// 家长同意确认页面 — PIPL 第28条合规
//
// 未满 14 岁用户选择"学生"角色后，必须经过家长/监护人确认。
// 页面展示隐私政策要点，要求家长勾选同意并确认。

import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:go_router/go_router.dart';

import '../../../core/constants/design_tokens.dart';
import '../../../core/theme/app_radius.dart';
import '../bloc/auth_bloc.dart';

/// 家长同意确认页面
class ParentalConsentPage extends StatefulWidget {
  const ParentalConsentPage({super.key});

  @override
  State<ParentalConsentPage> createState() => _ParentalConsentPageState();
}

class _ParentalConsentPageState extends State<ParentalConsentPage> {
  bool _consentGiven = false;
  bool _privacyPolicyAccepted = false;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final canProceed = _consentGiven && _privacyPolicyAccepted;

    return Scaffold(
      backgroundColor: theme.colorScheme.surface,
      appBar: AppBar(
        title: const Text('家长/监护人确认'),
        backgroundColor: theme.colorScheme.surface,
      ),
      body: SafeArea(
        child: SingleChildScrollView(
          padding: const EdgeInsets.all(DesignTokens.spacing16),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              // 标题
              Icon(
                Icons.shield_rounded,
                size: 48,
                color: theme.colorScheme.primary,
              ),
              const SizedBox(height: DesignTokens.spacing12),
              Text(
                '儿童个人信息保护',
                style: theme.textTheme.headlineSmall?.copyWith(
                  fontWeight: FontWeight.bold,
                ),
              ),
              const SizedBox(height: DesignTokens.spacing8),
              Text(
                '根据《中华人民共和国个人信息保护法》第28条，'
                '未满14周岁未成年人的个人信息处理需要取得父母或监护人的同意。',
                style: theme.textTheme.bodyMedium?.copyWith(
                  color: theme.colorScheme.onSurfaceVariant,
                ),
              ),
              const SizedBox(height: DesignTokens.spacing24),

              // 信息收集说明卡片
              _buildInfoCard(
                context,
                icon: Icons.info_outline_rounded,
                title: '我们会收集哪些信息',
                items: const [
                  '昵称和年级（不收集真实姓名和身份证号）',
                  '日记内容和手写笔画',
                  '心情标签和照片',
                ],
              ),
              const SizedBox(height: DesignTokens.spacing12),

              // 用途说明卡片
              _buildInfoCard(
                context,
                icon: Icons.security_rounded,
                title: '信息如何保护',
                items: const [
                  '所有数据加密存储和传输',
                  '仅用于日记记录和班级互动',
                  '不会用于商业广告或分享给第三方',
                  '您可以随时查阅、更正或删除孩子数据',
                ],
              ),
              const SizedBox(height: DesignTokens.spacing24),

              // 同意复选框
              _buildCheckbox(
                value: _privacyPolicyAccepted,
                onChanged: (v) =>
                    setState(() => _privacyPolicyAccepted = v ?? false),
                text: '我已阅读并同意《暖记隐私政策》和《儿童个人信息保护规则》',
              ),
              const SizedBox(height: DesignTokens.spacing4),

              _buildCheckbox(
                value: _consentGiven,
                onChanged: (v) => setState(() => _consentGiven = v ?? false),
                text: '我是该用户的家长/监护人，同意暖记收集和处理上述信息',
              ),
              const SizedBox(height: DesignTokens.spacing32),

              // 确认按钮
              SizedBox(
                width: double.infinity,
                child: FilledButton(
                  onPressed: canProceed ? _onConfirm : null,
                  style: FilledButton.styleFrom(
                    padding: const EdgeInsets.symmetric(
                      vertical: DesignTokens.spacing12,
                    ),
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(AppRadius.pill),
                    ),
                  ),
                  child: const Text('确认同意，继续'),
                ),
              ),
              const SizedBox(height: DesignTokens.spacing8),

              // 拒绝按钮
              SizedBox(
                width: double.infinity,
                child: OutlinedButton(
                  onPressed: () => context.pop(),
                  style: OutlinedButton.styleFrom(
                    padding: const EdgeInsets.symmetric(
                      vertical: DesignTokens.spacing12,
                    ),
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(AppRadius.pill),
                    ),
                  ),
                  child: const Text('不同意，返回'),
                ),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Widget _buildInfoCard(
    BuildContext context, {
    required IconData icon,
    required String title,
    required List<String> items,
  }) {
    final theme = Theme.of(context);
    return Card(
      elevation: 0,
      color: theme.colorScheme.surfaceContainerLow,
      shape: RoundedRectangleBorder(
        borderRadius: BorderRadius.circular(AppRadius.lg),
      ),
      child: Padding(
        padding: const EdgeInsets.all(DesignTokens.spacing12),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Icon(icon, size: 20, color: theme.colorScheme.primary),
                const SizedBox(width: DesignTokens.spacing8),
                Text(
                  title,
                  style: theme.textTheme.titleSmall?.copyWith(
                    fontWeight: FontWeight.w600,
                  ),
                ),
              ],
            ),
            const SizedBox(height: DesignTokens.spacing8),
            ...items.map(
              (item) => Padding(
                padding: const EdgeInsets.only(
                  bottom: DesignTokens.spacing4,
                  left: DesignTokens.spacing12,
                ),
                child: Row(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '• ',
                      style: theme.textTheme.bodySmall?.copyWith(
                        color: theme.colorScheme.primary,
                      ),
                    ),
                    Expanded(
                      child: Text(
                        item,
                        style: theme.textTheme.bodySmall,
                      ),
                    ),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildCheckbox({
    required bool value,
    required ValueChanged<bool?> onChanged,
    required String text,
  }) {
    final theme = Theme.of(context);
    return InkWell(
      onTap: () => onChanged(!value),
      borderRadius: BorderRadius.circular(AppRadius.md),
      child: Padding(
        padding: const EdgeInsets.symmetric(
          vertical: DesignTokens.spacing4,
        ),
        child: Row(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Checkbox(
              value: value,
              onChanged: onChanged,
              materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
            ),
            const SizedBox(width: DesignTokens.spacing4),
            Expanded(
              child: Padding(
                padding: const EdgeInsets.only(top: 12),
                child: Text(
                  text,
                  style: theme.textTheme.bodySmall,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  /// 确认同意 — 发出事件继续注册流程
  void _onConfirm() {
    final consentAt = DateTime.now();
    context.read<AuthBloc>().add(ParentalConsentAccepted(consentAt));
  }
}