using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Text;
using HeuristicLab.Collections;
using HeuristicLab.Common;
using HeuristicLab.Common.Resources;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HeuristicLab.OKB.Client;
using HeuristicLab.Optimization;
using HeuristicLab.Persistence.Default.CompositeSerializers.Storable;
using HeuristicLab.Persistence.Default.Xml;

namespace HeuristicLab.OKB.AlgorithmHost {

  [Item("OKB Algorithm Host", "Load, run and submit values from and to the OKB")]
  [Creatable("Optimization Knowledge Base")]
  [StorableClass]
  public class AlgorithmHost : NamedItem, IAlgorithm {

    public override System.Drawing.Image ItemImage {
      get {
        if (ExecutionState == ExecutionState.Prepared) return VS2008ImageLibrary.ExecutablePrepared;
        else if (ExecutionState == ExecutionState.Started) return VS2008ImageLibrary.ExecutableStarted;
        else if (ExecutionState == ExecutionState.Paused) return VS2008ImageLibrary.ExecutablePaused;
        else if (ExecutionState == ExecutionState.Stopped) return VS2008ImageLibrary.ExecutableStopped;
        else return VS2008ImageLibrary.Event;
      }
    }

    [Storable]
    private IAlgorithm algorithm;
    public IAlgorithm Algorithm {
      get { return algorithm; }
      protected set {
        if (algorithm != value) {
          if (algorithm != null)
            DeregisterAlgorithmEvents();
          algorithm = value;
          if (algorithm != null) {
            algorithm.Problem = problem;
            RegisterAlgorithmEvents();
          }
          OnAlgorithmChanged();
          Prepare();
        }
      }
    }
    public event EventHandler AlgorithmChanged;

    #region constructors
    public AlgorithmHost() {
      name = ItemName;
      description = ItemDescription;
      executionState = ExecutionState.Stopped;
      executionTime = TimeSpan.Zero;
      Runs = new RunCollection();
    }

    public AlgorithmHost(string name)
      : base(name) {
      description = ItemDescription;
      executionState = ExecutionState.Stopped;
      executionTime = TimeSpan.Zero;
      Runs = new RunCollection();
    }

    public AlgorithmHost(string name, string description)
      : base(name, description) {
      executionState = ExecutionState.Stopped;
      executionTime = TimeSpan.Zero;
      Runs = new RunCollection();
    }

    [StorableConstructor]
    private AlgorithmHost(bool deserializing)
      : base(deserializing) {
    }
    #endregion

    #region Persistence
    [StorableHook(HookType.AfterDeserialization)]
    private void Initialize() {
      if (algorithm != null) RegisterAlgorithmEvents();
      if (runs != null) RegisterRunsEvents();
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      if (ExecutionState == ExecutionState.Started)
        throw new InvalidOperationException("Clone not allowed while algorithm host is running");
      AlgorithmHost clone = (AlgorithmHost)base.Clone(cloner);
      clone.executionState = executionState;
      clone.executionTime = executionTime;
      clone.algorithm = (IAlgorithm)cloner.Clone(algorithm);
      clone.runs = (RunCollection)cloner.Clone(runs);
      clone.Initialize();
      return clone;
    }
    #endregion

    #region OKB connection

    public OKBRunner.StarterKit StarterKit { get; set; }

    public OKBRunner.StarterKit DownloadStarerKit() {
      OKBRunner.RunnerServiceClient client =
        ClientFactory.Create<OKBRunner.RunnerServiceClient, OKBRunner.IRunnerService>();
      client.Login(Environment.MachineName);
      OKBRunner.StarterKit starterKit = client.GetStarterKit("HL 3.3");
      client.Logout();
      client.Close();
      return starterKit;
    }

    private ObservableDictionary<string, string> algorithmParameterMapping;
    private ObservableDictionary<string, string> resultMapping;

    private OKBRunner.Algorithm okbAlgorithm;
    public OKBRunner.Algorithm OKBAlgorithm {
      get {
        return okbAlgorithm;
      }
      internal set {
        if (value == okbAlgorithm) return;
        LoadAlgorithm(value.Id);
        okbAlgorithm = value;
      }
    }

    private ObservableDictionary<string, string> problemParameterMapping;
    private OKBRunner.Problem okbProblem;
    public OKBRunner.Problem OKBProblem {
      get {
        return okbProblem;
      }
      internal set {
        if (value == okbProblem) return;
        LoadProblem(value.Id);
        okbProblem = value;
      }
    }

