ChickenFarm/UI/CF.APP/chicken_farm/lib/components/qr_scanner.dart

import 'package:chicken_farm/core/utils/logger.dart';
import 'package:flutter/material.dart';
import 'package:mobile_scanner/mobile_scanner.dart';
import 'package:chicken_farm/core/utils/toast.dart';
import 'package:audioplayers/audioplayers.dart';

typedef OnScanCallback = void Function(String scannedContent);
typedef QRCodeParser = Future<String?> Function(String rawContent);

class QRScannerComponent extends StatefulWidget {
  final String? startWithString;
  final OnScanCallback onScanCallback;
  final String? invalidQRMessage;
  final QRCodeParser? qrCodeParser;

  const QRScannerComponent({
    super.key,
    this.startWithString,
    required this.onScanCallback,
    this.invalidQRMessage,
    this.qrCodeParser,
  });

  @override
  State<QRScannerComponent> createState() => _QRScannerComponentState();
}

class _QRScannerComponentState extends State<QRScannerComponent> {
  MobileScannerController? _cameraController;
  bool _isScanning = false;
  bool _isTorchOn = false;
  final AudioPlayer _audioPlayer = AudioPlayer();

  @override
  void initState() {
    super.initState();
    _cameraController = MobileScannerController();
  }

  @override
  void dispose() {
    _cameraController?.dispose();
    _audioPlayer.dispose();
    super.dispose();
  }

  void _handleBarcodeScan(BarcodeCapture barcode) async {
    // 如果正在扫描或冷却中，则忽略
    logger.d('扫描二维码: $barcode');
    if (_isScanning) return;
    ToastUtil.info("正在扫描二维码...");
    _isScanning = true;
    final code = barcode.barcodes.first.rawValue;

    // 播放提示音
    await _audioPlayer.play(AssetSource('sounds/beep.mp3'));

    if (code == null) {
      _resetScanningState('无法识别二维码');
      return;
    }

    _processQRCode(code);
  }

  void _processQRCode(String code) async {
    // 如果设置了起始字符串，则检查是否匹配
    if (widget.startWithString != null &&
        !code.startsWith(widget.startWithString!)) {
      final errorMessage = widget.invalidQRMessage ?? '非法二维码';
      _resetScanningState(errorMessage);
      return;
    }
    if (widget.qrCodeParser != null) {
      try {
        final parseCode = await widget.qrCodeParser!(code);
        if (parseCode == null || parseCode.isEmpty) {
          // 解析失败，显示错误并重置状态
          _resetScanningState('二维码解析失败');
          return;
        }
        code = parseCode;
      } catch (e) {
        // 解析过程中出现异常
        _resetScanningState('二维码解析异常: $e');
        return;
      }
    }
    widget.onScanCallback(code);
    _resetScanningState();
  }

  void _resetScanningState([String? errorMessage]) {
    if (errorMessage != null) {
      ToastUtil.errorAlert(errorMessage);
    }
    Future.delayed(const Duration(seconds: 1), () {
      if (mounted) {
        _isScanning = false;
      }
    });
  }

  void _toggleTorch() async {
    if (_cameraController != null) {
      await _cameraController!.toggleTorch();
      setState(() {
        _isTorchOn = !_isTorchOn;
      });
    }
  }

  @override
  Widget build(BuildContext context) {
    const scanBoxSize = 250.0;

    return Scaffold(
      body: SafeArea(
        child: LayoutBuilder(
          builder: (context, constraints) {
            var cw = constraints.maxWidth;
            var ch = constraints.maxHeight;
            var w = cw / 2 - scanBoxSize / 2;
            var h = ch / 2 - scanBoxSize / 2;
            var scanRefc = Rect.fromLTWH(w, h, scanBoxSize, scanBoxSize);

            return Stack(
              children: [
                MobileScanner(
                  controller: _cameraController,
                  onDetect: _handleBarcodeScan,
                  scanWindow: scanRefc,
                ),
                Align(
                  alignment: Alignment.center,
                  child: Container(
                    width: scanBoxSize,
                    height: scanBoxSize,
                    decoration: BoxDecoration(
                      border: Border(
                        left: BorderSide(color: Colors.white, width: 2),
                        right: BorderSide(color: Colors.white, width: 2),
                        top: BorderSide(color: Colors.white, width: 2),
                        bottom: BorderSide(color: Colors.white, width: 2),
                      ),
                    ),
                  ),
                ),
                // 顶部黑色遮罩
                Positioned(
                  top: 0,
                  left: 0,
                  right: 0,
                  bottom: h + scanBoxSize,
                  child: Container(color: Colors.black.withValues(alpha: 0.7)),
                ),
                // 底部黑色遮罩
                Positioned(
                  top: h + scanBoxSize,
                  left: 0,
                  right: 0,
                  bottom: 0,
                  child: Container(color: Colors.black.withValues(alpha: 0.7)),
                ),
                // 左侧黑色遮罩
                Positioned(
                  top: h,
                  left: 0,
                  width: w,
                  height: scanBoxSize,
                  child: Container(color: Colors.black.withValues(alpha: 0.7)),
                ),
                // 右侧黑色遮罩
                Positioned(
                  top: h,
                  right: 0,
                  width: w,
                  height: scanBoxSize,
                  child: Container(color: Colors.black.withValues(alpha: 0.7)),
                ),
                //底部手电筒按钮
                Positioned(
                  top: h + scanBoxSize + 40,
                  left: 0,
                  right: 0,
                  child: Center(
                    child: IconButton(
                      icon: Icon(
                        _isTorchOn ? Icons.flashlight_on : Icons.flashlight_off,
                        color: Colors.white,
                        size: 36,
                      ),
                      onPressed: _toggleTorch,
                    ),
                  ),
                ),
              ],
            );
          },
        ),
      ),
    );
  }
}