source: branches/HiveStatistics/sources/HeuristicLab.Services.Hive/3.3/HiveStatisticsGenerator.cs @ 9533

using System;
using System.Linq;
using System.Transactions;
using HeuristicLab.Services.Hive.DataAccess;

namespace HeuristicLab.Services.Hive {
  public class HiveStatisticsGenerator : IStatisticsGenerator {
    private static readonly TimeSpan SmallesTimeSpan = new TimeSpan(0, 5, 0);

    public void GenerateStatistics() {
      using (var db = new HiveDataContext(Settings.Default.HeuristicLab_Hive_LinqConnectionString))
      using (var transaction = new TransactionScope()) {

        var newTime = UpdateDimensionTables(db);
        if (newTime != null) {
          UpdateDataTables(newTime, db);
        }

        db.SubmitChanges();
        transaction.Complete();
      }
    }

    private DimTime UpdateDimensionTables(HiveDataContext db) {
      var newTime = UpdateTime(db);
      // Update other tables out of sync with time dimension?
      UpdateJobs(db);
      UpdateUsers(db);
      // UpdateClients

      return newTime;
    }

    private DimTime UpdateTime(HiveDataContext db) {
      var lastUpdate =
        (from t in db.DimTimes
         orderby t.Time descending
         select t.Time)
        .FirstOrDefault();

      var now = DateTime.Now;
      DimTime newTime = null;
      if (lastUpdate == default(DateTime) || lastUpdate + SmallesTimeSpan < now) {
        newTime = new DimTime {
          Time = new DateTime(now.Year, now.Month, now.Day, now.Hour, now.Minute - now.Minute % SmallesTimeSpan.Minutes, 0),
          Hour = new DateTime(now.Year, now.Month, now.Day, now.Hour, 0, 0),
          Day = new DateTime(now.Year, now.Month, now.Day, 0, 0, 0),
          Week = new DateTime(now.Year, now.Month, now.Day - (int)now.DayOfWeek, 0, 0, 0), // Week begins with Sunday
          Month = new DateTime(now.Year, now.Month, 1, 0, 0, 0),
          Year = new DateTime(now.Year, 1, 1, 0, 0, 0)
        };
        db.DimTimes.InsertOnSubmit(newTime);
      }

      return newTime;
    }

    private void UpdateJobs(HiveDataContext db) {
      var newJobs =
        from j in db.Jobs
        where !db.DimJobs.Select(x => x.JobId).Contains(j.JobId)
        select j;

      var newDimJobs =
        from j in newJobs.ToList()
        select new DimJob {
          JobId = j.JobId,
          JobName = j.Name,
          UserId = j.OwnerUserId,
          UserName = ""
        };

      db.DimJobs.InsertAllOnSubmit(newDimJobs);
    }

    private void UpdateUsers(HiveDataContext db) {
      var newUsers =
        from u in db.Resources.Where(x => x.OwnerUserId != null).Select(x => x.OwnerUserId.Value).Union(db.Jobs.Select(x => x.OwnerUserId))
        where !db.DimUsers.Select(x => x.UserId).Contains(u)
        select u;

      var newDimUsers =
        from u in newUsers.ToList()
        select new DimUser {
          UserId = u,
          Name = ""
        };

      db.DimUsers.InsertAllOnSubmit(newDimUsers);
    }

    private void UpdateDataTables(DimTime newTime, HiveDataContext db) {

    }
  }
}