// File: contracts/BinaryOptionMarketFactory.sol



pragma solidity ^0.5.16;

// Inheritance
import "synthetix-2.43.1/contracts/MinimalProxyFactory.sol";
import "synthetix-2.43.1/contracts/Owned.sol";

// Internal references
import "./BinaryOptionMarket.sol";
import "synthetix-2.43.1/contracts/interfaces/IAddressResolver.sol";

contract BinaryOptionMarketFactory is MinimalProxyFactory, Owned {
    /* ========== STATE VARIABLES ========== */
    address public binaryOptionMarketManager;
    address public binaryOptionMarketMastercopy;
    address public binaryOptionMastercopy;

    /* ========== CONSTRUCTOR ========== */

    constructor(address _owner) public MinimalProxyFactory() Owned(_owner) {}

    /* ========== MUTATIVE FUNCTIONS ========== */

    function createMarket(
        address creator,
        IAddressResolver _resolver,
        bytes32 oracleKey,
        uint strikePrice,
        uint[2] calldata times, // [maturity, expiry]
        uint initialMint,
        uint[2] calldata fees // [poolFee, creatorFee]
    ) external returns (BinaryOptionMarket) {
        require(binaryOptionMarketManager == msg.sender, "Only permitted by the manager.");

        BinaryOptionMarket bom =
            BinaryOptionMarket(
                _cloneAsMinimalProxy(binaryOptionMarketMastercopy, "Could not create a Binary Option Market")
            );
        bom.initialize(
            binaryOptionMarketManager,
            binaryOptionMastercopy,
            _resolver,
            creator,
            oracleKey,
            strikePrice,
            times,
            initialMint,
            fees
        );
        return bom;
    }

    /* ========== SETTERS ========== */
    function setBinaryOptionMarketManager(address _binaryOptionMarketManager) external onlyOwner {
        binaryOptionMarketManager = _binaryOptionMarketManager;
        emit BinaryOptionMarketManagerChanged(_binaryOptionMarketManager);
    }

    function setBinaryOptionMarketMastercopy(address _binaryOptionMarketMastercopy) external onlyOwner {
        binaryOptionMarketMastercopy = _binaryOptionMarketMastercopy;
        emit BinaryOptionMarketMastercopyChanged(_binaryOptionMarketMastercopy);
    }

    function setBinaryOptionMastercopy(address _binaryOptionMastercopy) external onlyOwner {
        binaryOptionMastercopy = _binaryOptionMastercopy;
        emit BinaryOptionMastercopyChanged(_binaryOptionMastercopy);
    }

    event BinaryOptionMarketManagerChanged(address _binaryOptionMarketManager);
    event BinaryOptionMarketMastercopyChanged(address _binaryOptionMarketMastercopy);
    event BinaryOptionMastercopyChanged(address _binaryOptionMastercopy);
}

// File: synthetix-2.43.1/contracts/MinimalProxyFactory.sol



pragma solidity ^0.5.16;

// https://docs.synthetix.io/contracts/source/contracts/minimalproxyfactory
contract MinimalProxyFactory {
    function _cloneAsMinimalProxy(address _base, string memory _revertMsg) internal returns (address clone) {
        bytes memory createData = _generateMinimalProxyCreateData(_base);

        assembly {
            clone := create(
                0, // no value
                add(createData, 0x20), // data
                55 // data is always 55 bytes (10 constructor + 45 code)
            )
        }

        // If CREATE fails for some reason, address(0) is returned
        require(clone != address(0), _revertMsg);
    }

    function _generateMinimalProxyCreateData(address _base) internal pure returns (bytes memory) {
        return
            abi.encodePacked(
                //---- constructor -----
                bytes10(0x3d602d80600a3d3981f3),
                //---- proxy code -----
                bytes10(0x363d3d373d3d3d363d73),
                _base,
                bytes15(0x5af43d82803e903d91602b57fd5bf3)
            );
    }
}

// File: synthetix-2.43.1/contracts/Owned.sol



pragma solidity ^0.5.16;

// https://docs.synthetix.io/contracts/source/contracts/owned
contract Owned {
    address public owner;
    address public nominatedOwner;

    constructor(address _owner) public {
        require(_owner != address(0), "Owner address cannot be 0");
        owner = _owner;
        emit OwnerChanged(address(0), _owner);
    }

    function nominateNewOwner(address _owner) external onlyOwner {
        nominatedOwner = _owner;
        emit OwnerNominated(_owner);
    }

    function acceptOwnership() external {
        require(msg.sender == nominatedOwner, "You must be nominated before you can accept ownership");
        emit OwnerChanged(owner, nominatedOwner);
        owner = nominatedOwner;
        nominatedOwner = address(0);
    }

    modifier onlyOwner {
        _onlyOwner();
        _;
    }

    function _onlyOwner() private view {
        require(msg.sender == owner, "Only the contract owner may perform this action");
    }

    event OwnerNominated(address newOwner);
    event OwnerChanged(address oldOwner, address newOwner);
}

// File: contracts/BinaryOptionMarket.sol



pragma solidity ^0.5.16;

// Inheritance
import "synthetix-2.43.1/contracts/MinimalProxyFactory.sol";
import "./OwnedWithInit.sol";
import "./interfaces/IBinaryOptionMarket.sol";

// Libraries
import "synthetix-2.43.1/contracts/SafeDecimalMath.sol";

// Internal references
import "./BinaryOptionMarketManager.sol";
import "./BinaryOption.sol";
import "synthetix-2.43.1/contracts/interfaces/IExchangeRates.sol";
import "synthetix-2.43.1/contracts/interfaces/IERC20.sol";
import "synthetix-2.43.1/contracts/interfaces/IAddressResolver.sol";

contract BinaryOptionMarket is MinimalProxyFactory, OwnedWithInit, IBinaryOptionMarket {
    /* ========== LIBRARIES ========== */

    using SafeMath for uint;
    using SafeDecimalMath for uint;

    /* ========== TYPES ========== */

    struct Options {
        BinaryOption long;
        BinaryOption short;
    }

    struct Times {
        uint maturity;
        uint expiry;
    }

    struct OracleDetails {
        bytes32 key;
        uint strikePrice;
        uint finalPrice;
    }

    /* ========== STATE VARIABLES ========== */

    Options public options;
    Times public times;
    OracleDetails public oracleDetails;
    BinaryOptionMarketManager.Fees public fees;
    IAddressResolver public resolver;

    // `deposited` tracks the sum of all deposits minus the withheld fees.
    // This must explicitly be kept, in case tokens are transferred to the contract directly.
    uint public deposited;
    uint public accumulatedFees;
    uint public initialMint;
    address public creator;
    bool public resolved;

    uint internal _feeMultiplier;

