import 'package:flutter/material.dart';
import 'package:mobile_scanner/mobile_scanner.dart';

class BarcodeScannerScreen extends StatefulWidget {
  const BarcodeScannerScreen({super.key});

  @override
  State<BarcodeScannerScreen> createState() => _BarcodeScannerScreenState();
}

class _BarcodeScannerScreenState extends State<BarcodeScannerScreen> {
  bool _handled = false;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Escanear código')),
      body: Stack(
        children: [
          MobileScanner(
            onDetect: (capture) {
              if (_handled) return;
              final barcode = capture.barcodes.isNotEmpty
                  ? capture.barcodes.first.rawValue
                  : null;
              if (barcode == null || barcode.isEmpty) return;
              _handled = true;
              Navigator.of(context).pop(barcode);
            },
          ),
          // Visual guide overlay
          Center(
            child: Container(
              width: 240,
              height: 160,
              decoration: BoxDecoration(
                border: Border.all(color: Colors.white, width: 2),
                borderRadius: BorderRadius.circular(12),
              ),
            ),
          ),
          Positioned(
            bottom: 48,
            left: 0,
            right: 0,
            child: Center(
              child: Container(
                padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
                decoration: BoxDecoration(
                  color: Colors.black54,
                  borderRadius: BorderRadius.circular(20),
                ),
                child: const Text(
                  'Apunta el código de barras hacia el recuadro',
                  style: TextStyle(color: Colors.white, fontSize: 13),
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}