1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
|
import { AssetProxyId, ERC20AssetData, ERC721AssetData } from '@0xproject/types';
import { BigNumber } from '@0xproject/utils';
import BN = require('bn.js');
import ethAbi = require('ethereumjs-abi');
import ethUtil = require('ethereumjs-util');
import { constants } from './constants';
export const assetDataUtils = {
encodeERC20AssetData(tokenAddress: string): string {
return ethUtil.bufferToHex(ethAbi.simpleEncode('ERC20Token(address)', tokenAddress));
},
decodeERC20AssetData(assetData: string): ERC20AssetData {
const data = ethUtil.toBuffer(assetData);
if (data.byteLength < constants.ERC20_ASSET_DATA_BYTE_LENGTH) {
throw new Error(
`Could not decode ERC20 Proxy Data. Expected length of encoded data to be at least ${
constants.ERC20_ASSET_DATA_BYTE_LENGTH
}. Got ${data.byteLength}`,
);
}
const assetProxyId = ethUtil.bufferToHex(data.slice(0, constants.SELECTOR_LENGTH));
if (assetProxyId !== AssetProxyId.ERC20) {
throw new Error(
`Could not decode ERC20 Proxy Data. Expected Asset Proxy Id to be ERC20 (${
AssetProxyId.ERC20
}), but got ${assetProxyId}`,
);
}
const [tokenAddress] = ethAbi.rawDecode(['address'], data.slice(constants.SELECTOR_LENGTH));
return {
assetProxyId,
tokenAddress: ethUtil.addHexPrefix(tokenAddress),
};
},
encodeERC721AssetData(tokenAddress: string, tokenId: BigNumber, receiverData?: string): string {
// TODO: Pass `tokendId` as a BigNumber.
return ethUtil.bufferToHex(
ethAbi.simpleEncode(
'ERC721Token(address,uint256,bytes)',
tokenAddress,
`0x${tokenId.toString(constants.BASE_16)}`,
ethUtil.toBuffer(receiverData || '0x'),
),
);
},
decodeERC721AssetData(assetData: string): ERC721AssetData {
const data = ethUtil.toBuffer(assetData);
if (data.byteLength < constants.ERC721_ASSET_DATA_MINIMUM_BYTE_LENGTH) {
throw new Error(
`Could not decode ERC721 Asset Data. Expected length of encoded data to be at least ${
constants.ERC721_ASSET_DATA_MINIMUM_BYTE_LENGTH
}. Got ${data.byteLength}`,
);
}
const assetProxyId = ethUtil.bufferToHex(data.slice(0, constants.SELECTOR_LENGTH));
if (assetProxyId !== AssetProxyId.ERC721) {
throw new Error(
`Could not decode ERC721 Asset Data. Expected Asset Proxy Id to be ERC721 (${
AssetProxyId.ERC721
}), but got ${assetProxyId}`,
);
}
const [tokenAddress, tokenId, receiverData] = ethAbi.rawDecode(
['address', 'uint256', 'bytes'],
data.slice(constants.SELECTOR_LENGTH),
);
return {
assetProxyId,
tokenAddress: ethUtil.addHexPrefix(tokenAddress),
tokenId: new BigNumber(tokenId.toString()),
receiverData: ethUtil.bufferToHex(receiverData),
};
},
decodeAssetDataId(assetData: string): AssetProxyId {
const encodedAssetData = ethUtil.toBuffer(assetData);
if (encodedAssetData.byteLength < constants.SELECTOR_LENGTH) {
throw new Error(
`Could not decode Proxy Data. Expected length of encoded data to be at least 4. Got ${
encodedAssetData.byteLength
}`,
);
}
const encodedAssetProxyId = encodedAssetData.slice(0, constants.SELECTOR_LENGTH);
const assetProxyId = decodeAssetProxyId(encodedAssetProxyId);
return assetProxyId;
},
decodeAssetData(assetData: string): ERC20AssetData | ERC721AssetData {
const assetProxyId = assetDataUtils.decodeAssetDataId(assetData);
switch (assetProxyId) {
case AssetProxyId.ERC20:
const erc20AssetData = assetDataUtils.decodeERC20AssetData(assetData);
return erc20AssetData;
case AssetProxyId.ERC721:
const erc721AssetData = assetDataUtils.decodeERC721AssetData(assetData);
return erc721AssetData;
default:
throw new Error(`Unrecognized asset proxy id: ${assetProxyId}`);
}
},
};
function decodeAssetProxyId(encodedAssetProxyId: Buffer): AssetProxyId {
const hexString = ethUtil.bufferToHex(encodedAssetProxyId);
if (hexString === AssetProxyId.ERC20) {
return AssetProxyId.ERC20;
}
if (hexString === AssetProxyId.ERC721) {
return AssetProxyId.ERC721;
}
throw new Error(`Invalid ProxyId: ${hexString}`);
}
|