    /* ---------- Address Resolver Configuration ---------- */

    bytes32 internal constant CONTRACT_EXRATES = "ExchangeRates";
    bytes32 internal constant CONTRACT_SYNTHSUSD = "SynthsUSD";

    /* ========== CONSTRUCTOR ========== */

    bool public initialized = false;

    function initialize(
        address _owner,
        address _binaryOptionMastercopy,
        IAddressResolver _resolver,
        address _creator,
        bytes32 _oracleKey,
        uint _strikePrice,
        uint[2] calldata _times, // [maturity, expiry]
        uint _deposit, // sUSD deposit
        uint[2] calldata _fees // [poolFee, creatorFee]
    ) external {
        require(!initialized, "Binary Option Market already initialized");
        initialized = true;
        initOwner(_owner);
        resolver = _resolver;
        creator = _creator;

        oracleDetails = OracleDetails(_oracleKey, _strikePrice, 0);
        times = Times(_times[0], _times[1]);

        deposited = _deposit;
        initialMint = _deposit;

        (uint poolFee, uint creatorFee) = (_fees[0], _fees[1]);
        fees = BinaryOptionMarketManager.Fees(poolFee, creatorFee);
        _feeMultiplier = SafeDecimalMath.unit().sub(poolFee.add(creatorFee));

        // Instantiate the options themselves
        options.long = BinaryOption(_cloneAsMinimalProxy(_binaryOptionMastercopy, "Could not create a Binary Option"));
        options.short = BinaryOption(_cloneAsMinimalProxy(_binaryOptionMastercopy, "Could not create a Binary Option"));
        // abi.encodePacked("sLONG: ", _oracleKey)
        // consider naming the option: sLongBTC>50@2021.12.31
        options.long.initialize("Binary Option Long", "sLONG");
        options.short.initialize("Binary Option Short", "sSHORT");
        _mint(creator, initialMint);

        // Note: the ERC20 base contract does not have a constructor, so we do not have to worry
        // about initializing its state separately
    }

    /* ---------- External Contracts ---------- */

    function _exchangeRates() internal view returns (IExchangeRates) {
        return IExchangeRates(resolver.requireAndGetAddress(CONTRACT_EXRATES, "ExchangeRates contract not found"));
    }

    function _sUSD() internal view returns (IERC20) {
        return IERC20(resolver.requireAndGetAddress(CONTRACT_SYNTHSUSD, "SynthsUSD contract not found"));
    }

    function _manager() internal view returns (BinaryOptionMarketManager) {
        return BinaryOptionMarketManager(owner);
    }

    /* ---------- Phases ---------- */

    function _matured() internal view returns (bool) {
        return times.maturity < block.timestamp;
    }

    function _expired() internal view returns (bool) {
        return resolved && (times.expiry < block.timestamp || deposited == 0);
    }

    function phase() external view returns (Phase) {
        if (!_matured()) {
            return Phase.Trading;
        }
        if (!_expired()) {
            return Phase.Maturity;
        }
        return Phase.Expiry;
    }

    /* ---------- Market Resolution ---------- */

    function _oraclePriceAndTimestamp() internal view returns (uint price, uint updatedAt) {
        return _exchangeRates().rateAndUpdatedTime(oracleDetails.key);
    }

    function oraclePriceAndTimestamp() external view returns (uint price, uint updatedAt) {
        return _oraclePriceAndTimestamp();
    }

    function _isFreshPriceUpdateTime(uint timestamp) internal view returns (bool) {
        (uint maxOraclePriceAge, , ) = _manager().durations();
        return (times.maturity.sub(maxOraclePriceAge)) <= timestamp;
    }

    function canResolve() external view returns (bool) {
        (, uint updatedAt) = _oraclePriceAndTimestamp();
        return !resolved && _matured() && _isFreshPriceUpdateTime(updatedAt);
    }

    function _result() internal view returns (Side) {
        uint price;
        if (resolved) {
            price = oracleDetails.finalPrice;
        } else {
            (price, ) = _oraclePriceAndTimestamp();
        }

        return oracleDetails.strikePrice <= price ? Side.Long : Side.Short;
    }

    function result() external view returns (Side) {
        return _result();
    }

    /* ---------- Option Balances and Mints ---------- */

    function _balancesOf(address account) internal view returns (uint long, uint short) {
        return (options.long.balanceOf(account), options.short.balanceOf(account));
    }

    function balancesOf(address account) external view returns (uint long, uint short) {
        return _balancesOf(account);
    }

    function totalSupplies() external view returns (uint long, uint short) {
        return (options.long.totalSupply(), options.short.totalSupply());
    }

    /* ---------- Utilities ---------- */

    function _incrementDeposited(uint value) internal returns (uint _deposited) {
        _deposited = deposited.add(value);
        deposited = _deposited;
        _manager().incrementTotalDeposited(value);
    }

    function _decrementDeposited(uint value) internal returns (uint _deposited) {
        _deposited = deposited.sub(value);
        deposited = _deposited;
        _manager().decrementTotalDeposited(value);
    }

    function _requireManagerNotPaused() internal view {
        require(!_manager().paused(), "This action cannot be performed while the contract is paused");
    }

    function requireUnpaused() external view {
        _requireManagerNotPaused();
    }

    /* ========== MUTATIVE FUNCTIONS ========== */

    /* ---------- Minting ---------- */

    function mint(uint value) external duringMinting {
        if (value == 0) {
            return;
        }

        uint valueAfterFees = value.multiplyDecimalRound(_feeMultiplier);
        uint deductedFees = value.sub(valueAfterFees);
        accumulatedFees = accumulatedFees.add(deductedFees);

        _mint(msg.sender, valueAfterFees);

        _incrementDeposited(value);
        _manager().transferSusdTo(msg.sender, address(this), value);
    }

    function _mint(address minter, uint amount) internal {
        options.long.mint(minter, amount);
        options.short.mint(minter, amount);

        emit Mint(Side.Long, minter, amount);
        emit Mint(Side.Short, minter, amount);
    }

    /* ---------- Market Resolution ---------- */

    function resolve() external onlyOwner afterMaturity managerNotPaused {
        require(!resolved, "Market already resolved");

        // We don't need to perform stale price checks, so long as the price was
        // last updated recently enough before the maturity date.
        (uint price, uint updatedAt) = _oraclePriceAndTimestamp();
        require(_isFreshPriceUpdateTime(updatedAt), "Price is stale");

        oracleDetails.finalPrice = price;
        resolved = true;

