implemented making a pdf from DetailPage.dart and croping image to 1:1 format

lib/AddPage.dart

@@ -1,8 +1,10 @@
 import 'dart:io';
+import 'dart:math';
 import 'package:firebase_storage/firebase_storage.dart';
 import 'package:flutter/material.dart';
 import 'package:image_picker/image_picker.dart';
 import 'package:cloud_firestore/cloud_firestore.dart';
+import 'package:image/image.dart' as img;
 
 
 class AddScreen extends StatefulWidget {
@@ -35,6 +37,27 @@ class _AddScreenState extends State<AddScreen> {
     return fileSize <= maxSizeInBytes;
   }
 
+  Future<File> _cropImage(File imageFile) async {
+    final originalImage = img.decodeImage(await imageFile.readAsBytes());
+
+    if (originalImage != null) {
+      int originSize = min(originalImage.width, originalImage.height);
+      final croppedImage = img.copyCrop(
+          originalImage,
+          x: (originalImage.width - originSize)~/2,
+          y: (originalImage.height - originSize)~/2,
+          width: originSize,
+          height: originSize
+      );
+      final newPath = imageFile.path.substring(0, imageFile.path.lastIndexOf('/'));
+      final newFile = File('$newPath/cropped.jpg');
+      await newFile.writeAsBytes(img.encodePng(croppedImage));
+      return newFile;
+    } else {
+      throw Exception('Unable to decode image file.');
+    }
+  }
+
   Future<void> _getImage(ImageSource source) async {
     final pickedFile = await ImagePicker().pickImage(source: source);
 
@@ -42,8 +65,9 @@ class _AddScreenState extends State<AddScreen> {
       final tempFile = File(pickedFile.path);
       final bool isValid = await isFileSizeValid(tempFile, 10);
       if (isValid) {
+        File croppedFile = await _cropImage(tempFile);  // Bild zuschneiden
         setState(() {
-          _imageFile = tempFile;
+          _imageFile = croppedFile;
         });
       } else {
         ScaffoldMessenger.of(context).showSnackBar(
@@ -53,6 +77,7 @@ class _AddScreenState extends State<AddScreen> {
     }
   }
 
+
   Future<void> addNewElementToFirestore(String title, String description, File imageFile, {required Function(bool) onComplete}) async {
     String collectionName;
     if (_selectedIndex == 0) {