set up base + dev notes

contracts/test/TestUniV3Contract.sol

@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+
+import '@uniswap/v3-periphery/contracts/interfaces/ISwapRouter.sol';
+
+contract UniV3Integration {
+  ISwapRouter router;
+
+  function doSomethingWithSwapRouter() public {
+    // router.exactInput(...);
+  }
+}

contracts/token/BiconomyTokenPaymaster.sol

@@ -69,6 +69,9 @@ contract BiconomyTokenPaymaster is BasePaymaster, ReentrancyGuard, TokenPaymaste
     // Owned contract that manages chainlink price feeds (token / eth formaat) and helper to give exchange rate (inverse price)
     IOracleAggregator public oracleAggregator;
 
+    // todo: possibly add interface later
+    address public swapAdapter1; // named 1 for now
+
     /**
      * Designed to enable the community to track change in storage variable UNACCOUNTED_COST which is used
      * to maintain gas execution cost which can't be calculated within contract*/
@@ -125,9 +128,10 @@ contract BiconomyTokenPaymaster is BasePaymaster, ReentrancyGuard, TokenPaymaste
         address _owner,
         IEntryPoint _entryPoint,
         address _verifyingSigner,
-        IOracleAggregator _oracleAggregator
-        // potentially take router param as well
-        // optionally get fee receiver if we need to (can always set after deploying!)
+        IOracleAggregator _oracleAggregator, 
+        address _1inchAggregationRouter 
+        // ^ let's pick 1inch here for swapping on eligible chains
+        //  0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE // by default unsupported
     ) payable BasePaymaster(_owner, _entryPoint) {
         if(_owner == address(0)) revert OwnerCannotBeZero();
         if (address(_entryPoint) == address(0)) revert EntryPointCannotBeZero();
@@ -137,9 +141,15 @@ contract BiconomyTokenPaymaster is BasePaymaster, ReentrancyGuard, TokenPaymaste
             sstore(verifyingSigner.slot, _verifyingSigner)
             sstore(oracleAggregator.slot, _oracleAggregator)
             sstore(feeReceiver.slot, address())  // initialize with self (could also be _owner)
+            sstore(swapAdapter1.slot, _1inchAggregationRouter) // valid only if supported
         }
     }
 
+    // if needful
+    function set1InchAdapter(address _newVerifyingSigner) external payable onlyOwner {
+
+    }
+
     /**
      * @dev Set a new verifying signer address.
      * Can only be called by the owner of the contract.
@@ -258,6 +268,7 @@ contract BiconomyTokenPaymaster is BasePaymaster, ReentrancyGuard, TokenPaymaste
         address _token
     ) public view virtual returns (uint256 exchangeRate) {
         // get price from oracle aggregator.
+        // todo: from adapter TWAP oracle POV this would need more than token address, like price source
         bytes memory _data = abi.encodeWithSelector(IOracleAggregator.getTokenValueOfOneEth.selector, _token);
         (bool success, bytes memory returndata) = address(oracleAggregator).staticcall(_data);
         exchangeRate = 0;
@@ -266,6 +277,14 @@ contract BiconomyTokenPaymaster is BasePaymaster, ReentrancyGuard, TokenPaymaste
         }
     }
 
+    // returns success and possibly amount and emits event
+    function swapTokenForETHAndDeposit(address _token, bytes memory _calldata) public /*returns*/{
+        // only proceed if adapter is not '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE'
+        // make approval to router 
+        // 1InchAdapter.call(calldata)..
+        // entrypoint.depositTo
+    }
+
     /**
      * @dev pull tokens out of paymaster in case they were sent to the paymaster at any point.
      * @param token the token deposit to withdraw

contracts/token/adapters/UniswapExample.sol

@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.17;
+pragma abicoder v2;
+
+import "@uniswap/v3-periphery/contracts/interfaces/ISwapRouter.sol";
+import "@uniswap/v3-periphery/contracts/interfaces/IQuoter.sol";
+
+interface IUniswapRouter is ISwapRouter {
+    function refundETH() external payable;
+}
+
+contract Uniswap3 {
+  IUniswapRouter public constant uniswapRouter = IUniswapRouter(0xE592427A0AEce92De3Edee1F18E0157C05861564);
+  IQuoter public constant quoter = IQuoter(0xb27308f9F90D607463bb33eA1BeBb41C27CE5AB6);
+  address private constant multiDaiKovan = 0x4F96Fe3b7A6Cf9725f59d353F723c1bDb64CA6Aa;
+  address private constant WETH9 = 0xd0A1E359811322d97991E03f863a0C30C2cF029C;
+
+  function convertExactEthToDai() external payable {
+    require(msg.value > 0, "Must pass non 0 ETH amount");
+
+    uint256 deadline = block.timestamp + 15; // using 'now' for convenience, for mainnet pass deadline from frontend!
+    address tokenIn = WETH9;
+    address tokenOut = multiDaiKovan;
+    uint24 fee = 3000;
+    address recipient = msg.sender;
+    uint256 amountIn = msg.value;
+    uint256 amountOutMinimum = 1;
+    uint160 sqrtPriceLimitX96 = 0;
+
+    ISwapRouter.ExactInputSingleParams memory params = ISwapRouter.ExactInputSingleParams(
+        tokenIn,
+        tokenOut,
+        fee,
+        recipient,
+        deadline,
+        amountIn,
+        amountOutMinimum,
+        sqrtPriceLimitX96
+    );
+
+    uniswapRouter.exactInputSingle{ value: msg.value }(params);
+    uniswapRouter.refundETH();
+
+    // refund leftover ETH to user
+    (bool success,) = msg.sender.call{ value: address(this).balance }("");
+    require(success, "refund failed");
+  }
+
+  function convertEthToExactDai(uint256 daiAmount) external payable {
+    require(daiAmount > 0, "Must pass non 0 DAI amount");
+    require(msg.value > 0, "Must pass non 0 ETH amount");
+
+    uint256 deadline = block.timestamp + 15; // using 'now' for convenience, for mainnet pass deadline from frontend!
+    address tokenIn = WETH9;
+    address tokenOut = multiDaiKovan;
+    uint24 fee = 3000;
+    address recipient = msg.sender;
+    uint256 amountOut = daiAmount;
+    uint256 amountInMaximum = msg.value;
+    uint160 sqrtPriceLimitX96 = 0;
+
+    ISwapRouter.ExactOutputSingleParams memory params = ISwapRouter.ExactOutputSingleParams(
+        tokenIn,
+        tokenOut,
+        fee,
+        recipient,
+        deadline,
+        amountOut,
+        amountInMaximum,
+        sqrtPriceLimitX96
+    );
+
+    uniswapRouter.exactOutputSingle{ value: msg.value }(params);
+    uniswapRouter.refundETH();
+
+    // refund leftover ETH to user
+    (bool success,) = msg.sender.call{ value: address(this).balance }("");
+    require(success, "refund failed");
+  }
+
+  // do not used on-chain, gas inefficient!
+  function getEstimatedETHforDAI(uint daiAmount) external payable returns (uint256) {
+    address tokenIn = WETH9;
+    address tokenOut = multiDaiKovan;
+    uint24 fee = 3000;
+    uint160 sqrtPriceLimitX96 = 0;
+
+    return quoter.quoteExactOutputSingle(
+        tokenIn,
+        tokenOut,
+        fee,
+        daiAmount,
+        sqrtPriceLimitX96
+    );
+  }
+
+  // important to receive ETH
+  receive() payable external {}
+}

