week 5 refactor

5 files changed, 43 insertions, 19 deletions

diff --git a/src/main/python/main.py b/src/main/python/main.py
index dfbb8c8..a2aaf8b 100644
--- a/src/main/python/main.py
+++ b/src/main/python/main.py
@@ -62,7 +62,7 @@ class appWindow(QMainWindow):
         self.mdi.subWindowActivated.connect(self.tabSwitched)
     
     def updateMenuBar(self):
-        # self.undo.setAction(self.activeScene.painter.undoAction)
+        # used to update menu bar undo-redo buttons to current scene
         self.undo.triggered.connect(self.activeScene.painter.undoAction.trigger())
         self.redo.triggered.connect(self.activeScene.painter.redoAction.trigger())
                 
diff --git a/src/main/python/utils/app.py b/src/main/python/utils/app.py
index 6339ca3..4540a43 100644
--- a/src/main/python/utils/app.py
+++ b/src/main/python/utils/app.py
@@ -1,5 +1,10 @@
+"""
+Declare fbs application so that it can be imported in other modules.
+"""
+
 from fbs_runtime.application_context.PyQt5 import ApplicationContext
 app = ApplicationContext()
 
 def fileImporter(file):
+    # Helper function to fetch files from src/main/resources
     return app.get_resource(file)
diff --git a/src/main/python/utils/data.py b/src/main/python/utils/data.py
index a96554e..3b32008 100644
--- a/src/main/python/utils/data.py
+++ b/src/main/python/utils/data.py
@@ -1,3 +1,7 @@
+"""
+Imports data from json configs, so that they can be imported from this module.
+"""
+
 from json import load
 from .app import fileImporter
 
diff --git a/src/main/python/utils/graphics.py b/src/main/python/utils/graphics.py
index 6b074ce..fdc0a40 100644
--- a/src/main/python/utils/graphics.py
+++ b/src/main/python/utils/graphics.py
@@ -20,6 +20,7 @@ class customView(QGraphicsView):
         self.setDragMode(True) #sets pannable using mouse
         self.setAcceptDrops(True) #sets ability to accept drops
         if scene:
+            #create necessary undo redo actions to accept keyboard shortcuts
             self.addAction(scene.undoAction)
             self.addAction(scene.redoAction)
             self.addAction(scene.deleteAction)
@@ -78,17 +79,16 @@ class customView(QGraphicsView):
         
 class customScene(QGraphicsScene):
     """
-    re-implement QGraphicsScene for future functionality 
-    hint: QUndoFramework
+    Extends QGraphicsScene with undo-redo functionality
     """
     def __init__(self, *args, parent=None):
         super(customScene, self).__init__(*args,  parent=parent)
         
-        self.undoStack = QUndoStack(self)
-        self.createActions()
-        
+        self.undoStack = QUndoStack(self) #Used to store undo-redo moves
+        self.createActions() #creates necessary actions that need to be called for undo-redo
 
     def createActions(self):
+        # helper function to create delete, undo and redo shortcuts
         self.deleteAction = QAction("Delete Item", self)
         self.deleteAction.setShortcut(Qt.Key_Delete)
         self.deleteAction.triggered.connect(self.deleteItem)
@@ -99,35 +99,40 @@ class customScene(QGraphicsScene):
         self.redoAction.setShortcut(QKeySequence.Redo)
     
     def createUndoView(self, parent):
+        # creates an undo stack view for current QGraphicsScene
         undoView = QUndoView(self.undoStack, parent)
         showUndoDialog(undoView, parent)
 
     def deleteItem(self):
+        # (slot) used to delete all selected items, and add undo action for each of them
         if self.selectedItems():
             for item in self.selectedItems():
                 self.undoStack.push(deleteCommand(item, self))
             
     def itemMoved(self, movedItem, lastPos):
+        #item move event, checks if item is moved
         self.undoStack.push(moveCommand(movedItem, lastPos))
     
     def addItemPlus(self, item):
-        # returnVal =  self.addItem(item)
+        # extended add item method, so that a corresponding undo action is also pushed
         self.undoStack.push(addCommand(item, self))
-        # return returnVal
-    
+        
     def mousePressEvent(self, event):
-        bdsp = event.buttonDownScenePos(Qt.LeftButton)
-        point = QPointF(bdsp.x(), bdsp.y())
-        itemList = self.items(point)
-        self.movingItem = itemList[0] if itemList else None
+        # overloaded mouse press event to check if an item was moved
+        bdsp = event.buttonDownScenePos(Qt.LeftButton) #get click pos
+        point = QPointF(bdsp.x(), bdsp.y()) #create a Qpoint from click pos
+        itemList = self.items(point) #get items at said point
+        self.movingItem = itemList[0] if itemList else None #set first item in list as moving item
         if self.movingItem and event.button() == Qt.LeftButton:
-            self.oldPos = self.movingItem.pos()
-        self.clearSelection()
+            self.oldPos = self.movingItem.pos() #if left click is held, then store old pos
+        self.clearSelection() #clears selected items
         return super(customScene, self).mousePressEvent(event)
     
     def mouseReleaseEvent(self, event):
+        # overloaded mouse release event to check if an item was moved
         if self.movingItem and event.button() == Qt.LeftButton:
             if self.oldPos != self.movingItem.pos():
+                #if item pos had changed, when mouse was realeased, emit itemMoved signal
                 self.itemMoved(self.movingItem, self.oldPos)
-            self.movingItem = None
+            self.movingItem = None #clear movingitem reference
         return super(customScene, self).mouseReleaseEvent(event)
diff --git a/src/main/python/utils/undo.py b/src/main/python/utils/undo.py
index 7832483..4dbcc46 100644
--- a/src/main/python/utils/undo.py
+++ b/src/main/python/utils/undo.py
@@ -1,7 +1,12 @@
+"""
+Contains custom undo commands that can be pushed to undo stack
+"""
 from PyQt5.QtWidgets import QUndoCommand
 
 class addCommand(QUndoCommand):
-    
+    """
+    QUndoCommand for add item event
+    """
     def __init__(self, addItem, scene, parent = None):
         super(addCommand, self).__init__(parent)
         self.scene = scene
@@ -20,7 +25,9 @@ class addCommand(QUndoCommand):
         self.scene.update()
         
 class deleteCommand(QUndoCommand):
-    
+    """
+    QUndoCommand for delete item event
+    """
     def __init__(self, item, scene, parent = None):
         super(deleteCommand, self).__init__(parent)
         self.scene = scene
@@ -36,7 +43,9 @@ class deleteCommand(QUndoCommand):
         self.scene.removeItem(self.diagramItem)
         
 class moveCommand(QUndoCommand):
-    
+    """
+    QUndoCommand for move item event
+    """
     def __init__(self, item, lastPos, parent = None):
         super(moveCommand, self).__init__(parent)
         self.diagramItem = item
@@ -53,6 +62,7 @@ class moveCommand(QUndoCommand):
         self.setText(f"Move {self.diagramItem} {self.newPos}")
         
     def mergeWith(self, move):
+        #merges multiple move commands so that a move event is not added twice.
         item = move.diagramItem
         
         if self.diagramItem != item: