#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2010 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.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using HeuristicLab.MainForm;
using HeuristicLab.Core;
using HeuristicLab.Core.Views;
using Netron.Diagramming.Core;
using HeuristicLab.Parameters;
using HeuristicLab.MainForm.WindowsForms;
using HeuristicLab.Collections;
using System.Diagnostics;
using System.Threading;

namespace HeuristicLab.Operators.Views.GraphVisualization {
  [View("GraphVisualizationInfo View")]
  [Content(typeof(GraphVisualizationInfo), false)]
  public partial class GraphVisualizationInfoView : ContentView {
    private BidirectionalLookup<IOperatorShapeInfo, IShape> shapeInfoShapeMapping;
    private BidirectionalLookup<IOperatorShapeInfo, INotifyObservableDictionaryItemsChanged<string, IOperatorShapeInfo>> shapeInfoConnectionsMapping;
    private BidirectionalLookup<IConnection, KeyValuePair<IConnector, IConnector>> connectionConnectorsMapping;

    private bool causedUpdateOfShapeInfo;
    public GraphVisualizationInfoView() {
      InitializeComponent();
      this.causedUpdateOfShapeInfo = false;
      this.shapeInfoShapeMapping = new BidirectionalLookup<IOperatorShapeInfo, IShape>();
      this.shapeInfoConnectionsMapping = new BidirectionalLookup<IOperatorShapeInfo, INotifyObservableDictionaryItemsChanged<string, IOperatorShapeInfo>>();
      this.connectionConnectorsMapping = new BidirectionalLookup<IConnection, KeyValuePair<IConnector, IConnector>>();
    }

    public GraphVisualizationInfoView(GraphVisualizationInfo content)
      : this() {
      this.Content = content;
    }

    public IController Controller {
      get { return this.graphVisualization.Controller; }
    }

    public new GraphVisualizationInfo Content {
      get { return (GraphVisualizationInfo)base.Content; }
      set { base.Content = value; }
    }

    protected override void OnContentChanged() {
      base.OnContentChanged();
      this.UpdateContent();
    }

    private void UpdateContent() {
      foreach (IOperatorShapeInfo shapeInfo in this.shapeInfoShapeMapping.FirstValues)
        this.RemoveShapeInfo(shapeInfo);

      this.shapeInfoShapeMapping.Clear();
      this.shapeInfoConnectionsMapping.Clear();
      this.connectionConnectorsMapping.Clear();

      foreach (IOperatorShapeInfo shapeInfo in this.Content.OperatorShapeInfos)
        if (!this.shapeInfoShapeMapping.ContainsFirst(shapeInfo))
          this.AddShapeInfo(shapeInfo);

      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> connection in this.Content.Connections)
        this.AddConnection(connection.Key.Key, connection.Key.Value, connection.Value);

      this.UpdateLayoutRoot();
    }

    private void UpdateLayoutRoot() {
      IOperatorShapeInfo shapeInfo = this.Content.InitialShape;
      if (shapeInfo != null)
        this.graphVisualization.Controller.Model.LayoutRoot = this.shapeInfoShapeMapping.GetByFirst(shapeInfo);
      else
        this.graphVisualization.Controller.Model.LayoutRoot = null;
    }

    private void VisualizationInfo_InitialShapeChanged(object sender, EventArgs e) {
      this.UpdateLayoutRoot();
    }

    protected override void RegisterContentEvents() {
      base.RegisterContentEvents();
      this.Content.InitialShapeChanged += new EventHandler(VisualizationInfo_InitialShapeChanged);
      this.Content.ObserveableShapeInfos.ItemsAdded += new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_ItemsAdded);
      this.Content.ObserveableShapeInfos.ItemsRemoved += new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_ItemsRemoved);
      this.Content.ObserveableShapeInfos.CollectionReset += new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_CollectionReset);

      this.Content.ObservableConnections.ItemsAdded += new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsAdded);
      this.Content.ObservableConnections.ItemsRemoved += new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsRemoved);
      this.Content.ObservableConnections.ItemsReplaced += new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsReplaced);
      this.Content.ObservableConnections.CollectionReset += new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_CollectionReset);
    }

