server.js

function resetGame(game) {
    return {
        addressPlayer1: game.addressPlayer1,
        addressPlayer2: game.addressPlayer2,
        balancePlayer1: game.balancePlayer1,
        balancePlayer2: game.balancePlayer2,
        socketPlayer1: game.socketPlayer1,
        socketPlayer2: game.socketPlayer2
    }
}

// Checks that the message given by the player is valid to continue playing and to reveal the results
function verifyMessage(signedMessage, nonce, call, bet, balance, sequence, playerAddress) {
	const hash = generateHash(nonce, call, bet, balance, sequence)
	const message = ethereumjs.soliditySHA3(
		['string', 'bytes32'],
		['\x19Ethereum Signed Message:\n32', hash]
	)
	const splitSignature = ethereumjsUtil.fromRpcSig(signedMessage)
	const publicKey = ethereumjsUtil.ecrecover(message, splitSignature.v, splitSignature.r, splitSignature.s)
	const signer = ethereumjsUtil.pubToAddress(publicKey).toString('hex')
	const isMessageValid = (signer.toLowerCase() == ethereumjsUtil.stripHexPrefix(playerAddress).toLowerCase())
	return isMessageValid
}

function generateHash(nonce, call, bet, balance, sequence) {
	const hash = '0x' + ethereumjs.soliditySHA3(
		['uint256', 'uint256', 'uint256', 'uint256', 'uint256'],
		[String(nonce), String(call), String(bet), String(balance), String(sequence)]
	).toString('hex')

	return hash
}