aman-satu-flutter/lib/widgets/tools/app_barcode_scanner_widget.dart

import 'package:ai_barcode/ai_barcode.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:permission_handler/permission_handler.dart';

late String _label;
late Function(String result) _resultCallback;

///
/// AppBarcodeScannerWidget
class AppBarcodeScannerWidget extends StatefulWidget {
  ///
  ///
  AppBarcodeScannerWidget.defaultStyle({
    Function(String result)? resultCallback,
    String label = 'Заголовок',
  }) {
    _resultCallback = resultCallback ?? (String result) {};
    _label = label;
  }

  @override
  _AppBarcodeState createState() => _AppBarcodeState();
}

class _AppBarcodeState extends State<AppBarcodeScannerWidget> {
  @override
  Widget build(BuildContext context) {
    return _BarcodePermissionWidget();
  }
}

class _BarcodePermissionWidget extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _BarcodePermissionWidgetState();
  }
}

class _BarcodePermissionWidgetState extends State<_BarcodePermissionWidget> {
  bool _isGranted = false;

  bool _useCameraScan = true;

  String _inputValue = "";

  @override
  void initState() {
    super.initState();
  }

  void _requestMobilePermission() async {
    if (await Permission.camera.request().isGranted) {
      setState(() {
        _isGranted = true;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    TargetPlatform platform = Theme.of(context).platform;
    if (!kIsWeb) {
      if (platform == TargetPlatform.android ||
          platform == TargetPlatform.iOS) {
        _requestMobilePermission();
      } else {
        setState(() {
          _isGranted = true;
        });
      }
    } else {
      setState(() {
        _isGranted = true;
      });
    }

    return Column(
      children: <Widget>[
        Expanded(
          child: _isGranted
              ? _BarcodeScannerWidget()
              : Center(
            child: OutlinedButton(
              onPressed: () {
                _requestMobilePermission();
              },
              child: const Text('Запроса на разрешения'),
            ),
          ),
        ),
        // _useCameraScan
        //     ? OutlinedButton(
        //   onPressed: () {
        //     setState(() {
        //       _useCameraScan = false;
        //     });
        //   },
        //   child: Text("Использовать камеру $_label"),
        // )
        //     : Row(
        //   children: [
        //     OutlineButton(
        //       onPressed: () {
        //         setState(() {
        //           _useCameraScan = true;
        //         });
        //       },
        //       child: Text("_useCameraScan = true $_label"),
        //     ),
        //     OutlineButton(
        //       onPressed: () {
        //         _resultCallback(_inputValue);
        //       },
        //       child: Text("_resultCallback"),
        //     ),
        //   ],
        // ),
      ],
    );
  }
}


///ScannerWidget
class _BarcodeScannerWidget extends StatefulWidget {
  @override
  State<StatefulWidget> createState() {
    return _AppBarcodeScannerWidgetState();
  }
}

class _AppBarcodeScannerWidgetState extends State<_BarcodeScannerWidget> {
  late ScannerController _scannerController;

  @override
  void initState() {
    super.initState();

    _scannerController = ScannerController(scannerResult: (result) {
      _resultCallback(result);
    }, scannerViewCreated: () {
      TargetPlatform platform = Theme.of(context).platform;
      if (TargetPlatform.iOS == platform) {
        Future.delayed(Duration(seconds: 2), () {
          _scannerController.startCamera();
          _scannerController.startCameraPreview();
        });
      } else {
        _scannerController.startCamera();
        _scannerController.startCameraPreview();
      }
    });
  }

  @override
  void dispose() {
    super.dispose();
    _scannerController.stopCameraPreview();
    _scannerController.stopCamera();
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: <Widget>[
        Expanded(
          child: _getScanWidgetByPlatform(),
        )
      ],
    );
  }

  Widget _getScanWidgetByPlatform() {
    return PlatformAiBarcodeScannerWidget(
      platformScannerController: _scannerController,
    );
  }
}