import 'package:eatvio_app/core/utils/image_constant.dart';
import 'package:eatvio_app/core/widgets/loader.dart';
import 'package:eatvio_app/features/registration/presentation/bloc/registration_cubit/registration_cubit.dart';
import 'package:eatvio_app/features/registration/presentation/bloc/registration_cubit/registration_state.dart';
import 'package:eatvio_app/features/registration/presentation/pages/additional_information_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/allergies_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/blood_pressure_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/body_circumferences_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/city_of_living_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/credentials_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/date_of_birth_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/favorite_foods_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/favorite_sports_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/gender_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/height_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/medicine_intake_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/name_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/phone_screen.dart';
import 'package:eatvio_app/features/registration/presentation/pages/weight_screen.dart';
import 'package:eatvio_app/generated/l10n.dart';
import 'package:eatvio_app/core/locator_service.dart';
import 'package:eatvio_app/core/theme/theme_helper.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:flutter_svg/flutter_svg.dart';
import 'package:go_router/go_router.dart';
import 'package:validators/validators.dart';

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

  @override
  State<RegistrationScreen> createState() => _RegistrationScreenState();
}

class _RegistrationScreenState extends State<RegistrationScreen> {
  double progressValue = 1 / 15;
  int step = 1;
  final pageController = PageController();
  final RegistrationCubit registrationCubit = sl<RegistrationCubit>();

  @override
  Widget build(BuildContext context) {
    return BlocProvider<RegistrationCubit>(
      create: (BuildContext context) => registrationCubit,
      child: BlocBuilder<RegistrationCubit, RegistrationState>(
        builder: (BuildContext context, RegistrationState state) {
          return Scaffold(
            floatingActionButtonLocation: FloatingActionButtonLocation.centerFloat,
            floatingActionButton: Row(
              children: [
                Container(
                  height: 48,
                  width: MediaQuery.of(context).size.width * 0.2,
                  padding: EdgeInsets.only(left: 16, right: 4),
                  child: FloatingActionButton.extended(
                    heroTag: 'backButtonRegistration',
                    highlightElevation: 0,
                    focusElevation: 0,
                    elevation: 0,
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(20),
                    ),
                    backgroundColor: Color(0xFFEAF2FD),
                    onPressed: () async {
                      setState(() {
                        pageController.previousPage(
                          duration: const Duration(milliseconds: 350),
                          curve: Curves.easeInOut,
                        );
                      });
                    },
                    label: Icon(
                      Icons.arrow_back_ios_new_rounded,
                      color: appTheme.blueA400,
                    ),
                  ),
                ),
                Container(
                  height: 48,
                  width: MediaQuery.of(context).size.width * 0.8,
                  padding: EdgeInsets.only(left: 4, right: 16),
                  child: FloatingActionButton.extended(
                    heroTag: 'nextButtonRegistration',
                    highlightElevation: 0,
                    elevation: 0,
                    focusElevation: 0,
                    shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.circular(20),
                    ),
                    backgroundColor: appTheme.blueA400,
                    onPressed: () async {
                      if (await canGoNext(state)) {
                        setState(() {
                          pageController.nextPage(
                            duration: const Duration(milliseconds: 350),
                            curve: Curves.easeInOut,
                          );
                        });
                      }
                    },
                    label: Text(
                      'Продолжить',
                      style: theme.textTheme.titleSmall!.copyWith(color: Colors.white),
                    ),
                  ),
                ),
              ],
            ),
            appBar: AppBar(
              automaticallyImplyLeading: false,
              leading: Builder(
                builder: (context) => IconButton(
                  icon: Icon(Icons.close_rounded),
                  onPressed: () => GoRouter.of(context).pop(),
                ),
              ),
              centerTitle: true,
              title: SvgPicture.asset(
                ImageConstant.imgLogoEatvio,
                height: 48,
                fit: BoxFit.contain,
              ),
              actions: [
                Padding(
                  padding: const EdgeInsets.only(right: 16),
                  child: Text('шаг $step из 15'),
                ),
              ],
              bottom: PreferredSize(
                preferredSize: Size(MediaQuery.of(context).size.width, 32),
                child: Padding(
                  padding: const EdgeInsets.all(16),
                  child: TweenAnimationBuilder<double>(
                    duration: const Duration(milliseconds: 350),
                    curve: Curves.easeInOut,
                    tween: Tween<double>(
                      begin: 1 / 15,
                      end: progressValue,
                    ),
                    builder: (context, value, _) => LinearProgressIndicator(
                      value: value,
                      borderRadius: BorderRadius.circular(16),
                      minHeight: 8,
                      backgroundColor: Colors.grey.shade100,
                      valueColor: AlwaysStoppedAnimation<Color>(appTheme.blueA400),
                    ),
                  ),
                ),
              ),
            ),
            body: PageView(
              physics: NeverScrollableScrollPhysics(),
              controller: pageController,
              onPageChanged: (index) {
                setState(() {
                  step = index + 1;
                  progressValue = step / 15;
                });
              },
              children: [
                // LanguageSelectScreen(sheet: state.sheet),
                PhoneScreen(sheet: state.sheet),
                CredentialsScreen(sheet: state.sheet),
                NameScreen(sheet: state.sheet),
                GenderScreen(sheet: state.sheet),
                DateOfBirthScreen(sheet: state.sheet),
                CityOfLivingScreen(sheet: state.sheet),
                BodyCircumferencesScreen(sheet: state.sheet),
                WeightScreen(sheet: state.sheet),
                HeightScreen(sheet: state.sheet),
                BloodPressureScreen(sheet: state.sheet),
                AllergiesScreen(sheet: state.sheet),
                MedicineIntakeScreen(sheet: state.sheet),
                FavoriteSportsScreen(sheet: state.sheet),
                FavoriteFoodsScreen(sheet: state.sheet),
                AdditionalInformationScreen(sheet: state.sheet),
              ],
            ),
          );
        },
      ),
    );
  }