        // Now remit any collected fees.
        // Since the constructor enforces that creatorFee + poolFee < 1, the balance
        // in the contract will be sufficient to cover these transfers.
        IERC20 sUSD = _sUSD();

        uint totalFeesRatio = fees.poolFee.add(fees.creatorFee);
        uint poolFeesRatio = fees.poolFee.divideDecimalRound(totalFeesRatio);
        uint creatorFeesRatio = fees.creatorFee.divideDecimalRound(totalFeesRatio);
        uint poolFees = poolFeesRatio.multiplyDecimalRound(accumulatedFees);
        uint creatorFees = accumulatedFees.sub(poolFees);
        _decrementDeposited(creatorFees.add(poolFees));
        sUSD.transfer(_manager().feeAddress(), poolFees);
        sUSD.transfer(creator, creatorFees);

        emit MarketResolved(_result(), price, updatedAt, deposited, poolFees, creatorFees);
    }

    /* ---------- Claiming and Exercising Options ---------- */

    function exerciseOptions() external afterMaturity returns (uint) {
        // The market must be resolved if it has not been.
        // the first one to exercise pays the gas fees. Might be worth splitting it up.
        if (!resolved) {
            _manager().resolveMarket(address(this));
        }

        // If the account holds no options, revert.
        (uint longBalance, uint shortBalance) = _balancesOf(msg.sender);
        require(longBalance != 0 || shortBalance != 0, "Nothing to exercise");

        // Each option only needs to be exercised if the account holds any of it.
        if (longBalance != 0) {
            options.long.exercise(msg.sender);
        }
        if (shortBalance != 0) {
            options.short.exercise(msg.sender);
        }

        // Only pay out the side that won.
        uint payout = (_result() == Side.Long) ? longBalance : shortBalance;
        emit OptionsExercised(msg.sender, payout);
        if (payout != 0) {
            _decrementDeposited(payout);
            _sUSD().transfer(msg.sender, payout);
        }
        return payout;
    }

    /* ---------- Market Expiry ---------- */

    function _selfDestruct(address payable beneficiary) internal {
        uint _deposited = deposited;
        if (_deposited != 0) {
            _decrementDeposited(_deposited);
        }

        // Transfer the balance rather than the deposit value in case there are any synths left over
        // from direct transfers.
        IERC20 sUSD = _sUSD();
        uint balance = sUSD.balanceOf(address(this));
        if (balance != 0) {
            sUSD.transfer(beneficiary, balance);
        }

        // Destroy the option tokens before destroying the market itself.
        options.long.expire(beneficiary);
        options.short.expire(beneficiary);
        selfdestruct(beneficiary);
    }

    function expire(address payable beneficiary) external onlyOwner {
        require(_expired(), "Unexpired options remaining");
        _selfDestruct(beneficiary);
    }

    /* ========== MODIFIERS ========== */

    modifier duringMinting() {
        require(!_matured(), "Minting inactive");
        _;
    }

    modifier afterMaturity() {
        require(_matured(), "Not yet mature");
        _;
    }

    modifier managerNotPaused() {
        _requireManagerNotPaused();
        _;
    }

    /* ========== EVENTS ========== */

    event Mint(Side side, address indexed account, uint value);
    event MarketResolved(
        Side result,
        uint oraclePrice,
        uint oracleTimestamp,
        uint deposited,
        uint poolFees,
        uint creatorFees
    );
    event OptionsExercised(address indexed account, uint value);
}

// File: synthetix-2.43.1/contracts/interfaces/IAddressResolver.sol



pragma solidity >=0.4.24;

// https://docs.synthetix.io/contracts/source/interfaces/iaddressresolver
interface IAddressResolver {
    function getAddress(bytes32 name) external view returns (address);

    function getSynth(bytes32 key) external view returns (address);

    function requireAndGetAddress(bytes32 name, string calldata reason) external view returns (address);
}

// File: contracts/OwnedWithInit.sol



pragma solidity ^0.5.16;

contract OwnedWithInit {
    address public owner;
    address public nominatedOwner;

    constructor() public {}

    function initOwner(address _owner) internal {
        require(owner == address(0), "Init can only be called when owner is 0");
        owner = _owner;
        emit OwnerChanged(address(0), _owner);
    }

    function nominateNewOwner(address _owner) external onlyOwner {
        nominatedOwner = _owner;
        emit OwnerNominated(_owner);
    }

    function acceptOwnership() external {
        require(msg.sender == nominatedOwner, "You must be nominated before you can accept ownership");
        emit OwnerChanged(owner, nominatedOwner);
        owner = nominatedOwner;
        nominatedOwner = address(0);
    }

    modifier onlyOwner {
        _onlyOwner();
        _;
    }

    function _onlyOwner() private view {
        require(msg.sender == owner, "Only the contract owner may perform this action");
    }

    event OwnerNominated(address newOwner);
    event OwnerChanged(address oldOwner, address newOwner);
}

// File: contracts/interfaces/IBinaryOptionMarket.sol



pragma solidity >=0.4.24;

import "../interfaces/IBinaryOptionMarketManager.sol";
import "../interfaces/IBinaryOption.sol";

interface IBinaryOptionMarket {
    /* ========== TYPES ========== */

    enum Phase {Trading, Maturity, Expiry}
    enum Side {Long, Short}

    /* ========== VIEWS / VARIABLES ========== */

    function options() external view returns (IBinaryOption long, IBinaryOption short);

    function times()
        external
        view
        returns (
            uint maturity,
            uint destructino
        );

    function oracleDetails()
        external
        view
        returns (
            bytes32 key,
            uint strikePrice,
            uint finalPrice
        );

    function fees()
        external
        view
        returns (
            uint poolFee,
            uint creatorFee
        );

    function deposited() external view returns (uint);

    function accumulatedFees() external view returns (uint);

    function creator() external view returns (address);

    function resolved() external view returns (bool);

    function phase() external view returns (Phase);

    function oraclePriceAndTimestamp() external view returns (uint price, uint updatedAt);

    function canResolve() external view returns (bool);

    function result() external view returns (Side);

    function balancesOf(address account) external view returns (uint long, uint short);

    function totalSupplies() external view returns (uint long, uint short);

    /* ========== MUTATIVE FUNCTIONS ========== */

    function mint(uint value) external;

    function exerciseOptions() external returns (uint);
}

// File: synthetix-2.43.1/contracts/SafeDecimalMath.sol



pragma solidity ^0.5.16;

// Libraries
import "openzeppelin-solidity-2.3.0/contracts/math/SafeMath.sol";

// https://docs.synthetix.io/contracts/source/libraries/safedecimalmath
library SafeDecimalMath {
    using SafeMath for uint;

    /* Number of decimal places in the representations. */
    uint8 public constant decimals = 18;
    uint8 public constant highPrecisionDecimals = 27;

    /* The number representing 1.0. */
    uint public constant UNIT = 10**uint(decimals);

    /* The number representing 1.0 for higher fidelity numbers. */
    uint public constant PRECISE_UNIT = 10**uint(highPrecisionDecimals);
    uint private constant UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR = 10**uint(highPrecisionDecimals - decimals);

