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Diffstat (limited to 'packages/contracts/src/utils/asset_wrapper.ts')
-rw-r--r-- | packages/contracts/src/utils/asset_wrapper.ts | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/packages/contracts/src/utils/asset_wrapper.ts b/packages/contracts/src/utils/asset_wrapper.ts new file mode 100644 index 000000000..2eb54f290 --- /dev/null +++ b/packages/contracts/src/utils/asset_wrapper.ts @@ -0,0 +1,187 @@ +import { assetProxyUtils } from '@0xproject/order-utils'; +import { BigNumber, errorUtils } from '@0xproject/utils'; +import * as _ from 'lodash'; + +import { AbstractAssetWrapper } from '../abstract/abstract_asset_wrapper'; + +import { constants } from './constants'; +import { ERC20Wrapper } from './erc20_wrapper'; +import { ERC721Wrapper } from './erc721_wrapper'; + +interface ProxyIdToAssetWrappers { + [proxyId: number]: AbstractAssetWrapper; +} + +/** + * This class abstracts away the differences between ERC20 and ERC721 tokens so that + * the logic that uses it does not need to care what standard a token belongs to. + */ +export class AssetWrapper { + private _proxyIdToAssetWrappers: ProxyIdToAssetWrappers; + constructor(assetWrappers: AbstractAssetWrapper[]) { + this._proxyIdToAssetWrappers = {}; + _.each(assetWrappers, assetWrapper => { + const proxyId = assetWrapper.getProxyId(); + this._proxyIdToAssetWrappers[proxyId] = assetWrapper; + }); + } + public async getBalanceAsync(userAddress: string, assetData: string): Promise<BigNumber> { + const proxyId = assetProxyUtils.decodeAssetDataId(assetData); + switch (proxyId) { + case constants.ERC20_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC20Wrapper; + const balance = await assetWrapper.getBalanceAsync(userAddress, assetData); + return balance; + } + case constants.ERC721_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC721Wrapper; + const assetProxyData = assetProxyUtils.decodeERC721AssetData(assetData); + const isOwner = await assetWrapper.isOwnerAsync( + userAddress, + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + const balance = isOwner ? new BigNumber(1) : new BigNumber(0); + return balance; + } + default: + throw errorUtils.spawnSwitchErr('proxyId', proxyId); + } + } + public async setBalanceAsync(userAddress: string, assetData: string, desiredBalance: BigNumber): Promise<void> { + const proxyId = assetProxyUtils.decodeAssetDataId(assetData); + switch (proxyId) { + case constants.ERC20_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC20Wrapper; + await assetWrapper.setBalanceAsync(userAddress, assetData, desiredBalance); + return; + } + case constants.ERC721_PROXY_ID: { + if (!desiredBalance.eq(0) && !desiredBalance.eq(1)) { + throw new Error(`Balance for ERC721 token can only be set to 0 or 1. Got: ${desiredBalance}`); + } + const erc721Wrapper = this._proxyIdToAssetWrappers[proxyId] as ERC721Wrapper; + const assetProxyData = assetProxyUtils.decodeERC721AssetData(assetData); + const doesTokenExist = erc721Wrapper.doesTokenExistAsync( + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + if (!doesTokenExist && desiredBalance.eq(1)) { + await erc721Wrapper.mintAsync(assetProxyData.tokenAddress, assetProxyData.tokenId, userAddress); + return; + } else if (!doesTokenExist && desiredBalance.eq(0)) { + return; // noop + } + const tokenOwner = await erc721Wrapper.ownerOfAsync( + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + if (userAddress !== tokenOwner && desiredBalance.eq(1)) { + await erc721Wrapper.transferFromAsync( + assetProxyData.tokenAddress, + assetProxyData.tokenId, + tokenOwner, + userAddress, + ); + } else if (tokenOwner === userAddress && desiredBalance.eq(0)) { + // Burn token + await erc721Wrapper.burnAsync(assetProxyData.tokenAddress, assetProxyData.tokenId, userAddress); + return; + } + break; + } + default: + throw errorUtils.spawnSwitchErr('proxyId', proxyId); + } + } + public async getProxyAllowanceAsync(userAddress: string, assetData: string): Promise<BigNumber> { + const proxyId = assetProxyUtils.decodeAssetDataId(assetData); + switch (proxyId) { + case constants.ERC20_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC20Wrapper; + const allowance = await assetWrapper.getProxyAllowanceAsync(userAddress, assetData); + return allowance; + } + case constants.ERC721_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC721Wrapper; + const erc721ProxyData = assetProxyUtils.decodeERC721AssetData(assetData); + const isProxyApproved = await assetWrapper.isProxyApprovedAsync( + erc721ProxyData.tokenAddress, + erc721ProxyData.tokenId, + ); + const isProxyApprovedForAllAsync = await assetWrapper.isProxyApprovedForAllAsync( + userAddress, + erc721ProxyData.tokenAddress, + erc721ProxyData.tokenId, + ); + const allowance = isProxyApproved || isProxyApprovedForAllAsync ? new BigNumber(1) : new BigNumber(0); + return allowance; + } + default: + throw errorUtils.spawnSwitchErr('proxyId', proxyId); + } + } + public async setProxyAllowanceAsync( + userAddress: string, + assetData: string, + desiredAllowance: BigNumber, + ): Promise<void> { + const proxyId = assetProxyUtils.decodeAssetDataId(assetData); + switch (proxyId) { + case constants.ERC20_PROXY_ID: { + const assetWrapper = this._proxyIdToAssetWrappers[proxyId] as ERC20Wrapper; + await assetWrapper.setAllowanceAsync(userAddress, assetData, desiredAllowance); + return; + } + case constants.ERC721_PROXY_ID: { + if (!desiredAllowance.eq(0) && !desiredAllowance.eq(1)) { + throw new Error(`Allowance for ERC721 token can only be set to 0 or 1. Got: ${desiredAllowance}`); + } + const erc721Wrapper = this._proxyIdToAssetWrappers[proxyId] as ERC721Wrapper; + const assetProxyData = assetProxyUtils.decodeERC721AssetData(assetData); + + const doesTokenExist = await erc721Wrapper.doesTokenExistAsync( + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + if (!doesTokenExist) { + throw new Error( + `Cannot setProxyAllowance on non-existent token: ${assetProxyData.tokenAddress} ${ + assetProxyData.tokenId + }`, + ); + } + const isProxyApprovedForAll = await erc721Wrapper.isProxyApprovedForAllAsync( + userAddress, + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + // HACK: We do not currently support ApprovedForAll when setting proxy allowance + // This was intentional since unsetting ApprovedForAll, will unset approval for unrelated + // tokens other then the one specified in the call to this method. + if (isProxyApprovedForAll) { + throw new Error(`We don't currently support the use of "approveAll" functionality for ERC721.`); + } + + const isProxyApproved = await erc721Wrapper.isProxyApprovedAsync( + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + if (!isProxyApproved && desiredAllowance.eq(1)) { + await erc721Wrapper.approveProxyAsync(assetProxyData.tokenAddress, assetProxyData.tokenId); + } else if (isProxyApproved && desiredAllowance.eq(0)) { + // Remove approval + await erc721Wrapper.approveAsync( + constants.NULL_ADDRESS, + assetProxyData.tokenAddress, + assetProxyData.tokenId, + ); + } + + break; + } + default: + throw errorUtils.spawnSwitchErr('proxyId', proxyId); + } + } +} |