public async Task Transfer(TransferCommand command)
{
if (!this.IsOpen())
{
throw new UnableToTransferFromAClosedAccountException();
}
if (this.State.Balance < command.Amount)
{
throw new InsufficientFundsException();
}
await this.WriteAsync(new TransferredEvent(command.ToAccountId, command.Amount)
{
RelationEvent = command.GetRelationKey()
});
}
