public async Task <Unit> Handle(CancelPaymentCommand request, CancellationToken cancellationToken)
{
var entity = await _context.Payments
.SingleOrDefaultAsync(i => i.Id == request.Id && i.CustomerId == _currentUser.UserId, cancellationToken);
if (entity == null)
{
throw new ValidationException("Id", "Invalid payment id.");
}
if (entity.Status == PaymentStatus.Processed)
{
throw new ValidationException("Status", "Payment has been processed already.");
}
if (entity.Status == PaymentStatus.Closed)
{
return(Unit.Value);
}
entity.Status = PaymentStatus.Closed;
entity.Comment = request.Reason;
await _context.SaveChangesAsync(cancellationToken);
await _mediator.Publish(new PaymentCancelled
{
PaymentId = entity.Id,
Reason = request.Reason
}, cancellationToken);
return(Unit.Value);
}
public async Task <Guid> Handle(CreatePaymentCommand request, CancellationToken cancellationToken)
{
var customer = await _mediator.Send(new GetCustomerQuery { Id = _currentUser.UserId }, cancellationToken);
if (customer == null)
{
throw new ValidationException("CustomerId", "Invalid customer id.");
}
var hasSufficientBalance = customer.Balance >= request.Amount;
var entity = new Payment
{
Amount = request.Amount,
Comment = hasSufficientBalance ? "" : "Not enough funds",
CustomerId = _currentUser.UserId,
Date = request.Date,
Status = hasSufficientBalance ? PaymentStatus.Pending : PaymentStatus.Closed,
};
await _context.Payments.AddAsync(entity, cancellationToken);
await _context.SaveChangesAsync(cancellationToken);
await _mediator.Publish(new PaymentCreated { Amount = request.Amount, PaymentId = entity.Id }, cancellationToken);
return(entity.Id);
}
public async Task <bool> Handle(ReduceBalanceCommand request, CancellationToken cancellationToken)
{
var entity = await _context.Customers.SingleOrDefaultAsync(i => i.Id == _currentUser.UserId, cancellationToken);
if (entity == null)
{
throw new ValidationException("Id", "Invalid customer id.");
}
if (entity.Balance < request.ReduceAmount)
{
return(false);
}
entity.Balance -= request.ReduceAmount;
await _context.SaveChangesAsync(cancellationToken);
return(true);
}
public async Task <Unit> Handle(ProcessPaymentCommand request, CancellationToken cancellationToken)
{
var entity = await _context.Payments
.SingleOrDefaultAsync(i => i.Id == request.Id && i.CustomerId == _currentUser.UserId, cancellationToken);
if (entity == null)
{
throw new ValidationException("Id", "Invalid payment id.");
}
if (entity.Status == PaymentStatus.Closed)
{
throw new ValidationException("Status", "Can't process the closed payment.");
}
if (entity.Status == PaymentStatus.Processed)
{
return(Unit.Value);
}
var balanceReduced = await _mediator.Send(new ReduceBalanceCommand { ReduceAmount = entity.Amount }, cancellationToken);
if (!balanceReduced)
{
entity.Status = PaymentStatus.Closed;
entity.Comment = "Not enough funds";
}
else
{
entity.Status = PaymentStatus.Processed;
}
await _context.SaveChangesAsync(cancellationToken);
await _mediator.Publish(new PaymentProcessed { PaymentId = entity.Id }, cancellationToken);
return(Unit.Value);
}