    protected override void DeregisterContentEvents() {
      base.DeregisterContentEvents();
      this.Content.InitialShapeChanged -= new EventHandler(VisualizationInfo_InitialShapeChanged);
      this.Content.ObserveableShapeInfos.ItemsAdded -= new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_ItemsAdded);
      this.Content.ObserveableShapeInfos.ItemsRemoved -= new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_ItemsRemoved);
      this.Content.ObserveableShapeInfos.CollectionReset -= new HeuristicLab.Collections.CollectionItemsChangedEventHandler<IOperatorShapeInfo>(ShapeInfos_CollectionReset);

      this.Content.ObservableConnections.ItemsAdded -= new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsAdded);
      this.Content.ObservableConnections.ItemsRemoved -= new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsRemoved);
      this.Content.ObservableConnections.ItemsReplaced -= new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_ItemsReplaced);
      this.Content.ObservableConnections.CollectionReset -= new CollectionItemsChangedEventHandler<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>>(Connections_CollectionReset);
    }

    private void ShapeInfos_CollectionReset(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IOperatorShapeInfo> e) {
      foreach (IOperatorShapeInfo shapeInfo in e.OldItems)
        this.RemoveShapeInfo(shapeInfo);
      foreach (IOperatorShapeInfo shapeInfo in e.Items)
        this.AddShapeInfo(shapeInfo);
    }

    private void ShapeInfos_ItemsAdded(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IOperatorShapeInfo> e) {
      foreach (IOperatorShapeInfo shapeInfo in e.Items)
        this.AddShapeInfo(shapeInfo);
    }

    private void ShapeInfos_ItemsRemoved(object sender, HeuristicLab.Collections.CollectionItemsChangedEventArgs<IOperatorShapeInfo> e) {
      foreach (IOperatorShapeInfo shapeInfo in e.Items)
        this.RemoveShapeInfo(shapeInfo);
    }

    private void AddShapeInfo(IOperatorShapeInfo shapeInfo) {
      this.RegisterShapeInfoEvents(shapeInfo);

      IShape shape = shapeInfo.CreateShape();
      shape.OnEntityChange += new EventHandler<EntityEventArgs>(shape_OnEntityChange);
      shape.OnMouseEnter += new EventHandler<EntityMouseEventArgs>(shape_OnMouseEnter);
      shape.OnMouseLeave += new EventHandler<EntityMouseEventArgs>(shape_OnMouseLeave);
      this.shapeInfoShapeMapping.Add(shapeInfo, shape);

      this.graphVisualization.Controller.Model.AddShape(shape);
      this.graphVisualization.Invalidate();
    }

    private void RemoveShapeInfo(IOperatorShapeInfo shapeInfo) {
      this.DeregisterShapeInfoEvents(shapeInfo);
      IShape shape = this.shapeInfoShapeMapping.GetByFirst(shapeInfo);
      shape.OnEntityChange -= new EventHandler<EntityEventArgs>(shape_OnEntityChange);
      shape.OnMouseEnter -= new EventHandler<EntityMouseEventArgs>(shape_OnMouseEnter);
      shape.OnMouseLeave -= new EventHandler<EntityMouseEventArgs>(shape_OnMouseLeave);

      IConnection connection;
      foreach (IConnector connector in shape.Connectors) {
        connection = this.GetConnection(shapeInfo, connector.Name);
        this.RemoveConnection(connection);
      }

      this.shapeInfoShapeMapping.RemoveByFirst(shapeInfo);
      this.shapeInfoConnectionsMapping.RemoveByFirst(shapeInfo);

      if (this.graphVisualization.Controller.Model.Shapes.Contains(shape)) {
        this.graphVisualization.Controller.Model.RemoveShape(shape);
      }
      this.graphVisualization.Invalidate();
    }

    private void RegisterShapeInfoEvents(IShapeInfo shapeInfo) {
      shapeInfo.Changed += new EventHandler(shapeInfo_Changed);
    }

    private void DeregisterShapeInfoEvents(IShapeInfo shapeInfo) {
      shapeInfo.Changed -= new EventHandler(shapeInfo_Changed);
    }

    private void Connections_CollectionReset(object sender, CollectionItemsChangedEventArgs<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>> e) {
      IConnection connection;
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items) {
        connection = this.GetConnection(pair.Key.Key, pair.Key.Value);
        this.RemoveConnection(connection);
      }
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items)
        this.AddConnection(pair.Key.Key, pair.Key.Value, pair.Value);
    }

