#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2019 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.ComponentModel;
using System.Linq;
using HeuristicLab.Collections;
using HeuristicLab.Common;
using HeuristicLab.Core;
using HeuristicLab.Data;
using HEAL.Fossil;

namespace HeuristicLab.Optimization {
  [Item("Run Collection", "Represents a collection of runs.")]
  [Creatable(CreatableAttribute.Categories.TestingAndAnalysis, Priority = 120)]
  [StorableType("6A9E959B-62DB-4998-BFC6-BF3BAE66BED4")]
  public class RunCollection : ItemCollection<IRun>, IStringConvertibleMatrix, IStorableContent {
    public string Filename { get; set; }

    [StorableConstructor]
    protected RunCollection(StorableConstructorFlag _) : base(_) {
      updateOfRunsInProgress = false;
    }
    protected RunCollection(RunCollection original, Cloner cloner)
      : base(original, cloner) {
      updateOfRunsInProgress = false;
      optimizerName = original.optimizerName;

      resultNames = new List<string>(original.resultNames);
      parameterNames = new List<string>(original.parameterNames);
      dataTypes = new Dictionary<string, HashSet<Type>>();
      foreach (string s in original.dataTypes.Keys)
        dataTypes[s] = new HashSet<Type>(original.dataTypes[s]);

      constraints = new RunCollectionConstraintCollection(original.constraints.Select(x => cloner.Clone(x)));
      modifiers = new CheckedItemList<IRunCollectionModifier>(original.modifiers.Select(cloner.Clone));
      foreach (IRunCollectionConstraint constraint in constraints)
        constraint.ConstrainedValue = this;
      RegisterConstraintsEvents();
      RegisterConstraintEvents(constraints);

      foreach (var run in this) {
        RegisterRunParametersEvents(run);
        RegisterRunResultsEvents(run);
      }

      UpdateFiltering(true);
    }
    public RunCollection() : base() { Initialize(); }
    public RunCollection(int capacity) : base(capacity) { Initialize(); }
    public RunCollection(IEnumerable<IRun> collection) : base(collection) { Initialize(); this.OnItemsAdded(collection); }
    private void Initialize() {
      updateOfRunsInProgress = false;
      parameterNames = new List<string>();
      resultNames = new List<string>();
      dataTypes = new Dictionary<string, HashSet<Type>>();
      constraints = new RunCollectionConstraintCollection();
      modifiers = new CheckedItemList<IRunCollectionModifier>();
      RegisterConstraintsEvents();
    }

    [Storable]
    private Dictionary<string, HashSet<Type>> dataTypes;
    public IEnumerable<Type> GetDataType(string columnName) {
      if (!dataTypes.ContainsKey(columnName))
        return new Type[0];
      return dataTypes[columnName];
    }

    [Storable]
    private RunCollectionConstraintCollection constraints;
    public RunCollectionConstraintCollection Constraints {
      get { return constraints; }
    }

    [Storable]
    private CheckedItemList<IRunCollectionModifier> modifiers;
    public CheckedItemList<IRunCollectionModifier> Modifiers {
      get { return modifiers; }
    }


    private bool updateOfRunsInProgress;
    public bool UpdateOfRunsInProgress {
      get { return updateOfRunsInProgress; }
      set {
        if (updateOfRunsInProgress != value) {
          updateOfRunsInProgress = value;
          OnUpdateOfRunsInProgressChanged();
        }
      }
    }

    private string optimizerName = string.Empty;
    [Storable]
    public string OptimizerName {
      get { return optimizerName; }
      set {
        if (value != optimizerName && !string.IsNullOrEmpty(value)) {
          optimizerName = value;
          OnOptimizerNameChanged();
        }
      }
    }

    // BackwardsCompatibility3.3
    #region Backwards compatible code, remove with 3.4
    [Storable(AllowOneWay = true)]
    private string AlgorithmName {
      set { optimizerName = value; }
    }
    #endregion

