mvvm

+ (Class)viewModelClassForModel:(Class)modelClass {
  NSString *modelClassString = NSStringFromClass(modelClass);
  NSInteger suffixLength = [@"Model" length];
  NSString *viewModelClassString;
  NSRange range = NSMakeRange(modelClassString.length - suffixLength, suffixLength);
  viewModelClassString = [modelClassString stringByReplacingCharactersInRange:range
                                                                   withString:@"ViewModel"];
  Class viewModelClass = NSClassFromString(viewModelClassString);
  if (!viewModelClass) {
    NSLog(@"Internal Name convention broken.");
  }
  return viewModelClass;
}

+ (Class)viewClassForViewModel:(Class)viewModelClass {
  NSString *viewModelClassString = NSStringFromClass(viewModelClass);
  NSInteger suffixLength = [@"ViewModel" length];
  NSRange range = NSMakeRange(viewModelClassString.length - suffixLength, suffixLength);
  NSString *viewClassString;
  viewClassString = [viewModelClassString stringByReplacingCharactersInRange:range
                                                                  withString:@"View"];
  Class viewClass = NSClassFromString(viewClassString);
  if (!viewClass) {
    NSLog(@"Internal Name convention broken.");
  }
  return viewClass;
}