  Future<bool> canGoNext(RegistrationState state) async {
    switch (step) {
      case 1:
        if (state.sheet.phone.length != 18) {
          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text('Введите корректный номер телефона'),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        } else {
          return true;
        }
      case 2:
        List<String> errors = validateCredentialsFields(
          state.sheet.email,
          state.sheet.password,
          state.sheet.passwordConfirmation,
          context,
        );
        if (errors.isEmpty) {
          return true;
        } else {
          String errorMessage = '';

          for (var error in errors) {
            errorMessage += error + '\n\n';
          }

          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text(errorMessage),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        }
      case 3:
        List<String> errors = validateNameFields(
          state.sheet.firstName.toString(),
          state.sheet.lastName.toString(),
          context,
        );
        if (errors.isEmpty) {
          return true;
        } else {
          String errorMessage = '';

          for (var error in errors) {
            errorMessage += error + '\n\n';
          }

          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text(errorMessage),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        }
      case 4:
        if (state.sheet.gender.isNotEmpty)
          return true;
        else {
          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text('Выберете пол'),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        }
      case 6:
        if (state.sheet.location.isNotEmpty)
          return true;
        else {
          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text('Заполните все поля'),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        }
      case 7:
        List<String> errors = validateCircumferencesFields(
          state.sheet.chestCircumference.toString(),
          state.sheet.waistCircumference.toString(),
          state.sheet.hipCircumference.toString(),
          context,
        );
        if (errors.isEmpty) {
          return true;
        } else {
          String errorMessage = '';

          for (var error in errors) {
            errorMessage += error + '\n\n';
          }

          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка'),
              content: Text(errorMessage),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(context),
                  child: Text('OK'),
                ),
              ],
            ),
          );
          return false;
        }
      case 15:
        try {
          showDialog(
            barrierDismissible: false,
            useSafeArea: false,
            context: context,
            builder: (context) => PopScope(
              canPop: false,
              child: const Loader(),
            ),
          );
          await registrationCubit.tryRegistration();
          Navigator.pop(context);
        } catch (e) {
          Navigator.pop(context);
          showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: Text('Ошибка при попытке регистрации'),
            ),
          );
        }
        return false;
      default:
        return true;
    }
  }

  List<String> validateCircumferencesFields(
    String chestCircumference,
    String waistCircumference,
    String hipCircumference,
    BuildContext context,
  ) {
    final s = S.of(context);

    List<String> errors = [];

    if (chestCircumference.isEmpty | waistCircumference.isEmpty | hipCircumference.isEmpty) {
      errors.add(s.circumference_empty);
    }

    if (![chestCircumference, waistCircumference, hipCircumference].every((circumference) => int.tryParse(circumference) != null)) {
      errors.add(s.circumference_is_not_a_number);
    }

    return errors;
  }

  List<String> validateCredentialsFields(
    String email,
    String password,
    String passwordConfirmation,
    BuildContext context,
  ) {
    final s = S.of(context);

    List<String> errors = [];

    if (!isEmail(email)) {
      errors.add(s.email_invalid);
    }

    if (email.isEmpty) {
      errors.add(s.email_empty);
    }

    if (password.length < 6) {
      errors.add(s.password_short);
    }

    if (password != passwordConfirmation) {
      errors.add(s.password_confirmation_mismatch);
    }

    return errors;
  }

  List<String> validateNameFields(
    String firstName,
    String lastName,
    BuildContext context,
  ) {
    List<String> errors = [];

    if (firstName.isEmpty) {
      errors.add('First name cannot be empty');
    }

    if (firstName.length < 1) {
      errors.add('First name is too short');
    }

    if (lastName.isEmpty) {
      errors.add('Last name cannot be empty');
    }

    if (lastName.length < 1) {
      errors.add('Last name is too short');
    }

    return errors;
  }
}