#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2008 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.Text;
using HeuristicLab.Hive.Contracts.Interfaces;
using HeuristicLab.Hive.Contracts.BusinessObjects;
using HeuristicLab.Hive.Contracts;
using HeuristicLab.Hive.Server.Core.InternalInterfaces.DataAccess;
using HeuristicLab.Hive.Server.Core.InternalInterfaces;

namespace HeuristicLab.Hive.Server.Core {
  class JobManager: IJobManager, IInternalJobManager {

    IJobAdapter jobAdapter;
    IJobResultsAdapter jobResultAdapter;
    ILifecycleManager lifecycleManager;

    #region IJobManager Members

    public JobManager() {
      jobAdapter = ServiceLocator.GetJobAdapter();
      jobResultAdapter = ServiceLocator.GetJobResultsAdapter();

      lifecycleManager = ServiceLocator.GetLifecycleManager();

      lifecycleManager.RegisterStartup(new EventHandler(lifecycleManager_OnStartup));
      lifecycleManager.RegisterStartup(new EventHandler(lifecycleManager_OnShutdown));
    }

    public void ResetJobsDependingOnResults(Job job) {
      List<JobResult> allJobResults = new List<JobResult>(jobResultAdapter.GetResultsOf(job));
      JobResult lastJobResult = null;
      foreach (JobResult jR in allJobResults) {
        // if lastJobResult was before the current jobResult the lastJobResult must be updated
        if (lastJobResult == null ||          
            (jR.timestamp > lastJobResult.timestamp))
          lastJobResult = jR;
      }
      if (lastJobResult != null) {
        job.Percentage = lastJobResult.Percentage;
        job.SerializedJob = lastJobResult.Result;
      } else {
        job.Percentage = 0;
      }

      job.Client = null;
      job.State = State.offline;

      jobAdapter.Update(job);
    }

    void checkForDeadJobs() {
      List<Job> allJobs = new List<Job>(jobAdapter.GetAll());
      foreach (Job curJob in allJobs) {
        if (curJob.State == State.calculating) {
          ResetJobsDependingOnResults(curJob);
        }
      }
    }

    void lifecycleManager_OnStartup(object sender, EventArgs e) {
      checkForDeadJobs();
    }

    void lifecycleManager_OnShutdown(object sender, EventArgs e) {
      checkForDeadJobs();
    }

    /// <summary>
    /// returns all jobs stored in the database
    /// </summary>
    /// <returns></returns>
    public ResponseList<Job> GetAllJobs() {
      ResponseList<Job> response = new ResponseList<Job>();

      response.List = new List<Job>(jobAdapter.GetAll());
      response.Success = true;
      response.StatusMessage = ApplicationConstants.RESPONSE_JOB_ALL_JOBS;
      
      return response;
    }

    /// <summary>
    /// Adds a new job into the database
    /// </summary>
    /// <param name="job"></param>
    /// <returns></returns>
    public ResponseObject<Job> AddNewJob(Job job) {
      ResponseObject<Job> response = new ResponseObject<Job>();

      if (job != null) {
        if (job.State != State.offline) {
          response.Success = false;
          response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOBSTATE_MUST_BE_OFFLINE;
          return response;
        }
        if (job.Id != 0) {
          response.Success = false;
          response.StatusMessage = ApplicationConstants.RESPONSE_JOB_ID_MUST_NOT_BE_SET;
          return response;
        }
        if (job.SerializedJob == null) {
          response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOB_NULL;
          response.Success = false;
          return response;
        }

        jobAdapter.Update(job);
        response.Success = true;
        response.Obj = job;
        response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOB_ADDED;
      } else {
        response.Success = false;
        response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOB_NULL;
      }

      return response;
    }

    /// <summary>
    /// Removes a job from the database
    /// </summary>
    /// <param name="jobId"></param>
    /// <returns></returns>
    public Response RemoveJob(long jobId) {
      Response response = new Response();

      Job job = jobAdapter.GetById(jobId);
      if (job == null) {
        response.Success = false;
        response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOB_DOESNT_EXIST;
        return response;
      }
      jobAdapter.Delete(job);
      response.Success = false;
      response.StatusMessage = ApplicationConstants.RESPONSE_JOB_JOB_REMOVED;

      return response;
    }

    #endregion
  }
}