import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_svg/svg.dart';
import 'package:proxibuy/presentation/auth/bloc/auth_bloc.dart';
import 'package:proxibuy/presentation/pages/user_info_page.dart';
import '../../core/config/app_colors.dart';
import '../../core/gen/assets.gen.dart';
import '../utils/otp_timer_helper.dart';


class OtpPage extends StatefulWidget {
  final String phoneNumber;
  final String phone;
  final String countryCode;

  const OtpPage({
    super.key,
    required this.phoneNumber,
    required this.phone,
    required this.countryCode,
  });

  @override
  State<OtpPage> createState() => _OtpPageState();
}

class _OtpPageState extends State<OtpPage> {
  final List<FocusNode> _focusNodes = List.generate(5, (_) => FocusNode());
  final List<TextEditingController> _controllers = List.generate(
    5,
    (_) => TextEditingController(),
  );
  late final OtpTimerHelper _otpTimer;

  bool _hasError = false;
  String? _errorMessage;
  bool _isOtpComplete = false;

  @override
  void initState() {
    super.initState();
    _otpTimer = OtpTimerHelper()..startTimer();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      FocusScope.of(context).requestFocus(_focusNodes[0]);
    });
  }

  @override
  void dispose() {
    for (final node in _focusNodes) {
      node.dispose();
    }
    for (final controller in _controllers) {
      controller.dispose();
    }
    _otpTimer.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final textTheme = Theme.of(context).textTheme;

    return Directionality(
      textDirection: TextDirection.rtl,
      child: Scaffold(
        body: SafeArea(
          child: SingleChildScrollView(
            padding: const EdgeInsets.symmetric(horizontal: 24, vertical: 16),
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Center(child: Assets.icons.logo.svg(height: 160)),
                const SizedBox(height: 40),
                Text(
                  "کد یکبار مصرف",
                  style: textTheme.headlineMedium?.copyWith(
                    fontWeight: FontWeight.bold,
                  ),
                ),
                const SizedBox(height: 12),
                Text.rich(
                  TextSpan(
                    style: textTheme.titleMedium?.copyWith(
                      color: Colors.grey,
                      height: 1.5,
                    ),
                    children: <TextSpan>[
                      const TextSpan(
                        text: 'کد تایید به شماره ',
                        style: TextStyle(fontSize: 15),
                      ),
                      TextSpan(
                        text: widget.phoneNumber,
                        style: const TextStyle(
                          fontWeight: FontWeight.bold,
                          fontSize: 15,
                        ),
                      ),
                      const TextSpan(
                        text: ' ارسال شد.',
                        style: TextStyle(fontSize: 15),
                      ),
                    ],
                  ),
                  textDirection: TextDirection.rtl,
                ),
                SizedBox(height: 15),
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    SvgPicture.asset(Assets.icons.vector.path),
                    const SizedBox(width: 4),
                    TextButton(
                      onPressed: () => Navigator.of(context).pop(),
                      child: const Text(
                        "ویرایش شماره همراه",
                        style: TextStyle(color: AppColors.active),
                      ),
                    ),
                  ],
                ),
                const SizedBox(height: 15),
                _buildOtpFields(),
                const SizedBox(height: 15),
                if (_errorMessage != null)
                  Padding(
                    padding: const EdgeInsets.only(bottom: 16.0),
                    child: Center(
                      child: Text(
                        _errorMessage!,
                        style: const TextStyle(
                          color: Colors.red,
                          fontWeight: FontWeight.bold,
                        ),
                      ),
                    ),
                  )
                else
                  const SizedBox(height: 32),