    /**
     * @return Provides an interface to UNIT.
     */
    function unit() external pure returns (uint) {
        return UNIT;
    }

    /**
     * @return Provides an interface to PRECISE_UNIT.
     */
    function preciseUnit() external pure returns (uint) {
        return PRECISE_UNIT;
    }

    /**
     * @return The result of multiplying x and y, interpreting the operands as fixed-point
     * decimals.
     *
     * @dev A unit factor is divided out after the product of x and y is evaluated,
     * so that product must be less than 2**256. As this is an integer division,
     * the internal division always rounds down. This helps save on gas. Rounding
     * is more expensive on gas.
     */
    function multiplyDecimal(uint x, uint y) internal pure returns (uint) {
        /* Divide by UNIT to remove the extra factor introduced by the product. */
        return x.mul(y) / UNIT;
    }

    /**
     * @return The result of safely multiplying x and y, interpreting the operands
     * as fixed-point decimals of the specified precision unit.
     *
     * @dev The operands should be in the form of a the specified unit factor which will be
     * divided out after the product of x and y is evaluated, so that product must be
     * less than 2**256.
     *
     * Unlike multiplyDecimal, this function rounds the result to the nearest increment.
     * Rounding is useful when you need to retain fidelity for small decimal numbers
     * (eg. small fractions or percentages).
     */
    function _multiplyDecimalRound(
        uint x,
        uint y,
        uint precisionUnit
    ) private pure returns (uint) {
        /* Divide by UNIT to remove the extra factor introduced by the product. */
        uint quotientTimesTen = x.mul(y) / (precisionUnit / 10);

        if (quotientTimesTen % 10 >= 5) {
            quotientTimesTen += 10;
        }

        return quotientTimesTen / 10;
    }

    /**
     * @return The result of safely multiplying x and y, interpreting the operands
     * as fixed-point decimals of a precise unit.
     *
     * @dev The operands should be in the precise unit factor which will be
     * divided out after the product of x and y is evaluated, so that product must be
     * less than 2**256.
     *
     * Unlike multiplyDecimal, this function rounds the result to the nearest increment.
     * Rounding is useful when you need to retain fidelity for small decimal numbers
     * (eg. small fractions or percentages).
     */
    function multiplyDecimalRoundPrecise(uint x, uint y) internal pure returns (uint) {
        return _multiplyDecimalRound(x, y, PRECISE_UNIT);
    }

    /**
     * @return The result of safely multiplying x and y, interpreting the operands
     * as fixed-point decimals of a standard unit.
     *
     * @dev The operands should be in the standard unit factor which will be
     * divided out after the product of x and y is evaluated, so that product must be
     * less than 2**256.
     *
     * Unlike multiplyDecimal, this function rounds the result to the nearest increment.
     * Rounding is useful when you need to retain fidelity for small decimal numbers
     * (eg. small fractions or percentages).
     */
    function multiplyDecimalRound(uint x, uint y) internal pure returns (uint) {
        return _multiplyDecimalRound(x, y, UNIT);
    }

    /**
     * @return The result of safely dividing x and y. The return value is a high
     * precision decimal.
     *
     * @dev y is divided after the product of x and the standard precision unit
     * is evaluated, so the product of x and UNIT must be less than 2**256. As
     * this is an integer division, the result is always rounded down.
     * This helps save on gas. Rounding is more expensive on gas.
     */
    function divideDecimal(uint x, uint y) internal pure returns (uint) {
        /* Reintroduce the UNIT factor that will be divided out by y. */
        return x.mul(UNIT).div(y);
    }

    /**
     * @return The result of safely dividing x and y. The return value is as a rounded
     * decimal in the precision unit specified in the parameter.
     *
     * @dev y is divided after the product of x and the specified precision unit
     * is evaluated, so the product of x and the specified precision unit must
     * be less than 2**256. The result is rounded to the nearest increment.
     */
    function _divideDecimalRound(
        uint x,
        uint y,
        uint precisionUnit
    ) private pure returns (uint) {
        uint resultTimesTen = x.mul(precisionUnit * 10).div(y);

        if (resultTimesTen % 10 >= 5) {
            resultTimesTen += 10;
        }

        return resultTimesTen / 10;
    }

    /**
     * @return The result of safely dividing x and y. The return value is as a rounded
     * standard precision decimal.
     *
     * @dev y is divided after the product of x and the standard precision unit
     * is evaluated, so the product of x and the standard precision unit must
     * be less than 2**256. The result is rounded to the nearest increment.
     */
    function divideDecimalRound(uint x, uint y) internal pure returns (uint) {
        return _divideDecimalRound(x, y, UNIT);
    }

    /**
     * @return The result of safely dividing x and y. The return value is as a rounded
     * high precision decimal.
     *
     * @dev y is divided after the product of x and the high precision unit
     * is evaluated, so the product of x and the high precision unit must
     * be less than 2**256. The result is rounded to the nearest increment.
     */
    function divideDecimalRoundPrecise(uint x, uint y) internal pure returns (uint) {
        return _divideDecimalRound(x, y, PRECISE_UNIT);
    }

    /**
     * @dev Convert a standard decimal representation to a high precision one.
     */
    function decimalToPreciseDecimal(uint i) internal pure returns (uint) {
        return i.mul(UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR);
    }

    /**
     * @dev Convert a high precision decimal to a standard decimal representation.
     */
    function preciseDecimalToDecimal(uint i) internal pure returns (uint) {
        uint quotientTimesTen = i / (UNIT_TO_HIGH_PRECISION_CONVERSION_FACTOR / 10);

        if (quotientTimesTen % 10 >= 5) {
            quotientTimesTen += 10;
        }

        return quotientTimesTen / 10;
    }
}

// File: contracts/BinaryOptionMarketManager.sol



pragma solidity ^0.5.16;

// Inheritance
import "./interfaces/IBinaryOptionMarketManager.sol";
import "synthetix-2.43.1/contracts/Owned.sol";
import "synthetix-2.43.1/contracts/Pausable.sol";

// Libraries
import "synthetix-2.43.1/contracts/AddressSetLib.sol";
import "synthetix-2.43.1/contracts/SafeDecimalMath.sol";

// Internal references
import "./BinaryOptionMarketFactory.sol";
import "./BinaryOptionMarket.sol";
import "./BinaryOption.sol";
import "./interfaces/IBinaryOptionMarket.sol";
import "synthetix-2.43.1/contracts/interfaces/IExchangeRates.sol";
import "synthetix-2.43.1/contracts/interfaces/IERC20.sol";
import "synthetix-2.43.1/contracts/interfaces/IAddressResolver.sol";

contract BinaryOptionMarketManager is Owned, Pausable, IBinaryOptionMarketManager {
    /* ========== LIBRARIES ========== */

    using SafeMath for uint;
    using AddressSetLib for AddressSetLib.AddressSet;