    private void Connections_ItemsReplaced(object sender, CollectionItemsChangedEventArgs<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>> e) {
      IConnection connection;
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items) {
        connection = this.GetConnection(pair.Key.Key, pair.Key.Value);
        this.RemoveConnection(connection);
      }
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items)
        this.AddConnection(pair.Key.Key, pair.Key.Value, pair.Value);
    }

    private void Connections_ItemsAdded(object sender, CollectionItemsChangedEventArgs<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>> e) {
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items)
        this.AddConnection(pair.Key.Key, pair.Key.Value, pair.Value);
    }

    private void Connections_ItemsRemoved(object sender, CollectionItemsChangedEventArgs<KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo>> e) {
      IConnection connection;
      foreach (KeyValuePair<KeyValuePair<IOperatorShapeInfo, string>, IOperatorShapeInfo> pair in e.Items) {
        connection = this.GetConnection(pair.Key.Key, pair.Key.Value);
        this.RemoveConnection(connection);
      }
    }

    private void AddConnection(IOperatorShapeInfo shapeInfoFrom, string connectorName, IOperatorShapeInfo shapeInfoTo) {
      IShape shapeFrom = this.shapeInfoShapeMapping.GetByFirst(shapeInfoFrom);
      IShape shapeTo = this.shapeInfoShapeMapping.GetByFirst(shapeInfoTo);

      IConnector connectorFrom = shapeFrom.Connectors.Where(c => c.Name == connectorName).First();
      IConnector connectorTo = shapeTo.Connectors.Where(c => c.Name == "Predecessor").FirstOrDefault();
      KeyValuePair<IConnector, IConnector> connectorPair = new KeyValuePair<IConnector, IConnector>(connectorFrom, connectorTo);
      if (!this.connectionConnectorsMapping.ContainsSecond(connectorPair)) {
        IConnection connection = Factory.CreateConnection(connectorFrom, connectorTo);
        this.connectionConnectorsMapping.Add(connection, connectorPair);
        this.graphVisualization.Controller.Model.AddConnection(connection);
        this.graphVisualization.Invalidate();
      }
    }

    private IConnection GetConnection(IOperatorShapeInfo shapeInfoFrom, string connectorName) {
      IShape shape = this.shapeInfoShapeMapping.GetByFirst(shapeInfoFrom);
      IConnector connector = shape.Connectors.Where(c => c.Name == connectorName).First();

      if (!this.connectionConnectorsMapping.SecondValues.Any(p => p.Key == connector))
        return null;

      KeyValuePair<IConnector, IConnector> connectorPair = this.connectionConnectorsMapping.SecondValues.Where(p => p.Key == connector).FirstOrDefault();
      return this.connectionConnectorsMapping.GetBySecond(connectorPair);
    }

    private void ChangeConnection(IOperatorShapeInfo shapeInfoFrom, string connectorName, IOperatorShapeInfo shapeInfoTo) {
      IConnection connection = this.GetConnection(shapeInfoFrom, connectorName);
      IShape shapeTo = this.shapeInfoShapeMapping.GetByFirst(shapeInfoFrom);
      IConnector connectorTo = shapeTo.Connectors.Where(c => c.Name == "Predecessor").First();

      connection.To.DetachFromParent();
      connection.To.AttachTo(connectorTo);
      this.graphVisualization.Invalidate();
    }

    private void RemoveConnection(IConnection connection) {
      if (connection == null)
        return;

      if (connection.From.AttachedTo != null)
        connection.From.DetachFromParent();
      if (connection.To.AttachedTo != null)
        connection.To.DetachFromParent();

      if (this.connectionConnectorsMapping.ContainsFirst(connection))
        this.connectionConnectorsMapping.RemoveByFirst(connection);
      if (this.graphVisualization.Controller.Model.Connections.Contains(connection))
        this.graphVisualization.Controller.Model.Remove(connection);
      this.graphVisualization.Invalidate();
    }


    private void shapeInfo_Changed(object sender, EventArgs e) {
      if (this.causedUpdateOfShapeInfo)
        return;

