import { SignedOrder } from '@0xproject/types';
import { BigNumber } from '@0xproject/utils';
import * as _ from 'lodash';
import { ZeroEx } from '../0x';
import { ExchangeWrapper } from '../contract_wrappers/exchange_wrapper';
import { BalanceAndProxyAllowanceFetcher } from '../abstract/balance_and_proxy_allowance_fetcher';
import { OrderFilledCancelledFetcher } from '../abstract/order_filled_cancelled_fetcher';
import { RemainingFillableCalculator } from '../order_watcher/remaining_fillable_calculator';
import { ExchangeContractErrs, OrderRelevantState, OrderState, OrderStateInvalid, OrderStateValid } from '../types';
const ACCEPTABLE_RELATIVE_ROUNDING_ERROR = 0.0001;
export class OrderStateUtils {
private _balanceAndProxyAllowanceFetcher: BalanceAndProxyAllowanceFetcher;
private _orderFilledCancelledFetcher: OrderFilledCancelledFetcher;
private static _validateIfOrderIsValid(signedOrder: SignedOrder, orderRelevantState: OrderRelevantState): void {
const unavailableTakerTokenAmount = orderRelevantState.cancelledTakerTokenAmount.add(
orderRelevantState.filledTakerTokenAmount,
);
const availableTakerTokenAmount = signedOrder.takerTokenAmount.minus(unavailableTakerTokenAmount);
if (availableTakerTokenAmount.eq(0)) {
throw new Error(ExchangeContractErrs.OrderRemainingFillAmountZero);
}
if (orderRelevantState.makerBalance.eq(0)) {
throw new Error(ExchangeContractErrs.InsufficientMakerBalance);
}
if (orderRelevantState.makerProxyAllowance.eq(0)) {
throw new Error(ExchangeContractErrs.InsufficientMakerAllowance);
}
if (!signedOrder.makerFee.eq(0)) {
if (orderRelevantState.makerFeeBalance.eq(0)) {
throw new Error(ExchangeContractErrs.InsufficientMakerFeeBalance);
}
if (orderRelevantState.makerFeeProxyAllowance.eq(0)) {
throw new Error(ExchangeContractErrs.InsufficientMakerFeeAllowance);
}
}
const minFillableTakerTokenAmountWithinNoRoundingErrorRange = signedOrder.takerTokenAmount
.dividedBy(ACCEPTABLE_RELATIVE_ROUNDING_ERROR)
.dividedBy(signedOrder.makerTokenAmount);
if (
orderRelevantState.remainingFillableTakerTokenAmount.lessThan(
minFillableTakerTokenAmountWithinNoRoundingErrorRange,
)
) {
throw new Error(ExchangeContractErrs.OrderFillRoundingError);
}
}
constructor(
balanceAndProxyAllowanceFetcher: BalanceAndProxyAllowanceFetcher,
orderFilledCancelledFetcher: OrderFilledCancelledFetcher,
) {
this._balanceAndProxyAllowanceFetcher = balanceAndProxyAllowanceFetcher;
this._orderFilledCancelledFetcher = orderFilledCancelledFetcher;
}
public async getOrderStateAsync(signedOrder: SignedOrder): Promise<OrderState> {
const orderRelevantState = await this.getOrderRelevantStateAsync(signedOrder);
const orderHash = ZeroEx.getOrderHashHex(signedOrder);
try {
OrderStateUtils._validateIfOrderIsValid(signedOrder, orderRelevantState);
const orderState: OrderStateValid = {
isValid: true,
orderHash,
orderRelevantState,
};
return orderState;
} catch (err) {
const orderState: OrderStateInvalid = {
isValid: false,
orderHash,
error: err.message,
};
return orderState;
}
}
public async getOrderRelevantStateAsync(signedOrder: SignedOrder): Promise<OrderRelevantState> {
// HACK: We access the private property here but otherwise the interface will be less nice.
// If we pass it from the instantiator - there is no opportunity to get it there
// because JS doesn't support async constructors.
// Moreover - it's cached under the hood so it's equivalent to an async constructor.
const exchange = (this._orderFilledCancelledFetcher as any)._exchangeWrapper as ExchangeWrapper;
const zrxTokenAddress = exchange.getZRXTokenAddress();
const orderHash = ZeroEx.getOrderHashHex(signedOrder);
const makerBalance = await this._balanceAndProxyAllowanceFetcher.getBalanceAsync(
signedOrder.makerTokenAddress,
signedOrder.maker,
);
const makerProxyAllowance = await this._balanceAndProxyAllowanceFetcher.getProxyAllowanceAsync(
signedOrder.makerTokenAddress,
signedOrder.maker,
);
const makerFeeBalance = await this._balanceAndProxyAllowanceFetcher.getBalanceAsync(
zrxTokenAddress,
signedOrder.maker,
);
const makerFeeProxyAllowance = await this._balanceAndProxyAllowanceFetcher.getProxyAllowanceAsync(
zrxTokenAddress,
signedOrder.maker,
);
const filledTakerTokenAmount = await this._orderFilledCancelledFetcher.getFilledTakerAmountAsync(orderHash);
const cancelledTakerTokenAmount = await this._orderFilledCancelledFetcher.getCancelledTakerAmountAsync(
orderHash,
);
const unavailableTakerTokenAmount = await exchange.getUnavailableTakerAmountAsync(orderHash);
const totalMakerTokenAmount = signedOrder.makerTokenAmount;
const totalTakerTokenAmount = signedOrder.takerTokenAmount;
const remainingTakerTokenAmount = totalTakerTokenAmount.minus(unavailableTakerTokenAmount);
const remainingMakerTokenAmount = remainingTakerTokenAmount
.times(totalMakerTokenAmount)
.dividedToIntegerBy(totalTakerTokenAmount);
const transferrableMakerTokenAmount = BigNumber.min([makerProxyAllowance, makerBalance]);
const transferrableFeeTokenAmount = BigNumber.min([makerFeeProxyAllowance, makerFeeBalance]);
const isMakerTokenZRX = signedOrder.makerTokenAddress === zrxTokenAddress;
const remainingFillableCalculator = new RemainingFillableCalculator(
signedOrder,
isMakerTokenZRX,
transferrableMakerTokenAmount,
transferrableFeeTokenAmount,
remainingMakerTokenAmount,
);
const remainingFillableMakerTokenAmount = remainingFillableCalculator.computeRemainingMakerFillable();
const remainingFillableTakerTokenAmount = remainingFillableCalculator.computeRemainingTakerFillable();
const orderRelevantState = {
makerBalance,
makerProxyAllowance,
makerFeeBalance,
makerFeeProxyAllowance,
filledTakerTokenAmount,
cancelledTakerTokenAmount,
remainingFillableMakerTokenAmount,
remainingFillableTakerTokenAmount,
};
return orderRelevantState;
}
}