Contract

// SPDX-License-Identifier: MIT
pragma solidity 0.8.21;

interface IFluidWalletFactory {
    function walletImplementation() external returns(address);
}

/// @title      FluidWallet
/// @notice     Proxy for Fluid wallet as deployed by the FluidWalletFactory.
///             Basic Proxy with fallback to delegate and address for implementation contract at storage 0x0
//
contract FluidWallet {
    /// @notice Fluid Wallet Factory address.
    IFluidWalletFactory public immutable FACTORY;

    /// @notice Owner of the wallet.
    address public owner;

    function initialize(address owner_) public {
        if (owner == address(0)) {
            owner = owner_;
        } else {
            revert();
        }
    }

    constructor (address factory_) {
        FACTORY = IFluidWalletFactory(factory_);
    }

    receive() external payable {}

    fallback() external payable {
        address impl_ = FACTORY.walletImplementation();
        assembly {
            // @dev code below is taken from OpenZeppelin Proxy.sol _delegate function

            // Copy msg.data. We take full control of memory in this inline assembly
            // block because it will not return to Solidity code. We overwrite the
            // Solidity scratch pad at memory position 0.
            calldatacopy(0, 0, calldatasize())

            // Call the implementation.
            // out and outsize are 0 because we don't know the size yet.
            let result := delegatecall(gas(), impl_, 0, calldatasize(), 0, 0)

            // Copy the returned data.
            returndatacopy(0, 0, returndatasize())

            switch result
            // delegatecall returns 0 on error.
            case 0 {
                revert(0, returndatasize())
            }
            default {
                return(0, returndatasize())
            }
        }
    }
}

{
  "remappings": [
    "forge-std/=lib/forge-std/src/",
    "erc4626-tests/=lib/erc4626-tests/",
    "solmate/=lib/solmate/",
    "openzeppelin-contracts/=lib/openzeppelin-contracts/src/",
    "openzeppelin-contracts-upgradeable/=lib/openzeppelin-contracts-upgradeable/src/",
    "@openzeppelin/=node_modules/@openzeppelin/",
    "ds-test/=lib/forge-std/lib/ds-test/src/",
    "eth-gas-reporter/=node_modules/eth-gas-reporter/",
    "hardhat-deploy/=node_modules/hardhat-deploy/",
    "hardhat/=node_modules/hardhat/"
  ],
  "optimizer": {
    "enabled": true,
    "runs": 10000000
  },
  "metadata": {
    "useLiteralContent": false,
    "bytecodeHash": "ipfs",
    "appendCBOR": true
  },
  "outputSelection": {
    "*": {
      "*": [
        "evm.bytecode",
        "evm.deployedBytecode",
        "devdoc",
        "userdoc",
        "metadata",
        "abi"
      ]
    }
  },
  "evmVersion": "paris",
  "libraries": {}
}

[{"inputs":[{"internalType":"address","name":"factory_","type":"address"}],"stateMutability":"nonpayable","type":"constructor"},{"stateMutability":"payable","type":"fallback"},{"inputs":[],"name":"FACTORY","outputs":[{"internalType":"contract IFluidWalletFactory","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"inputs":[{"internalType":"address","name":"owner_","type":"address"}],"name":"initialize","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[],"name":"owner","outputs":[{"internalType":"address","name":"","type":"address"}],"stateMutability":"view","type":"function"},{"stateMutability":"payable","type":"receive"}]