add upgradeability pattern to project

Author: eduv09

PLAN.md

@@ -19,188 +19,24 @@
  *   along with confidential-token.  If not, see <https://www.gnu.org/licenses/>.
  */
 
-// cspell:words IERC20
-
 pragma solidity ^0.8.27;
 
-import { ERC20, IERC20 }  from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-import { ERC20Wrapper }   from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Wrapper.sol";
 import { IERC20Metadata } from "@openzeppelin/contracts/token/ERC20/extensions/IERC20Metadata.sol";
-import { SafeERC20 }      from "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
-import { Math }           from "@openzeppelin/contracts/utils/math/Math.sol";
 
-import { BITE, ConfidentialToken }    from "./ConfidentialToken.sol";
-import { IConfidentialWrapper } from "./interfaces/IConfidentialWrapper.sol";
+import { ConfidentialWrapperCore } from "./core/ConfidentialWrapperCore.sol";
 
 
 /// @title ConfidentialWrapper
 /// @author Dmytro Stebaiev
 /// @notice Confidential wrapper that adds confidentiality to an ERC20 token
-contract ConfidentialWrapper is ConfidentialToken, ERC20Wrapper, IConfidentialWrapper {
-    using SafeERC20 for IERC20;
-
-    uint8 private constant _WITHDRAW_TO_ACTION = 2;
-
-
-    /// @notice Amount of tokens requested to be wrapped
-    /// @dev Almost always equals to zero
-    /// @dev Has non-zero value only before the callback call is made
-    mapping (address holder => uint256 value) public requestedMints;
-
-    error OutdatedMint(address to, uint256 value);
-    error ZeroValue();
-
+contract ConfidentialWrapper is ConfidentialWrapperCore {
     constructor(
         IERC20Metadata underlyingToken,
         string memory version_,
         address initialAuthority
     )
-        ConfidentialToken(
-            string.concat("Confidential ", underlyingToken.name()),
-            string.concat("cnf", underlyingToken.symbol()),
-            version_,
-            initialAuthority
-        )
-        ERC20Wrapper(underlyingToken)
-    {}
-
-    // External functions
-
-    /// @inheritdoc IConfidentialWrapper
-    function releaseTo(address account, uint256 value) external override {
-        requestedMints[_msgSender()] -= value;
-        underlying().safeTransfer(account, value);
-    }
-
-    // Public functions
-
-    ///@inheritdoc ConfidentialToken
-    function transferFrom(
-        address from,
-        address to,
-        uint256 value
-    ) public virtual override(ConfidentialToken, ERC20) returns (bool result) {
-        return ConfidentialToken.transferFrom(from, to, value);
-    }
-
-    /// @inheritdoc ERC20Wrapper
-    /// @dev Pending mint accounting is keyed by the recipient `account`, so only
-    /// `account` can later call `releaseTo` for this deposit.
-    function depositFor(address account, uint256 value) public override returns (bool success) {
-        requestedMints[account] += value;
-        return super.depositFor(account, value);
-    }
-
-    /// @inheritdoc ERC20Wrapper
-    /// @dev This operation is asynchronous and finalizes in the callback. On
-    /// success, underlying tokens are sent to `account`.
-    function withdrawTo(address account, uint256 value) public override returns (bool success) {
-        _burnTo(_msgSender(), account, value);
-        return true;
-    }
-
-    /// @inheritdoc ERC20Wrapper
-    function decimals() public view override(ERC20, ERC20Wrapper) returns (uint8 decimalsValue) {
-        return ERC20Wrapper.decimals();
-    }
-
-    /// @inheritdoc ConfidentialToken
-    function totalSupply() public view override(ConfidentialToken, ERC20) returns (uint256 supply) {
-        return ConfidentialToken.totalSupply();
-    }
-
-    /// @inheritdoc ConfidentialToken
-    function balanceOf(address account) public pure override(ConfidentialToken, ERC20) returns (uint256 balance) {
-        return ConfidentialToken.balanceOf(account);
-    }
-
-    // Internal functions
-
-    /// @notice Dispatches decrypted CTX actions for wrapper-specific flows.
-    /// @dev Handles `_WITHDRAW_TO_ACTION` locally and delegates all other actions to
-    /// the base ConfidentialToken logic.
-    /// @param action Action discriminator encoded in callback plaintext.
-    /// @param decryptedArguments Decrypted callback arguments from BITE.
-    /// @param plaintextArguments Plaintext callback arguments used for routing.
-    function _handleAction(
-        uint8 action,
-        bytes[] calldata decryptedArguments,
-        bytes[] calldata plaintextArguments
-    ) internal override {
-        if (action == _WITHDRAW_TO_ACTION) {
-            _handleWithdrawToRequest(decryptedArguments, plaintextArguments);
-            return;
-        }
-        super._handleAction(action, decryptedArguments, plaintextArguments);
-    }
-
-    /// @notice Schedules an async burn that releases underlying to `to` on callback.
-    /// @dev Encodes `to` as extra plaintext callback data for
-    /// `_handleWithdrawToRequest`.
-    /// @param from Address whose confidential balance is debited.
-    /// @param to Recipient of the released underlying token.
-    /// @param value Amount to burn and unwrap.
-    function _burnTo(address from, address to, uint256 value) internal {
-        if (to == address(0) || to == address(this)) {
-            revert ERC20InvalidReceiver(to);
-        }
-        require(value != 0, ZeroValue());
-        bytes memory encryptedValue = BITE.encryptTE(encryptTEAddress, abi.encodePacked(value));
-        bytes[] memory extraArgs = new bytes[](1);
-        extraArgs[0] = abi.encodePacked(to);
-        _encryptedUpdateExtended({
-            from: from,
-            to: address(0),
-            spender: address(0),
-            gasPayer: _msgSender(),
-            encryptedValue: encryptedValue,
-            action: _WITHDRAW_TO_ACTION,
-            extraPlaintextArguments: extraArgs
-        });
-    }
-
-    function _onUpdate(address from, address to, uint256 value) internal override {
-        ConfidentialToken._onUpdate(from, to, value);
-        if (from == address(0)) {
-            _onMint(to, value);
-        }
-    }
-
-    function _update(address from, address to, uint256 value) internal override(ConfidentialToken, ERC20) {
-        ConfidentialToken._update(from, to, value);
-    }
-
-    // Private functions
-
-    function _onMint(address to, uint256 value) private {
-        bool previouslyRequested;
-        (previouslyRequested, requestedMints[to]) = Math.trySub(
-            requestedMints[to],
-            value
-        );
-        require(previouslyRequested, OutdatedMint(to, value));
-    }
-
-    /// @notice Finalizes a queued wrapper burn/withdraw callback.
-    /// @dev Validates recipient plaintext argument, finalizes encrypted transfer
-    /// accounting via `_handleTransferRequest`, then releases underlying.
-    /// @param decryptedArguments Decrypted callback arguments from BITE.
-    /// @param plaintextArguments Plaintext callback arguments containing recipient.
-    function _handleWithdrawToRequest(
-        bytes[] calldata decryptedArguments,
-        bytes[] calldata plaintextArguments
-    )
-        private
+        initializer
     {
-        require(plaintextArguments.length > 2, WrongPlaintextFormat());
-        require(plaintextArguments[2].length == 20, WrongPlaintextFormat());
-
-        (bool finalized, uint256 value) = _handleTransferRequest(decryptedArguments, plaintextArguments);
-        if (!finalized) {
-            return;
-        }
-
-        address recipient = address(bytes20(plaintextArguments[2]));
-        underlying().safeTransfer(recipient, value);
+        __ConfidentialWrapper_init(underlyingToken, version_, initialAuthority);
     }
 }

