code is still not
    // deployed when running a constructor, any checks on its code size will
    // yield zero, making it an effective way to detect if a contract is
    // under construction or not.
    address self = address(this);
    uint256 cs;
    assembly { cs := extcodesize(self) }
    return cs == 0;
  }

  // Reserved storage space to allow for layout changes in the future.
  uint256[50] private ______gap;
}

// File: @openzeppelin/contracts-ethereum-package/contracts/GSN/Context.sol

pragma solidity ^0.6.0;


/*
 * @dev Provides information about the current execution context, including the
 * sender of the transaction and its data. While these are generally available
 * via msg.sender and msg.data, they should not be accessed in such a direct
 * manner, since when dealing with GSN meta-transactions the account sending and
 * paying for execution may not be the actual sender (as far as an application
 * is concerned).
 *
 * This contract is only required for intermediate, library-like contracts.
 */
contract ContextUpgradeSafe is Initializable {
    // Empty internal constructor, to prevent people from mistakenly deploying
    // an instance of this contract, which should be used via inheritance.

    function __Context_init() internal initializer {
        __Context_init_unchained();
    }

    function __Context_init_unchained() internal initializer {


    }


    function _msgSender() internal view virtual returns (address payable) {
        return msg.sender;
    }

    function _msgData() internal view virtual returns (bytes memory) {
        this; // silence state mutability warning without generating bytecode - see https://github.com/ethereum/solidity/issues/2691
        return msg.data;
    }

    uint256[50] private __gap;
}

// File: @openzeppelin/contracts-ethereum-package/contracts/access/Ownable.sol

pragma solidity ^0.6.0;


/**
 * @dev Contract module which provides a basic access control mechanism, where
 * there is an account (an owner) that can be granted exclusive access to
 * specific functions.
 *
 * By default, the owner account will be the one that deploys the contract. This
 * can later be changed with {transferOwnership}.
 *
 * This module is used through inheritance. It will make available the modifier
 * `onlyOwner`, which can be applied to your functions to restrict their use to
 * the owner.
 */
contract OwnableUpgradeSafe is Initializable, ContextUpgradeSafe {
    address private _owner;

    event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);

    /**
     * @dev Initializes the contract setting the deployer as the initial owner.
     */

    function __Ownable_init() internal initializer {
        __Context_init_unchained();
        __Ownable_init_unchained();
    }

    function __Ownable_init_unchained() internal initializer {


        address msgSender = _msgSender();
        _owner = msgSender;
        emit OwnershipTransferred(address(0), msgSender);

    }


    /**
     * @dev Returns the address of the current owner.
     */
    function owner() public view returns (address) {
        return _owner;
    }

    /**
     * @dev Throws if called by any account other than the owner.
     */
    modifier onlyOwner() {
        require(_owner == _msgSender(), "Ownable: caller is not the owner");
        _;
    }

    /**
     * @dev Leaves the contract without owner. It will not be possible to call
     * `onlyOwner` functions anymore. Can only be called by the current owner.
     *
     * NOTE: Renouncing ownership will leave the contract without an owner,
     * thereby removing any functionality that is only available to the owner.
     */
    function renounceOwnership() public virtual onlyOwner {
        emit OwnershipTransferred(_owner, address(0));
        _owner = address(0);
    }

    /**
     * @dev Transfers ownership of the contract to a new account (`newOwner`).
     * Can only be called by the current owner.
     */
    function transferOwnership(address newOwner) public virtual onlyOwner {
        require(newOwner != address(0), "Ownable: new owner is the zero address");
        emit OwnershipTransferred(_owner, newOwner);
        _owner = newOwner;
    }

    uint256[49] private __gap;
}

// File: contracts/traits/ProgressiveFee.sol

pragma solidity 0.6.12;

contract ProgressiveFee is OwnableUpgradeSafe {
  using SafeMath for uint256;

  uint256[] public feeLevels;
  uint256[] public feeAmounts;
  address public feePayout;
  address public feeManager;

