Settings.py

"""
OpenTTTools Settings
Slight override of a typical dict to make the file auto save when a change is made
"""

import collections, json, os


class Settings(collections.MutableMapping):

    def __init__(self, filename):
        self.filename = filename

        self.data = {}

        # Make sure the file exists
        if os.path.exists(self.filename):
            try:
                with open(self.filename, 'r') as f:
                    self.data = json.load(f)
            except:
                # Something went wrong with the file, probable corruption, make a new one
                self.save()
        # If not, create it
        else:
            self.save()

    def save(self):
        """ Write settings changes to the json file """
        with open(self.filename, 'w') as jsonFile:
            json.dump(self.data, jsonFile, indent = 4)
            print('Saved settings')

    ''' Overrides '''

    def __getitem__(self, key):
        """ x = settings['setting'] override """
        return self.data[key]

    def __setitem__(self, key, value):
        """ settings['setting'] = 'value' override """
        self.data[key] = value
        # Save the file
        self.save()

    def __delitem__(self, key):
        """ del settings['setting'] override """
        del self.data[key]
        # Save the file
        self.save()

    def __iter__(self):
        """ iteration override (e.g. for x in settings) """
        return iter(self.data)

    def __len__(self):
        """ len(settings) Override """
        return len(self.data)