/// <summary>
/// When an entity is moved there are various possibilities:
/// <list type="bullet">
/// <item>
/// <term>a connector is moved</term>
/// <description>in this case the moved connector can only be part of a onnection because moving shape-connectors is not allowed unless by means of the <see cref="ConnectorMoverTool"/>.
/// If a connector attached to a connection is moved we have the following fork:
/// <list type="bullet">
/// <item>the connector was attached</item>
/// <description>the connector has a parent and needs to be detached before being moved and eventually attached to another connector</description>
/// <item>the connector is moved</item>
/// <description>this is a standard motion and is similar for any <see cref="IDiagramEntity"/>
/// </description>
/// <item>the connector ends up somewhere near another connector and will become attached to it</item>
/// <description>the connector in the proximity of the moved connector will become the parent of it. Note that we previously detached any binding and that a connector can have only one parent.</description>
/// </list>
/// </description>
/// </item>
/// <item>an entity is moved</item>
/// <description>the normal <see cref="MoveCommand"/> can be used</description>
/// <item>a set of entities is moved</item>
/// <description>we need to create a bundle to package the entities and then use the <see cref="MoveCommand"/></description>
/// </list>
/// Several important remarks are in order here:
/// <list type="bullet">
/// <item>a connector can have only one parent</item>
/// <item>we need to package a move action in a command but this command needs NOT to be performed (i.e. call the Redo() method) because the motion already occured through the MouseMove handler. Because of this situation we cannot perform a Redo() on the full package since it would move the entities twice. Hence, commands are execute just after their creation (except for the move).
/// <item>when the stack of actions are undone the stack has to be reverted</item>
/// </item>
/// <item>whatever the situation is, the most economical way to code the different cases is by means of a <see cref="CompoundCommand"/> object</item>
/// </list>
/// </summary>
/// <param name="e">The <see cref="T:System.Windows.Forms.MouseEventArgs"/> instance containing the event data.</param>
public void MouseUp(MouseEventArgs e)
{
if(IsActive)
{
DeactivateTool();
//creation of the total undoredo package
CompoundCommand package = new CompoundCommand(this.Controller);
string message = string.Empty;
//notice that the connector can only be a connection connector because of the MouseDown check above
if(connectorMove)
{
#region We are moving a connection-connector
#region Is the connector attached?
//detach only if there is a parent different than a connection; the join of a chained connection is allowed to move
if( Selection.Connector.AttachedTo != null && !typeof(IConnection).IsInstanceOfType(Selection.Connector.AttachedTo))
{
DetachConnectorCommand detach = new DetachConnectorCommand(this.Controller, Selection.Connector.AttachedTo, Selection.Connector);
detach.Redo();
package.Commands.Add(detach);
}
#endregion
#region The moving part
//a bundle might look like overkill here but it makes the coding model uniform
Bundle bundle = new Bundle(Controller.Model);
bundle.Entities.Add(Selection.Connector);
MoveCommand move = new MoveCommand(this.Controller, bundle, new Point(lastPoint.X - initialPoint.X, lastPoint.Y - initialPoint.Y));
//no Redo() necessary here!
package.Commands.Add(move);
#endregion
#region The re-attachment near another connector
//let's see if the connection endpoints hit other connectors (different than the selected one!)
//define a predicate delegate to filter things out otherwise the hit will return the moved connector which would results
//in a stack overflow later on
Predicate<IConnector> predicate =
delegate(IConnector conn)
{
//whatever, except itself and any children of the moved connector
//since this would entail a child becoming a parent!
if(conn.Hit(e.Location) && conn != Selection.Connector && !Selection.Connector.AttachedConnectors.Contains(conn))
return true;
return false;
};
//find it!
IConnector parentConnector = Selection.FindConnector(predicate);
if(parentConnector != null) //aha, there's an attachment
{
BindConnectorsCommand binder = new BindConnectorsCommand(this.Controller, parentConnector, Selection.Connector);
package.Commands.Add(binder);
binder.Redo(); //this one is necessary since the redo cannot be performed on the whole compound command
}
#endregion
message = "Connector move";
#endregion
}
else
{
#region We are moving entities other than a connector
Bundle bundle = new Bundle(Controller.Model);
bundle.Entities.AddRange(Selection.SelectedItems);
MoveCommand cmd = new MoveCommand(this.Controller, bundle, new Point(lastPoint.X - initialPoint.X, lastPoint.Y - initialPoint.Y));
package.Commands.Add(cmd);
//not necessary to perform the Redo action of the command since the mouse-move already moved the bundle!
#endregion
message = "Entities move";
}
//reset the hovered connector, if any
if (hoveredConnector != null)
hoveredConnector.Hovered = false;
package.Text = message;
//whatever the content of the package we add it to the undo history
this.Controller.UndoManager.AddUndoCommand(package);
//show the tracker again
this.Controller.View.ShowTracker();
}
}
/// <summary>
/// Handles the mouse up event
/// </summary>
/// <param name="e">The <see cref="T:System.Windows.Forms.MouseEventArgs"/> instance containing the event data.</param>
public void MouseUp(MouseEventArgs e) {
if (IsActive) {
DeactivateTool();
if (fetchedConnector == null)
return;
Bundle bundle = new Bundle(Controller.Model);
bundle.Entities.Add(fetchedConnector);
MoveCommand cmd = new MoveCommand(this.Controller, bundle, new Point(lastPoint.X - initialPoint.X, lastPoint.Y - initialPoint.Y));
Controller.UndoManager.AddUndoCommand(cmd);
//not necessary to perform the Redo action of the command since the mouse-move already moved the bundle!
}
}