contracts/ConfidentialToken.sol

@@ -21,14 +21,13 @@
 
 pragma solidity ^0.8.27;
 
-import { ConfidentialToken } from "./ConfidentialToken.sol";
-import { IMintableERC20 } from "./interfaces/IMintableERC20.sol";
+import { MintableConfidentialTokenCore } from "./core/MintableConfidentialTokenCore.sol";
 
 
 /// @title MintableConfidentialToken
 /// @author Dmytro Stebaiev
 /// @notice ConfidentialToken with minting functionality
-contract MintableConfidentialToken is ConfidentialToken, IMintableERC20 {
+contract MintableConfidentialToken is MintableConfidentialTokenCore {
     /// @notice Constructor of the MintableConfidentialToken contract
     /// @param name Name of the token
     /// @param symbol Symbol of the token
@@ -40,16 +39,8 @@ contract MintableConfidentialToken is ConfidentialToken, IMintableERC20 {
         string memory version_,
         address initialAuthority
     )
-        ConfidentialToken(name, symbol, version_, initialAuthority)
-    {}
-
-    /// @inheritdoc IMintableERC20
-    function mint(address to, uint256 amount) external override restricted {
-        _mint(to, amount);
-    }
-
-    /// @inheritdoc IMintableERC20
-    function burn(uint256 amount) external override {
-        _burn(_msgSender(), amount);
+        initializer
+    {
+        __MintableConfidentialToken_init(name, symbol, version_, initialAuthority);
     }
 }