  event SetFees(
    address indexed sender,
    uint256[] newFeeLevels,
    uint256[] newFeeAmounts,
    address indexed feePayout,
    address indexed feeManager
  );

  modifier onlyFeeManagerOrOwner() {
    require(msg.sender == feeManager || msg.sender == owner(), "NOT_FEE_MANAGER");
    _;
  }

  function setFees(
    uint256[] calldata _feeLevels,
    uint256[] calldata _feeAmounts,
    address _feePayout,
    address _feeManager
  ) external onlyFeeManagerOrOwner {
    feeLevels = _feeLevels;
    feeAmounts = _feeAmounts;
    feePayout = _feePayout;
    feeManager = _feeManager;

    emit SetFees(msg.sender, _feeLevels, _feeAmounts, _feePayout, _feeManager);
  }

  function calcFee(uint256 amount, uint256 wrapperFee) public view returns (uint256 feeAmount, uint256 amountAfterFee) {
    uint256 len = feeLevels.length;
    for (uint256 i = 0; i < len; i++) {
      if (amount >= feeLevels[i]) {
        feeAmount = amount.mul(feeAmounts[i]).div(1 ether);
        break;
      }
    }
    feeAmount = feeAmount.add(wrapperFee);
    amountAfterFee = amount.sub(feeAmount);
  }

  function getFeeLevels() external view returns (uint256[] memory) {
    return feeLevels;
  }

  function getFeeAmounts() external view returns (uint256[] memory) {
    return feeAmounts;
  }
}

// File: contracts/Erc20VaultPoolSwap.sol

pragma solidity 0.6.12;

contract Erc20VaultPoolSwap is ProgressiveFee, IErc20VaultPoolSwap {
  using SafeERC20 for IERC20;

  event TakeFee(address indexed pool, address indexed token, uint256 amount);

  event SetVaultConfig(
    address indexed token,
    address depositor,
    uint256 depositorAmountLength,
    uint256 depositorIndex,
    address lpToken,
    address indexed vaultRegistry
  );

  event Erc20ToVaultPoolSwap(address indexed user, address indexed pool, uint256 usdcInAmount, uint256 poolOutAmount);
  event VaultPoolToErc20Swap(address indexed user, address indexed pool, uint256 poolInAmount, uint256 usdcOutAmount);
  event ClaimFee(address indexed token, address indexed payout, uint256 amount);

  IERC20 public immutable usdc;

  mapping(address => address[]) public poolTokens;

  struct VaultConfig {
    uint256 depositorLength;
    uint256 depositorIndex;
    address depositor;
    address lpToken;
    address vaultRegistry;
  }
  mapping(address => VaultConfig) public vaultConfig;

  struct VaultCalc {
    address token;
    uint256 tokenBalance;
    uint256 input;
    uint256 correctInput;
    uint256 poolAmountOut;
  }

  constructor(address _usdc) public {
    __Ownable_init();
    usdc = IERC20(_usdc);
  }

  function setVaultConfigs(
    address[] memory _tokens,
    address[] memory _depositors,
    uint256[] memory _depositorAmountLength,
    uint256[] memory _depositorIndexes,
    address[] memory _lpTokens,
    address[] memory _vaultRegistries
  ) external onlyOwner {
    uint256 len = _tokens.length;
    require(
      len == _depositors.length &&
        len == _depositorAmountLength.length &&
        len == _depositorIndexes.length &&
        len == _lpTokens.length &&
        len == _vaultRegistries.length,
      "L"
    );
    for (uint256 i = 0; i < len; i++) {
      vaultConfig[_tokens[i]] = VaultConfig(
        _depositorAmountLength[i],
        _depositorIndexes[i],
        _depositors[i],
        _lpTokens[i],
        _vaultRegistries[i]
      );

      usdc.approve(_depositors[i], uint256(-1));
      IERC20(_lpTokens[i]).approve(_tokens[i], uint256(-1));
      IERC20(_lpTokens[i]).approve(_depositors[i], uint256(-1));
      emit SetVaultConfig(
        _tokens[i],
        _depositors[i],
        _depositorAmountLength[i],
        _depositorIndexes[i],
        _lpTokens[i],
        _vaultRegistries[i]
      );
    }
  }

