import { DutchAuctionContract } from '@0x/abi-gen-wrappers';
import { DutchAuction } from '@0x/contract-artifacts';
import { schemas } from '@0x/json-schemas';
import { assetDataUtils } from '@0x/order-utils';
import { DutchAuctionDetails, SignedOrder } from '@0x/types';
import { BigNumber } from '@0x/utils';
import { Web3Wrapper } from '@0x/web3-wrapper';
import { ContractAbi } from 'ethereum-types';
import * as ethAbi from 'ethereumjs-abi';
import * as ethUtil from 'ethereumjs-util';
import * as _ from 'lodash';
import { orderTxOptsSchema } from '../schemas/order_tx_opts_schema';
import { txOptsSchema } from '../schemas/tx_opts_schema';
import { DutchAuctionData, DutchAuctionWrapperError, OrderTransactionOpts } from '../types';
import { assert } from '../utils/assert';
import { _getDefaultContractAddresses } from '../utils/contract_addresses';
import { ContractWrapper } from './contract_wrapper';
export class DutchAuctionWrapper extends ContractWrapper {
public abi: ContractAbi = DutchAuction.compilerOutput.abi;
public address: string;
private _dutchAuctionContractIfExists?: DutchAuctionContract;
/**
* Dutch auction details are encoded with the asset data for a 0x order. This function produces a hex
* encoded assetData string, containing information both about the asset being traded and the
* dutch auction; which is usable in the makerAssetData or takerAssetData fields in a 0x order.
* @param assetData Hex encoded assetData string for the asset being auctioned.
* @param beginTimeSeconds Begin time of the dutch auction.
* @param beginAmount Starting amount being sold in the dutch auction.
* @return The hex encoded assetData string.
*/
public static encodeDutchAuctionAssetData(
assetData: string,
beginTimeSeconds: BigNumber,
beginAmount: BigNumber,
): string {
const assetDataBuffer = ethUtil.toBuffer(assetData);
const abiEncodedAuctionData = (ethAbi as any).rawEncode(
['uint256', 'uint256'],
[beginTimeSeconds.toString(), beginAmount.toString()],
);
const abiEncodedAuctionDataBuffer = ethUtil.toBuffer(abiEncodedAuctionData);
const dutchAuctionDataBuffer = Buffer.concat([assetDataBuffer, abiEncodedAuctionDataBuffer]);
const dutchAuctionData = ethUtil.bufferToHex(dutchAuctionDataBuffer);
return dutchAuctionData;
}
/**
* Dutch auction details are encoded with the asset data for a 0x order. This function decodes a hex
* encoded assetData string, containing information both about the asset being traded and the
* dutch auction.
* @param dutchAuctionData Hex encoded assetData string for the asset being auctioned.
* @return An object containing the auction asset, auction begin time and auction begin amount.
*/
public static decodeDutchAuctionData(dutchAuctionData: string): DutchAuctionData {
const dutchAuctionDataBuffer = ethUtil.toBuffer(dutchAuctionData);
// Decode asset data
const dutchAuctionDataLengthInBytes = 64;
const assetDataBuffer = dutchAuctionDataBuffer.slice(
0,
dutchAuctionDataBuffer.byteLength - dutchAuctionDataLengthInBytes,
);
const assetDataHex = ethUtil.bufferToHex(assetDataBuffer);
const assetData = assetDataUtils.decodeAssetDataOrThrow(assetDataHex);
// Decode auction details
const dutchAuctionDetailsBuffer = dutchAuctionDataBuffer.slice(
dutchAuctionDataBuffer.byteLength - dutchAuctionDataLengthInBytes,
);
const [beginTimeSecondsAsBN, beginAmountAsBN] = ethAbi.rawDecode(
['uint256', 'uint256'],
dutchAuctionDetailsBuffer,
);
const beginTimeSeconds = new BigNumber(`0x${beginTimeSecondsAsBN.toString()}`);
const beginAmount = new BigNumber(`0x${beginAmountAsBN.toString()}`);
return {
assetData,
beginTimeSeconds,
beginAmount,
};
}
/**
* Instantiate DutchAuctionWrapper
* @param web3Wrapper Web3Wrapper instance to use.