    private void LoadAlgorithm(int id) {
      AlgorithmContainer algorithmContainer;
      using (var stream = new MemoryStream()) {
        Load(stream, OKBData.EntityType.Algorithm, id);
        stream.Seek(0, SeekOrigin.Begin);
        algorithmContainer = XmlParser.Deserialize<AlgorithmContainer>(stream);
      }
      Algorithm = algorithmContainer.Algorithm;
      algorithmParameterMapping = algorithmContainer.ParameterMapping;
      resultMapping = algorithmContainer.ResultMapping;
    }

    private void LoadProblem(int id) {
      ProblemContainer problemContainer;
      using (var stream = new MemoryStream()) {
        Load(stream, OKBData.EntityType.Problem, id);
        stream.Seek(0, SeekOrigin.Begin);
        problemContainer = XmlParser.Deserialize<ProblemContainer>(stream);
      }
      SetProblem(problemContainer.Problem, true);
      problemParameterMapping = problemContainer.ParameterMapping;
    }

    private void Load(Stream stream, OKBData.EntityType type, int id) {
      OKBData.DataServiceClient client = ClientFactory
       .Create<OKBData.DataServiceClient, OKBData.IDataService>();
      int total = client.Request(type, id);
      for (int length = 1; length > 0; ) {
        byte[] buffer = client.GetNextChunk(100);
        stream.Write(buffer, 0, buffer.Length);
        length = buffer.Length;
      }
      stream.Flush();
    }

    public OKBRunner.ExperimentKit PrepareSubmission(IRun run) {
      OKBRunner.ExperimentKit experimentKit = PrepareExperiment();
      Debug.Assert(run.Algorithm.Name == Algorithm.Name, "run algorithm must match current algorithm");
      Debug.Assert(run.Algorithm.Problem.Name == Problem.Name, "run problem must match current problem");
      SetParameters(run, experimentKit);
      SetResults(run, experimentKit);
      return experimentKit;
    }

    public void SubmitRun(OKBRunner.ExperimentKit experimentKit) {
      var client = ClientFactory.Create<OKBRunner.RunnerServiceClient, OKBRunner.IRunnerService>();
      client.Login(Environment.MachineName);
      client.AddRun(experimentKit.Algorithm, experimentKit.Problem, StarterKit.Projects.First());
      client.Logout();
      client.Close();
    }

    public static string FormatSubmission(OKBRunner.ExperimentKit experimentKit) {
      StringBuilder sb = new StringBuilder();
      sb.Append(experimentKit.Algorithm.Name).Append("@").AppendLine(experimentKit.Problem.Name);
      sb.AppendLine("Parameters:");
      foreach (var p in experimentKit.Algorithm.Algorithm_Parameters.Select(ap => ap.Parameter)) {
        sb.Append(p.Name).Append(": ");
        if (p.IntParameterValues != null && p.IntParameterValues.Count > 0)
          sb.Append(p.IntParameterValues[0].Value).AppendLine();
        else if (p.FloatParameterValues != null && p.FloatParameterValues.Count > 0)
          sb.Append(p.FloatParameterValues[0].Value).AppendLine();
        else if (p.CharParameterValues != null && p.CharParameterValues.Count > 0)
          sb.AppendLine(p.CharParameterValues[0].Value);
        else if (p.OperatorParameterValues != null && p.OperatorParameterValues.Count > 0)
          sb.Append('<').Append(p.OperatorParameterValues[0].DataType.ClrName).AppendLine(">");
        else
          sb.AppendLine("???");
      }
      sb.AppendLine("Results:");
      foreach (var r in experimentKit.Algorithm.Algorithm_Results.Select(ar => ar.Result)) {
        sb.Append(r.Name).Append(": ");
        if (r.IntResultValues != null && r.IntResultValues.Count > 0) {
          sb.Append(r.IntResultValues[0].Value).AppendLine();
        } else if (r.FloatResultValues != null && r.FloatResultValues.Count > 0) {
          sb.Append(r.FloatResultValues[0].Value).AppendLine();
        } else if (r.CharResultValues != null && r.CharResultValues.Count > 0) {
          sb.AppendLine(r.CharResultValues[0].Value);
        } else if (r.BlobResultValues != null && r.BlobResultValues.Count > 0) {
          sb.Append("byte[").Append(r.BlobResultValues[0].Value.Bytes.Length).AppendLine("]");
        } else
          sb.AppendLine("???");
      }
      return sb.ToString();
    }