  function updatePools(address[] memory _pools) external onlyOwner {
    uint256 len = _pools.length;
    for (uint256 i = 0; i < len; i++) {
      _updatePool(_pools[i]);
    }
  }

  function claimFee(address[] memory _tokens) external onlyOwner {
    require(feePayout != address(0), "FP_NOT_SET");

    uint256 len = _tokens.length;
    for (uint256 i = 0; i < len; i++) {
      uint256 amount = IERC20(_tokens[i]).balanceOf(address(this));
      IERC20(_tokens[i]).safeTransfer(feePayout, amount);
      emit ClaimFee(_tokens[i], feePayout, amount);
    }
  }

  function swapErc20ToVaultPool(
    address _pool,
    address _swapToken,
    uint256 _swapAmount
  ) external override returns (uint256 poolAmountOut) {
    require(_swapToken == address(usdc), "ONLY_USDC");
    usdc.safeTransferFrom(msg.sender, address(this), _swapAmount);

    (, uint256 _swapAmountWithFee) = calcFee(_swapAmount, 0);

    uint256[] memory tokensInPipt;
    (poolAmountOut, tokensInPipt) = _depositVaultAndGetTokensInPipt(_pool, _swapAmountWithFee);

    PowerIndexPoolInterface(_pool).joinPool(poolAmountOut, tokensInPipt);
    (, uint256 communityFee, , ) = PowerIndexPoolInterface(_pool).getCommunityFee();
    poolAmountOut = poolAmountOut.sub(poolAmountOut.mul(communityFee).div(1 ether)) - 1;

    IERC20(_pool).safeTransfer(msg.sender, poolAmountOut);

    emit Erc20ToVaultPoolSwap(msg.sender, _pool, _swapAmount, poolAmountOut);
  }

  function swapVaultPoolToErc20(
    address _pool,
    uint256 _poolAmountIn,
    address _swapToken
  ) external override returns (uint256 erc20Out) {
    require(_swapToken == address(usdc), "ONLY_USDC");
    IERC20(_pool).safeTransferFrom(msg.sender, address(this), _poolAmountIn);

    (, uint256 _poolAmountInWithFee) = calcFee(_poolAmountIn, 0);

    erc20Out = _redeemVault(_pool, _poolAmountInWithFee);

    usdc.safeTransfer(msg.sender, erc20Out);

    emit VaultPoolToErc20Swap(msg.sender, _pool, _poolAmountIn, erc20Out);
  }

  /* ==========  View Functions  ========== */

  function calcVaultOutByUsdc(address _token, uint256 _usdcIn) public view returns (uint256 amountOut) {
    VaultConfig storage vc = vaultConfig[_token];
    uint256 lpByUsdcPrice = ICurvePoolRegistry(vc.vaultRegistry).get_virtual_price_from_lp_token(vc.lpToken);
    uint256 vaultByLpPrice = IVault(_token).pricePerShare();
    return _usdcIn.mul(1e30).div(vaultByLpPrice.mul(lpByUsdcPrice).div(1 ether));
  }

  function calcVaultPoolOutByUsdc(
    address _pool,
    uint256 _usdcIn,
    bool _withFee
  ) external view returns (uint256 amountOut) {
    uint256 len = poolTokens[_pool].length;
    PowerIndexPoolInterface p = PowerIndexPoolInterface(_pool);
    uint256 piptTotalSupply = p.totalSupply();

