using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.UI.DataVisualization.Charting;
using DA = HeuristicLab.Services.Hive.DataAccess;
using DT = HeuristicLab.Services.Hive.DataTransfer;

namespace HeuristicLab.Services.Hive.WebRole {
  public partial class Status : System.Web.UI.Page {
    protected void Page_Load(object sender, EventArgs e) {
      var dao = ServiceLocator.Instance.HiveDao;
      var transactionManager = ServiceLocator.Instance.TransactionManager;
      var resourceName = Request.QueryString["resource"];
      IEnumerable<Guid> resourceIds = new List<Guid>();
      IEnumerable<DT.Slave> onlineSlaves = new List<DT.Slave>();
      int currentlyJobsWaiting = 0;

      if (!string.IsNullOrEmpty(resourceName)) {
        transactionManager.UseTransaction(() => {
          var resId = dao.GetResources(x => x.Name == resourceName).Single().Id;
          resourceIds = dao.GetChildResources(resId).Select(x => x.Id).Union(new List<Guid> { resId });
        }, false, false);
      } else {
        transactionManager.UseTransaction(() => {
          resourceIds = dao.GetResources(x => true).Select(y => y.Id);
        }, false, false);
      }

      transactionManager.UseTransaction(() => {
        onlineSlaves = dao.GetSlaves(x => (x.SlaveState == DA.SlaveState.Calculating || x.SlaveState == DA.SlaveState.Idle) && resourceIds.Contains(x.ResourceId));
      }, false, false);
      transactionManager.UseTransaction(() => {
        currentlyJobsWaiting = dao.GetTasks(x => x.State == DA.TaskState.Waiting).Count();
      }, false, false);

      int currentlyAvailableCores = onlineSlaves.Where(s => s.Cores.HasValue).Sum(s => s.Cores.Value);
      int currentlyUsedCores = currentlyAvailableCores - onlineSlaves.Where(s => s.FreeCores.HasValue).Sum(s => s.FreeCores.Value);

      this.availableCoresLabel.Text = currentlyAvailableCores.ToString();
      this.usedCoresLabel.Text = currentlyUsedCores.ToString();
      this.waitingJobsLabel.Text = currentlyJobsWaiting.ToString();

      slavesLabel.Text = string.Join(", ", onlineSlaves.Select(x => string.Format("<a href=\"?resource={0}\">{0}</a> ({1} %)", x.Name, Math.Round(x.CpuUtilization, 2))));

      cpuUtilizationLabel.Text = (onlineSlaves.Count() > 0 ? Math.Round(onlineSlaves.Average(s => s.CpuUtilization), 2).ToString() : "0.0") + " %";

      DT.Statistics[] stats = new DT.Statistics[0];
      transactionManager.UseTransaction(() => {
        if (daysDropDownList.SelectedValue == "All") {
          stats = dao.GetStatistics(x => true).OrderBy(x => x.TimeStamp).ToArray();
        } else {
          stats = dao.GetStatistics(x => x.Timestamp >= DateTime.Now.Subtract(TimeSpan.FromDays(int.Parse(daysDropDownList.SelectedValue)))).OrderBy(x => x.TimeStamp).ToArray();
        }
      }, false, false);

      for (int i = 0; i < stats.Length; i++) {
        var s = stats[i];
        var slaveStats = s.SlaveStatistics.Where(x => resourceIds.Contains(x.SlaveId));

        var averageCpuUtilization = slaveStats.Count() > 0 ? slaveStats.Average(x => x.CpuUtilization) : 0.0;
        cpuUtilizationChart.Series[0].Points.Add(new DataPoint(s.TimeStamp.ToOADate(), averageCpuUtilization));

        var cores = slaveStats.Sum(x => x.Cores);

        var usedCores = cores - slaveStats.Sum(x => x.FreeCores);
        coresChart.Series[0].Points.AddXY(s.TimeStamp.ToOADate(), cores);
        coresChart.Series[1].Points.AddXY(s.TimeStamp.ToOADate(), usedCores);

        var memory = slaveStats.Sum(x => x.Memory);
        var usedMemory = memory - slaveStats.Sum(x => x.FreeMemory);
        memoryChart.Series[0].Points.AddXY(s.TimeStamp.ToOADate(), memory / 1024.0);
        memoryChart.Series[1].Points.AddXY(s.TimeStamp.ToOADate(), usedMemory / 1024.0);
      }

    }
  }
}