    /* ========== TYPES ========== */

    struct Fees {
        uint poolFee;
        uint creatorFee;
    }

    struct Durations {
        uint maxOraclePriceAge;
        uint expiryDuration;
        uint maxTimeToMaturity;
    }

    /* ========== STATE VARIABLES ========== */

    address public feeAddress;

    Fees public fees;
    Durations public durations;
    uint public capitalRequirement;

    bool public marketCreationEnabled = true;
    uint public totalDeposited;

    AddressSetLib.AddressSet internal _activeMarkets;
    AddressSetLib.AddressSet internal _maturedMarkets;

    BinaryOptionMarketManager internal _migratingManager;

    IAddressResolver public resolver;

    address public binaryOptionMarketFactory;

    /* ---------- Address Resolver Configuration ---------- */

    bytes32 internal constant CONTRACT_SYNTHSUSD = "SynthsUSD";
    bytes32 internal constant CONTRACT_EXRATES = "ExchangeRates";

    /* ========== CONSTRUCTOR ========== */

    constructor(
        address _owner,
        IAddressResolver _resolver,
        uint _maxOraclePriceAge,
        uint _expiryDuration,
        uint _maxTimeToMaturity,
        uint _creatorCapitalRequirement,
        uint _poolFee,
        uint _creatorFee,
        address _feeAddress
    ) public Owned(_owner) Pausable() {
        resolver = _resolver;

        // Temporarily change the owner so that the setters don't revert.
        owner = msg.sender;

        setFeeAddress(_feeAddress);
        setExpiryDuration(_expiryDuration);
        setMaxOraclePriceAge(_maxOraclePriceAge);
        setMaxTimeToMaturity(_maxTimeToMaturity);
        setCreatorCapitalRequirement(_creatorCapitalRequirement);
        setPoolFee(_poolFee);
        setCreatorFee(_creatorFee);
        owner = _owner;
    }

    /* ========== SETTERS ========== */
    function setBinaryOptionsMarketFactory(address _binaryOptionMarketFactory) external onlyOwner {
        binaryOptionMarketFactory = _binaryOptionMarketFactory;
    }

    function setFeeAddress(address _feeAddress) public onlyOwner {
        feeAddress = _feeAddress;
    }

    /* ========== VIEWS ========== */

    /* ---------- Related Contracts ---------- */

    function _sUSD() internal view returns (IERC20) {
        return IERC20(resolver.requireAndGetAddress(CONTRACT_SYNTHSUSD, "Synth sUSD contract not found"));
    }

    function _exchangeRates() internal view returns (IExchangeRates) {
        return IExchangeRates(resolver.requireAndGetAddress(CONTRACT_EXRATES, "ExchangeRates contract not found"));
    }

    /* ---------- Market Information ---------- */

    function _isKnownMarket(address candidate) internal view returns (bool) {
        return _activeMarkets.contains(candidate) || _maturedMarkets.contains(candidate);
    }

    function numActiveMarkets() external view returns (uint) {
        return _activeMarkets.elements.length;
    }

    function activeMarkets(uint index, uint pageSize) external view returns (address[] memory) {
        return _activeMarkets.getPage(index, pageSize);
    }

    function numMaturedMarkets() external view returns (uint) {
        return _maturedMarkets.elements.length;
    }

    function maturedMarkets(uint index, uint pageSize) external view returns (address[] memory) {
        return _maturedMarkets.getPage(index, pageSize);
    }

    function _isValidKey(bytes32 oracleKey) internal view returns (bool) {
        IExchangeRates exchangeRates = _exchangeRates();

        // If it has a rate, then it's possibly a valid key
        if (exchangeRates.rateForCurrency(oracleKey) != 0) {
            // But not sUSD
            if (oracleKey == "sUSD") {
                return false;
            }

            // and not inverse rates
            (uint entryPoint, , , , ) = exchangeRates.inversePricing(oracleKey);
            if (entryPoint != 0) {
                return false;
            }

            return true;
        }

        return false;
    }

    /* ========== MUTATIVE FUNCTIONS ========== */

    /* ---------- Setters ---------- */

    function setMaxOraclePriceAge(uint _maxOraclePriceAge) public onlyOwner {
        durations.maxOraclePriceAge = _maxOraclePriceAge;
        emit MaxOraclePriceAgeUpdated(_maxOraclePriceAge);
    }

    function setExpiryDuration(uint _expiryDuration) public onlyOwner {
        durations.expiryDuration = _expiryDuration;
        emit ExpiryDurationUpdated(_expiryDuration);
    }

    function setMaxTimeToMaturity(uint _maxTimeToMaturity) public onlyOwner {
        durations.maxTimeToMaturity = _maxTimeToMaturity;
        emit MaxTimeToMaturityUpdated(_maxTimeToMaturity);
    }

    function setPoolFee(uint _poolFee) public onlyOwner {
        uint totalFee = _poolFee + fees.creatorFee;
        require(totalFee < SafeDecimalMath.unit(), "Total fee must be less than 100%.");
        require(0 < totalFee, "Total fee must be nonzero.");
        fees.poolFee = _poolFee;
        emit PoolFeeUpdated(_poolFee);
    }

    function setCreatorFee(uint _creatorFee) public onlyOwner {
        uint totalFee = _creatorFee + fees.poolFee;
        require(totalFee < SafeDecimalMath.unit(), "Total fee must be less than 100%.");
        require(0 < totalFee, "Total fee must be nonzero.");
        fees.creatorFee = _creatorFee;
        emit CreatorFeeUpdated(_creatorFee);
    }

    function setCreatorCapitalRequirement(uint _creatorCapitalRequirement) public onlyOwner {
        capitalRequirement = _creatorCapitalRequirement;
        emit CreatorCapitalRequirementUpdated(_creatorCapitalRequirement);
    }

    /* ---------- Deposit Management ---------- */

    function incrementTotalDeposited(uint delta) external onlyActiveMarkets notPaused {
        totalDeposited = totalDeposited.add(delta);
    }

    function decrementTotalDeposited(uint delta) external onlyKnownMarkets notPaused {
        // NOTE: As individual market debt is not tracked here, the underlying markets
        //       need to be careful never to subtract more debt than they added.
        //       This can't be enforced without additional state/communication overhead.
        totalDeposited = totalDeposited.sub(delta);
    }

