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

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Input;
using System.Windows.Controls;
using System.Windows.Media;
using Microsoft.Research.DynamicDataDisplay.Charts.Axes;
using Microsoft.Research.DynamicDataDisplay.Common.Auxiliary;
using System.Diagnostics;

namespace Microsoft.Research.DynamicDataDisplay.Charts.Navigation
{
  public class AxisNavigation : DependencyObject, IPlotterElement
  {
    public AxisPlacement Placement
    {
      get { return (AxisPlacement)GetValue(PlacementProperty); }
      set { SetValue(PlacementProperty, value); }
    }

    public static readonly DependencyProperty PlacementProperty = DependencyProperty.Register(
      "Placement",
      typeof(AxisPlacement),
      typeof(AxisNavigation),
      new FrameworkPropertyMetadata(AxisPlacement.Left, OnPlacementChanged));

    private static void OnPlacementChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
      AxisNavigation navigation = (AxisNavigation)d;
      navigation.OnPlacementChanged();
    }

    private Panel listeningPanel;
    protected Panel ListeningPanel
    {
      get { return listeningPanel; }
    }

    private void OnPlacementChanged()
    {
      SetListeningPanel();
    }

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

      AxisPlacement placement = Placement;
      switch (placement)
      {
        case AxisPlacement.Left:
          listeningPanel = plotter.LeftPanel;
          break;
        case AxisPlacement.Right:
          listeningPanel = plotter.RightPanel;
          break;
        case AxisPlacement.Top:
          listeningPanel = plotter.TopPanel;
          break;
        case AxisPlacement.Bottom:
          listeningPanel = plotter.BottomPanel;
          break;
        default:
          break;
      }
    }

    private CoordinateTransform Transform
    {
      get { return plotter.Viewport.Transform; }
    }

    private Panel hostPanel;

    #region IPlotterElement Members

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

      hostPanel = plotter.MainGrid;

      //hostPanel.Background = Brushes.Pink;

      SetListeningPanel();

      if (hostPanel != null)
      {
        hostPanel.MouseLeftButtonUp += OnMouseLeftButtonUp;
        hostPanel.MouseLeftButtonDown += OnMouseLeftButtonDown;
        hostPanel.MouseMove += OnMouseMove;
        hostPanel.MouseWheel += OnMouseWheel;

        hostPanel.MouseRightButtonDown += OnMouseRightButtonDown;
        hostPanel.MouseRightButtonUp += OnMouseRightButtonUp;
        hostPanel.LostFocus += OnLostFocus;
      }
    }

    private void OnLostFocus(object sender, RoutedEventArgs e)
    {
      //Debug.WriteLine("Lost Focus");
      RevertChanges();
      rmbPressed = false;
      lmbPressed = false;

      e.Handled = true;
    }

    #region Right button down

    DataRect rmbDragStartRect;
    private void OnMouseRightButtonDown(object sender, MouseButtonEventArgs e)
    {
      OnMouseRightButtonDown(e);
    }

    protected virtual void OnMouseRightButtonDown(MouseButtonEventArgs e)
    {
      rmbInitialPosition = e.GetPosition(listeningPanel);

      var foundActivePlotter = UpdateActivePlotter(e);
      if (foundActivePlotter)
      {
        rmbPressed = true;
        dragStartInViewport = rmbInitialPosition.ScreenToViewport(activePlotter.Transform);
        rmbDragStartRect = activePlotter.Visible;

        listeningPanel.Background = fillBrush;
        listeningPanel.CaptureMouse();

        //e.Handled = true;
      }
    }

    #endregion

    #region Right button up

    private void OnMouseRightButtonUp(object sender, MouseButtonEventArgs e)
    {
      OnMouseRightButtonUp(e);
    }

    protected virtual void OnMouseRightButtonUp(MouseButtonEventArgs e)
    {
      if (rmbPressed)
      {
        rmbPressed = false;
        RevertChanges();

        //e.Handled = true;
      }
    }

    #endregion

    private void RevertChanges()
    {
      listeningPanel.ClearValue(Panel.CursorProperty);
      listeningPanel.Background = Brushes.Transparent;
      listeningPanel.ReleaseMouseCapture();
    }

    private const double wheelZoomSpeed = 1.2;
    private void OnMouseWheel(object sender, MouseWheelEventArgs e)
    {
      Point mousePos = e.GetPosition(listeningPanel);

      Rect listeningPanelBounds = new Rect(listeningPanel.RenderSize);
      if (!listeningPanelBounds.Contains(mousePos))
        return;

      var foundActivePlotter = UpdateActivePlotter(e);
      if (!foundActivePlotter) return;

      int delta = -e.Delta;

      Point zoomTo = mousePos.ScreenToViewport(activePlotter.Transform);

      double zoomSpeed = Math.Abs(delta / Mouse.MouseWheelDeltaForOneLine);
      zoomSpeed *= wheelZoomSpeed;
      if (delta < 0)
      {
        zoomSpeed = 1 / zoomSpeed;
      }

      DataRect visible = activePlotter.Viewport.Visible.Zoom(zoomTo, zoomSpeed);
      DataRect oldVisible = activePlotter.Viewport.Visible;
      if (Placement.IsBottomOrTop())
      {
        visible.YMin = oldVisible.YMin;
        visible.Height = oldVisible.Height;
      }
      else
      {
        visible.XMin = oldVisible.XMin;
        visible.Width = oldVisible.Width;
      }

      activePlotter.Viewport.SetChangeType(Placement.GetZoomChangeType());
      activePlotter.Viewport.Visible = visible;
      activePlotter.Viewport.SetChangeType(ChangeType.None);

      e.Handled = true;
    }

    private const int RmbZoomScale = 200;
    private void OnMouseMove(object sender, MouseEventArgs e)
    {
      if (lmbPressed)
      {
        // panning: 
        if (e.LeftButton == MouseButtonState.Released)
        {
          lmbPressed = false;
          RevertChanges();
          return;
        }