    private void SetResults(IRun run, OKBRunner.ExperimentKit experimentKit) {
      var results = experimentKit.Algorithm.Algorithm_Results.Select(ar => ar.Result).ToList();
      experimentKit.Algorithm.Algorithm_Results.Clear();
      foreach (var r in results) {
        if (resultMapping.ContainsValue(r.Name)) {
          var rm = resultMapping.Single(kvp => kvp.Value == r.Name);
          if (run.Results.ContainsKey(rm.Key))
            experimentKit.Algorithm.AddResultValue(r.Name, run.Results[rm.Key]);
        }
      }
    }

    private void SetParameters(IRun run, OKBRunner.ExperimentKit experimentKit) {
      var algorithmParameters = experimentKit.Algorithm.Algorithm_Parameters.Select(ap => ap.Parameter).ToList();
      var problemParameters = experimentKit.Problem.Problem_Parameters.Select(pp => pp.Parameter).ToList();
      experimentKit.Algorithm.Algorithm_Parameters.Clear();
      foreach (var p in algorithmParameters) {
        if (algorithmParameterMapping.ContainsValue(p.Name)) {
          var pm = algorithmParameterMapping.Single(kvp => kvp.Value == p.Name);
          if (run.Algorithm.Parameters.ContainsKey(pm.Key)) {
            experimentKit.Algorithm.AddParameterValue(p.Name, run.Algorithm.Parameters[pm.Key].ActualValue);
          }
        }
      }

      foreach (var p in problemParameters) {
        if (problemParameterMapping.ContainsValue(p.Name)) {
          var pm = problemParameterMapping.Single(kvp => kvp.Value == p.Name);
          if (run.Algorithm.Problem.Parameters.ContainsKey(pm.Key)) {
            experimentKit.Algorithm.AddParameterValue(p.Name, run.Algorithm.Problem.Parameters[pm.Key].ActualValue);
          }
        }
      }
    }

    private OKBRunner.ExperimentKit PrepareExperiment() {
      OKBRunner.RunnerServiceClient client =
        ClientFactory.Create<OKBRunner.RunnerServiceClient, OKBRunner.IRunnerService>();
      client.Login(Environment.MachineName);
      OKBRunner.ExperimentKit experimentKit = client.PrepareExperiment(OKBAlgorithm, OKBProblem);
      client.Logout();
      client.Close();
      return experimentKit;
    }
    #endregion

    #region IAlgorithm Members

    public void CollectResultValues(IDictionary<string, IItem> values) {
      if (algorithm != null)
        algorithm.CollectResultValues(values);
    }

    public bool HasOKBProblem { get; protected set; }
    private IProblem problem;
    public IProblem Problem {
      get { return problem; }
      set { SetProblem(value, false); }
    }
    protected void SetProblem(IProblem value, bool isOkbProblem) {
      HasOKBProblem = isOkbProblem;
      if (value == problem) return;
      problem = value;
      if (algorithm != null)
        algorithm.Problem = value;
      OnProblemChanged();
    }

    public event EventHandler ProblemChanged;
    protected virtual void OnProblemChanged() {
      EventHandler handler = ProblemChanged;
      if (handler != null)
        handler(this, EventArgs.Empty);
    }


    public Type ProblemType {
      get { return algorithm != null ? algorithm.ProblemType : typeof(IProblem); }
    }

    public ResultCollection Results {
      get { return algorithm != null ? algorithm.Results : null; }
    }

    public bool StoreAlgorithmInEachRun {
      get { return algorithm.StoreAlgorithmInEachRun; }
      set {
        if (value != algorithm.StoreAlgorithmInEachRun) {
          algorithm.StoreAlgorithmInEachRun = value;
          OnStoreAlgorithmInEachRunChanged();
        }
      }
    }

    public event EventHandler StoreAlgorithmInEachRunChanged;
    protected virtual void OnStoreAlgorithmInEachRunChanged() {
      EventHandler handler = StoreAlgorithmInEachRunChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }

    #endregion

    #region IParameterizedItem Members

    public void CollectParameterValues(IDictionary<string, IItem> values) {
      if (algorithm != null)
        algorithm.CollectParameterValues(values);
    }

    public IKeyedItemCollection<string, IParameter> Parameters {
      get { return algorithm != null ? algorithm.Parameters : null; }
    }

    public IKeyedItemCollection<string, IParameter> ProblemParameters {
      get { return Problem != null ? Problem.Parameters : null; }
    }