    [StorableHook(HookType.AfterDeserialization)]
    private void AfterDeserialization() {
      if (constraints == null) constraints = new RunCollectionConstraintCollection();
      if (modifiers == null) modifiers = new CheckedItemList<IRunCollectionModifier>();
      RegisterConstraintsEvents();
      RegisterConstraintEvents(constraints);

      foreach (var run in this) {
        RegisterRunParametersEvents(run);
        RegisterRunResultsEvents(run);
      }
      UpdateFiltering(true);
    }

    public override IDeepCloneable Clone(Cloner cloner) {
      return new RunCollection(this, cloner);
    }

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

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

    protected override void OnCollectionReset(IEnumerable<IRun> items, IEnumerable<IRun> oldItems) {
      parameterNames.Clear();
      resultNames.Clear();
      dataTypes.Clear();
      foreach (IRun run in items) {
        foreach (KeyValuePair<string, IItem> parameter in run.Parameters)
          AddParameter(parameter.Key, parameter.Value);
        foreach (KeyValuePair<string, IItem> result in run.Results)
          AddResult(result.Key, result.Value);
        run.PropertyChanged += RunOnPropertyChanged;
        RegisterRunParametersEvents(run);
        RegisterRunResultsEvents(run);
      }
      foreach (IRun run in oldItems) {
        run.PropertyChanged -= RunOnPropertyChanged;
        DeregisterRunParametersEvents(run);
        DeregisterRunResultsEvents(run);
      }
      columnNameCache = null;
      OnColumnsChanged();
      OnColumnNamesChanged();
      rowNamesCache = null;
      base.OnCollectionReset(items, oldItems);
      OnRowsChanged();
      OnRowNamesChanged();
      OnReset();
      UpdateFiltering(false);
    }
    protected override void OnItemsAdded(IEnumerable<IRun> items) {
      bool columnsChanged = false;
      foreach (IRun run in items) {
        foreach (KeyValuePair<string, IItem> parameter in run.Parameters)
          columnsChanged |= AddParameter(parameter.Key, parameter.Value);
        foreach (KeyValuePair<string, IItem> result in run.Results)
          columnsChanged |= AddResult(result.Key, result.Value);
        run.PropertyChanged += RunOnPropertyChanged;
        RegisterRunParametersEvents(run);
        RegisterRunResultsEvents(run);
      }
      if (columnsChanged) columnNameCache = null;
      rowNamesCache = null;
      base.OnItemsAdded(items);
      OnReset();
      OnRowsChanged();
      OnRowNamesChanged();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
      UpdateFiltering(false);
    }
    protected override void OnItemsRemoved(IEnumerable<IRun> items) {
      bool columnsChanged = false;
      foreach (IRun run in items) {
        foreach (string parameterName in run.Parameters.Keys)
          columnsChanged |= RemoveParameterName(parameterName);
        foreach (string resultName in run.Results.Keys)
          columnsChanged |= RemoveResultName(resultName);
        run.PropertyChanged -= RunOnPropertyChanged;
        DeregisterRunParametersEvents(run);
        DeregisterRunResultsEvents(run);
      }
      if (columnsChanged) columnNameCache = null;
      rowNamesCache = null;
      base.OnItemsRemoved(items);
      OnReset();
      OnRowsChanged();
      OnRowNamesChanged();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
    }

    private void RunOnPropertyChanged(object sender, PropertyChangedEventArgs e) {
      if (e.PropertyName == "Parameters") {
        RegisterRunParametersEvents((IRun)sender);
      } else if (e.PropertyName == "Results") {
        RegisterRunResultsEvents((IRun)sender);
      }
    }

    private void RegisterRunParametersEvents(IRun run) {
      IObservableDictionary<string, IItem> dict = run.Parameters;
      dict.ItemsAdded += RunOnParameterChanged;
      dict.ItemsRemoved += RunOnParameterRemoved;
      dict.ItemsReplaced += RunOnParameterChanged;
      dict.CollectionReset += RunOnParameterChanged;
    }

    private void RegisterRunResultsEvents(IRun run) {
      IObservableDictionary<string, IItem> dict = run.Results;
      dict.ItemsAdded += RunOnResultChanged;
      dict.ItemsRemoved += RunOnResultRemoved;
      dict.ItemsReplaced += RunOnResultChanged;
      dict.CollectionReset += RunOnResultChanged;
    }

