#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2012 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using HeuristicLab.Services.Hive.DataAccess;

namespace HeuristicLab.Services.Hive.Statistics.Controllers {
  public class ChartDataController : Controller {
    private static readonly TimeSpan DefaultDuration = new TimeSpan(1, 0, 0, 0);

    public JsonResult AverageCpuUtilization(DateTime? start = null, DateTime? end = null) {
      using (var db = new HiveDataContext(Settings.Default.HeuristicLab_Hive_LinqConnectionString)) {
        var data =
          from facts in GetClientFacts(db, start, end)
          select new {
            Time = facts.Key,
            CpuUtilization = facts.Average(x => x.CpuUtilization)
          };

        return Json(
          CreateSeriesData(data.ToList(), x => x.Time, x => x.CpuUtilization),
          JsonRequestBehavior.AllowGet);
      }
    }

    public JsonResult UsedCores(DateTime? start = null, DateTime? end = null) {
      using (var db = new HiveDataContext(Settings.Default.HeuristicLab_Hive_LinqConnectionString)) {
        var data =
          from facts in GetClientFacts(db, start, end)
          select new {
            Time = facts.Key,
            UsedCores = facts.Sum(x => x.NumUsedCores),
            TotalCores = facts.Sum(x => x.NumTotalCores)
          };

        return Json(
          CreateSeriesData(data.ToList(), x => x.Time, x => x.UsedCores, x => x.TotalCores),
          JsonRequestBehavior.AllowGet);
      }
    }

    public JsonResult UsedMemory(DateTime? start = null, DateTime? end = null) {
      using (var db = new HiveDataContext(Settings.Default.HeuristicLab_Hive_LinqConnectionString)) {
        var data =
          from facts in GetClientFacts(db, start, end)
          select new {
            Time = facts.Key,
            UsedMemory = facts.Sum(x => x.UsedMemory),
            TotalMemory = facts.Sum(x => x.TotalMemory)
          };

        return Json(
          CreateSeriesData(data.ToList(), x => x.Time, x => x.UsedMemory, x => x.TotalMemory),
          JsonRequestBehavior.AllowGet);
      }
    }

    private static IOrderedQueryable<IGrouping<DateTime, FactClientInfo>> GetClientFacts(HiveDataContext db, DateTime? start = null, DateTime? end = null) {
      start = start ?? DateTime.Now - DefaultDuration;
      end = end ?? DateTime.Now;

      return from ci in db.FactClientInfos
             where ci.DimTime.Time > start && ci.DimTime.Time < end
             group ci by ci.DimTime.Time into timeGroup
             orderby timeGroup.Key
             select timeGroup;
    }

    private static IEnumerable<IEnumerable<object[]>> CreateSeriesData<T>(IEnumerable<T> data, Func<T, DateTime> timeSelector, params Func<T, object>[] selectors) {
      return selectors.Select(selector =>
        data.Select(x => new[] {
          timeSelector(x).ToString("yyyy-MM-dd HH:mm"),
          selector(x)
        })
      );
    }
  }
}