import 'dart:async';

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

import '../../core/network/api_exception.dart';
import '../../core/storage/local_store.dart';
import '../../core/theme/app_theme.dart';
import '../../providers/auth_provider.dart';
import '../../services/auth_service.dart';

/// 注册页：手机号/邮箱 + 验证码 + 密码；邀请码选填（口令/模糊归因命中时自动预填）
class RegisterScreen extends ConsumerStatefulWidget {
  const RegisterScreen({super.key});

  @override
  ConsumerState<RegisterScreen> createState() => _RegisterScreenState();
}

class _RegisterScreenState extends ConsumerState<RegisterScreen> {
  final _account = TextEditingController();
  final _code = TextEditingController();
  final _password = TextEditingController();
  final _nickname = TextEditingController();
  late final TextEditingController _inviteCode;

  /// 注册方式：phone / email
  String _mode = 'phone';
  bool get _isEmail => _mode == 'email';

  bool _loading = false;
  String? _error;

  /// 验证码发送倒计时
  int _countdown = 0;
  Timer? _timer;

  /// 邮箱格式校验
  static final _emailReg = RegExp(r'^[\w.+-]+@[\w-]+\.[\w.-]+$');

  @override
  void initState() {
    super.initState();
    // 首启归因命中的邀请码预填（用户可改可清空）
    _inviteCode = TextEditingController(text: LocalStore.I.pendingInviteCode ?? '');
  }

  @override
  void dispose() {
    _timer?.cancel();
    _account.dispose();
    _code.dispose();
    _password.dispose();
    _nickname.dispose();
    _inviteCode.dispose();
    super.dispose();
  }

  void _switchMode(String mode) {
    if (mode == _mode) return;
    setState(() {
      _mode = mode;
      _error = null;
      // 切换方式后账号和验证码需要重新填写
      _account.clear();
      _code.clear();
    });
  }

  Future<void> _sendCode() async {
    final account = _account.text.trim();
    if (_isEmail) {
      if (!_emailReg.hasMatch(account)) {
        setState(() => _error = '请输入正确的邮箱地址');
        return;
      }
    } else {
      if (!RegExp(r'^1\d{10}$').hasMatch(account)) {
        setState(() => _error = '请输入正确的手机号');
        return;
      }
    }
    try {
      // 未配置短信/邮件通道时服务端走开发模式，直接返回验证码
      final devCode = _isEmail
          ? await AuthService.sendEmailCode(account, 'register')
          : await AuthService.sendSmsCode(account, 'register');
      setState(() {
        _error = null;
        _countdown = 60;
      });
      if (devCode != null && mounted) {
        // 通道未配置时的开发模式：直接展示验证码（上线配置后服务端不再返回）
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('开发模式验证码：$devCode（5 分钟内有效）'), duration: const Duration(seconds: 6)),
        );
      }
      _timer?.cancel();
      _timer = Timer.periodic(const Duration(seconds: 1), (t) {
        if (_countdown <= 1) {
          t.cancel();
          setState(() => _countdown = 0);
        } else {
          setState(() => _countdown -= 1);
        }
      });
    } on ApiException catch (e) {
      setState(() => _error = e.message);
    } catch (_) {
      setState(() => _error = '网络异常，请稍后重试');
    }
  }

