a system for storing program options

filmatyk/gui.py

@@ -9,6 +9,7 @@
 import filters
 from database import Database
 from filmweb import FilmwebAPI
+from options import Options
 from presenter import Presenter
 from updater import Updater
 from userdata import DataManager, UserData
@@ -81,6 +82,7 @@ def __construct(self):
     tk.Button(master=cw, text='Zaloguj', command=self._loginClick).grid(row=4, column=1, sticky=tk.W)
     tk.Button(master=cw, text='Anuluj', command=self._cancelClick).grid(row=4, column=0, sticky=tk.E)
     self.window.withdraw()
+
   def centerWindow(self):
     self.window.update()
     ws = self.window.winfo_screenwidth()
@@ -96,13 +98,15 @@ def _setStateBad(self, event=None, connection=False):
     message = self.conerr_message if connection else self.logerr_message
     self.infoLabel['text'] = message
     self.stateGood = False
+
   def _setStateGood(self, event=None):
     if not self.stateGood:
       self.infoLabel['text'] = ''
       self.stateGood = True
     #also, maybe the user has hit enter key, meaning to log in
     if event.keysym == 'Return':
       self._loginClick()
+
   def _loginClick(self):
     #collect login data
     username = self.usernameEntry.get()
@@ -120,13 +124,15 @@ def _loginClick(self):
       self.username = username
       self.isDone.set(True)
       self.window.withdraw()
+
   def _cancelClick(self):
     self.passwordEntry.delete(0, tk.END)
     self.usernameEntry.delete(0, tk.END)
     self.session = None
     self.isDone.set(True)
     self.window.withdraw()
 
+
 class Main(object):
   filename = 'filmatyk.dat'  # will be created in user documents/home directory
   wintitle = '{}Filmatyk'    # format with debug flag
@@ -136,6 +142,11 @@ def __init__(self, debugMode=False, isOnLinux=False):
     self.isOnLinux = isOnLinux
     self.root = root = tk.Tk()
     root.title(self.wintitle.format('[DEBUG] ' if self.debugMode else ''))
+    # load the savefile
+    self.dataManager = DataManager(self.getFilename(), VERSION)
+    userdata = self.dataManager.load()
+    # create the options manager
+    self.options = Options()
     # construct the window: first the notebook for tabbed view
     self.notebook = ttk.Notebook(root)
     self.notebook.grid(row=0, column=0, padx=5, pady=5, sticky=tk.NW)
@@ -158,9 +169,6 @@ def __init__(self, debugMode=False, isOnLinux=False):
     self.abortUpdate = False # database can set this via callback when something goes wrong
     self.databases = []
     self.presenters = []
-    # load the savefile
-    self.dataManager = DataManager(self.getFilename(), VERSION)
-    userdata = self.dataManager.load()
     # instantiate Presenters and Databases
     self.api = FilmwebAPI(self.loginHandler.requestLogin, userdata.username)
     movieDatabase = Database.restoreFromString('Movie', userdata.movies_data, self.api, self._setProgress)
@@ -221,6 +229,7 @@ def setStyle(self):
         'configure': {'width': 20, 'anchor': 'center'}
       }
     })
+
   def centerWindow(self):
     self.root.update()
     ws = self.root.winfo_screenwidth()
@@ -238,6 +247,7 @@ def getFilename(self):
     subpath = self.filename
     userdir = str(Path.home())
     return os.path.join(userdir, subpath)
+
   def saveUserData(self):
     # if for any reason the first update hasn't commenced - don't save anything
     if self.api.username is None:
@@ -278,6 +288,7 @@ def _setProgress(self, value:int, abort:bool=False):
       self.progressbar.grid()
       self.progressVar.set(value)
     self.root.update()
+
   def _updateData(self):
     # call softUpdate on all the databases and update all the presenters
     for db, ps in zip(self.databases, self.presenters):
@@ -288,13 +299,15 @@ def _updateData(self):
         break
     # save data
     self.saveUserData()
+
   def _reloadData(self):
     for db, ps in zip(self.databases, self.presenters):
       db.hardUpdate()
       ps.totalUpdate()
       if self.abortUpdate:
         break
     self.saveUserData()
+
   def _quit(self, restart=False):
     self.saveUserData()
     self.root.quit()
@@ -312,6 +325,7 @@ def _quit(self, restart=False):
         command += " debug"
       os.system(command)
 
+
 if __name__ == "__main__":
   debugMode = "debug" in sys.argv
   isOnLinux = "linux" in sys.argv

filmatyk/options.py

@@ -0,0 +1,47 @@
+import json
+import os
+
+import tkinter as tk
+from tkinter import ttk
+
+
+class Options():
+  """Stores program options as named Tk variables, allowing easy serialization.
+
+  Options wraps around a simple dict of Tk vars, which enables the following:
+  * easy access to option values (using get),
+  * simple binding of option variables to Tk widgets (using variable),
+  * serialization and deserialization to JSON (using storeToString).
+  Defining a new option is done simply by adding it to the prototypes list.
+  """
+  option_prototypes = [
+  ]
+
+  def __init__(self, json_string:str='{}'):
+    self.variables = {}
+    self.isDirty = False
+    saved_values = json.loads(json_string)
+    for name, vtype, default in self.option_prototypes:
+      variable = vtype()
+      value = saved_values[name] if name in saved_values.keys() else default
+      variable.set(value)
+      variable.trace('w', self.__touched_callback)
+      self.variables[name] = variable
+
+  def storeToString(self):
+    """Serialize the options to a JSON string."""
+    return json.dumps({
+      name: variable.get() for name, variable in self.variables.items()
+    })
+
+  def get(self, name):
+    """Get the value of a named option."""
+    return self.variables[name].get()
+
+  def variable(self, name):
+    """Get Tk variable object of a named option."""
+    return self.variables[name]
+
+  def __touched_callback(self, *args):
+    """Set the dirty flag whenever an option changes."""
+    self.isDirty = True