Tutorius: Adding State and FSM stubs

1 files changed, 64 insertions, 0 deletions

diff --git a/src/sugar/tutorius/tutorial.py b/src/sugar/tutorius/tutorial.py
index 5236127..fc1d8ae 100644
--- a/src/sugar/tutorius/tutorial.py
+++ b/src/sugar/tutorius/tutorial.py
@@ -160,3 +160,67 @@ class Tutorial (object):
                     continue
         
 
+class State:
+    """This is a step in a tutorial. The state represents a collection of 
+    actions to undertake when entering the state, and a description of an
+    event filter with associated actions to go to the next state."""
+    
+    def __init__(self):
+        """Initializes the content of the state, as in loading the actions
+        that are required and building the correct tests."""
+        self.actions = []
+        self.tests = []
+        
+    
+    def setup(self):
+        """Install the state itself. This is the best time to pop-up a dialog
+        that has to remain for the duration of the state."""
+        for act in self.actions:
+            act.do()
+            
+    
+    def teardown(self):
+        """Undo every action that was installed for this state. This means 
+        removing dialogs that were displayed, removing highlights, etc..."""
+        for act in self.actions:
+            act.undo()
+        
+    
+    def verify(self):
+        """Run the internal tests to see if one of them passes. If it does, 
+        then do the associated processing to go in the next state.""" 
+        for test in self.tests:
+            if test.verify() == True:
+                actions = test.get_actions()
+                for act in actions:
+                    act.do()
+                # Now that we execute the actions related to a test, we might
+                # want to undo them right after --- should we use a callback or
+                # a timer?
+    
+class FiniteStateMachine(State):
+    """This is a collection of states, with a start state and an end callback.
+    It is used to simplify the development of the various tutorials by 
+    encapsulating a collection of states that represent a given learning 
+    process."""
+    def __init__(self, start_state, setup_actions):
+        """The constructor for a FSM. Pass in the start state and the setup
+        actions that need to be taken when the FSM itself start (which may be
+        different from what is done in the first state of the machine)."""
+        self.start_state = start_state
+        self.actions = setup_actions
+        
+        self.tests = []
+        
+        self.current_state = self.start_state
+    
+    def setup(self):
+        for act in self.actions:
+            act.do()
+    
+    def teardown(self):
+        for act in self.actions:
+            act.undo
+    
+    def verify(self):
+        return self.current_state.verify()
\ No newline at end of file