  Future<void> _submit() async {
    final account = _account.text.trim();
    final code = _code.text.trim();
    final password = _password.text;
    if (account.isEmpty || code.isEmpty || password.isEmpty) {
      setState(() => _error = _isEmail ? '请填写邮箱、验证码和密码' : '请填写手机号、验证码和密码');
      return;
    }
    setState(() {
      _loading = true;
      _error = null;
    });
    try {
      final result = await AuthService.register(
        type: _mode,
        account: account,
        code: code,
        password: password,
        nickname: _nickname.text.trim(),
        inviteCode: _inviteCode.text.trim().toUpperCase(),
      );
      // 注册成功：pending 邀请码已被消费，清除本地标记
      await LocalStore.I.clearPendingInviteCode();
      await ref.read(authProvider.notifier).onLoginSuccess(result.user);
      if (!mounted) return;
      if (result.trialPlanName != null) {
        ScaffoldMessenger.of(context).showSnackBar(
          SnackBar(content: Text('注册成功，已赠送${result.trialPlanName}')),
        );
      }
      context.go('/home');
    } on ApiException catch (e) {
      setState(() => _error = e.message);
    } catch (_) {
      setState(() => _error = '网络异常，请稍后重试');
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('注册')),
      body: SafeArea(
        child: ListView(
          padding: const EdgeInsets.all(24),
          children: [
            const Text('创建账号', style: TextStyle(fontSize: 26, fontWeight: FontWeight.w700)),
            const SizedBox(height: 24),
            // 手机号 / 邮箱 切换
            _ModeSwitch(current: _mode, onChanged: _switchMode),
            const SizedBox(height: 24),
            TextField(
              controller: _account,
              keyboardType: _isEmail ? TextInputType.emailAddress : TextInputType.phone,
              decoration: InputDecoration(hintText: _isEmail ? '邮箱' : '手机号'),
            ),
            const SizedBox(height: 16),
            Row(
              children: [
                Expanded(
                  child: TextField(
                    controller: _code,
                    keyboardType: TextInputType.number,
                    decoration: InputDecoration(hintText: _isEmail ? '邮箱验证码' : '短信验证码'),
                  ),
                ),
                const SizedBox(width: 12),
                SizedBox(
                  width: 120,
                  child: OutlinedButton(
                    onPressed: _countdown > 0 ? null : _sendCode,
                    child: Text(_countdown > 0 ? '${_countdown}s 后重发' : '获取验证码'),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 16),
            TextField(
              controller: _password,
              obscureText: true,
              decoration: const InputDecoration(hintText: '密码（8-32 位，含字母和数字）'),
            ),
            const SizedBox(height: 16),
            TextField(
              controller: _nickname,
              decoration: const InputDecoration(hintText: '昵称（选填）'),
            ),
            const SizedBox(height: 16),
            TextField(
              controller: _inviteCode,
              textCapitalization: TextCapitalization.characters,
              decoration: const InputDecoration(hintText: '邀请码（选填）'),
            ),
            if (_error != null) ...[
              const SizedBox(height: 12),
              Text(_error!, style: const TextStyle(color: AppColors.primary, fontSize: 13)),
            ],
            const SizedBox(height: 24),
            ElevatedButton(
              onPressed: _loading ? null : _submit,
              child: _loading
                  ? const SizedBox(
                      height: 20,
                      width: 20,
                      child: CircularProgressIndicator(strokeWidth: 2),
                    )
                  : const Text('注册并登录'),
            ),
            const SizedBox(height: 16),
            TextButton(
              onPressed: () => context.pop(),
              child: const Text('已有账号？去登录', style: TextStyle(color: AppColors.textSecondary)),
            ),
          ],
        ),
      ),
    );
  }
}

/// 注册方式切换条（手机号 / 邮箱）
class _ModeSwitch extends StatelessWidget {
  const _ModeSwitch({required this.current, required this.onChanged});

  final String current;
  final ValueChanged<String> onChanged;

  @override
  Widget build(BuildContext context) {
    return Container(
      decoration: BoxDecoration(
        color: AppColors.surface,
        borderRadius: BorderRadius.circular(10),
      ),
      padding: const EdgeInsets.all(3),
      child: Row(
        children: [
          _tab(context, '手机号', 'phone'),
          _tab(context, '邮箱', 'email'),
        ],
      ),
    );
  }

  Widget _tab(BuildContext context, String label, String value) {
    final selected = current == value;
    return Expanded(
      child: GestureDetector(
        onTap: () => onChanged(value),
        child: Container(
          padding: const EdgeInsets.symmetric(vertical: 9),
          alignment: Alignment.center,
          decoration: BoxDecoration(
            color: selected ? Theme.of(context).scaffoldBackgroundColor : Colors.transparent,
            borderRadius: BorderRadius.circular(8),
          ),
          child: Text(
            label,
            style: TextStyle(
              fontSize: 14,
              fontWeight: selected ? FontWeight.w600 : FontWeight.w400,
              color: selected ? AppColors.textPrimary : AppColors.textSecondary,
            ),
          ),
        ),
      ),
    );
  }
}