import {BigNumber} from 'bignumber.js';
import * as _ from 'lodash';
import * as Web3 from 'web3';
import {TokenWrapper} from '../contract_wrappers/token_wrapper';
import {BlockParamLiteral} from '../types';
/**
* Copy on read store for balances/proxyAllowances of tokens/accounts
*/
export class BalanceAndProxyAllowanceLazyStore {
private token: TokenWrapper;
private defaultBlock: BlockParamLiteral;
private balance: {
[tokenAddress: string]: {
[userAddress: string]: BigNumber;
};
};
private proxyAllowance: {
[tokenAddress: string]: {
[userAddress: string]: BigNumber;
};
};
constructor(token: TokenWrapper, defaultBlock: BlockParamLiteral) {
this.token = token;
this.defaultBlock = defaultBlock;
this.balance = {};
this.proxyAllowance = {};
}
public async getBalanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber> {
if (_.isUndefined(this.balance[tokenAddress]) || _.isUndefined(this.balance[tokenAddress][userAddress])) {
const methodOpts = {
defaultBlock: this.defaultBlock,
};
const balance = await this.token.getBalanceAsync(tokenAddress, userAddress, methodOpts);
this.setBalance(tokenAddress, userAddress, balance);
}
const cachedBalance = this.balance[tokenAddress][userAddress];
return cachedBalance;
}
public setBalance(tokenAddress: string, userAddress: string, balance: BigNumber): void {
if (_.isUndefined(this.balance[tokenAddress])) {
this.balance[tokenAddress] = {};
}
this.balance[tokenAddress][userAddress] = balance;
}
public deleteBalance(tokenAddress: string, userAddress: string): void {
if (!_.isUndefined(this.balance[tokenAddress])) {
delete this.balance[tokenAddress][userAddress];
if (_.isEmpty(this.balance[tokenAddress])) {
delete this.balance[tokenAddress];
}
}
}
public async getProxyAllowanceAsync(tokenAddress: string, userAddress: string): Promise<BigNumber> {
if (_.isUndefined(this.proxyAllowance[tokenAddress]) ||
_.isUndefined(this.proxyAllowance[tokenAddress][userAddress])) {
const methodOpts = {
defaultBlock: this.defaultBlock,
};
const proxyAllowance = await this.token.getProxyAllowanceAsync(tokenAddress, userAddress, methodOpts);
this.setProxyAllowance(tokenAddress, userAddress, proxyAllowance);
}
const cachedProxyAllowance = this.proxyAllowance[tokenAddress][userAddress];
return cachedProxyAllowance;
}
public setProxyAllowance(tokenAddress: string, userAddress: string, proxyAllowance: BigNumber): void {
if (_.isUndefined(this.proxyAllowance[tokenAddress])) {
this.proxyAllowance[tokenAddress] = {};
}
this.proxyAllowance[tokenAddress][userAddress] = proxyAllowance;
}
public deleteProxyAllowance(tokenAddress: string, userAddress: string): void {
if (!_.isUndefined(this.proxyAllowance[tokenAddress])) {
delete this.proxyAllowance[tokenAddress][userAddress];
if (_.isEmpty(this.proxyAllowance[tokenAddress])) {
delete this.proxyAllowance[tokenAddress];
}
}
}
public deleteAll(): void {
this.balance = {};
this.proxyAllowance = {};
}
}