selfprivacy.org.app/lib/ui/pages/server/select_timezone.dart

part of 'server_settings.dart';

final List<Location> locations = timeZoneDatabase.locations.values.toList()
  ..sort(
    (final l1, final l2) =>
        l1.currentTimeZone.offset.compareTo(l2.currentTimeZone.offset),
  );

@RoutePage()
class SelectTimezonePage extends StatefulWidget {
  const SelectTimezonePage({super.key});

  @override
  State<SelectTimezonePage> createState() => _SelectTimezonePageState();
}

class _SelectTimezonePageState extends State<SelectTimezonePage> {
  final ScrollController scrollController = ScrollController();
  final TextEditingController searchController = TextEditingController();

  String? timezoneFilterValue;
  bool isSearching = false;

  @override
  void initState() {
    WidgetsBinding.instance.addPostFrameCallback(_afterLayout);
    searchController.addListener(() {
      setState(() {
        timezoneFilterValue =
            searchController.text.isNotEmpty ? searchController.text : null;
      });
    });
    super.initState();
  }

  void _afterLayout(final _) {
    final t = DateTime.now().timeZoneOffset;
    final index = locations.indexWhere(
      (final element) =>
          Duration(milliseconds: element.currentTimeZone.offset) == t,
    );
    print(t);

    if (index >= 0) {
      scrollController.animateTo(
        60.0 * index,
        duration: const Duration(milliseconds: 300),
        curve: Curves.easeIn,
      );
    }
  }

  @override
  void dispose() {
    scrollController.dispose();
    searchController.dispose();
    super.dispose();
  }

  @override
  Widget build(final BuildContext context) {
    final isDesktop = Breakpoints.mediumAndUp.isActive(context);
    return Scaffold(
      appBar: AppBar(
        automaticallyImplyLeading: false,
        title: (isDesktop || isSearching)
            ? TextField(
                readOnly: false,
                textAlign: TextAlign.start,
                textInputAction: TextInputAction.next,
                enabled: true,
                controller: searchController,
                decoration: InputDecoration(
                  errorText: null,
                  hintText: 'server.timezone_search_bar'.tr(),
                ),
              )
            : Padding(
                padding: const EdgeInsets.only(top: 4.0),
                child: Text('server.select_timezone'.tr()),
              ),
        leading: !isDesktop
            ? IconButton(
                icon: const Icon(Icons.arrow_back),
                onPressed: isSearching
                    ? () => setState(() => isSearching = false)
                    : () => Navigator.of(context).pop(),
              )
            : null,
        actions: [
          if (!isSearching && !isDesktop)
            IconButton(
              icon: const Icon(Icons.search),
              onPressed: () => setState(() => isSearching = true),
            ),
        ],
      ),
      body: SafeArea(
        child: ListView(
          controller: scrollController,
          children: locations
              .where(
                (final Location location) => timezoneFilterValue == null
                    ? true
                    : location.name
                            .toLowerCase()
                            .contains(timezoneFilterValue!) ||
                        Duration(
                          milliseconds: location.currentTimeZone.offset,
                        )
                            .toTimezoneOffsetFormat()
                            .contains(timezoneFilterValue!),
              )
              .toList()
              .asMap()
              .map(
                (final key, final value) => locationToListTile(key, value),
              )
              .values
              .toList(),
        ),
      ),
    );
  }

  MapEntry<int, ListTile> locationToListTile(
    final int key,
    final Location location,
  ) {
    final duration = Duration(milliseconds: location.currentTimeZone.offset);
    final area = location.currentTimeZone.abbreviation
        .replaceAll(RegExp(r'[\d+()-]'), '');

    return MapEntry(
      key,
      ListTile(
        title: Text(
          location.name,
        ),
        subtitle: Text(
          'GMT ${duration.toTimezoneOffsetFormat()} ${area.isNotEmpty ? '($area)' : ''}',
        ),
        onTap: () {
          context.read<JobsCubit>().addJob(
                ChangeServerTimezoneJob(
                  timezone: location.name,
                ),
              );
          Navigator.of(context).pop();
        },
      ),
    );
  }
}