package.json

@@ -47,9 +47,13 @@
     "@chainlink/contracts": "^0.6.0",
     "@ethersproject/abstract-signer": "^5.6.2",
     "@ethersproject/constants": "^5.6.1",
+    "@mean-finance/uniswap-v3-oracle": "^1.0.3",
     "@openzeppelin/contracts": "4.8.1",
     "@openzeppelin/contracts-upgradeable": "4.8.1",
     "@types/mocha": "^9.0.0",
+    "@uniswap/sdk-core": "^3.2.2",
+    "@uniswap/universal-router": "^1.4.1",
+    "@uniswap/v3-periphery": "^1.4.3",
     "chai-as-promised": "^7.1.1",
     "chai-string": "^1.5.0",
     "dotenv": "^16.0.3",

scripts/deploy-token-paymaster-mumbai.ts

@@ -5,6 +5,7 @@ async function main() {
   const provider = ethers.provider;
 
   const accounts = await ethers.getSigners();
+  const ZERO_ADDRESS_ROUTER = '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE'
 
   const earlyOwner = await accounts[0].getAddress();
   const owner = "0x7306aC7A32eb690232De81a9FFB44Bb346026faB";
@@ -31,7 +32,8 @@ async function main() {
     earlyOwner,
     entryPoint,
     verifyingSigner,
-    oracleAggregator.address
+    oracleAggregator.address,
+    ZERO_ADDRESS_ROUTER
   );
 
   console.log(`TokenPaymaster deployed at ${tokenPaymaster.address}`);

scripts/deploy-token-paymaster-polygon-mainnet.ts

@@ -13,6 +13,7 @@ async function main() {
   const provider = ethers.provider;
 
   const gasPrices = {maxFeePerGas: 250e9, maxPriorityFeePerGas: 60e9}
+  const ZERO_ADDRESS_ROUTER = '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE'
 
   const accounts = await ethers.getSigners();
   const earlyOwner = await accounts[0].getAddress();
@@ -41,7 +42,8 @@ async function main() {
     earlyOwner,
     entryPoint,
     verifyingSigner,
-    oracleAggregator.address
+    oracleAggregator.address,
+    ZERO_ADDRESS_ROUTER
   );
 
   await delay(5000)

test/token-paymaster/biconomy-token-paymaster-specs.ts

@@ -19,6 +19,8 @@ import {
   MockToken,
 } from "../../typechain-types";
 
+const ZERO_ADDRESS_ROUTER = '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE'
+
 
 import { fillAndSign } from "../../account-abstraction/test/UserOp";
 import { UserOperation } from "../../account-abstraction/test/UserOperation";
@@ -150,7 +152,8 @@ describe("Biconomy Token Paymaster", function () {
       walletOwnerAddress,
       entryPoint.address,
       await offchainSigner.getAddress(),
-      oracleAggregator.address
+      oracleAggregator.address,
+      ZERO_ADDRESS_ROUTER
     );
 
     await sampleTokenPaymaster.setTokenAllowed(token.address, true);

test/token-paymaster/btpm-undeployed-wallet.ts

@@ -26,6 +26,7 @@ import { createAccount, simulationResultCatch } from "../../account-abstraction/
 import { EntryPoint, EntryPoint__factory, SimpleAccount, TestToken, TestToken__factory } from "../../account-abstraction/typechain";
 
 export const AddressZero = ethers.constants.AddressZero;
+const ZERO_ADDRESS_ROUTER = '0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE'
 import { arrayify, hexConcat, parseEther } from "ethers/lib/utils";
 import { BigNumber, BigNumberish, Contract, Signer } from "ethers";
 
@@ -150,7 +151,8 @@ describe("Biconomy Token Paymaster", function () {
       walletOwnerAddress,
       entryPoint.address,
       await offchainSigner.getAddress(),
-      oracleAggregator.address
+      oracleAggregator.address,
+      ZERO_ADDRESS_ROUTER
     );
 
     await sampleTokenPaymaster.setTokenAllowed(token.address, true);