[wip]: add L2 chains support #8 #7

src/bridge/WBGL.ts

@@ -1,37 +1,42 @@
-import Web3 from 'web3'
+import { ethers, Wallet } from 'ethers'
 import fetch from 'node-fetch'
-import abi from '../abi/WBGL.json'
-import { IBridgeConfig } from '../types'
-import { ChaindIds } from '../chains'
 import { IContracts } from '.'
+import WBGL_ABI from '../abi/WBGL'
+import { ChaindIds } from '../chains'
+import { IBridgeConfig } from '../types'
+import { WBGL_CONTRACT_ADDRESS_BNB, WBGL_CONTRACT_ADDRESS_ETH } from './constants'
 
 /**
  * @param bglAddress is the address to receive BGL to
  * @param wbglAmount is the amount of WBGL tokens to swap for BGL amount
+ * @param sourceWBGLAddress is the address/account containing WBGL tokens to swap. 
+ * NOTE: should be address linked to the signer(wallet) to be able to sign messages authorizing the swap.
  */
 export interface WBGLBGLExchangePair {
   bglAddress: string
   to: string
-  recepientWbglAddress: string
+  sourceWBGLAddress?: string
   wbglAmount: number
 }
 
 export class WBGL {
   /**
    * @member web3 instance to use.
    */
-  private readonly web3: Web3
+  private readonly provider: ethers.providers.JsonRpcProvider | ethers.providers.Web3Provider
   /**
    * @member chainId The chainId of the network to use
    */
   private readonly chainId: number | string | ChaindIds
   private readonly chainName: string
   private readonly bridgeEndpoint = 'https://bglswap.com/app/'
+  private readonly evmPrivateKey: string
 
   constructor(config: IBridgeConfig) {
-    this.web3 = new Web3(config.provider)
+    this.provider = config.provider
     this.chainId = config.chainId
     this.chainName = config.chainName
+    this.evmPrivateKey = config.evmPrivateKey
   }
 
   /// START PUBLIC METHODS
@@ -40,15 +45,15 @@ export class WBGL {
    * @param from
    * swapWBGLforBGL swaps WBGL for BGL to recepient Bitgesell address
    */
-  public async swapWBGLforBGL({
+  public async swapWBGLtoBGL({
     bglAddress,
-    recepientWbglAddress,
-    wbglAmount
+    wbglAmount,
+    sourceWBGLAddress
   }: WBGLBGLExchangePair) {
     try {
-      const addressess = await this.web3.eth.getAccounts()
-      const account = recepientWbglAddress || addressess[0]
-      const signature = await this._signMessage(account, bglAddress)
+      const signer = await this._getSigner()
+      const account = sourceWBGLAddress || await signer.getAddress()
+      const signature = await this._signMessage(bglAddress)
 
       const headers = {
         'Content-Type': 'application/json',
@@ -61,11 +66,13 @@ export class WBGL {
         ethAddress: account,
         signature,
       }
+
       const res = await fetch(`${this.bridgeEndpoint}submit/wbgl`, {
         headers,
         body: JSON.stringify(dataObject),
         method: 'POST'
       })
+
       const bridgeResponse = await res.json()
 
       const { address: sendAddress } = bridgeResponse
@@ -78,38 +85,74 @@ export class WBGL {
   } /// END OF PUBLIC METHODS
 
   /// START PRIVATE METHODS
-  private async _signMessage(account: string, message: string) {
-    return await this.web3.eth.sign(message, account)
+  private async _signMessage(message: string) {
+    const signer = await this._getSigner()
+    const signedMessage = await signer.signMessage(message)
+    return signedMessage
   }
 
-  public async _sendWbgl(
+
+
+  private async _sendWbgl(
     from: string,
     to: string,
     amount: number
   ) {
-    const value = this.web3.utils.toWei(amount, 'ether')
-    const tokenAddress = await this._getWBGLTokenAddress()
-    // TODO: perform gas estimate to avoid exhorbitant gas fees
-    const WBGContractInstance = new this.web3.eth.Contract(abi, tokenAddress)
-    const tx = await WBGContractInstance.methods.transfer(to, value).send({ from })
-    return tx
-  }
-
-  private async _getWBGLTokenAddress(): Promise<string> {
     try {
-      const res = await fetch(`${this.bridgeEndpoint}/contracts`)
-      const contracts = await res.json() as IContracts
-      return contracts[this.isChainBsc(this.chainId) ? 'bsc' : 'eth']
+      const txData = {
+        to,
+        gasLimit: null,
+        nonce: null,
+        maxFeePerGas: null,
+        value: null, // 
+        maxPriorityFeePerGas: null
+      }
+
+      const value = ethers.utils.parseUnits(String(amount), 18)
+      const tokenAddress = this._getWBGLTokenAddress()
+      const signer = await this._getSigner()
+      const nonce = await signer.getTransactionCount()
+      const feeData = await signer.getFeeData()
+      const price = feeData.maxFeePerGas
+
+      // TODO: perform gas estimate to avoid exhorbitant gas fees
+      const WBGLContractInstance = new ethers.Contract(tokenAddress, WBGL_ABI)
+      const estimate = WBGLContractInstance.transfer.estimateGas(to, value)
+      const result = await estimate()
+
+      txData.value = value
+      txData.gasLimit = result
+      txData.nonce = nonce
+      txData.maxFeePerGas = price
+      txData.maxPriorityFeePerGas = price.div(10)
+
+      // const fee = price.mul(txData.gasLimit)
+
+      const tx = await WBGLContractInstance.methods.transfer(to, value).send({ from })
+      const request = await WBGLContractInstance.transfer(txData.to, txData.value, tx)
+      return request
+
     } catch (error) {
       return error
     }
   }
 
+  private _getWBGLTokenAddress(): string {
+    // @TODO: add Optimism and Arbitrum contract addresses
+    return this.isChainBsc(this.chainId) ? WBGL_CONTRACT_ADDRESS_BNB : WBGL_CONTRACT_ADDRESS_ETH
+  }
+
 
+  // @TODO: include Arbitrum, Optimism checks
   private isChainBsc(chainId: string | number): boolean {
     const bscChainIds: (string | number)[] = ['0x38', '0x61'] // Binance Smart Chain (Mainnet & Testnet) chain IDs
     return bscChainIds.includes(chainId)
-  }   /// END OF PRIVATE METHODS
+  }
+
+  private async _getSigner() {
+    if (this.evmPrivateKey) return new Wallet(this.evmPrivateKey, this.provider)
+    else return this.provider.getSigner() // Web3Provider injected by MetaMask web wallets
+  } /// END OF PRIVATE METHODS
 
 }