source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/Charts/Navigation/AxisCursorGraph.cs @ 12747

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Controls;
using System.Windows.Shapes;
using System.Windows.Input;
using System.Windows;
using System.Windows.Media;
using System.Windows.Data;
using Microsoft.Research.DynamicDataDisplay.Common;

namespace Microsoft.Research.DynamicDataDisplay.Charts.Navigation
{
  /// <summary>
  /// Adds to ChartPlotter two lines upon axes, showing current cursor position.
  /// </summary>
  public class AxisCursorGraph : DependencyObject, IPlotterElement
  {
    static AxisCursorGraph()
    {
      Line.StrokeProperty.AddOwner(typeof(AxisCursorGraph), new FrameworkPropertyMetadata(Brushes.Red));
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="AxisCursorGraph"/> class.
    /// </summary>
    public AxisCursorGraph() { }

    #region ShowVerticalLine property

    /// <summary>
    /// Gets or sets a value indicating whether to show line upon vertical axis.
    /// </summary>
    /// <value><c>true</c> if line upon vertical axis is shown; otherwise, <c>false</c>.</value>
    public bool ShowVerticalLine
    {
      get { return (bool)GetValue(ShowVerticalLineProperty); }
      set { SetValue(ShowVerticalLineProperty, value); }
    }

    /// <summary>
    /// Identifies ShowVerticalLine dependency property.
    /// </summary>
    public static readonly DependencyProperty ShowVerticalLineProperty = DependencyProperty.Register(
      "ShowVerticalLine",
      typeof(bool),
      typeof(AxisCursorGraph),
      new FrameworkPropertyMetadata(true, OnShowLinePropertyChanged));

    private static void OnShowLinePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
      AxisCursorGraph graph = (AxisCursorGraph)d;
      graph.UpdateUIRepresentation();
    }

    #endregion

    #region ShowHorizontalLine property

    /// <summary>
    /// Gets or sets a value indicating whether to show line upon horizontal axis.
    /// </summary>
    /// <value><c>true</c> if lien upon horizontal axis is shown; otherwise, <c>false</c>.</value>
    public bool ShowHorizontalLine
    {
      get { return (bool)GetValue(ShowHorizontalLineProperty); }
      set { SetValue(ShowHorizontalLineProperty, value); }
    }

    public static readonly DependencyProperty ShowHorizontalLineProperty = DependencyProperty.Register(
      "ShowHorizontalLine",
      typeof(bool),
      typeof(AxisCursorGraph),
      new FrameworkPropertyMetadata(true, OnShowLinePropertyChanged));

    #endregion

    #region IPlotterElement Members

    private Line leftLine;
    private Line bottomLine;
    private Canvas leftCanvas;
    private Canvas bottomCanvas;

    private Plotter2D plotter;
    void IPlotterElement.OnPlotterAttached(Plotter plotter)
    {
      this.plotter = (Plotter2D)plotter;

      this.plotter.Viewport.PropertyChanged += Viewport_PropertyChanged;

      var parent = plotter.MainGrid;
      parent.MouseMove += parent_MouseMove;
      parent.MouseEnter += parent_MouseEnter;
      parent.MouseLeave += parent_MouseLeave;

      Style lineStyle = new Style(typeof(Line));
      AddBindingSetter(lineStyle, Line.StrokeProperty);
      AddBindingSetter(lineStyle, Line.StrokeThicknessProperty);

      leftCanvas = new Canvas();
      Grid.SetRow(leftCanvas, 1);
      Grid.SetColumn(leftCanvas, 0);
      leftLine = new Line { Style = lineStyle, IsHitTestVisible = false };
      leftCanvas.Children.Add(leftLine);
      parent.Children.Add(leftCanvas);

      bottomCanvas = new Canvas();
      Grid.SetRow(bottomCanvas, 2);
      Grid.SetColumn(bottomCanvas, 1);
      bottomLine = new Line { Style = lineStyle, IsHitTestVisible = false };
      bottomCanvas.Children.Add(bottomLine);
      parent.Children.Add(bottomCanvas);
    }

    private void AddBindingSetter(Style style, DependencyProperty property)
    {
      style.Setters.Add(new Setter(property,
        new Binding
        {
          Path = new PropertyPath(property.Name),
          Source = this
        }));
    }

    void Viewport_PropertyChanged(object sender, ExtendedPropertyChangedEventArgs e)
    {
      UpdateUIRepresentation();
    }

    private void UpdateUIRepresentation()
    {
      if (plotter == null) return;

      var transform = plotter.Viewport.Transform;
      DataRect visible = plotter.Viewport.Visible;
      Rect output = plotter.Viewport.Output;

      Point mousePos = Mouse.GetPosition(plotter.CentralGrid);

      if (ShowVerticalLine)
      {
        double y = mousePos.Y;
        if (output.Top <= y && y <= output.Bottom)
        {
          leftLine.Visibility = Visibility.Visible;
          leftLine.X1 = 0;
          leftLine.X2 = plotter.LeftPanel.ActualWidth;

          leftLine.Y1 = leftLine.Y2 = y;
        }
        else
        {
          leftLine.Visibility = Visibility.Collapsed;
        }
      }
      else
      {
        leftLine.Visibility = Visibility.Collapsed;
      }

      if (ShowHorizontalLine)
      {
        double x = mousePos.X;
        if (output.Left <= x && x <= output.Right)
        {
          bottomLine.Visibility = Visibility.Visible;
          bottomLine.Y1 = 0;
          bottomLine.Y2 = plotter.BottomPanel.ActualHeight;

          bottomLine.X1 = bottomLine.X2 = x;
        }
        else
        {
          bottomLine.Visibility = Visibility.Collapsed;
        }
      }
      else
      {
        bottomLine.Visibility = Visibility.Collapsed;
      }
    }

    void parent_MouseLeave(object sender, MouseEventArgs e)
    {
      UpdateUIRepresentation();
    }

    void parent_MouseEnter(object sender, MouseEventArgs e)
    {
      UpdateUIRepresentation();
    }

    void parent_MouseMove(object sender, MouseEventArgs e)
    {
      UpdateUIRepresentation();
    }

    void IPlotterElement.OnPlotterDetaching(Plotter plotter)
    {
      this.plotter.Viewport.PropertyChanged -= Viewport_PropertyChanged;

      var parent = plotter.MainGrid;
      parent.MouseMove -= parent_MouseMove;
      parent.MouseEnter -= parent_MouseEnter;
      parent.MouseLeave -= parent_MouseLeave;

      parent.Children.Remove(leftCanvas);
      parent.Children.Remove(bottomCanvas);

      this.plotter = null;
    }

    Plotter IPlotterElement.Plotter
    {
      get { return plotter; }
    }

    #endregion
  }
}