Created undo/redo command for module remove, along with reapplying some module-specific attributes (state, charge). Fixed a bug when trying to add a module that doesn't fit

gui/fitCommands/moduleAdd.py

@@ -7,8 +7,8 @@ from gui import globalEvents as GE
 
 class FitModuleAddCommand(wx.Command):
     def __init__(self, fitID, itemID):
-        # todo: instead of modules, needs to be positions. Dead objects are a thing
         wx.Command.__init__(self, True, "Module Add")
+        # todo: evaluate mutaplasmid modules
         self.mainFrame = gui.mainFrame.MainFrame.getInstance()
         self.sFit = Fit.getInstance()
         self.fitID = fitID
@@ -16,6 +16,7 @@ class FitModuleAddCommand(wx.Command):
         self.new_position = None
 
     def Do(self):
+        # todo: figure how not to add this command to stack if module doesn't fit correctly.
         populate, self.new_position = self.sFit.appendModule(self.fitID, self.itemID)
         if populate is not None:
             # self.slotsChanged() # unsure how to handle this right now? Perhaps move this to the event itself?
@@ -23,7 +24,8 @@ class FitModuleAddCommand(wx.Command):
         return True
 
     def Undo(self):
-        # todo: self.slotsChanged()
-        result = self.sFit.removeModule(self.fitID, [self.new_position])
-        wx.PostEvent(self.mainFrame, GE.FitChanged(fitID=self.fitID, action="moddel", typeID=self.itemID))
+        if (self.new_position):
+            # todo: self.slotsChanged()
+            result = self.sFit.removeModule(self.fitID, [self.new_position])
+            wx.PostEvent(self.mainFrame, GE.FitChanged(fitID=self.fitID, action="moddel", typeID=self.itemID))
         return True