import 'dart:io';
import 'dart:typed_data';
import 'package:flutter/material.dart';
import 'package:image_picker/image_picker.dart';
import 'package:google_mlkit_barcode_scanning/google_mlkit_barcode_scanning.dart';
import 'package:provider/provider.dart';

import '../../providers/user_provider.dart';

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

  @override
  State<BindAccountPage> createState() => _BindAccountPageState();
}

class _BindAccountPageState extends State<BindAccountPage> {
  final TextEditingController _qrContentController = TextEditingController();
  final ImagePicker _picker = ImagePicker();

  bool _isProcessing = false;
  String? _statusMessage;
  File? _selectedImageFile; // 用户选择的原始二维码截图

  // 条码扫描器
  final BarcodeScanner _barcodeScanner = BarcodeScanner(
    formats: [BarcodeFormat.qrCode],
  );

  @override
  void dispose() {
    _qrContentController.dispose();
    _barcodeScanner.close();
    super.dispose();
  }

  // 1. 选择图片并识别二维码
  Future<void> _pickImageAndScan() async {
    try {
      final XFile? pickedFile = await _picker.pickImage(source: ImageSource.gallery);
      if (pickedFile == null) return;

      setState(() {
        _isProcessing = true;
        _statusMessage = "正在识别二维码...";
        _selectedImageFile = File(pickedFile.path);
      });

      final inputImage = InputImage.fromFilePath(pickedFile.path);
      final List<Barcode> barcodes = await _barcodeScanner.processImage(inputImage);

      setState(() {
        _isProcessing = false;
      });

      if (barcodes.isNotEmpty && barcodes.first.rawValue != null) {
        final String code = barcodes.first.rawValue!;
        setState(() {
          _qrContentController.text = code;
          _statusMessage = "识别成功";
        });
      } else {
        setState(() {
          _statusMessage = "未识别到二维码，请手动输入";
        });
      }

    } catch (e) {
      setState(() {
        _isProcessing = false;
        _statusMessage = "识别失败: $e";
      });
    }
  }

  // 2. 执行隐写并上传 (触发后端绑定/登录逻辑)
  Future<void> _handleBind() async {
    final qrContent = _qrContentController.text.trim();

    if (qrContent.isEmpty) {
      ScaffoldMessenger.of(context).showSnackBar(
        const SnackBar(content: Text("请输入或扫描二维码内容"), backgroundColor: Colors.orange),
      );
      return;
    }

    Uint8List? imageBytes;

    setState(() {
      _isProcessing = true;
      _statusMessage = "正在处理图片...";
    });

    try {
      final httpClient = HttpClient();
      final request = await httpClient.getUrl(Uri.parse('https://union.godserver.cn/assets/jpeg/20180621142015_5FmGZ-wYXkyL4y.jpeg'));
      final response = await request.close();
      final bytes = <int>[];
      await for (final chunk in response) {
        bytes.addAll(chunk);
      }
      imageBytes = Uint8List.fromList(bytes);

      if (imageBytes == null || imageBytes.isEmpty) throw Exception("图片数据无效");

      setState(() {
        _statusMessage = "正在提交绑定请求...";
      });

      // 调用 Provider
      // 注意：这里 segaId 参数其实传的是 QR Code 的内容
      final userProvider = context.read<UserProvider>();
      final result = await userProvider.uploadStegImage(imageBytes, segaId: qrContent);

      setState(() {
        _isProcessing = false;
      });

      // 处理后端返回
      if (mounted) {
        if (result['code'] == 200) {
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text("✅ ${result['msg']}"), backgroundColor: Colors.green, duration: const Duration(seconds: 5)),
          );
          // 绑定成功后，通常建议刷新用户信息
          await userProvider.initUser();
        } else {
          // 后端返回 500 或其他错误
          ScaffoldMessenger.of(context).showSnackBar(
            SnackBar(content: Text("❌ ${result['msg']}"), backgroundColor: Colors.red, duration: const Duration(seconds: 5)),
          );
        }
      }

    } catch (e) {
      setState(() {
        _isProcessing = false;
        _statusMessage = "网络或处理错误: $e";
      });
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text("错误: $e"), backgroundColor: Colors.red),
        );
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("绑定 / 刷新 Sega 账号"),
        backgroundColor: Colors.black.withOpacity(0.5),
        elevation: 0,
      ),
      body: Stack(
        fit: StackFit.expand,
        children: [
          // 背景图
          Image.network(
            'https://union.godserver.cn/assets/jpeg/20180621142015_5FmGZ-wYXkyL4y.jpeg',
            fit: BoxFit.cover,
            loadingBuilder: (context, child, loadingProgress) {
              if (loadingProgress == null) return child;
              return Container(color: Colors.black);
            },
            errorBuilder: (context, error, stackTrace) => Container(color: Colors.grey[900]),
          ),

          // 遮罩
          Container(color: Colors.black.withOpacity(0.75)),

          // 内容
          SafeArea(
            child: Center(
              child: SingleChildScrollView(
                padding: const EdgeInsets.all(24.0),
                child: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    const Icon(Icons.qr_code_scanner, size: 60, color: Colors.white70),
                    const SizedBox(height: 16),
                    const Text(
                      "请提供 Sega 登录二维码",
                      style: TextStyle(fontSize: 18, color: Colors.white, fontWeight: FontWeight.bold),
                    ),
                    const SizedBox(height: 8),
                    const Text(
                      "支持识别截图或手动输入二维码内容\n用于绑定账号或刷新登录状态",
                      style: TextStyle(fontSize: 14, color: Colors.white60),
                      textAlign: TextAlign.center,
                    ),
                    const SizedBox(height: 30),

                    // 输入卡片
                    Container(
                      padding: const EdgeInsets.all(20),
                      decoration: BoxDecoration(
                        color: Colors.white.withOpacity(0.1),
                        borderRadius: BorderRadius.circular(16),
                        border: Border.all(color: Colors.white.withOpacity(0.2)),
                      ),
                      child: Column(
                        children: [
                          TextField(
                            controller: _qrContentController,
                            style: const TextStyle(color: Colors.white),
                            maxLines: 10,
                            decoration: InputDecoration(
                              labelText: "二维码内容 (QR Data)",
                              labelStyle: const TextStyle(color: Colors.white70),
                              hintText: "例如: SGWCMAID...",
                              hintStyle: const TextStyle(color: Colors.white38),
                              enabledBorder: OutlineInputBorder(
                                borderSide: const BorderSide(color: Colors.white38),
                                borderRadius: BorderRadius.circular(12),
                              ),
                              focusedBorder: OutlineInputBorder(
                                borderSide: const BorderSide(color: Colors.white),
                                borderRadius: BorderRadius.circular(12),
                              ),
                            ),
                          ),

                          const SizedBox(height: 20),

                          // 预览图
                          if (_selectedImageFile != null)
                            ClipRRect(
                              borderRadius: BorderRadius.circular(8),
                              child: Image.file(_selectedImageFile!, height: 120, fit: BoxFit.contain),
                            ),

                          if (_selectedImageFile != null) const SizedBox(height: 15),

                          // 按钮组
                          Row(
                            children: [
                              Expanded(
                                child: ElevatedButton.icon(
                                  onPressed: _isProcessing ? null : _pickImageAndScan,
                                  icon: const Icon(Icons.image_search),
                                  label: const Text("识别截图"),
                                  style: ElevatedButton.styleFrom(
                                    backgroundColor: Colors.blueAccent,
                                    foregroundColor: Colors.white,
                                    padding: const EdgeInsets.symmetric(vertical: 12),
                                  ),
                                ),
                              ),
                              const SizedBox(width: 12),
                              Expanded(
                                child: ElevatedButton.icon(
                                  onPressed: _isProcessing ? null : _handleBind,
                                  icon: _isProcessing
                                      ? const SizedBox(width: 16, height: 16, child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white))
                                      : const Icon(Icons.login),
                                  label: Text(_isProcessing ? "处理中" : "绑定/刷新"),
                                  style: ElevatedButton.styleFrom(
                                    backgroundColor: Colors.green,
                                    foregroundColor: Colors.white,
                                    padding: const EdgeInsets.symmetric(vertical: 12),
                                  ),
                                ),
                              ),
                            ],
                          ),
                        ],
                      ),
                    ),

                    // 状态消息
                    if (_statusMessage != null)
                      Padding(
                        padding: const EdgeInsets.only(top: 20),
                        child: Text(
                          _statusMessage!,
                          style: TextStyle(
                            color: _statusMessage!.contains("失败") || _statusMessage!.contains("错误") ? Colors.redAccent : Colors.white70,
                          ),
                          textAlign: TextAlign.center,
                        ),
                      ),
                  ],
                ),
              ),
            ),
          ),
        ],
      ),
    );
  }
}