IExchanger.sol

pragma solidity >=0.4.24;
pragma experimental ABIEncoderV2;
import "./IVirtualSynth.sol";

// https://docs.synthetix.io/contracts/source/interfaces/iexchanger
interface IExchanger {
    struct ExchangeEntrySettlement {
        bytes32 src;
        uint amount;
        bytes32 dest;
        uint reclaim;
        uint rebate;
        uint srcRoundIdAtPeriodEnd;
        uint destRoundIdAtPeriodEnd;
        uint timestamp;
    }

    struct ExchangeEntry {
        uint sourceRate;
        uint destinationRate;
        uint destinationAmount;
        uint exchangeFeeRate;
        uint exchangeDynamicFeeRate;
        uint roundIdForSrc;
        uint roundIdForDest;
        uint sourceAmountAfterSettlement;
    }

    // Views
    function calculateAmountAfterSettlement(
        address from,
        bytes32 currencyKey,
        uint amount,
        uint refunded
    ) external view returns (uint amountAfterSettlement);

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

    function maxSecsLeftInWaitingPeriod(address account, bytes32 currencyKey) external view returns (uint);

    function settlementOwing(address account, bytes32 currencyKey)
        external
        view
        returns (
            uint reclaimAmount,
            uint rebateAmount,
            uint numEntries
        );

    function hasWaitingPeriodOrSettlementOwing(address account, bytes32 currencyKey) external view returns (bool);

    function feeRateForExchange(bytes32 sourceCurrencyKey, bytes32 destinationCurrencyKey) external view returns (uint);

    function dynamicFeeRateForExchange(bytes32 sourceCurrencyKey, bytes32 destinationCurrencyKey)
        external
        view
        returns (uint feeRate, bool tooVolatile);

    function getAmountsForExchange(
        uint sourceAmount,
        bytes32 sourceCurrencyKey,
        bytes32 destinationCurrencyKey
    )
        external
        view
        returns (
            uint amountReceived,
            uint fee,
            uint exchangeFeeRate
        );

    function priceDeviationThresholdFactor() external view returns (uint);

    function waitingPeriodSecs() external view returns (uint);

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

    // Mutative functions
    function exchange(
        address exchangeForAddress,
        address from,
        bytes32 sourceCurrencyKey,
        uint sourceAmount,
        bytes32 destinationCurrencyKey,
        address destinationAddress,
        bool virtualSynth,
        address rewardAddress,
        bytes32 trackingCode
    ) external returns (uint amountReceived, IVirtualSynth vSynth);

    function exchangeAtomically(
        address from,
        bytes32 sourceCurrencyKey,
        uint sourceAmount,
        bytes32 destinationCurrencyKey,
        address destinationAddress,
        bytes32 trackingCode,
        uint minAmount
    ) external returns (uint amountReceived);

    function settle(address from, bytes32 currencyKey)
        external
        returns (
            uint reclaimed,
            uint refunded,
            uint numEntries
        );
}

// Used to have strongly-typed access to internal mutative functions in Synthetix
interface ISynthetixInternal {
    function emitExchangeTracking(
        bytes32 trackingCode,
        bytes32 toCurrencyKey,
        uint256 toAmount,
        uint256 fee
    ) external;

    function emitSynthExchange(
        address account,
        bytes32 fromCurrencyKey,
        uint fromAmount,
        bytes32 toCurrencyKey,
        uint toAmount,
        address toAddress
    ) external;

    function emitAtomicSynthExchange(
        address account,
        bytes32 fromCurrencyKey,
        uint fromAmount,
        bytes32 toCurrencyKey,
        uint toAmount,
        address toAddress
    ) external;

    function emitExchangeReclaim(
        address account,
        bytes32 currencyKey,
        uint amount
    ) external;

    function emitExchangeRebate(
        address account,
        bytes32 currencyKey,
        uint amount
    ) external;
}

interface IExchangerInternalDebtCache {
    function updateCachedSynthDebtsWithRates(bytes32[] calldata currencyKeys, uint[] calldata currencyRates) external;

    function updateCachedSynthDebts(bytes32[] calldata currencyKeys) external;
}