#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2011 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.Configuration;
using System.IO;
using System.Linq;
using System.Threading;
using HeuristicLab.Clients.Hive.Jobs;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.PluginInfrastructure;

namespace HeuristicLab.Clients.Hive {
  // todo: rename from ExpMgrClient to ExperimentManagerClient
  [Item("ExperimentManagerClient", "Hive experiment manager client.")]
  public sealed class ExperimentManagerClient : IContent {
    private static ExperimentManagerClient instance;
    public static ExperimentManagerClient Instance {
      get {
        if (instance == null) instance = new ExperimentManagerClient();
        return instance;
      }
    }

    #region Properties
    private ItemCollection<HiveExperiment> hiveExperiments;
    public ItemCollection<HiveExperiment> HiveExperiments {
      get { return hiveExperiments; }
      set { hiveExperiments = value; }
    }

    private List<Plugin> onlinePlugins;
    public List<Plugin> OnlinePlugins {
      get { return onlinePlugins; }
      set { onlinePlugins = value; }
    }

    private List<Plugin> alreadyUploadedPlugins;
    public List<Plugin> AlreadyUploadedPlugins {
      get { return alreadyUploadedPlugins; }
      set { alreadyUploadedPlugins = value; }
    }
    #endregion

    public ExperimentManagerClient() { }

    #region Refresh
    public void Refresh() {
      OnRefreshing();

      hiveExperiments = new HiveItemCollection<HiveExperiment>();

      try {
        hiveExperiments.AddRange(ServiceLocator.Instance.CallHiveService<List<HiveExperiment>>(s => s.GetHiveExperiments()).OrderBy(x => x.Name));
      }
      finally {
        OnRefreshed();
      }
    }
    public void RefreshAsync(Action<Exception> exceptionCallback) {
      var call = new Func<Exception>(delegate() {
        try {
          Refresh();
        }
        catch (Exception ex) {
          return ex;
        }
        return null;
      });
      call.BeginInvoke(delegate(IAsyncResult result) {
        Exception ex = call.EndInvoke(result);
        if (ex != null) exceptionCallback(ex);
      }, null);
    }
    #endregion

    #region Store
    public static void Store(IHiveItem item) {
      if (item.Id == Guid.Empty) {
        if (item is HiveExperiment) {
          ExperimentManagerClient.Instance.UploadExperiment((HiveExperiment)item);
        }
      } else {
        if (item is HiveExperiment)
          ServiceLocator.Instance.CallHiveService(s => s.UpdateHiveExperiment((HiveExperiment)item));
      }
    }
    public static void StoreAsync(Action<Exception> exceptionCallback, IHiveItem item) {
      var call = new Func<Exception>(delegate() {
        try {
          Store(item);
        }
        catch (Exception ex) {
          return ex;
        }
        return null;
      });
      call.BeginInvoke(delegate(IAsyncResult result) {
        Exception ex = call.EndInvoke(result);
        if (ex != null) exceptionCallback(ex);
      }, null);
    }
    #endregion

    #region Delete
    public static void Delete(IHiveItem item) {
      if (item is HiveExperiment)
        ServiceLocator.Instance.CallHiveService(s => s.DeleteHiveExperiment(item.Id));
      item.Id = Guid.Empty;
    }
    #endregion

    #region Events
    public event EventHandler Refreshing;
    private void OnRefreshing() {
      EventHandler handler = Refreshing;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler Refreshed;
    private void OnRefreshed() {
      var handler = Refreshed;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    #endregion

    public static void StartExperiment(Action<Exception> exceptionCallback, HiveExperiment hiveExperiment) {
      ExperimentManagerClient.StoreAsync(
        new Action<Exception>((Exception ex) => {
          hiveExperiment.ExecutionState = ExecutionState.Prepared;
          exceptionCallback(ex);
        }), hiveExperiment);
      hiveExperiment.ExecutionState = ExecutionState.Started;
    }

    public static void PauseExperiment(HiveExperiment hiveExperiment) {
      ServiceLocator.Instance.CallHiveService(service => {
        foreach (HiveJob job in hiveExperiment.GetAllHiveJobs()) {
          if (job.Job.State != JobState.Finished && job.Job.State != JobState.Aborted && job.Job.State != JobState.Failed)
            service.PauseJob(job.Job.Id);
        }
      });
      hiveExperiment.ExecutionState = ExecutionState.Paused;
    }

    public static void StopExperiment(HiveExperiment hiveExperiment) {
      ServiceLocator.Instance.CallHiveService(service => {
        foreach (HiveJob job in hiveExperiment.GetAllHiveJobs()) {
          if (job.Job.State != JobState.Finished && job.Job.State != JobState.Aborted && job.Job.State != JobState.Failed)
            service.StopJob(job.Job.Id);
        }
      });
      // execution state does not need to be set. it will be set to Stopped, when all jobs have been downloaded
    }