                BlocConsumer<AuthBloc, AuthState>(
                  listener: (context, state) {
                    if (state is AuthFailure) {
                      setState(() {
                        _hasError = true;
                        _errorMessage = state.message;
                      });
                    }
                    if (state is AuthNeedsInfo) {
                      Navigator.of(context).pushAndRemoveUntil(
                        MaterialPageRoute(builder: (_) => const UserInfoPage()),
                        (route) => false,
                      );
                    }
                  },
                  builder: (context, state) {
                    bool isLoading = state is AuthLoading;
                    if (state is AuthLoading) {
                      return const Center(child: CircularProgressIndicator());
                    }
                    return SizedBox(
                      width: double.infinity,
                      height: 60,
                      child: ElevatedButton(
                        onPressed:
                            (_isOtpComplete && !isLoading) ? _verifyOtp : null,
                        child:
                            isLoading
                                ? const CircularProgressIndicator(
                                  color: Colors.white,
                                  strokeWidth: 3,
                                )
                                : const Text("ورود"),
                      ),
                    );
                  },
                ),
                const SizedBox(height: 32),
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    SvgPicture.asset(
                      Assets.icons.clock.path,
                      colorFilter: const ColorFilter.mode(
                        Colors.grey,
                        BlendMode.srcIn,
                      ),
                    ),
                    const SizedBox(width: 8),
                    ValueListenableBuilder<bool>(
                      valueListenable: _otpTimer.canResend,
                      builder: (context, canResend, child) {
                        return canResend
                            ? TextButton(
                              onPressed: _resendOtp,
                              child: const Text(
                                "ارسال مجدد کد",
                                style: TextStyle(color: AppColors.active),
                              ),
                            )
                            : ValueListenableBuilder<int>(
                              valueListenable: _otpTimer.remainingSeconds,
                              builder:
                                  (context, seconds, child) => Text(
                                    "${_otpTimer.formatTime()} تا دریافت مجدد",
                                    style: const TextStyle(color: Colors.grey),
                                  ),
                            );
                      },
                    ),
                  ],
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }

  Widget _buildOtpFields() {
    return Directionality(
      textDirection: TextDirection.ltr,
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: List.generate(5, (index) {
          return SizedBox(
            width: 60,
            height: 60,
            child: TextField(
              controller: _controllers[index],
              focusNode: _focusNodes[index],
              keyboardType: TextInputType.number,
              textAlign: TextAlign.center,
              maxLength: 1,
              style: TextStyle(
                fontSize: 22,
                fontWeight: FontWeight.bold,
                color: _hasError ? Colors.red : Colors.black,
              ),
              decoration: InputDecoration(
                counterText: '',
                enabledBorder: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(12),
                  borderSide: BorderSide(
                    color:
                        _hasError
                            ? Colors.red
                            : (Theme.of(context)
                                    .inputDecorationTheme
                                    .enabledBorder
                                    ?.borderSide
                                    .color ??
                                Colors.grey),
                  ),
                ),
                focusedBorder: OutlineInputBorder(
                  borderRadius: BorderRadius.circular(12),
                  borderSide: BorderSide(
                    color: _hasError ? Colors.red : AppColors.active,
                    width: 2,
                  ),
                ),
              ),
              onChanged: (value) {
                if (_hasError) {
                  setState(() {
                    _hasError = false;
                    _errorMessage = null;
                  });
                }
                if (value.length == 1 && index < 4) {
                  FocusScope.of(context).requestFocus(_focusNodes[index + 1]);
                }
                if (value.isEmpty && index > 0) {
                  FocusScope.of(context).requestFocus(_focusNodes[index - 1]);
                }
                final otpCode = _controllers.map((c) => c.text).join();
                setState(() {
                  _isOtpComplete = otpCode.length == 5;
                });
              },
            ),
          );
        }),
      ),
    );
  }

  void _verifyOtp() {
    final otpCode = _controllers.map((c) => c.text).join();
    if (otpCode.length == 5) {
      context.read<AuthBloc>().add(
        VerifyOTPEvent(
          otp: otpCode,
          phoneNumber: widget.phone,
          countryCode: widget.countryCode,
        ),
      );
    }
  }

  void _resendOtp() {
    for (var controller in _controllers) {
      controller.clear();
    }
    FocusScope.of(context).requestFocus(_focusNodes[0]);
    setState(() => _isOtpComplete = false);

    context.read<AuthBloc>().add(
      SendOTPEvent(phoneNumber: widget.phone, countryCode: widget.countryCode),
    );
    _otpTimer.resetTimer();
  }
}