    /* ---------- Market Lifecycle ---------- */

    function createMarket(
        bytes32 oracleKey,
        uint strikePrice,
        uint maturity,
        uint initialMint // initial sUSD to mint options for
    )
        external
        notPaused
        returns (
            IBinaryOptionMarket // no support for returning BinaryOptionMarket polymorphically given the interface
        )
    {
        require(marketCreationEnabled, "Market creation is disabled");
        require(_isValidKey(oracleKey), "Invalid key");

        require(maturity <= block.timestamp + durations.maxTimeToMaturity, "Maturity too far in the future");
        uint expiry = maturity.add(durations.expiryDuration);

        require(block.timestamp < maturity, "Maturity has to be in the future");
        // We also require maturity < expiry. But there is no need to check this.
        // Fees being in range are checked in the setters.
        // The market itself validates the capital and skew requirements.

        require(capitalRequirement <= initialMint, "Insufficient capital");

        BinaryOptionMarket market =
            BinaryOptionMarketFactory(binaryOptionMarketFactory).createMarket(
                msg.sender,
                resolver,
                oracleKey,
                strikePrice,
                [maturity, expiry],
                initialMint,
                [fees.poolFee, fees.creatorFee]
            );
        _activeMarkets.add(address(market));

        // The debt can't be incremented in the new market's constructor because until construction is complete,
        // the manager doesn't know its address in order to grant it permission.
        totalDeposited = totalDeposited.add(initialMint);
        _sUSD().transferFrom(msg.sender, address(market), initialMint);

        (BinaryOption long, BinaryOption short) = market.options();

        emit MarketCreated(
            address(market),
            msg.sender,
            oracleKey,
            strikePrice,
            maturity,
            expiry,
            address(long),
            address(short)
        );
        return market;
    }

    function transferSusdTo(
        address sender,
        address receiver,
        uint amount
    ) external {
        //only to be called by markets themselves
        require(_isKnownMarket(address(msg.sender)), "Market unknown.");
        _sUSD().transferFrom(sender, receiver, amount);
    }

    function resolveMarket(address market) external {
        require(_activeMarkets.contains(market), "Not an active market");
        BinaryOptionMarket(market).resolve();
        _activeMarkets.remove(market);
        _maturedMarkets.add(market);
    }

    function expireMarkets(address[] calldata markets) external notPaused onlyOwner {
        for (uint i = 0; i < markets.length; i++) {
            address market = markets[i];

            require(_isKnownMarket(address(market)), "Market unknown.");

            // The market itself handles decrementing the total deposits.
            BinaryOptionMarket(market).expire(msg.sender);

            // Note that we required that the market is known, which guarantees
            // its index is defined and that the list of markets is not empty.
            _maturedMarkets.remove(market);

            emit MarketExpired(market);
        }
    }

    function setMarketCreationEnabled(bool enabled) public onlyOwner {
        if (enabled != marketCreationEnabled) {
            marketCreationEnabled = enabled;
            emit MarketCreationEnabledUpdated(enabled);
        }
    }

    function setMigratingManager(BinaryOptionMarketManager manager) public onlyOwner {
        _migratingManager = manager;
    }

    function migrateMarkets(
        BinaryOptionMarketManager receivingManager,
        bool active,
        BinaryOptionMarket[] calldata marketsToMigrate
    ) external onlyOwner {
        require(address(receivingManager) != address(this), "Can't migrate to self");

        uint _numMarkets = marketsToMigrate.length;
        if (_numMarkets == 0) {
            return;
        }
        AddressSetLib.AddressSet storage markets = active ? _activeMarkets : _maturedMarkets;

        uint runningDepositTotal;
        for (uint i; i < _numMarkets; i++) {
            BinaryOptionMarket market = marketsToMigrate[i];
            require(_isKnownMarket(address(market)), "Market unknown.");

            // Remove it from our list and deposit total.
            markets.remove(address(market));
            runningDepositTotal = runningDepositTotal.add(market.deposited());

            // Prepare to transfer ownership to the new manager.
            market.nominateNewOwner(address(receivingManager));
        }
        // Deduct the total deposits of the migrated markets.
        totalDeposited = totalDeposited.sub(runningDepositTotal);
        emit MarketsMigrated(receivingManager, marketsToMigrate);

        // Now actually transfer the markets over to the new manager.
        receivingManager.receiveMarkets(active, marketsToMigrate);
    }

    function receiveMarkets(bool active, BinaryOptionMarket[] calldata marketsToReceive) external {
        require(msg.sender == address(_migratingManager), "Only permitted for migrating manager.");

        uint _numMarkets = marketsToReceive.length;
        if (_numMarkets == 0) {
            return;
        }
        AddressSetLib.AddressSet storage markets = active ? _activeMarkets : _maturedMarkets;

        uint runningDepositTotal;
        for (uint i; i < _numMarkets; i++) {
            BinaryOptionMarket market = marketsToReceive[i];
            require(!_isKnownMarket(address(market)), "Market already known.");

            market.acceptOwnership();
            markets.add(address(market));
            // Update the market with the new manager address,
            runningDepositTotal = runningDepositTotal.add(market.deposited());
        }
        totalDeposited = totalDeposited.add(runningDepositTotal);
        emit MarketsReceived(_migratingManager, marketsToReceive);
    }

    /* ========== MODIFIERS ========== */

    modifier onlyActiveMarkets() {
        require(_activeMarkets.contains(msg.sender), "Permitted only for active markets.");
        _;
    }

    modifier onlyKnownMarkets() {
        require(_isKnownMarket(msg.sender), "Permitted only for known markets.");
        _;
    }

    /* ========== EVENTS ========== */

    event MarketCreated(
        address market,
        address indexed creator,
        bytes32 indexed oracleKey,
        uint strikePrice,
        uint maturityDate,
        uint expiryDate,
        address long,
        address short
    );
    event MarketExpired(address market);
    event MarketsMigrated(BinaryOptionMarketManager receivingManager, BinaryOptionMarket[] markets);
    event MarketsReceived(BinaryOptionMarketManager migratingManager, BinaryOptionMarket[] markets);
    event MarketCreationEnabledUpdated(bool enabled);
    event MaxOraclePriceAgeUpdated(uint duration);
    event ExpiryDurationUpdated(uint duration);
    event MaxTimeToMaturityUpdated(uint duration);
    event CreatorCapitalRequirementUpdated(uint value);
    event PoolFeeUpdated(uint fee);
    event CreatorFeeUpdated(uint fee);
}

// File: contracts/BinaryOption.sol



pragma solidity ^0.5.16;

// Inheritance
import "synthetix-2.43.1/contracts/interfaces/IERC20.sol";
import "./interfaces/IBinaryOption.sol";

// Libraries
import "synthetix-2.43.1/contracts/SafeDecimalMath.sol";

// Internal references
import "./BinaryOptionMarket.sol";

contract BinaryOption is IERC20, IBinaryOption {
    /* ========== LIBRARIES ========== */

    using SafeMath for uint;
    using SafeDecimalMath for uint;

