feat: Add basic setup code for Diamond Hook

foundry.toml

@@ -2,5 +2,11 @@
 src = "src"
 out = "out"
 libs = ["lib"]
+solc_version = '0.8.20'
+evm_version = "paris"
+
+[profile.ci]
+fuzz_runs = 100000
+solc = "./lib/v4-core/bin/solc-static-linux"
 
 # See more config options https://github.com/foundry-rs/foundry/blob/master/crates/config/README.md#all-options

src/BaseFactory.sol

@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.20;
+
+import {IPoolManager} from "@uniswap/v4-core/src/interfaces/IPoolManager.sol";
+import {Hooks} from "@uniswap/v4-core/src/libraries/Hooks.sol";
+
+abstract contract BaseFactory {
+    /// @notice zero out all but the first byte of the address which is all 1's
+    uint160 public constant UNISWAP_FLAG_MASK = 0xff << 152;
+
+    // Uniswap hook contracts must have specific flags encoded in the first byte of their address
+    address public immutable TargetPrefix;
+
+    constructor(address _targetPrefix) {
+        TargetPrefix = _targetPrefix;
+    }
+
+    function deploy(IPoolManager poolManager, bytes32 salt) public virtual returns (address);
+
+    function mineDeploy(IPoolManager poolManager) external returns (address) {
+        return deploy(poolManager, 0);
+    }
+
+    function _computeHookAddress(IPoolManager poolManager, bytes32 salt) internal view returns (address) {
+        bytes32 hash = keccak256(abi.encodePacked(bytes1(0xff), address(this), salt, _hashBytecode(poolManager)));
+        return address(uint160(uint256(hash)));
+    }
+
+    /// @dev The implementing contract must override this function to return the bytecode hash of its contract
+    /// For example, the CounterHook contract would return:
+    /// bytecodeHash = keccak256(abi.encodePacked(type(CounterHook).creationCode, abi.encode(poolManager)));
+    function _hashBytecode(IPoolManager poolManager) internal pure virtual returns (bytes32 bytecodeHash);
+
+    function _isPrefix(address _address) internal view returns (bool) {
+        // zero out all but the first byte of the address
+        address actualPrefix = address(uint160(_address) & UNISWAP_FLAG_MASK);
+        return actualPrefix == TargetPrefix;
+    }
+}