[longomatch] Implement clipping while moving timenode objects

[Andoni Morales Alastruey <amorales src gnome org>]

commit 5688537f64801e6ad86639643914f94ca6431d40
Author: Andoni Morales Alastruey <ylatuya gmail com>
Date:   Thu Apr 23 18:47:18 2015 +0200

    Implement clipping while moving timenode objects

 .../CanvasObjects/Timeline/TimeNodeObject.cs       |   12 +++++++++---
 1 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/LongoMatch.Drawing/CanvasObjects/Timeline/TimeNodeObject.cs 
b/LongoMatch.Drawing/CanvasObjects/Timeline/TimeNodeObject.cs
index 3ad6e12..d7ba80c 100644
--- a/LongoMatch.Drawing/CanvasObjects/Timeline/TimeNodeObject.cs
+++ b/LongoMatch.Drawing/CanvasObjects/Timeline/TimeNodeObject.cs
@@ -149,6 +149,8 @@ namespace LongoMatch.Drawing.CanvasObjects.Timeline
 
                public void Move (Selection sel, Point p, Point start)
                {
+                       double diffX;
+
                        // Apply dragging restrictions
                        if (DraggingMode == NodeDraggingMode.None)
                                return;
@@ -165,6 +167,7 @@ namespace LongoMatch.Drawing.CanvasObjects.Timeline
                        }
 
                        Time newTime = Utils.PosToTime (p, SecondsPerPixel);
+                       diffX = p.X - start.X;
 
                        if (p.X < 0) {
                                p.X = 0;
@@ -194,9 +197,12 @@ namespace LongoMatch.Drawing.CanvasObjects.Timeline
                                }
                                break;
                        case SelectionPosition.All:
-                               Time diff = Utils.PosToTime (new Point (p.X - start.X, p.Y), SecondsPerPixel);
-                               TimeNode.Start += diff;
-                               TimeNode.Stop += diff;
+                               Time diff = Utils.PosToTime (new Point (diffX, p.Y), SecondsPerPixel);
+                               if ((TimeNode.Start + diff) >= new Time (0) &&
+                                   (TimeNode.Start + diff) < MaxTime) {
+                                       TimeNode.Start += diff;
+                                       TimeNode.Stop += diff;
+                               }
                                break;
                        }
                        movingPos = sel.Position;