    (VaultCalc[] memory vc, uint256 restInput, uint256 totalCorrectInput) =
      getVaultCalcsForSupply(_pool, piptTotalSupply, _usdcIn);

    uint256[] memory tokensInPipt = new uint256[](len);
    for (uint256 i = 0; i < len; i++) {
      uint256 share = vc[i].correctInput.mul(1 ether).div(totalCorrectInput);
      vc[i].correctInput = vc[i].correctInput.add(restInput.mul(share).div(1 ether)).sub(100);

      tokensInPipt[i] = calcVaultOutByUsdc(vc[i].token, vc[i].correctInput);

      uint256 poolOutByToken = tokensInPipt[i].sub(1e12).mul(piptTotalSupply).div(vc[i].tokenBalance);
      if (poolOutByToken < amountOut || amountOut == 0) {
        amountOut = poolOutByToken;
      }
    }
    if (_withFee) {
      (, uint256 communityJoinFee, , ) = p.getCommunityFee();
      (amountOut, ) = p.calcAmountWithCommunityFee(amountOut, communityJoinFee, address(this));
    }
  }

  function calcUsdcOutByVault(address _token, uint256 _vaultIn) public view returns (uint256 amountOut) {
    VaultConfig storage vc = vaultConfig[_token];
    uint256 lpByUsdcPrice = ICurvePoolRegistry(vc.vaultRegistry).get_virtual_price_from_lp_token(vc.lpToken);
    uint256 vaultByLpPrice = IVault(_token).pricePerShare();
    return _vaultIn.mul(vaultByLpPrice.mul(lpByUsdcPrice).div(1 ether)).div(1e30);
  }

  function calcUsdcOutByPool(
    address _pool,
    uint256 _ppolIn,
    bool _withFee
  ) external view returns (uint256 amountOut) {
    uint256 len = poolTokens[_pool].length;
    PowerIndexPoolInterface p = PowerIndexPoolInterface(_pool);

    if (_withFee) {
      (, , uint256 communityExitFee, ) = p.getCommunityFee();
      (_ppolIn, ) = p.calcAmountWithCommunityFee(_ppolIn, communityExitFee, address(this));
    }

    uint256 ratio = _ppolIn.mul(1 ether).div(p.totalSupply());

    for (uint256 i = 0; i < len; i++) {
      address t = poolTokens[_pool][i];
      uint256 bal = p.getBalance(t);
      amountOut = amountOut.add(calcUsdcOutByVault(t, ratio.mul(bal).div(1 ether)));
    }
  }

  function getVaultCalcsForSupply(
    address _pool,
    uint256 piptTotalSupply,
    uint256 totalInputAmount
  )
    public
    view
    returns (
      VaultCalc[] memory vc,
      uint256 restInput,
      uint256 totalCorrectInput
    )
  {
    uint256 len = poolTokens[_pool].length;
    vc = new VaultCalc[](len);

    uint256 minPoolAmount;
    for (uint256 i = 0; i < len; i++) {
      vc[i].token = poolTokens[_pool][i];
      vc[i].tokenBalance = PowerIndexPoolInterface(_pool).getBalance(vc[i].token);
      vc[i].input = totalInputAmount / len;
      vc[i].poolAmountOut = calcVaultOutByUsdc(vc[i].token, vc[i].input).mul(piptTotalSupply).div(vc[i].tokenBalance);
      if (minPoolAmount == 0 || vc[i].poolAmountOut < minPoolAmount) {
        minPoolAmount = vc[i].poolAmountOut;
      }
    }

    for (uint256 i = 0; i < len; i++) {
      if (vc[i].poolAmountOut > minPoolAmount) {
        uint256 ratio = minPoolAmount.mul(1 ether).div(vc[i].poolAmountOut);
        vc[i].correctInput = ratio.mul(vc[i].input).div(1 ether);
        restInput = restInput.add(vc[i].input.sub(vc[i].correctInput));
      } else {
        vc[i].correctInput = vc[i].input;
      }
    }

    totalCorrectInput = totalInputAmount.sub(restInput).sub(100);
  }

  /* ==========  Internal Functions  ========== */

  function _depositVaultAndGetTokensInPipt(address _pool, uint256 _totalInputAmount)
    internal
    returns (uint256 poolAmountOut, uint256[] memory tokensInPipt)
  {
    require(_totalInputAmount != 0, "NULL_INPUT");
    uint256 len = poolTokens[_pool].length;
    uint256 piptTotalSupply = PowerIndexPoolInterface(_pool).totalSupply();

