feat: add wallet entity and wallet factory

Get current user balances (Eth, POLY, or any other ERC20 token)

Author: shuffledex

src/entities/Wallet.ts

@@ -0,0 +1,94 @@
+import { BigNumber, ContractWrapper } from '@polymathnetwork/contract-wrappers';
+import { Entity } from './Entity';
+import { serialize, unserialize } from '../utils';
+import { PolymathError } from '../PolymathError';
+import { ErrorCode } from '../types';
+import { Context } from '../Context';
+import { PolymathBase } from '../PolymathBase';
+
+export interface UniqueIdentifier {
+  address: string;
+}
+
+function isUniqueIdentifier(identifier: any): identifier is UniqueIdentifier {
+  const { address } = identifier;
+
+  return typeof address === 'string';
+}
+
+export interface Params extends UniqueIdentifier {}
+
+export class Wallet extends Entity<Params> {
+  public static generateId({ address }: UniqueIdentifier) {
+    return serialize('wallet', {
+      address,
+    });
+  }
+
+  public static unserialize(serialized: string) {
+    const unserialized = unserialize(serialized);
+
+    if (!isUniqueIdentifier(unserialized)) {
+      throw new PolymathError({
+        code: ErrorCode.InvalidUuid,
+        message: 'Wrong Wallet ID format.',
+      });
+    }
+
+    return unserialized;
+  }
+
+  public uid: string;
+
+  public address: string;
+
+  private contractWrappers: PolymathBase;
+
+  constructor(params: Params & UniqueIdentifier, context: Context) {
+    super();
+
+    const { address } = params;
+    const { contractWrappers } = context;
+
+    this.address = address;
+    this.contractWrappers = contractWrappers;
+    this.uid = Wallet.generateId({
+      address,
+    });
+  }
+
+  public toPojo() {
+    const { uid, address } = this;
+
+    return {
+      uid,
+      address,
+    };
+  }
+
+  public _refresh(params: Partial<Params>) {
+    const { address } = params;
+
+    if (address) {
+      this.address = address;
+    }
+  }
+
+  public getPolyBalance = async (): Promise<BigNumber> => {
+    const { address } = this;
+    return await this.contractWrappers.getBalance({ address });
+  };
+
+  public getEthBalance = async (): Promise<BigNumber> => {
+    return await this.contractWrappers.polyToken.balanceOf();
+  };
+
+  public getErc20Balance = async (tokenAddress: string): Promise<BigNumber> => {
+    const erc20Wrapper = await this.contractWrappers.getERC20TokenWrapper({
+      address: tokenAddress,
+    });
+
+    const { address } = this;
+    return await erc20Wrapper.balanceOf({ owner: address });
+  };
+}

src/entities/factories/WalletFactory.ts

@@ -0,0 +1,17 @@
+import { Factory } from './Factory';
+import { Context } from '../../Context';
+import { Wallet, Params, UniqueIdentifier } from '../Wallet';
+
+export class WalletFactory extends Factory<Wallet, Params, UniqueIdentifier> {
+  protected generateProperties = async (uid: string) => {
+    const { address } = Wallet.unserialize(uid);
+
+    return {
+      address,
+    };
+  };
+
+  constructor(context: Context) {
+    super(Wallet, context);
+  }
+}

src/entities/index.ts

@@ -15,3 +15,4 @@ export { UsdTieredSto } from './UsdTieredSto';
 export { Investment } from './Investment';
 export { Sto } from './Sto';
 export { Shareholder } from './Shareholder';
+export { Wallet } from './Wallet';