Settle Trade Payment

EVM-Compatible Networks

Authorized Settlement with Fee Deduction

function settlement(
    bytes32 tradeId,
    uint256 totalFee,
    address toAddress,
    TradeDetail calldata detail,
    bytes calldata presign,
    bytes calldata mpcSignature
) external nonReentrant;

🔐 Permissioned Execution

• Can only be executed by authorized actors capable of producing valid mpcSignature and presign.

• Ensures that settlement is authorized through off-chain coordination and validation.

🔎 Trade Validation

• Callable only if block.timestamp <= detail.timeout.

• Prevents settlement after the trade has expired.

• Validates that the provided TradeDetail matches the recorded hash for the tradeId.

• Guards against tampering and unauthorized settlements.

🔑 Signature Verification

• Verifies a pre-signature from the ephemeral asset signer.

• Confirms the settlement recipient (toAddress) and authorized amount.

• Requires a valid signature from the MPC to authorize settlement.

• Ensures consensus among off-chain nodes has been reached before finalizing the trade.

💰 Protocol Fee Handling

• If totalFee is non-zero, the specified amount is transferred to protocol.pFeeAddr() before proceeding with settlement.

• Guarantees protocol fee collection before fund distribution.

💸 Transfer Execution

• Transfers the remaining amount (amount - totalFee) to the PMM’s designated receiving address (toAddress).

📢 Event Emission

• Emits a Settled event containing all relevant data: tradeId, fee recipient, final recipient, total fee, and transferred amount.

Bitcoin Network

Unlike EVM and Solana networks which use smart contracts, Bitcoin utilizes the Native Bitcoin Vault—a non-custodial escrow built with Bitcoin's native scripting.

Users deposit BTC into a P2TR (Pay-to-Taproot) address controlled by a 2-of-2 multisig between the user and the Settlement Committee. Trades are settled when both parties sign, or users can reclaim funds after timelock expiry using only their own key.

For technical details on vault construction, spending paths, and security model, see Native Bitcoin Vault.

Solana Networks

Authorized Settlement with Fee Deduction

pub struct SettlementArgs {
    /// The tradeId, unique identifier for the trade
    pub trade_id: [u8; 32], // uint256
}
pub fn handler_settlement<'c: 'info, 'info>(
    ctx: Context<'_, '_, 'c, 'info, SettlementAccounts<'info>>,
    settlement_args: SettlementArgs,
) -> Result<()>                                                                                        

🔐 Permissioned Execution

• Can only be executed by authorized actors capable of producing valid mpcSignature and ephemeralSignature.

• Ensures that settlement is authorized through off-chain coordination and validation.

🔎 Trade Validation

• Callable only if Clock::get().unix_timestamp <= trade_detail.timeout.

• Can only be executed for the TradeDatail in the Deposited state.

• Prevents settlement after the trade has expired.

• Validates that the provided TradeDetail matches the recorded hash for the tradeId.

• Guards against tampering and unauthorized settlements.

🔑 Signature Verification

• Verifies a signature from the ephemeral asset signer.

• Confirms the settlement recipient (toAddress) and authorized amount.

• Requires a valid signature from the MPC to authorize settlement.

• Ensures consensus among off-chain nodes has been reached before finalizing the trade.

💰 Protocol Fee Handling

• If totalFee is non-zero, the specified amount is transferred to protocol account before proceeding with settlement.

• Guarantees protocol fee collection before fund distribution.

💸 Transfer Execution

• Transfers the remaining amount (amount - totalFee) to the PMM’s designated receiving address (toAddress).

• Update the status of corresponding TradeDetail account from Deposited to Settled

📌 Note: This function represents the final stage of a successful trade. It finalizes the transfer of funds according to MPC authorization and ensures both the PMM and protocol receive their respective payments securely.