    (VaultCalc[] memory vc, uint256 restInput, uint256 totalCorrectInput) =
      getVaultCalcsForSupply(_pool, piptTotalSupply, _totalInputAmount);

    tokensInPipt = new uint256[](len);
    for (uint256 i = 0; i < len; i++) {
      uint256 share = vc[i].correctInput.mul(1 ether).div(totalCorrectInput);
      vc[i].correctInput = vc[i].correctInput.add(restInput.mul(share).div(1 ether)).sub(100);

      uint256 balanceBefore = IVault(vc[i].token).balanceOf(address(this));
      IVault(vc[i].token).deposit(_addYearnLpTokenLiquidity(vaultConfig[vc[i].token], vc[i].correctInput));
      tokensInPipt[i] = IVault(vc[i].token).balanceOf(address(this)).sub(balanceBefore);

      uint256 poolOutByToken = tokensInPipt[i].sub(1e12).mul(piptTotalSupply).div(vc[i].tokenBalance);
      if (poolOutByToken < poolAmountOut || poolAmountOut == 0) {
        poolAmountOut = poolOutByToken;
      }
    }
    require(poolAmountOut != 0, "NULL_OUTPUT");
  }

  function _addYearnLpTokenLiquidity(VaultConfig storage vc, uint256 _amount) internal returns (uint256) {
    uint256 balanceBefore = IERC20(vc.lpToken).balanceOf(address(this));
    if (vc.depositorLength == 2) {
      uint256[2] memory amounts;
      amounts[vc.depositorIndex] = _amount;
      ICurveDepositor2(vc.depositor).add_liquidity(amounts, 1);
    }

    if (vc.depositorLength == 3) {
      uint256[3] memory amounts;
      amounts[vc.depositorIndex] = _amount;
      ICurveDepositor3(vc.depositor).add_liquidity(amounts, 1);
    }

    if (vc.depositorLength == 4) {
      uint256[4] memory amounts;
      amounts[vc.depositorIndex] = _amount;
      ICurveDepositor4(vc.depositor).add_liquidity(amounts, 1);
    }
    uint256 balanceAfter = IERC20(vc.lpToken).balanceOf(address(this));
    return balanceAfter.sub(balanceBefore);
  }

  function _redeemVault(address _pool, uint256 _totalInputAmount) internal returns (uint256 totalOutputAmount) {
    require(_totalInputAmount != 0, "NULL_INPUT");
    address[] memory tokens = poolTokens[_pool];
    uint256 len = tokens.length;

    uint256[] memory amounts = new uint256[](len);
    for (uint256 i = 0; i < len; i++) {
      amounts[i] = IERC20(tokens[i]).balanceOf(address(this));
    }
    PowerIndexPoolInterface(_pool).exitPool(_totalInputAmount, amounts);
    for (uint256 i = 0; i < len; i++) {
      amounts[i] = IERC20(tokens[i]).balanceOf(address(this)).sub(amounts[i]);
    }

    uint256 outputTokenBalanceBefore = usdc.balanceOf(address(this));
    for (uint256 i = 0; i < len; i++) {
      VaultConfig storage vc = vaultConfig[tokens[i]];
      uint256 lpTokenBalanceBefore = IERC20(vc.lpToken).balanceOf(address(this));
      IVault(tokens[i]).withdraw(amounts[i]);
      ICurveDepositor(vc.depositor).remove_liquidity_one_coin(
        IERC20(vc.lpToken).balanceOf(address(this)).sub(lpTokenBalanceBefore),
        int128(vc.depositorIndex),
        1
      );
    }
    totalOutputAmount = usdc.balanceOf(address(this)).sub(outputTokenBalanceBefore);
    require(totalOutputAmount != 0, "NULL_OUTPUT");
  }

  function _updatePool(address _pool) internal {
    poolTokens[_pool] = PowerIndexPoolInterface(_pool).getCurrentTokens();
    uint256 len = poolTokens[_pool].length;
    for (uint256 i = 0; i < len; i++) {
      IERC20(poolTokens[_pool][i]).approve(_pool, uint256(-1));
    }
  }
}