import 'package:flutter/material.dart';
import 'package:stacked/stacked.dart';
import 'package:yimaru_app/ui/common/app_colors.dart';
import 'package:yimaru_app/ui/common/ui_helpers.dart';
import 'package:yimaru_app/ui/widgets/custom_elevated_button.dart';
import 'package:yimaru_app/ui/views/onboarding/onboarding_viewmodel.dart';
import 'package:yimaru_app/ui/widgets/custom_small_radio_button.dart';
import 'package:yimaru_app/ui/widgets/large_app_bar.dart';

class GenderFormScreen extends ViewModelWidget<OnboardingViewModel> {
  const GenderFormScreen({super.key});

  Future<void> _next(OnboardingViewModel viewModel) async {
    FocusManager.instance.primaryFocus?.unfocus();

    Map<String, dynamic> data = {'gender': viewModel.selectedGender};
    viewModel.addUserData(data);

    viewModel.next();
  }

  @override
  Widget build(BuildContext context, OnboardingViewModel viewModel) =>
      _buildScaffoldWrapper(viewModel);

  Widget _buildScaffoldWrapper(OnboardingViewModel viewModel) => Scaffold(
        backgroundColor: kcBackgroundColor,
        body: _buildScaffold(viewModel),
      );

  Widget _buildScaffold(OnboardingViewModel viewModel) => Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: _buildScaffoldChildren(viewModel),
      );

  List<Widget> _buildScaffoldChildren(OnboardingViewModel viewModel) =>
      [_buildAppBar(viewModel), _buildExpandedBody(viewModel)];

  Widget _buildExpandedBody(OnboardingViewModel viewModel) =>
      Expanded(child: _buildBodyWrapper(viewModel));

  Widget _buildBodyWrapper(OnboardingViewModel viewModel) => Padding(
        padding: const EdgeInsets.symmetric(horizontal: 15),
        child: _buildBody(viewModel),
      );

  Widget _buildBody(OnboardingViewModel viewModel) => Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: _buildBodyChildren(viewModel),
      );

  List<Widget> _buildBodyChildren(OnboardingViewModel viewModel) =>
      [_buildUpperColumn(viewModel), _buildContinueButtonWrapper(viewModel)];

  Widget _buildUpperColumn(OnboardingViewModel viewModel) => Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: _buildUpperColumnChildren(viewModel),
      );

  List<Widget> _buildUpperColumnChildren(OnboardingViewModel viewModel) => [
        verticalSpaceMedium,
        _buildTitle(),
        verticalSpaceSmall,
        _buildSubTitle(),
        verticalSpaceMedium,
        _buildAgeGroups(viewModel)
      ];

  Widget _buildAppBar(OnboardingViewModel viewModel) => LargeAppBar(
        onPop: viewModel.pop,
        showBackButton: true,
        showLanguageSelection: true,
        onLanguage: () async => await viewModel.navigateToLanguage(),
      );

  Widget _buildTitle() => const Text(
        'Choose your gender?',
        style: TextStyle(
          fontSize: 25,
          color: kcDarkGrey,
          fontWeight: FontWeight.w600,
        ),
      );

  Widget _buildSubTitle() => const Text(
        'We’ll personalize your learning experience based on your gender.',
        style: TextStyle(color: kcMediumGrey),
      );

  Widget _buildAgeGroups(OnboardingViewModel viewModel) => ListView.builder(
        shrinkWrap: true,
        itemCount: viewModel.genders.length,
        physics: const NeverScrollableScrollPhysics(),
        itemBuilder: (context, index) => _buildAgeGroup(
          title: viewModel.genders[index],
          selected: viewModel.isSelectedGender(viewModel.genders[index]),
          onTap: () => viewModel.setSelectedGender(viewModel.genders[index]),
        ),
      );

  Widget _buildAgeGroup(
          {required String title,
          required bool selected,
          required GestureTapCallback onTap}) =>
      CustomSmallRadioButton(
        title: title,
        onTap: onTap,
        selected: selected,
      );

  Widget _buildContinueButtonWrapper(OnboardingViewModel viewModel) => Padding(
        padding: const EdgeInsets.only(bottom: 50),
        child: _buildContinueButton(viewModel),
      );

  Widget _buildContinueButton(OnboardingViewModel viewModel) =>
      CustomElevatedButton(
        height: 55,
        text: 'Continue',
        borderRadius: 12,
        foregroundColor: kcWhite,
        backgroundColor: viewModel.selectedGender != null
            ? kcPrimaryColor
            : kcPrimaryColor.withOpacity(0.1),
        onTap: viewModel.selectedGender != null ? () => _next(viewModel) : null,
      );
}