    /* ========== STATE VARIABLES ========== */

    string public name;
    string public symbol;
    uint8 public constant decimals = 18;

    BinaryOptionMarket public market;

    mapping(address => uint) public balanceOf;
    uint public totalSupply;

    // The argument order is allowance[owner][spender]
    mapping(address => mapping(address => uint)) public allowance;

    // Enforce a 1 cent minimum amount
    uint internal constant _MINIMUM_AMOUNT = 1e16;

    /* ========== CONSTRUCTOR ========== */

    bool public initialized = false;

    function initialize(
        string calldata _name,
        string calldata _symbol
    ) external {
        require(!initialized, "Binary Option Market already initialized");
        initialized = true;
        name = _name;
        symbol = _symbol;
        market = BinaryOptionMarket(msg.sender);
    }

    /* ========== MUTATIVE FUNCTIONS ========== */

    function _requireMinimumAmount(uint amount) internal pure returns (uint) {
        require(amount >= _MINIMUM_AMOUNT || amount == 0, "Balance < $0.01");
        return amount;
    }

    function mint(address minter, uint amount) external onlyMarket {
        _requireMinimumAmount(amount);
        totalSupply = totalSupply.add(amount);
        balanceOf[minter] = balanceOf[minter].add(amount); // Increment rather than assigning since a transfer may have occurred.

        emit Transfer(address(0), minter, amount);
        emit Issued(minter, amount);
    }

    // This must only be invoked after maturity.
    function exercise(address claimant) external onlyMarket {
        uint balance = balanceOf[claimant];

        if (balance == 0) {
            return;
        }

        balanceOf[claimant] = 0;
        totalSupply = totalSupply.sub(balance);

        emit Transfer(claimant, address(0), balance);
        emit Burned(claimant, balance);
    }

    // This must only be invoked after the exercise window is complete.
    // Note that any options which have not been exercised will linger.
    function expire(address payable beneficiary) external onlyMarket {
        selfdestruct(beneficiary);
    }

    /* ---------- ERC20 Functions ---------- */

    function _transfer(
        address _from,
        address _to,
        uint _value
    ) internal returns (bool success) {
        market.requireUnpaused();
        require(_to != address(0) && _to != address(this), "Invalid address");

        uint fromBalance = balanceOf[_from];
        require(_value <= fromBalance, "Insufficient balance");

        balanceOf[_from] = fromBalance.sub(_value);
        balanceOf[_to] = balanceOf[_to].add(_value);

        emit Transfer(_from, _to, _value);
        return true;
    }

    function transfer(address _to, uint _value) external returns (bool success) {
        return _transfer(msg.sender, _to, _value);
    }

    function transferFrom(
        address _from,
        address _to,
        uint _value
    ) external returns (bool success) {
        uint fromAllowance = allowance[_from][msg.sender];
        require(_value <= fromAllowance, "Insufficient allowance");

        allowance[_from][msg.sender] = fromAllowance.sub(_value);
        return _transfer(_from, _to, _value);
    }

    function approve(address _spender, uint _value) external returns (bool success) {
        require(_spender != address(0));
        allowance[msg.sender][_spender] = _value;
        emit Approval(msg.sender, _spender, _value);
        return true;
    }

    /* ========== MODIFIERS ========== */

    modifier onlyMarket() {
        require(msg.sender == address(market), "Only market allowed");
        _;
    }

    /* ========== EVENTS ========== */

    event Issued(address indexed account, uint value);
    event Burned(address indexed account, uint value);
    event Transfer(address indexed from, address indexed to, uint value);
    event Approval(address indexed owner, address indexed spender, uint value);
}

// File: synthetix-2.43.1/contracts/interfaces/IExchangeRates.sol



pragma solidity >=0.4.24;

// https://docs.synthetix.io/contracts/source/interfaces/iexchangerates
interface IExchangeRates {
    // Structs
    struct RateAndUpdatedTime {
        uint216 rate;
        uint40 time;
    }

    struct InversePricing {
        uint entryPoint;
        uint upperLimit;
        uint lowerLimit;
        bool frozenAtUpperLimit;
        bool frozenAtLowerLimit;
    }

    // Views
    function aggregators(bytes32 currencyKey) external view returns (address);

    function aggregatorWarningFlags() external view returns (address);

    function anyRateIsInvalid(bytes32[] calldata currencyKeys) external view returns (bool);

    function canFreezeRate(bytes32 currencyKey) external view returns (bool);

    function currentRoundForRate(bytes32 currencyKey) external view returns (uint);

    function currenciesUsingAggregator(address aggregator) external view returns (bytes32[] memory);

    function effectiveValue(
        bytes32 sourceCurrencyKey,
        uint sourceAmount,
        bytes32 destinationCurrencyKey
    ) external view returns (uint value);

    function effectiveValueAndRates(
        bytes32 sourceCurrencyKey,
        uint sourceAmount,
        bytes32 destinationCurrencyKey
    )
        external
        view
        returns (
            uint value,
            uint sourceRate,
            uint destinationRate
        );

    function effectiveValueAtRound(
        bytes32 sourceCurrencyKey,
        uint sourceAmount,
        bytes32 destinationCurrencyKey,
        uint roundIdForSrc,
        uint roundIdForDest
    ) external view returns (uint value);

    function getCurrentRoundId(bytes32 currencyKey) external view returns (uint);

    function getLastRoundIdBeforeElapsedSecs(
        bytes32 currencyKey,
        uint startingRoundId,
        uint startingTimestamp,
        uint timediff
    ) external view returns (uint);

    function inversePricing(bytes32 currencyKey)
        external
        view
        returns (
            uint entryPoint,
            uint upperLimit,
            uint lowerLimit,
            bool frozenAtUpperLimit,
            bool frozenAtLowerLimit
        );

    function lastRateUpdateTimes(bytes32 currencyKey) external view returns (uint256);

    function oracle() external view returns (address);

    function rateAndTimestampAtRound(bytes32 currencyKey, uint roundId) external view returns (uint rate, uint time);

    function rateAndUpdatedTime(bytes32 currencyKey) external view returns (uint rate, uint time);

    function rateAndInvalid(bytes32 currencyKey) external view returns (uint rate, bool isInvalid);

    function rateForCurrency(bytes32 currencyKey) external view returns (uint);

    function rateIsFlagged(bytes32 currencyKey) external view returns (bool);

    function rateIsFrozen(bytes32 currencyKey) external view returns (bool);

    function rateIsInvalid(bytes32 currencyKey) external view returns (bool);

    function rateIsStale(bytes32 currencyKey) external view returns (bool);

    function rateStalePeriod() external view returns (uint);

    function ratesAndUpdatedTimeForCurrencyLastNRounds(bytes32 currencyKey, uint numRounds)
        external
        view
        returns (uint[] memory rates, uint[] memory times);

    function ratesAndInvalidForCurrencies(bytes32[] calldata currencyKeys)
        external
        view
        returns (uint[] memory rates, bool anyRateInvalid);

    function ratesForCurrencies(bytes32[] calldata currencyKeys) external view returns (uint[] memory);

