refactor(package): split the code into more files

example/lib/example_buttons.dart

@@ -1,6 +1,6 @@
 import 'package:flutter/cupertino.dart';
 import 'package:flutter/material.dart';
-import 'package:flutter_card_swiper/card_swiper.dart';
+import 'package:flutter_card_swiper/flutter_card_swiper.dart';
 
 class ExampleButton extends StatelessWidget {
   final Function onTap;

example/lib/main.dart

@@ -3,7 +3,7 @@ import 'dart:developer';
 import 'package:example/example_candidate_model.dart';
 import 'package:example/example_card.dart';
 import 'package:flutter/cupertino.dart';
-import 'package:flutter_card_swiper/card_swiper.dart';
+import 'package:flutter_card_swiper/flutter_card_swiper.dart';
 
 import 'example_buttons.dart';
 

lib/flutter_card_swiper.dart

@@ -0,0 +1,3 @@
+export 'package:flutter_card_swiper/src/card_swiper.dart';
+export 'package:flutter_card_swiper/src/card_swiper_controller.dart';
+export 'package:flutter_card_swiper/src/enums.dart';

lib/src/card_swiper.dart

@@ -1,6 +1,8 @@
 import 'dart:math';
 
 import 'package:flutter/material.dart';
+import 'package:flutter_card_swiper/src/card_swiper_controller.dart';
+import 'package:flutter_card_swiper/src/enums.dart';
 
 class CardSwiper extends StatefulWidget {
   /// list of widgets for the swiper
@@ -402,32 +404,3 @@ class _CardSwiperState extends State<CardSwiper>
 //for null safety
 void emptyFunction() {}
 void emptyFunctionIndex(int index, CardSwiperDirection direction) {}
-
-//to call the swipe function from outside of the CardSwiper
-class CardSwiperController extends ChangeNotifier {
-  CardSwiperState? state;
-
-  //swipe the card by changing the status of the controller
-  void swipe() {
-    state = CardSwiperState.swipe;
-    notifyListeners();
-  }
-
-  //swipe the card to the left side by changing the status of the controller
-  void swipeLeft() {
-    state = CardSwiperState.swipeLeft;
-    notifyListeners();
-  }
-
-  //swipe the card to the right side by changing the status of the controller
-  void swipeRight() {
-    state = CardSwiperState.swipeRight;
-    notifyListeners();
-  }
-}
-
-enum CardSwiperState { swipe, swipeLeft, swipeRight }
-
-enum CardSwiperDirection { none, left, right, top, bottom }
-
-enum SwipeType { none, swipe, back }

lib/src/card_swiper_controller.dart

@@ -0,0 +1,25 @@
+//to call the swipe function from outside of the CardSwiper
+import 'package:flutter/widgets.dart';
+import 'package:flutter_card_swiper/src/enums.dart';
+
+class CardSwiperController extends ChangeNotifier {
+  CardSwiperState? state;
+
+  //swipe the card by changing the status of the controller
+  void swipe() {
+    state = CardSwiperState.swipe;
+    notifyListeners();
+  }
+
+  //swipe the card to the left side by changing the status of the controller
+  void swipeLeft() {
+    state = CardSwiperState.swipeLeft;
+    notifyListeners();
+  }
+
+  //swipe the card to the right side by changing the status of the controller
+  void swipeRight() {
+    state = CardSwiperState.swipeRight;
+    notifyListeners();
+  }
+}

lib/src/enums.dart

@@ -0,0 +1,5 @@
+enum CardSwiperState { swipe, swipeLeft, swipeRight }
+
+enum CardSwiperDirection { none, left, right, top, bottom }
+
+enum SwipeType { none, swipe, back }