[FEATURE]: WEEK 2

[aniket866]

Feature and its Use Cases

Issue Summary Table

ID	Issue Name	Description	Target Files	Complexity	Priority
** 01**	Batch Order Matching	Allow keepers to match one large order against multiple smaller counter-orders in a single transaction to save gas.	WindmillExchange.sol IWindmillExchange.sol	Medium	High
** 02**	Native ETH Integration	Support native ETH trading by wrapping deposited ETH into WETH and unwrapping WETH to ETH on withdrawal or settlement.	WindmillExchange.sol IWindmillExchange.sol	High	High
** 03**	Protocol Fees	Introduce a customizable protocol fee collected to a treasury address, separate from the keeper execution incentive fee.	WindmillExchange.sol IWindmillExchange.sol	Medium	Medium
** 04**	Access & Pausing Safety	Restructure permissioned actions, remove pausing constraints on cancellations, and implement safety caps on admin configurations.	WindmillExchange.sol	Low	Medium

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Technical Specifications

01: Batch Order Matching

• Objective: Save gas and allow keepers to clear liquidity efficiently by matching a single primary order (either buy or sell) against an array of opposing counter-orders.
• Implementation Plan:
  • Implement matchBatch(uint256 primaryOrderId, uint256[] calldata counterOrderIds, uint256 deadline).
  • Optimize storage writes by reading and updating the primary order once (or writing the updated state at the end of the loop).

02: Native ETH Integration

• Objective: Native ETH deposits automatically wrap to WETH, and WETH unwraps back to native ETH on cancels or settlements.
• Implementation Plan:
  • Represent native ETH using address(0).
  • Accept msg.value in createOrder when tokenIn == address(0). Wrap ETH using WETH.deposit{value: msg.value}().
  • During cancelOrder, if tokenIn == address(0), call WETH.withdraw(refund) and transfer native ETH back to the maker.
  • During matches, if the receiver expects address(0) as the output token, unwrap WETH and send native ETH instead of WETH.
  • Add receive() external payable {} to accept native ETH from the WETH contract.

03: Protocol Fees

04: Access & Pausing Safety

• Objective: Guard against locked user funds and access control vulnerabilities.
• Implementation Plan:
  • Remove whenNotPaused modifier from cancelOrder to ensure users can withdraw/cancel orders at any time.
  • Ensure all updates to treasury and fees emit explicit tracking events.
  • Validate inputs for all new admin settings (non-zero treasury address, fee ceilings).

Additional Context

N/A

Code of Conduct

• I have joined the Discord server and will post updates there
• I have searched existing issues to avoid duplicates