import 'package:flutter/material.dart';
import 'package:intl/intl.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/large_app_bar.dart';

import '../../../widgets/birthday_selector.dart';

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

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

    Map<String, dynamic> data = {
      'birth_day': DateFormat('yyyy-MM-dd')
          .parseUTC(viewModel.selectedBirthday ?? DateTime.now().toString())
          .toIso8601String()
    };
    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,
        _buildBirthdayFormField(viewModel)
      ];

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

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

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

  Widget _buildBirthdayFormField(OnboardingViewModel viewModel) =>
      BirthdaySelector(
        birthday: viewModel.selectedBirthday,
        onSelected: (value) =>
            viewModel.setBirthday(DateFormat('yyyy-MM-dd').format(value)),
      );

  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.selectedBirthday != null
            ? kcPrimaryColor
            : kcPrimaryColor.withOpacity(0.1),
        onTap:
            viewModel.selectedBirthday != null ? () => _next(viewModel) : null,
      );
}