* @param networkId Desired networkId.
* @param address The address of the Dutch Auction contract. If undefined, will
* default to the known address corresponding to the networkId.
*/
public constructor(web3Wrapper: Web3Wrapper, networkId: number, address?: string) {
super(web3Wrapper, networkId);
this.address = _.isUndefined(address) ? _getDefaultContractAddresses(networkId).dutchAuction : address;
}
/**
* Matches the buy and sell orders at an amount given the following: the current block time, the auction
* start time and the auction begin amount. The sell order is a an order at the lowest amount
* at the end of the auction. Excess from the match is transferred to the seller.
* Over time the price moves from beginAmount to endAmount given the current block.timestamp.
* @param buyOrder The Buyer's order. This order is for the current expected price of the auction.
* @param sellOrder The Seller's order. This order is for the lowest amount (at the end of the auction).
* @param takerAddress The user Ethereum address who would like to fill this order. Must be available via the supplied
* Provider provided at instantiation.
* @return Transaction hash.
*/
public async matchOrdersAsync(
buyOrder: SignedOrder,
sellOrder: SignedOrder,
takerAddress: string,
orderTransactionOpts: OrderTransactionOpts = { shouldValidate: true },
): Promise<string> {
// type assertions
assert.doesConformToSchema('buyOrder', buyOrder, schemas.signedOrderSchema);
assert.doesConformToSchema('sellOrder', sellOrder, schemas.signedOrderSchema);
await assert.isSenderAddressAsync('takerAddress', takerAddress, this._web3Wrapper);
assert.doesConformToSchema('orderTransactionOpts', orderTransactionOpts, orderTxOptsSchema, [txOptsSchema]);
const normalizedTakerAddress = takerAddress.toLowerCase();
// other assertions
if (
sellOrder.makerAssetData !== buyOrder.takerAssetData ||
sellOrder.takerAssetData !== buyOrder.makerAssetData
) {
throw new Error(DutchAuctionWrapperError.AssetDataMismatch);
}
// get contract
const dutchAuctionInstance = await this._getDutchAuctionContractAsync();
// validate transaction
if (orderTransactionOpts.shouldValidate) {
await dutchAuctionInstance.matchOrders.callAsync(
buyOrder,
sellOrder,
buyOrder.signature,
sellOrder.signature,
{
from: normalizedTakerAddress,
gas: orderTransactionOpts.gasLimit,
gasPrice: orderTransactionOpts.gasPrice,
nonce: orderTransactionOpts.nonce,
},
);
}
// send transaction
const txHash = await dutchAuctionInstance.matchOrders.sendTransactionAsync(
buyOrder,
sellOrder,
buyOrder.signature,
sellOrder.signature,
{
from: normalizedTakerAddress,
gas: orderTransactionOpts.gasLimit,
gasPrice: orderTransactionOpts.gasPrice,
nonce: orderTransactionOpts.nonce,
},
);
return txHash;
}
/**
* Fetches the Auction Details for the given order
* @param sellOrder The Seller's order. This order is for the lowest amount (at the end of the auction).
* @return The dutch auction details.
*/
public async getAuctionDetailsAsync(sellOrder: SignedOrder): Promise<DutchAuctionDetails> {
// type assertions
assert.doesConformToSchema('sellOrder', sellOrder, schemas.signedOrderSchema);
// get contract
const dutchAuctionInstance = await this._getDutchAuctionContractAsync();
// call contract
const auctionDetails = await dutchAuctionInstance.getAuctionDetails.callAsync(sellOrder);
return auctionDetails;
}
private async _getDutchAuctionContractAsync(): Promise<DutchAuctionContract> {
if (!_.isUndefined(this._dutchAuctionContractIfExists)) {
return this._dutchAuctionContractIfExists;
}
const contractInstance = new DutchAuctionContract(
this.abi,
this.address,
this._web3Wrapper.getProvider(),
this._web3Wrapper.getContractDefaults(),
);
this._dutchAuctionContractIfExists = contractInstance;
return this._dutchAuctionContractIfExists;
}
}
