Binance 的跨链`Ethereum`智能合约

struct Swap {
    uint256 outAmount;
    uint256 expireHeight;
    bytes32 randomNumberHash;
    uint64  timestamp;
    address payable sender;
    address payable recipientAddr;
}

mapping (bytes32 => Swap) private swaps;
mapping (bytes32 => States) private swapStates;

- key: Swap-ID，上篇文章有描述swapStates: 合约中存储的原子交换的状态；依据不同的事件，更新原子交换的状态

- key: Swap-ID，上篇文章有描述

enum States {
        INVALID,
        OPEN,
        COMPLETED,
        EXPIRED
    }

function htlt(bytes32 _randomNumberHash, uint64  _timestamp, uint256 _heightSpan, address payable _recipientAddr,
bytes20 _bep2SenderAddr, bytes20 _bep2RecipientAddr, uint256 _bep2Amount) external payable returns (bool) {
    ...
    
    swaps[swapID] = swap;
    swapStates[swapID] = States.OPEN;
    emit HTLT(msg.sender, _recipientAddr, swapID, _randomNumberHash, _timestamp, _bep2RecipientAddr, swap.expireHeight, msg.value, _bep2Amount);
}
function claim(bytes32 _swapID, bytes32 _randomNumber) external onlyOpenSwaps(_swapID) onlyBeforeExpireHeight(_swapID) onlyWithRandomNumber(_swapID, _randomNumber) returns (bool) {
    swapStates[_swapID] = States.COMPLETED;
    ...
    recipientAddr.transfer(outAmount);
    emit Claimed(msg.sender, recipientAddr, _swapID, randomNumberHash, _randomNumber);
}
function refund(bytes32 _swapID) external onlyOpenSwaps(_swapID) onlyAfterExpireHeight(_swapID) returns (bool) {
    swapStates[_swapID] = States.EXPIRED;
    ...
    swapSender.transfer(outAmount);
    emit Refunded(msg.sender, swapSender, _swapID, randomNumberHash);
}