    #endregion

    #region IOptimizer Members

    public void Prepare(bool clearRuns) {
      if ((ExecutionState != ExecutionState.Prepared) && (ExecutionState != ExecutionState.Paused) && (ExecutionState != ExecutionState.Stopped))
        throw new InvalidOperationException(string.Format("Prepare not allowed in execution state \"{0}\".", ExecutionState));
      if (Algorithm != null) {
        if (clearRuns) runs.Clear();
        Algorithm.Prepare(clearRuns);
      }
    }


    [Storable]
    private RunCollection runs;
    public RunCollection Runs {
      get { return runs; }
      private set {
        if (value == null) throw new ArgumentNullException();
        if (runs != value) {
          if (runs != null) DeregisterRunsEvents();
          runs = value;
          if (runs != null) RegisterRunsEvents();
        }
      }
    }

    #endregion

    #region IExecutable Members

    public event EventHandler<EventArgs<Exception>> ExceptionOccurred;

    [Storable]
    private ExecutionState executionState;
    public ExecutionState ExecutionState {
      get { return executionState; }
      private set {
        if (executionState != value) {
          executionState = value;
          OnExecutionStateChanged();
          OnItemImageChanged();
        }
      }
    }

    public event EventHandler ExecutionStateChanged;

    [Storable]
    private TimeSpan executionTime;
    public TimeSpan ExecutionTime {
      get {
        if ((Algorithm != null) && (Algorithm.ExecutionState != ExecutionState.Stopped))
          return executionTime + Algorithm.ExecutionTime;
        else
          return executionTime;
      }
      private set {
        executionTime = value;
        OnExecutionTimeChanged();
      }
    }

    public event EventHandler ExecutionTimeChanged;

    public void Pause() {
      if (ExecutionState != ExecutionState.Started)
        throw new InvalidOperationException(string.Format("Pause not allowed in execution state \"{0}\".", ExecutionState));
      if ((Algorithm != null) && (Algorithm.ExecutionState == ExecutionState.Started))
        Algorithm.Pause();
    }

    public event EventHandler Paused;

    public void Prepare() {
      Prepare(false);
    }

    public event EventHandler Prepared;

    public void Start() {
      if ((ExecutionState != ExecutionState.Prepared) && (ExecutionState != ExecutionState.Paused))
        throw new InvalidOperationException(string.Format("Start not allowed in execution state \"{0}\".", ExecutionState));
      if (Algorithm != null) Algorithm.Start();
    }

    public event EventHandler Started;

    public void Stop() {
      if ((ExecutionState != ExecutionState.Started) && (ExecutionState != ExecutionState.Paused))
        throw new InvalidOperationException(string.Format("Stop not allowed in execution state \"{0}\".", ExecutionState));
      if ((Algorithm != null) &&
          ((Algorithm.ExecutionState == ExecutionState.Started) || (Algorithm.ExecutionState == ExecutionState.Paused)))
        Algorithm.Stop();
    }

    public event EventHandler Stopped;

    #endregion

    #region events
    private void OnExecutionStateChanged() {
      EventHandler handler = ExecutionStateChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnExecutionTimeChanged() {
      EventHandler handler = ExecutionTimeChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnAlgorithmChanged() {
      EventHandler handler = AlgorithmChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnPrepared() {
      ExecutionState = ExecutionState.Prepared;
      EventHandler handler = Prepared;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnStarted() {
      ExecutionState = ExecutionState.Started;
      EventHandler handler = Started;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnPaused() {
      ExecutionState = ExecutionState.Paused;
      EventHandler handler = Paused;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnStopped() {
      ExecutionState = ExecutionState.Stopped;
      EventHandler handler = Stopped;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    private void OnExceptionOccurred(Exception exception) {
      EventHandler<EventArgs<Exception>> handler = ExceptionOccurred;
      if (handler != null) handler(this, new EventArgs<Exception>(exception));
    }
    private void RegisterAlgorithmEvents() {
      algorithm.ExceptionOccurred += new EventHandler<EventArgs<Exception>>(Algorithm_ExceptionOccurred);
      algorithm.ExecutionTimeChanged += new EventHandler(Algorithm_ExecutionTimeChanged);
      algorithm.Paused += new EventHandler(Algorithm_Paused);
      algorithm.Prepared += new EventHandler(Algorithm_Prepared);
      algorithm.Started += new EventHandler(Algorithm_Started);
      algorithm.Stopped += new EventHandler(Algorithm_Stopped);
      algorithm.Runs.CollectionReset += new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_CollectionReset);
      algorithm.Runs.ItemsAdded += new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_ItemsAdded);
      algorithm.Runs.ItemsRemoved += new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_ItemsRemoved);
      algorithm.ProblemChanged += new EventHandler(Algorithm_ProblemChanged);
    }

