// 首启个人信息保护同意闸（个保法 + App Store 中国区审核 5.1.1）。
//
// 移动端（iOS/Android）首次启动时全屏遮罩弹出：说明收集范围 + 可点
// 《隐私政策》《用户协议》+ 同意/不同意。同意持久化（SharedPreferences）
// 后不再出现；不同意时 Android 退出应用，iOS 留在弹层并提示（苹果 HIG
// 禁止程序性退出）。桌面与 Web 完全不弹。
// 挂载点：MaterialApp.router 的 builder（覆盖全部路由，早于登录页交互）。
import 'package:flutter/foundation.dart' show kIsWeb;
import 'dart:io' show Platform;

import 'package:flutter/gestures.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:url_launcher/url_launcher.dart';

import '../core/config/app_info.dart';
import '../core/config/store_compliance.dart';
import '../core/theme/app_dims.g.dart';
import '../core/theme/context_tokens.dart';
import 'ds/ds_atoms.dart';

const _kConsentKey = 'privacy_consent_v1';

class PrivacyConsentGate extends StatefulWidget {
  final Widget child;
  const PrivacyConsentGate({super.key, required this.child});

  @override
  State<PrivacyConsentGate> createState() => _PrivacyConsentGateState();
}

class _PrivacyConsentGateState extends State<PrivacyConsentGate> {
  bool _needConsent = false;
  bool _declinedHint = false;

  @override
  void initState() {
    super.initState();
    if (needsPrivacyConsent) _check();
  }

  Future<void> _check() async {
    final prefs = await SharedPreferences.getInstance();
    if (mounted && !(prefs.getBool(_kConsentKey) ?? false)) {
      setState(() => _needConsent = true);
    }
  }

  Future<void> _agree() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.setBool(_kConsentKey, true);
    if (mounted) setState(() => _needConsent = false);
  }

  void _decline() {
    // Android 惯例：不同意即退出；iOS 禁止程序性退出，留提示。
    if (!kIsWeb && Platform.isAndroid) {
      SystemNavigator.pop();
    } else {
      setState(() => _declinedHint = true);
    }
  }

  void _open(String path) {
    final base = AppInfo.website.isNotEmpty
        ? AppInfo.website
        : 'https://jiu.51yanmei.com';
    launchUrl(Uri.parse('$base$path'), mode: LaunchMode.externalApplication);
  }

  @override
  Widget build(BuildContext context) {
    if (!_needConsent) return widget.child;
    final t = context.tokens;
    final link = TextStyle(
        fontSize: AppDims.fsSm, color: t.primary, fontWeight: FontWeight.w600);
    return Stack(children: [
      widget.child,
      const ModalBarrier(
          dismissible: false, color: Colors.black54), // ds-ignore 遮罩固定色
      Center(
        child: Material(
          color: Colors.transparent,
          child: Container(
            width: 320,
            margin: const EdgeInsets.symmetric(horizontal: 24),
            padding: const EdgeInsets.fromLTRB(22, 22, 22, 18),
            decoration: BoxDecoration(
              color: t.surface,
              borderRadius: BorderRadius.circular(AppDims.rLg),
              border: Border.all(color: t.border),
            ),
            child: Column(mainAxisSize: MainAxisSize.min, children: [
              Text('个人信息保护提示',
                  style: TextStyle(
                      fontSize: AppDims.fsH2,
                      fontWeight: FontWeight.w700,
                      color: t.heading)),
              const SizedBox(height: 12),
              Text.rich(
                TextSpan(
                  style: TextStyle(
                      fontSize: AppDims.fsSm, color: t.text, height: 1.7),
                  children: [
                    const TextSpan(
                        text: '感谢使用岩美酒库。为向您提供门店库存管理服务，'
                            '我们仅收集必要的账号信息、设备信息与操作日志，'
                            '用于多端数据同步与账号安全保障。详情请阅读'),
                    TextSpan(
                        text: '《隐私政策》',
                        style: link,
                        recognizer: TapGestureRecognizer()
                          ..onTap = () => _open('/privacy/')),
                    const TextSpan(text: '与'),
                    TextSpan(
                        text: '《用户协议》',
                        style: link,
                        recognizer: TapGestureRecognizer()
                          ..onTap = () => _open('/terms/')),
                    const TextSpan(text: '。点击「同意并继续」即表示您已阅读并同意上述条款。'),
                  ],
                ),
              ),
              if (_declinedHint) ...[
                const SizedBox(height: 10),
                Text('需同意后方可使用岩美酒库',
                    style: TextStyle(fontSize: AppDims.fsXs, color: t.warn)),
              ],
              const SizedBox(height: 16),
              Row(children: [
                Expanded(
                    child: DsButton('不同意', onPressed: _decline)),
                const SizedBox(width: 10),
                Expanded(
                    child: DsButton('同意并继续',
                        variant: DsBtnVariant.primary, onPressed: _agree)),
              ]),
            ]),
          ),
        ),
      ),
    ]);
  }
}