    #region Upload Experiment
    private void UploadExperiment(HiveExperiment hiveExperiment) {
      try {
        hiveExperiment.Progress = new Progress("Connecting to server...");
        hiveExperiment.IsProgressing = true;
        ServiceLocator.Instance.CallHiveService(service => {
          IEnumerable<string> resourceNames = ToResourceNameList(hiveExperiment.ResourceNames);
          var resourceIds = new List<Guid>();
          foreach (var resourceName in resourceNames) {
            Guid resourceId = service.GetResourceId(resourceName);
            if (resourceId == Guid.Empty) {
              throw new ResourceNotFoundException(string.Format("Could not find the resource '{0}'", resourceName));
            }
            resourceIds.Add(resourceId);
          }

          foreach (HiveJob hiveJob in hiveExperiment.HiveJobs) {
            hiveJob.SetIndexInParentOptimizerList(null);
          }

          // upload HiveExperiment
          hiveExperiment.Progress.Status = "Uploading HiveExperiment...";
          hiveExperiment.Id = service.AddHiveExperiment(hiveExperiment);

          int totalJobCount = hiveExperiment.GetAllHiveJobs().Count();
          int jobCount = 0;

          // upload plugins
          hiveExperiment.Progress.Status = "Uploading plugins...";
          this.OnlinePlugins = service.GetPlugins();
          this.AlreadyUploadedPlugins = new List<Plugin>();
          Plugin configFilePlugin = UploadConfigurationFile(service);
          this.alreadyUploadedPlugins.Add(configFilePlugin);

          // upload jobs
          hiveExperiment.Progress.Status = "Uploading jobs...";

          foreach (HiveJob hiveJob in hiveExperiment.HiveJobs) {
            UploadJobWithChildren(hiveExperiment.Progress, service, hiveJob, null, resourceIds, ref jobCount, totalJobCount, configFilePlugin.Id, hiveExperiment.UseLocalPlugins, hiveExperiment.Id);
          }

          if (hiveExperiment.RefreshAutomatically) hiveExperiment.StartResultPolling();
        });
      }
      finally {
        hiveExperiment.IsProgressing = false;
      }
    }

    /// <summary>
    /// Uploads the local configuration file as plugin
    /// </summary>
    private static Plugin UploadConfigurationFile(IHiveService service) {
      string exeFilePath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "HeuristicLab 3.3.exe");
      string configFileName = Path.GetFileName(ConfigurationManager.OpenExeConfiguration(exeFilePath).FilePath);
      string configFilePath = ConfigurationManager.OpenExeConfiguration(exeFilePath).FilePath;

      Plugin configPlugin = new Plugin() {
        Name = "Configuration",
        IsLocal = true,
        Version = new Version()
      };
      PluginData configFile = new PluginData() {
        FileName = configFileName,
        Data = File.ReadAllBytes(configFilePath)
      };
      configPlugin.Id = service.AddPlugin(configPlugin, new List<PluginData> { configFile });
      return configPlugin;
    }

    /// <summary>
    /// Uploads the given job and all its child-jobs while setting the proper parentJobId values for the childs
    /// </summary>
    /// <param name="service"></param>
    /// <param name="hiveJob"></param>
    /// <param name="parentHiveJob">shall be null if its the root job</param>
    /// <param name="groups"></param>
    private void UploadJobWithChildren(IProgress progress, IHiveService service, HiveJob hiveJob, HiveJob parentHiveJob, IEnumerable<Guid> groups, ref int jobCount, int totalJobCount, Guid configPluginId, bool useLocalPlugins, Guid hiveExperimentId) {
      jobCount++;
      progress.Status = string.Format("Serializing job {0} of {1}", jobCount, totalJobCount);
      JobData jobData;
      List<IPluginDescription> plugins;

      if (hiveJob.OptimizerJob.ComputeInParallel &&
        (hiveJob.OptimizerJob.Optimizer is Optimization.Experiment || hiveJob.OptimizerJob.Optimizer is Optimization.BatchRun)) {
        hiveJob.Job.IsParentJob = true;
        hiveJob.Job.FinishWhenChildJobsFinished = true;
        hiveJob.OptimizerJob.CollectChildJobs = false; // don't collect child-jobs on slaves
        jobData = hiveJob.GetAsJobData(true, out plugins);
      } else {
        hiveJob.Job.IsParentJob = false;
        hiveJob.Job.FinishWhenChildJobsFinished = false;
        jobData = hiveJob.GetAsJobData(false, out plugins);
      }

      hiveJob.Job.PluginsNeededIds = PluginUtil.GetPluginDependencies(service, this.onlinePlugins, this.alreadyUploadedPlugins, plugins, useLocalPlugins);
      hiveJob.Job.PluginsNeededIds.Add(configPluginId);
      hiveJob.Job.HiveExperimentId = hiveExperimentId;

      progress.Status = string.Format("Uploading job {0} of {1} ({2} kb)", jobCount, totalJobCount, jobData.Data.Count() / 1024);
      progress.ProgressValue = (double)jobCount / totalJobCount;

      if (parentHiveJob != null) {
        hiveJob.Job.Id = service.AddChildJob(parentHiveJob.Job.Id, hiveJob.Job, jobData);
      } else {
        hiveJob.Job.Id = service.AddJob(hiveJob.Job, jobData, groups.ToList());
      }

      foreach (HiveJob child in hiveJob.ChildHiveJobs) {
        UploadJobWithChildren(progress, service, child, hiveJob, groups, ref jobCount, totalJobCount, configPluginId, useLocalPlugins, hiveExperimentId);
      }
    }
    #endregion