        Point screenMousePos = e.GetPosition(listeningPanel);
        Point dataMousePos = screenMousePos.ScreenToViewport(activePlotter.Transform);
        DataRect visible = activePlotter.Viewport.Visible;
        double delta;
        if (Placement.IsBottomOrTop())
        {
          delta = (dataMousePos - dragStartInViewport).X;
          visible.XMin -= delta;
        }
        else
        {
          delta = (dataMousePos - dragStartInViewport).Y;
          visible.YMin -= delta;
        }

        if (screenMousePos != lmbInitialPosition)
        {
          listeningPanel.Cursor = Placement.IsBottomOrTop() ? Cursors.ScrollWE : Cursors.ScrollNS;
        }

        activePlotter.Viewport.SetChangeType(Placement.GetPanChangeType());
        activePlotter.Viewport.Visible = visible;
        activePlotter.Viewport.SetChangeType();

        e.Handled = true;
      }
      else if (rmbPressed)
      {
        // one direction zooming:
        if (e.RightButton == MouseButtonState.Released)
        {
          rmbPressed = false;
          RevertChanges();
          return;
        }

        Point screenMousePos = e.GetPosition(listeningPanel);
        DataRect visible = activePlotter.Viewport.Visible;
        double delta;

        bool isHorizontal = Placement.IsBottomOrTop();
        if (isHorizontal)
        {
          delta = (screenMousePos - rmbInitialPosition).X;
        }
        else
        {
          delta = (screenMousePos - rmbInitialPosition).Y;
        }

        if (delta < 0)
          delta = 1 / Math.Exp(-delta / RmbZoomScale);
        else
          delta = Math.Exp(delta / RmbZoomScale);

        Point center = dragStartInViewport;

        if (isHorizontal)
        {
          visible = rmbDragStartRect.ZoomX(center, delta);
        }
        else
        {
          visible = rmbDragStartRect.ZoomY(center, delta);
        }

        if (screenMousePos != lmbInitialPosition)
        {
          listeningPanel.Cursor = Placement.IsBottomOrTop() ? Cursors.ScrollWE : Cursors.ScrollNS;
        }

        activePlotter.Viewport.SetChangeType(Placement.GetZoomChangeType());
        activePlotter.Viewport.Visible = visible;
        activePlotter.Viewport.SetChangeType();

        //e.Handled = true;
      }
    }

    private Point lmbInitialPosition;
    protected Point LmbInitialPosition
    {
      get { return lmbInitialPosition; }
    }

    private Point rmbInitialPosition;
    private readonly SolidColorBrush fillBrush = new SolidColorBrush(Color.FromRgb(255, 228, 209)).MakeTransparent(0.2);
    private bool lmbPressed;
    private bool rmbPressed;
    private Point dragStartInViewport;
    private Plotter2D activePlotter;

    #region Left button down

    private void OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
      OnMouseLeftButtonDown(e);
    }

    protected virtual void OnMouseLeftButtonDown(MouseButtonEventArgs e)
    {
      lmbInitialPosition = e.GetPosition(listeningPanel);

      var foundActivePlotter = UpdateActivePlotter(e);
      if (foundActivePlotter)
      {
        lmbPressed = true;
        dragStartInViewport = lmbInitialPosition.ScreenToViewport(activePlotter.Transform);

        listeningPanel.Background = fillBrush;
        listeningPanel.CaptureMouse();

        e.Handled = true;
      }
    }

    #endregion

    private bool UpdateActivePlotter(MouseEventArgs e)
    {
      var axes = listeningPanel.Children.OfType<GeneralAxis>();

      foreach (var axis in axes)
      {
        var positionInAxis = e.GetPosition(axis);
        Rect axisBounds = new Rect(axis.RenderSize);
        if (axisBounds.Contains(positionInAxis))
        {
          activePlotter = axis.Plotter;

          return true;
        }
      }

      return false;
    }

    #region Left button up

    private void OnMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
      OnMouseLeftButtonUp(e);
    }

    protected virtual void OnMouseLeftButtonUp(MouseButtonEventArgs e)
    {
      if (lmbPressed)
      {
        lmbPressed = false;
        RevertChanges();

        e.Handled = true;
      }
    }

    #endregion

    public void OnPlotterDetaching(Plotter plotter)
    {
      if (plotter.MainGrid != null)
      {
        hostPanel.MouseLeftButtonUp -= OnMouseLeftButtonUp;
        hostPanel.MouseLeftButtonDown -= OnMouseLeftButtonDown;
        hostPanel.MouseMove -= OnMouseMove;
        hostPanel.MouseWheel -= OnMouseWheel;

        hostPanel.MouseRightButtonDown -= OnMouseRightButtonDown;
        hostPanel.MouseRightButtonUp -= OnMouseRightButtonUp;
        
        hostPanel.LostFocus -= OnLostFocus;
      }
      listeningPanel = null;
      this.plotter = null;
    }

    private Plotter2D plotter;
    Plotter IPlotterElement.Plotter
    {
      get { return plotter; }
    }

    #endregion

    public override string ToString()
    {
      return "AxisNavigation: " + Placement;
    }
  }
}