    private void DeregisterRunParametersEvents(IRun run) {
      IObservableDictionary<string, IItem> dict = run.Parameters;
      dict.ItemsAdded -= RunOnParameterChanged;
      dict.ItemsRemoved -= RunOnParameterRemoved;
      dict.ItemsReplaced -= RunOnParameterChanged;
      dict.CollectionReset -= RunOnParameterChanged;
    }

    private void DeregisterRunResultsEvents(IRun run) {
      IObservableDictionary<string, IItem> dict = run.Results;
      dict.ItemsAdded -= RunOnResultChanged;
      dict.ItemsRemoved -= RunOnResultRemoved;
      dict.ItemsReplaced -= RunOnResultChanged;
      dict.CollectionReset -= RunOnResultChanged;
    }

    private void RunOnParameterChanged(object sender, CollectionItemsChangedEventArgs<KeyValuePair<string, IItem>> e) {
      bool columnsChanged = false;
      foreach (var param in e.Items)
        columnsChanged |= AddParameter(param.Key, param.Value);
      foreach (var param in e.OldItems)
        columnsChanged |= RemoveParameterName(param.Key);
      if (columnsChanged) columnNameCache = null;
      OnReset();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
    }

    private void RunOnParameterRemoved(object sender, CollectionItemsChangedEventArgs<KeyValuePair<string, IItem>> e) {
      bool columnsChanged = false;
      foreach (var param in e.Items)
        columnsChanged |= RemoveParameterName(param.Key);
      if (columnsChanged) columnNameCache = null;
      OnReset();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
    }

    private void RunOnResultChanged(object sender, CollectionItemsChangedEventArgs<KeyValuePair<string, IItem>> e) {
      bool columnsChanged = false;
      foreach (var result in e.Items)
        columnsChanged |= AddResult(result.Key, result.Value);
      foreach (var result in e.OldItems)
        columnsChanged |= RemoveResultName(result.Key);
      if (columnsChanged) columnNameCache = null;
      OnReset();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
    }

    private void RunOnResultRemoved(object sender, CollectionItemsChangedEventArgs<KeyValuePair<string, IItem>> e) {
      bool columnsChanged = false;
      foreach (var result in e.Items)
        columnsChanged |= RemoveResultName(result.Key);
      if (columnsChanged) columnNameCache = null;
      OnReset();
      if (columnsChanged) {
        OnColumnsChanged();
        OnColumnNamesChanged();
      }
    }

    private bool AddParameter(string name, IItem value) {
      if (value == null)
        return false;
      if (!parameterNames.Contains(name)) {
        parameterNames.Add(name);
        dataTypes[name] = new HashSet<Type>();
        dataTypes[name].Add(value.GetType());
        return true;
      }
      dataTypes[name].Add(value.GetType());
      return false;
    }
    private bool AddResult(string name, IItem value) {
      if (value == null)
        return false;
      if (!resultNames.Contains(name)) {
        resultNames.Add(name);
        dataTypes[name] = new HashSet<Type>();
        dataTypes[name].Add(value.GetType());
        return true;
      }
      dataTypes[name].Add(value.GetType());
      return false;
    }
    private bool RemoveParameterName(string name) {
      if (!list.Any(x => x.Parameters.ContainsKey(name))) {
        parameterNames.Remove(name);
        return true;
      }
      return false;
    }
    private bool RemoveResultName(string name) {
      if (!list.Any(x => x.Results.ContainsKey(name))) {
        resultNames.Remove(name);
        return true;
      }
      return false;
    }

    public IItem GetValue(int rowIndex, int columnIndex) {
      IRun run = this.list[rowIndex];
      return GetValue(run, columnIndex);
    }

    public IItem GetValue(IRun run, int columnIndex) {
      string name = ((IStringConvertibleMatrix)this).ColumnNames.ElementAt(columnIndex);
      return GetValue(run, name);
    }

    public IItem GetValue(IRun run, string columnName) {
      IItem value = null;
      if (run.Parameters.ContainsKey(columnName))
        value = run.Parameters[columnName];
      else if (run.Results.ContainsKey(columnName))
        value = run.Results[columnName];
      return value;
    }