      this.causedUpdateOfShapeInfo = true;
      IOperatorShapeInfo shapeInfo = (IOperatorShapeInfo)sender;
      IShape shape = this.shapeInfoShapeMapping.GetByFirst(shapeInfo);
      shapeInfo.UpdateShape(shape);
      shape.Invalidate();
      this.causedUpdateOfShapeInfo = false;
    }

    private Cursor oldCursor;
    private void shape_OnMouseEnter(object sender, EntityMouseEventArgs e) {
      this.oldCursor = this.Cursor;
      this.Controller.View.CurrentCursor = CursorPalette.Move;
    }

    private void shape_OnMouseLeave(object sender, EntityMouseEventArgs e) {
      this.Controller.View.CurrentCursor = this.oldCursor;
      this.oldCursor = null;
    }

    private void shape_OnEntityChange(object sender, EntityEventArgs e) {
      if (this.causedUpdateOfShapeInfo)
        return;

      this.causedUpdateOfShapeInfo = true;
      IShape shape = e.Entity as IShape;
      IOperatorShapeInfo shapeInfo = this.shapeInfoShapeMapping.GetBySecond(shape);
      shapeInfo.Location = shape.Location;

      OperatorShape operatorShape = shape as OperatorShape;
      if (operatorShape != null)
        shapeInfo.Collapsed = operatorShape.Collapsed;
      
      this.graphVisualization.Invalidate();
      this.causedUpdateOfShapeInfo = false;
    }

    private void graphVisualization_OnEntityAdded(object sender, EntityEventArgs e) {
      IConnection connection = e.Entity as IConnection;
      if (connection != null && !this.connectionConnectorsMapping.ContainsFirst(connection)) {
        IConnector connectorFrom = connection.From.AttachedTo;
        IConnector connectorTo = connection.To.AttachedTo;
        this.RemoveConnection(connection); //is added again by the model events

        if (connectorFrom != null && connectorTo != null && connectorFrom.Name != "Predecessor") {
          IShape shapeFrom = (IShape)connectorFrom.Parent;
          IShape shapeTo = (IShape)connectorTo.Parent;
          IOperatorShapeInfo shapeInfoFrom = this.shapeInfoShapeMapping.GetBySecond(shapeFrom);
          IOperatorShapeInfo shapeInfoTo = this.shapeInfoShapeMapping.GetBySecond(shapeTo);
          string connectorName = connectorFrom.Name;

          this.Content.AddConnection(shapeInfoFrom, connectorName, shapeInfoTo);
        }
      }
    }

    private void graphVisualization_OnEntityRemoved(object sender, EntityEventArgs e) {
      IShape shape = e.Entity as IShape;
      if (shape != null && this.shapeInfoShapeMapping.ContainsSecond(shape)) {
        IOperatorShapeInfo shapeInfo = this.shapeInfoShapeMapping.GetBySecond(shape);
        this.Content.RemoveShapeInfo(shapeInfo);
      }

      IConnection connection = e.Entity as IConnection;
      if (connection != null && this.connectionConnectorsMapping.ContainsFirst(connection)) {
        IShape parentShape = (IShape)connection.From.AttachedTo.Parent;
        IOperatorShapeInfo shapeInfo = this.shapeInfoShapeMapping.GetBySecond(parentShape);
        string connectorName = connection.From.AttachedTo.Name;

        this.Content.RemoveConnection(shapeInfo, connectorName);
      }
    }

    internal void RelayoutGraph() {
      if (this.shapeInfoShapeMapping.Count > 0
        && this.connectionConnectorsMapping.Count > 0
        && this.Content.InitialShape != null) { //otherwise the layout does not work
        string layoutName = "Standard TreeLayout";
        this.graphVisualization.Controller.RunActivity(layoutName);
        this.graphVisualization.Invalidate();

        //fix to avoid negative shape positions after layouting
        Thread.Sleep(100);
        int minX = this.graphVisualization.Controller.Model.Shapes.Min(s => s.Location.X);
        int shiftX = minX < 0 ? Math.Abs(minX) + 50 : 0;
        int minY = this.graphVisualization.Controller.Model.Shapes.Min(s => s.Location.Y);
        int shiftY = minY < 0 ? Math.Abs(minY) + 50 : 0;
        if (minX < 0 || minY < 0) {
          foreach (IShape s in this.Controller.Model.Shapes)
            s.MoveBy(new Point(shiftX, shiftY));
        }
      }
    }
  }
}