public async Task <IEnumerable <NotificationDto> > GetNotifications(string userId, int?limit)
{
if (limit != null && limit < 0)
{
throw new ArgumentException("Limit must be a non-negative number");
}
var notifications = await _context.Notifications
.Where(n => n.ReceiverId.Equals(userId) && n.TopicId != null)
.OrderByDescending(n => n.CreatedAt)
.Include(n => n.Sender)
.Include(n => n.Topic)
.Include(n => n.Comment)
.ToListAsync();
var output = new List <NotificationDto>();
foreach (var notification in notifications.GroupBy(c => new { c.Type, c.TopicId, c.CommentId }).Select(n => n.ToList()))
{
var first = notification.First();
if (first.Comment == null && first.CommentId != null || first.Topic.IsDeleted)
{
continue;
}
var count = notification.GroupBy(n => n.SenderId).Select(n => n.FirstOrDefault()).Count();
output.Add(NotificationDto.Create(first, count - 1));
}
return(limit == null?output.Where(n => !n.IsRead) : output.Skip((int)limit).Take(5));
}
private async Task Notify(Notification notification, ApplicationUser sender, Topic topic, Comment comment = null)
{
try
{
await Do(async() => await _context.Notifications.AddAsync(notification));
_notificationsHub.Notify(notification.ReceiverId, NotificationDto.Create(notification, sender, topic, comment));
}
catch
{
// ignored
}
}