    #region IStringConvertibleMatrix Members
    [Storable]
    private List<string> parameterNames;
    public IEnumerable<string> ParameterNames {
      get { return this.parameterNames; }
    }
    [Storable]
    private List<string> resultNames;
    public IEnumerable<string> ResultNames {
      get { return this.resultNames; }
    }
    int IStringConvertibleMatrix.Rows {
      get { return this.Count; }
      set { throw new NotSupportedException(); }
    }
    int IStringConvertibleMatrix.Columns {
      get { return parameterNames.Count + resultNames.Count; }
      set { throw new NotSupportedException(); }
    }
    private List<string> columnNameCache;
    IEnumerable<string> IStringConvertibleMatrix.ColumnNames {
      get {
        if (columnNameCache == null) {
          columnNameCache = new List<string>(parameterNames);
          columnNameCache.AddRange(resultNames);
          columnNameCache.Sort();
        }
        return columnNameCache;
      }
      set { throw new NotSupportedException(); }
    }
    private List<string> rowNamesCache;
    IEnumerable<string> IStringConvertibleMatrix.RowNames {
      get {
        if (rowNamesCache == null)
          rowNamesCache = list.Select(x => x.Name).ToList();
        return rowNamesCache;
      }
      set { throw new NotSupportedException(); }
    }
    bool IStringConvertibleMatrix.SortableView {
      get { return true; }
      set { throw new NotSupportedException(); }
    }
    bool IStringConvertibleMatrix.ReadOnly {
      get { return true; }
    }

    string IStringConvertibleMatrix.GetValue(int rowIndex, int columnIndex) {
      IItem value = GetValue(rowIndex, columnIndex);
      if (value == null)
        return string.Empty;
      return value.ToString();
    }

    public event EventHandler<EventArgs<int, int>> ItemChanged;
    protected virtual void OnItemChanged(int rowIndex, int columnIndex) {
      EventHandler<EventArgs<int, int>> handler = ItemChanged;
      if (handler != null) handler(this, new EventArgs<int, int>(rowIndex, columnIndex));
    }
    public event EventHandler Reset;
    protected virtual void OnReset() {
      EventHandler handler = Reset;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler ColumnsChanged;
    protected virtual void OnColumnsChanged() {
      var handler = ColumnsChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler RowsChanged;
    protected virtual void OnRowsChanged() {
      var handler = RowsChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler ColumnNamesChanged;
    protected virtual void OnColumnNamesChanged() {
      EventHandler handler = ColumnNamesChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler RowNamesChanged;
    protected virtual void OnRowNamesChanged() {
      EventHandler handler = RowNamesChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }
    public event EventHandler SortableViewChanged;
    protected virtual void OnSortableViewChanged() {
      EventHandler handler = SortableViewChanged;
      if (handler != null) handler(this, EventArgs.Empty);
    }

    public bool Validate(string value, out string errorMessage) { throw new NotSupportedException(); }
    public bool SetValue(string value, int rowIndex, int columnIndex) { throw new NotSupportedException(); }
    #endregion

    #region Filtering
    private void UpdateFiltering(bool reset) {
      if (reset)
        list.ForEach(r => r.Visible = true);
      foreach (IRunCollectionConstraint constraint in this.constraints)
        constraint.Check();
    }

    private void RegisterConstraintsEvents() {
      constraints.ItemsAdded += new CollectionItemsChangedEventHandler<IRunCollectionConstraint>(Constraints_ItemsAdded);
      constraints.ItemsRemoved += new CollectionItemsChangedEventHandler<IRunCollectionConstraint>(Constraints_ItemsRemoved);
      constraints.CollectionReset += new CollectionItemsChangedEventHandler<IRunCollectionConstraint>(Constraints_CollectionReset);
    }

    private void RegisterConstraintEvents(IEnumerable<IRunCollectionConstraint> constraints) {
      foreach (IRunCollectionConstraint constraint in constraints) {
        constraint.ActiveChanged += new EventHandler(Constraint_ActiveChanged);
        constraint.ConstrainedValueChanged += new EventHandler(Constraint_ConstrainedValueChanged);
        constraint.ConstraintOperationChanged += new EventHandler(Constraint_ConstraintOperationChanged);
        constraint.ConstraintDataChanged += new EventHandler(Constraint_ConstraintDataChanged);
      }
    }
    private void DeregisterConstraintEvents(IEnumerable<IRunCollectionConstraint> constraints) {
      foreach (IRunCollectionConstraint constraint in constraints) {
        constraint.ActiveChanged -= new EventHandler(Constraint_ActiveChanged);
        constraint.ConstrainedValueChanged -= new EventHandler(Constraint_ConstrainedValueChanged);
        constraint.ConstraintOperationChanged -= new EventHandler(Constraint_ConstraintOperationChanged);
        constraint.ConstraintDataChanged -= new EventHandler(Constraint_ConstraintDataChanged);
      }
    }