    // Mutative functions
    function freezeRate(bytes32 currencyKey) external;
}

// File: synthetix-2.43.1/contracts/interfaces/IERC20.sol



pragma solidity >=0.4.24;

// https://docs.synthetix.io/contracts/source/interfaces/ierc20
interface IERC20 {
    // ERC20 Optional Views
    function name() external view returns (string memory);

    function symbol() external view returns (string memory);

    function decimals() external view returns (uint8);

    // Views
    function totalSupply() external view returns (uint);

    function balanceOf(address owner) external view returns (uint);

    function allowance(address owner, address spender) external view returns (uint);

    // Mutative functions
    function transfer(address to, uint value) external returns (bool);

    function approve(address spender, uint value) external returns (bool);

    function transferFrom(
        address from,
        address to,
        uint value
    ) external returns (bool);

    // Events
    event Transfer(address indexed from, address indexed to, uint value);

    event Approval(address indexed owner, address indexed spender, uint value);
}

// File: contracts/interfaces/IBinaryOptionMarketManager.sol



pragma solidity >=0.4.24;

import "../interfaces/IBinaryOptionMarket.sol";

interface IBinaryOptionMarketManager {
    /* ========== VIEWS / VARIABLES ========== */

    function fees() external view returns (uint poolFee, uint creatorFee);

    function durations()
        external
        view
        returns (
            uint maxOraclePriceAge,
            uint expiryDuration,
            uint maxTimeToMaturity
        );

    function capitalRequirement() external view returns (uint);

    function marketCreationEnabled() external view returns (bool);

    function totalDeposited() external view returns (uint);

    function numActiveMarkets() external view returns (uint);

    function activeMarkets(uint index, uint pageSize) external view returns (address[] memory);

    function numMaturedMarkets() external view returns (uint);

    function maturedMarkets(uint index, uint pageSize) external view returns (address[] memory);

    /* ========== MUTATIVE FUNCTIONS ========== */

    function createMarket(
        bytes32 oracleKey,
        uint strikePrice,
        uint maturity,
        uint initialMint // initial sUSD to mint options for
    ) external returns (IBinaryOptionMarket);

    function resolveMarket(address market) external;

    function expireMarkets(address[] calldata market) external;

    function transferSusdTo(address sender, address receiver, uint amount) external;
}

// File: contracts/interfaces/IBinaryOption.sol



pragma solidity >=0.4.24;

import "../interfaces/IBinaryOptionMarket.sol";
import "synthetix-2.43.1/contracts/interfaces/IERC20.sol";

interface IBinaryOption {
    /* ========== VIEWS / VARIABLES ========== */

    function market() external view returns (IBinaryOptionMarket);

    function balanceOf(address account) external view returns (uint);

    function totalSupply() external view returns (uint);

}

// File: openzeppelin-solidity-2.3.0/contracts/math/SafeMath.sol



pragma solidity ^0.5.0;

/**
 * @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) {
        require(b <= a, "SafeMath: subtraction overflow");
        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-solidity/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) {
        // Solidity only automatically asserts when dividing by 0
        require(b > 0, "SafeMath: division by zero");
        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) {
        require(b != 0, "SafeMath: modulo by zero");
        return a % b;
    }
}

// File: synthetix-2.43.1/contracts/Pausable.sol



pragma solidity ^0.5.16;

// Inheritance
import "./Owned.sol";

// https://docs.synthetix.io/contracts/source/contracts/pausable
contract Pausable is Owned {
    uint public lastPauseTime;
    bool public paused;

    constructor() internal {
        // This contract is abstract, and thus cannot be instantiated directly
        require(owner != address(0), "Owner must be set");
        // Paused will be false, and lastPauseTime will be 0 upon initialisation
    }

    /**
     * @notice Change the paused state of the contract
     * @dev Only the contract owner may call this.
     */
    function setPaused(bool _paused) external onlyOwner {
        // Ensure we're actually changing the state before we do anything
        if (_paused == paused) {
            return;
        }

        // Set our paused state.
        paused = _paused;

        // If applicable, set the last pause time.
        if (paused) {
            lastPauseTime = now;
        }

        // Let everyone know that our pause state has changed.
        emit PauseChanged(paused);
    }

    event PauseChanged(bool isPaused);

    modifier notPaused {
        require(!paused, "This action cannot be performed while the contract is paused");
        _;
    }
}

// File: synthetix-2.43.1/contracts/AddressSetLib.sol



pragma solidity ^0.5.16;

// https://docs.synthetix.io/contracts/source/libraries/addresssetlib/
library AddressSetLib {
    struct AddressSet {
        address[] elements;
        mapping(address => uint) indices;
    }

    function contains(AddressSet storage set, address candidate) internal view returns (bool) {
        if (set.elements.length == 0) {
            return false;
        }
        uint index = set.indices[candidate];
        return index != 0 || set.elements[0] == candidate;
    }

    function getPage(
        AddressSet storage set,
        uint index,
        uint pageSize
    ) internal view returns (address[] memory) {
        // NOTE: This implementation should be converted to slice operators if the compiler is updated to v0.6.0+
        uint endIndex = index + pageSize; // The check below that endIndex <= index handles overflow.

        // If the page extends past the end of the list, truncate it.
        if (endIndex > set.elements.length) {
            endIndex = set.elements.length;
        }
        if (endIndex <= index) {
            return new address[](0);
        }

        uint n = endIndex - index; // We already checked for negative overflow.
        address[] memory page = new address[](n);
        for (uint i; i < n; i++) {
            page[i] = set.elements[i + index];
        }
        return page;
    }

    function add(AddressSet storage set, address element) internal {
        // Adding to a set is an idempotent operation.
        if (!contains(set, element)) {
            set.indices[element] = set.elements.length;
            set.elements.push(element);
        }
    }

    function remove(AddressSet storage set, address element) internal {
        require(contains(set, element), "Element not in set.");
        // Replace the removed element with the last element of the list.
        uint index = set.indices[element];
        uint lastIndex = set.elements.length - 1; // We required that element is in the list, so it is not empty.
        if (index != lastIndex) {
            // No need to shift the last element if it is the one we want to delete.
            address shiftedElement = set.elements[lastIndex];
            set.elements[index] = shiftedElement;
            set.indices[shiftedElement] = index;
        }
        set.elements.pop();
        delete set.indices[element];
    }
}