static void ExpectSuccess(LedgerOperationStatus status)
{
if (status != LedgerOperationStatus.Success)
{
throw new Exception("Operation failed with status " + status + ", expected Success");
}
}
LedgerOperationStatus ILedger.RemoveFunds(AccountID accountID, decimal balance)
{
LedgerOperationStatus status = LedgerOperationStatus.Success;
TransactionLine transaction = new TransactionLine(accountID,
balance,
LedgerDatabase.TransactionType.RemoveFunds);
//find account line, lock it, update
if (accountsTable.Contains(accountID))
{
AccountLine account = accountsTable.Select(accountID);
lock (account)
{
if (balance > account.Balance)
{
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InsufficientFunds;
status = LedgerOperationStatus.InsufficientFunds;
}
else
{
account.Balance -= balance;
}
}
}
else
{
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InvalidAccount;
status = LedgerOperationStatus.InvalidAccount;
}
transactionsTable.Insert(transaction);
return(status);
}
LedgerOperationStatus ILedger.TransferFunds(AccountID srcAccountID, AccountID tgtAccountID, decimal balance)
{
LedgerOperationStatus status = LedgerOperationStatus.Success;
TransactionLine srcTrans = new TransactionLine(srcAccountID,
balance,
LedgerDatabase.TransactionType.RemoveFunds, TransactionSubType.TransferFunds);
TransactionLine tgtTrans = new TransactionLine(tgtAccountID,
balance,
LedgerDatabase.TransactionType.AddFunds, TransactionSubType.TransferFunds);
lock (transactionsTable)
{
srcTrans.TransferId = tgtTrans.TransferId = ++transferID;
}
if (accountsTable.Contains(srcAccountID) && accountsTable.Contains(tgtAccountID))
{
AccountLine accSrc = accountsTable.Select(srcAccountID);
AccountLine accTgt = accountsTable.Select(tgtAccountID);
AccountLine firstAccToLock = accSrc, secondAccToLock = accTgt;
if (srcAccountID > tgtAccountID) // avoid deadlocks by always locking at the same order
{
firstAccToLock = accTgt;
secondAccToLock = accSrc;
}
lock (firstAccToLock)
{
lock (secondAccToLock)
{
if (balance > accSrc.Balance)
{
srcTrans.Status = tgtTrans.Status = LedgerDatabase.TransactionStatus.Rejected;
srcTrans.RejectReason = tgtTrans.RejectReason = TransactionRejectReason.InsufficientFunds;
status = LedgerOperationStatus.InsufficientFunds;
}
else
{
accSrc.Balance -= balance;
accTgt.Balance += balance;
}
}
}
}
else
{
srcTrans.Status = tgtTrans.Status = LedgerDatabase.TransactionStatus.Rejected;
srcTrans.RejectReason = tgtTrans.RejectReason = TransactionRejectReason.InvalidAccount;
status = LedgerOperationStatus.InvalidAccount;
}
transactionsTable.Insert(srcTrans);
transactionsTable.Insert(tgtTrans);
return(status);
}
LedgerOperationStatus ILedger.UnfreezeFunds(AccountID accountID, out decimal balance, UInt64 freezeID)
{
LedgerOperationStatus status = LedgerOperationStatus.Success;
//prepare AddFunds/Unfreeze transaction
TransactionLine transaction = new TransactionLine(accountID,
0,
LedgerDatabase.TransactionType.AddFunds, TransactionSubType.Unfreeze);
if (accountsTable.Contains(accountID))
{
AccountLine account = accountsTable.Select(accountID);
lock (account)
{
if (frozenBalancesTable.Contains(freezeID))
{
FrozenBalanceLine frozenBalance = frozenBalancesTable.Select(freezeID);
balance = frozenBalance.Balance;
if (frozenBalance.AccountId != accountID)
{
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InvalidAccount;
status = LedgerOperationStatus.InvalidAccount;
}
else
{
//update account balance and delete freeze record
account.Balance += frozenBalance.Balance;
frozenBalancesTable.Delete(freezeID);
}
}
else
{
balance = 0;
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InvalidFreezeID;
status = LedgerOperationStatus.InvalidFreezeID;
}
}
}
else
{
balance = 0;
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InvalidAccount;
status = LedgerOperationStatus.InvalidAccount;
}
transactionsTable.Insert(transaction);
return(status);
}
LedgerOperationStatus ILedger.GetAccountBalance(AccountID accountID, out decimal balance)
{
LedgerOperationStatus status = LedgerOperationStatus.Success;
if (accountsTable.Contains(accountID))
{
AccountLine account = accountsTable.Select(accountID);
lock (account)
{
balance = account.Balance;
}
}
else
{
balance = 0;
status = LedgerOperationStatus.InvalidAccount;
}
return(status);
}
LedgerOperationStatus ILedger.FreezeFunds(AccountID accountID, decimal balance, out FreezeID freezeID)
{
LedgerOperationStatus status = LedgerOperationStatus.Success;
//prepare RemoveFunds/Freeze transaction
TransactionLine transaction = new TransactionLine(accountID,
balance,
LedgerDatabase.TransactionType.RemoveFunds, TransactionSubType.Freeze);
if (accountsTable.Contains(accountID))
{
AccountLine account = accountsTable.Select(accountID);
lock (account)
{
if (balance > account.Balance)
{
freezeID = 0;
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InsufficientFunds;
status = LedgerOperationStatus.InsufficientFunds;
}
else
{
//update account balance and add freeze record
account.Balance -= balance;
FrozenBalanceLine frozenBalance = new FrozenBalanceLine(accountID, balance);
freezeID = frozenBalancesTable.Insert(frozenBalance);
}
}
}
else
{
freezeID = 0;
transaction.Status = LedgerDatabase.TransactionStatus.Rejected;
transaction.RejectReason = TransactionRejectReason.InvalidAccount;
status = LedgerOperationStatus.InvalidAccount;
}
transactionsTable.Insert(transaction);
return(status);
}