    protected virtual void Constraints_CollectionReset(object sender, CollectionItemsChangedEventArgs<IRunCollectionConstraint> e) {
      DeregisterConstraintEvents(e.OldItems);
      RegisterConstraintEvents(e.Items);
      this.UpdateFiltering(true);
    }
    protected virtual void Constraints_ItemsAdded(object sender, CollectionItemsChangedEventArgs<IRunCollectionConstraint> e) {
      RegisterConstraintEvents(e.Items);
      foreach (IRunCollectionConstraint constraint in e.Items)
        constraint.ConstrainedValue = this;
      this.UpdateFiltering(false);
    }
    protected virtual void Constraints_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<IRunCollectionConstraint> e) {
      DeregisterConstraintEvents(e.Items);
      this.UpdateFiltering(true);
    }
    protected virtual void Constraint_ActiveChanged(object sender, EventArgs e) {
      IRunCollectionConstraint constraint = (IRunCollectionConstraint)sender;
      this.UpdateFiltering(!constraint.Active);
    }
    protected virtual void Constraint_ConstrainedValueChanged(object sender, EventArgs e) {
      //mkommend: this method is intentionally left empty, because the constrainedValue is set in the ItemsAdded method
    }
    protected virtual void Constraint_ConstraintOperationChanged(object sender, EventArgs e) {
      IRunCollectionConstraint constraint = (IRunCollectionConstraint)sender;
      if (constraint.Active) {
        var oldUpdateRuns = UpdateOfRunsInProgress;
        try {
          UpdateOfRunsInProgress = true;
          UpdateFiltering(true);
        } finally { UpdateOfRunsInProgress = oldUpdateRuns; }
      }
    }
    protected virtual void Constraint_ConstraintDataChanged(object sender, EventArgs e) {
      IRunCollectionConstraint constraint = (IRunCollectionConstraint)sender;
      if (constraint.Active) {
        var oldUpdateRuns = UpdateOfRunsInProgress;
        try {
          UpdateOfRunsInProgress = true;
          UpdateFiltering(true);
        } finally { UpdateOfRunsInProgress = oldUpdateRuns; }
      }
    }
    #endregion

    #region Modification
    public void Modify() {
      var runs = this.ToList();
      var selectedRuns = runs.Where(r => r.Visible).ToList();
      int nSelected = selectedRuns.Count;
      if (nSelected > 0) {
        foreach (var modifier in Modifiers.CheckedItems)
          modifier.Value.Modify(selectedRuns);
        if (nSelected != selectedRuns.Count || HaveDifferentOrder(selectedRuns, runs.Where(r => r.Visible))) {
          Clear();
          AddRange(ReplaceVisibleRuns(runs, selectedRuns));
        } else if (runs.Count > 0) {
          OnCollectionReset(this, runs);
        }
      }
    }

    private static IEnumerable<IRun> ReplaceVisibleRuns(IEnumerable<IRun> runs, IEnumerable<IRun> visibleRuns) {
      var newRuns = new List<IRun>();
      var runIt = runs.GetEnumerator();
      var visibleRunIt = visibleRuns.GetEnumerator();
      while (runIt.MoveNext()) {
        if (runIt.Current != null && !runIt.Current.Visible)
          newRuns.Add(runIt.Current);
        else if (visibleRunIt.MoveNext())
          newRuns.Add(visibleRunIt.Current);
      }
      while (visibleRunIt.MoveNext())
        newRuns.Add(visibleRunIt.Current);
      return newRuns;
    }

    private static bool HaveDifferentOrder(IEnumerable<IRun> l1, IEnumerable<IRun> l2) {
      return l1.Zip(l2, (r1, r2) => r1 != r2).Any();
    }
    #endregion
  }
}