public static IEnumerable<ReportProjectModel> Create(int reportId, IEnumerable<int> userIds, DateTime startDate, DateTime endDate)
        {
            _context = FollowUpConnectionFactory.GetConnection();

            var reportProjects = _context.ReportProjects.Where(r => r.ReportID == reportId);

            var projects = new List<Project>();
            foreach (var reportProject in reportProjects)
            {
                if (reportProject.Project == null)
                    projects.AddRange(_context.Projects.Where(p => p.ClientID == reportProject.ClientID));
                else
                    projects.Add(reportProject.Project);
            }

           var rawData = from p in projects
                                     join a in _context.Articles on p.ProjectID equals a.ArticleID
                                     join w in _context.WorkSpecifications on p.ProjectID equals w.ProjectID
                                     join u in _context.Users on w.UserID equals u.UserID
                                     join wh in _context.WorkHours on w.WorkSpecificationID equals wh.WorkSpecificationID
                                     orderby p.ProjectName, a.ArticleName, w.WorkDate, u.FirstName
                                     where
                                         userIds.Contains(u.UserID)
                                         && wh.Hours > 0
                                         && w.WorkDate <= endDate
                                         && w.WorkDate >= startDate
                                      let firstOrDefault = wh.Article.Prices.FirstOrDefault(pr => pr.StartDate <= wh.WorkSpecification.WorkDate
                                                && (pr.EndDate ?? DateTime.MaxValue) >= wh.WorkSpecification.WorkDate)
                                      where firstOrDefault != null
                                      select new
                                                {
                                                    BillableHours = wh.BillableHours ?? wh.Hours,
                                                    Id = p.ProjectID,
                                                    ProjectHours = wh.Hours,
                                                    ProjectName = p.ProjectName,
                                                    ProjectPrice = (wh.BillableHours ?? wh.Hours)* firstOrDefault.PricePerHour,
                                                    ReportUserModels = new
                                                                           {
                                                                               BillableHours = wh.BillableHours ?? wh.Hours,
                                                                               Id = u.UserID,
                                                                               PriceForPeriod = (wh.BillableHours ?? wh.Hours) * firstOrDefault.PricePerHour,
                                                                               UserName = u.FirstName + " " + u.LastName,
                                                                               WorkedHours = wh.Hours
                                                                           }
                                                };

            var result = from rpm in rawData
                         group rpm by new {rpm.Id, rpm.ProjectName}
                         into project
                         select new ReportProjectModel
                                    {
                                        Id = project.Key.Id,
                                        ProjectName = project.Key.ProjectName,

                                        BillableHours = project.Sum(p => p.BillableHours),
                                        ProjectHours = project.Sum(p => p.ProjectHours),
                                        ProjectPrice = project.Sum(p => p.ProjectPrice),

                                        ReportUserModels = project.GroupBy(p => new { p.ReportUserModels.Id, p.ReportUserModels.UserName }, p => p.ReportUserModels)
                                                                  .Select(rum => new ReportUserModel
                                                                    {
                                                                        Id = rum.Key.Id,
                                                                        UserName = rum.Key.UserName,
                                                                        PriceForPeriod = rum.Sum(oneUser => oneUser.PriceForPeriod),
                                                                        BillableHours = rum.Sum(oneUser => oneUser.BillableHours),
                                                                        WorkedHours = rum.Sum(oneUser => oneUser.WorkedHours)
                                                                    })
                                    };


#if DEBUG
            result = result.ToArray();
#endif

                return result;

        }