    private void DeregisterAlgorithmEvents() {
      algorithm.ExceptionOccurred -= new EventHandler<EventArgs<Exception>>(Algorithm_ExceptionOccurred);
      algorithm.ExecutionTimeChanged -= new EventHandler(Algorithm_ExecutionTimeChanged);
      algorithm.Paused -= new EventHandler(Algorithm_Paused);
      algorithm.Prepared -= new EventHandler(Algorithm_Prepared);
      algorithm.Started -= new EventHandler(Algorithm_Started);
      algorithm.Stopped -= new EventHandler(Algorithm_Stopped);
      algorithm.Runs.CollectionReset -= new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_CollectionReset);
      algorithm.Runs.ItemsAdded -= new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_ItemsAdded);
      algorithm.Runs.ItemsRemoved -= new CollectionItemsChangedEventHandler<IRun>(Algorithm_Runs_ItemsRemoved);
      algorithm.ProblemChanged -= new EventHandler(Algorithm_ProblemChanged);
    }
    private void Algorithm_ExceptionOccurred(object sender, EventArgs<Exception> e) {
      OnExceptionOccurred(e.Value);
    }
    private void Algorithm_ExecutionTimeChanged(object sender, EventArgs e) {
      OnExecutionTimeChanged();
    }
    private void Algorithm_Paused(object sender, EventArgs e) {
      OnPaused();
    }
    private void Algorithm_Prepared(object sender, EventArgs e) {
      OnPrepared();
    }
    private void Algorithm_Started(object sender, EventArgs e) {
      if (ExecutionState != ExecutionState.Started)
        OnStarted();
    }
    private void Algorithm_Stopped(object sender, EventArgs e) {
      ExecutionTime = Algorithm.ExecutionTime;
      OnStopped();
    }
    private void Algorithm_Runs_CollectionReset(object sender, CollectionItemsChangedEventArgs<IRun> e) {
      Runs.RemoveRange(e.OldItems);
      Runs.AddRange(e.Items);
    }
    private void Algorithm_Runs_ItemsAdded(object sender, CollectionItemsChangedEventArgs<IRun> e) {
      Runs.AddRange(e.Items);
    }
    private void Algorithm_Runs_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<IRun> e) {
      Runs.RemoveRange(e.Items);
    }
    void Algorithm_ProblemChanged(object sender, EventArgs e) {
      if (Algorithm.Problem == Problem)
        return;
      Problem = Algorithm.Problem;
    }

    private void RegisterRunsEvents() {
      runs.CollectionReset += new CollectionItemsChangedEventHandler<IRun>(Runs_CollectionReset);
      runs.ItemsRemoved += new CollectionItemsChangedEventHandler<IRun>(Runs_ItemsRemoved);
    }
    private void DeregisterRunsEvents() {
      runs.CollectionReset -= new CollectionItemsChangedEventHandler<IRun>(Runs_CollectionReset);
      runs.ItemsRemoved -= new CollectionItemsChangedEventHandler<IRun>(Runs_ItemsRemoved);
    }
    private void Runs_CollectionReset(object sender, CollectionItemsChangedEventArgs<IRun> e) {
      foreach (IRun run in e.OldItems) {
        IItem item;
        run.Results.TryGetValue("Execution Time", out item);
        TimeSpanValue executionTime = item as TimeSpanValue;
        if (executionTime != null) ExecutionTime -= executionTime.Value;
      }
      if (Algorithm != null) Algorithm.Runs.RemoveRange(e.OldItems);
      foreach (IRun run in e.Items) {
        IItem item;
        run.Results.TryGetValue("Execution Time", out item);
        TimeSpanValue executionTime = item as TimeSpanValue;
        if (executionTime != null) ExecutionTime += executionTime.Value;
      }
    }
    private void Runs_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<IRun> e) {
      foreach (IRun run in e.Items) {
        IItem item;
        run.Results.TryGetValue("Execution Time", out item);
        TimeSpanValue executionTime = item as TimeSpanValue;
        if (executionTime != null) ExecutionTime -= executionTime.Value;
      }
      if (Algorithm != null) Algorithm.Runs.RemoveRange(e.Items);
    }
    #endregion
  }
}