    #region Download Experiment
    public static void LoadExperiment(HiveExperiment hiveExperiment) {
      hiveExperiment.Progress = new Progress();
      try {
        hiveExperiment.IsProgressing = true;
        int totalJobCount = 0;
        IEnumerable<LightweightJob> allJobs;

        hiveExperiment.Progress.Status = "Connecting to Server...";
        // fetch all Job objects to create the full tree of tree of HiveJob objects
        hiveExperiment.Progress.Status = "Downloading list of jobs...";
        allJobs = ServiceLocator.Instance.CallHiveService(s => s.GetLightweightExperimentJobs(hiveExperiment.Id));
        totalJobCount = allJobs.Count();

        HiveJobDownloader downloader = new HiveJobDownloader(allJobs.Select(x => x.Id));
        downloader.StartAsync();

        while (!downloader.IsFinished) {
          hiveExperiment.Progress.ProgressValue = downloader.FinishedCount / (double)totalJobCount;
          hiveExperiment.Progress.Status = string.Format("Downloading/deserializing jobs... ({0}/{1} finished)", downloader.FinishedCount, totalJobCount);
          Thread.Sleep(500);
        }
        IDictionary<Guid, HiveJob> allHiveJobs = downloader.Results;

        hiveExperiment.HiveJobs = new ItemCollection<HiveJob>(allHiveJobs.Values.Where(x => !x.Job.ParentJobId.HasValue));
        //hiveExperiment.HiveJobs = allHiveJobs[hiveExperiment.RootJobId];

        if (hiveExperiment.IsFinished()) {
          //hiveExperiment.ExecutionTime = hiveExperiment.HiveJobs.Max(.Job.DateFinished.Value - hiveExperiment.HiveJobs.Job.DateCreated.Value;
          //hiveExperiment.lastUpdateTime = hiveExperiment.HiveJob.Job.DateFinished.Value;
          hiveExperiment.ExecutionState = Core.ExecutionState.Stopped;
          //OnStopped(); // todo: stop timer
        } else {
          //hiveExperiment.ExecutionTime = hiveExperiment.HiveJobs.Job.DateCreated.HasValue ? DateTime.Now - hiveExperiment.HiveJobs.Job.DateCreated.Value : TimeSpan.Zero;
          //hiveExperiment.lastUpdateTime = DateTime.Now;
          hiveExperiment.ExecutionState = Core.ExecutionState.Started;
          //OnStarted(); // todo: start timer
        }
        hiveExperiment.UpdateTotalExecutionTime();

        // build child-job tree
        foreach (HiveJob hiveJob in hiveExperiment.HiveJobs) {
          BuildHiveJobTree(hiveJob, allJobs, allHiveJobs);
        }
        hiveExperiment.UpdateTotalExecutionTime();

        if (hiveExperiment.ExecutionState != ExecutionState.Stopped) {
          hiveExperiment.RefreshAutomatically = true;
        }
      }
      finally {
        hiveExperiment.IsProgressing = false;
      }
    }

    private static void BuildHiveJobTree(HiveJob parentHiveJob, IEnumerable<LightweightJob> allJobs, IDictionary<Guid, HiveJob> allHiveJobs) {
      IEnumerable<LightweightJob> childJobs = from job in allJobs
                                              where job.ParentJobId.HasValue && job.ParentJobId.Value == parentHiveJob.Job.Id
                                              orderby job.DateCreated ascending
                                              select job;
      foreach (LightweightJob job in childJobs) {
        HiveJob childHiveJob = allHiveJobs[job.Id];
        parentHiveJob.AddChildHiveJob(childHiveJob);
        BuildHiveJobTree(childHiveJob, allJobs, allHiveJobs);
      }
    }
    #endregion

    /// <summary>
    /// Converts a string which can contain Ids separated by ';' to a enumerable
    /// </summary>
    private static IEnumerable<string> ToResourceNameList(string resourceNames) {
      if (!string.IsNullOrEmpty(resourceNames)) {
        return resourceNames.Split(';');
      } else {
        return new List<string>();
      }
    }

    public static OptimizerJob LoadOptimizerJob(Guid jobId) {
      JobData jobData = ServiceLocator.Instance.CallHiveService(s => s.GetJobData(jobId));
      try {
        return PersistenceUtil.Deserialize<OptimizerJob>(jobData.Data);
      }
      catch {
        return null;
      }
    }
  }
}