import 'dart:io';

import 'package:country/country.dart' as country;
import 'package:dash_flags/dash_flags.dart' as country_flags;
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:karing/app/modules/setting_manager.dart';
import 'package:karing/i18n/strings.g.dart';
import 'package:karing/screens/theme_config.dart';
import 'package:karing/screens/theme_define.dart';
import 'package:karing/screens/widgets/framework.dart';
import 'package:karing/screens/widgets/text_field.dart';

class RegionSettingsScreen extends LasyRenderingStatefulWidget {
  static RouteSettings routSettings() {
    return const RouteSettings(name: "RegionSettingsScreen");
  }

  final bool canPop;
  final bool? canGoBack;
  final String? nextText;

  const RegionSettingsScreen({
    super.key,
    required this.canPop,
    required this.canGoBack,
    this.nextText,
  });

  @override
  State<RegionSettingsScreen> createState() => _RegionSetingsScreenState();
}

class _RegionSetingsScreenState
    extends LasyRenderingState<RegionSettingsScreen> {
  final FocusNode _focusNodeNext = FocusNode();
  List<country.Country> _searchedData = [];
  country.Country? _currentCountry;
  final Map<String, bool> _countriesAssets = {};

  final _searchController = TextEditingController();

  @override
  void initState() {
    super.initState();
    _initAssets();
  }

  @override
  void dispose() {
    _focusNodeNext.dispose();
    _searchController.dispose();
    super.dispose();
    SettingManager.save();
  }

  Future<void> _initAssets() async {
    if (Platform.isWindows) {
      for (var region in country.Countries.values) {
        var c = country_flags.Country.fromCode(region.alpha2);
        String asset =
            "packages/dash_flags/assets/svgs/flags/countries/country_${c.name}.svg";
        try {
          await rootBundle.load(asset);
          _countriesAssets[c.name] = true;
        } catch (e) {
          break;
        }
      }
    } else {
      for (var region in country.Countries.values) {
        var c = country_flags.Country.fromCode(region.alpha2);
        _countriesAssets[c.name] = true;
      }
    }

    _searchedData = country.Countries.values;
    _currentCountry = SettingManager.getConfig().currentCountry();
    if (!mounted) {
      return;
    }
    setState(() {});
  }

  Future<void> _loadSearch(String? textVal) async {
    if (_countriesAssets.isEmpty) {
      return;
    }
    if (textVal == null || textVal.isEmpty) {
      _searchedData = country.Countries.values;
      setState(() {});
    } else {
      textVal = textVal.toUpperCase();
      final data = country.Countries.values.where((country) {
        if (country.alpha2.startsWith(textVal!) ||
            country.alpha3.startsWith(textVal)) {
          return true;
        }

        var name =
            country.isoShortNameByLocale[SettingConfig.languageTagForCountry()];
        if (name != null) {
          return name.toUpperCase().startsWith(textVal);
        }
        return false;
      }).toList();
      _searchedData = data;
      setState(() {});
    }
  }

  _clearSearch() {
    if (_countriesAssets.isEmpty) {
      return;
    }
    _searchController.clear();
    _searchedData = country.Countries.values;
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    final tcontext = Translations.of(context);
    Size windowSize = MediaQuery.of(context).size;
    var setting = SettingManager.getConfig();
    return PopScope(
      canPop: widget.canPop,
      child: Scaffold(
        appBar: PreferredSize(preferredSize: Size.zero, child: AppBar()),
        body: Focus(
          onKeyEvent: onKeyEvent,
          canRequestFocus: false,
          skipTraversal: true,
          child: SafeArea(
            child: Padding(
              padding: const EdgeInsets.fromLTRB(0, 20, 0, 0),
              child: Column(
                children: [
                  Padding(
                    padding: const EdgeInsets.fromLTRB(0, 0, 0, 0),
                    child: Row(
                      mainAxisAlignment: MainAxisAlignment.spaceBetween,
                      children: [
                        widget.canGoBack == true
                            ? InkWell(
                                onTap: () => Navigator.pop(context),
                                child: const SizedBox(
                                  width: 50,
                                  height: 30,
                                  child: Icon(
                                    Icons.arrow_back_ios_outlined,
                                    size: 26,
                                  ),
                                ),
                              )
                            : const SizedBox(width: 50, height: 30),
                        SizedBox(
                          width: windowSize.width - 50 - 65,
                          child: Text(
                            tcontext.RegionSettingsScreen.title,
                            textAlign: TextAlign.center,
                            overflow: TextOverflow.ellipsis,
                            style: const TextStyle(
                              fontWeight: ThemeConfig.kFontWeightTitle,
                              fontSize: ThemeConfig.kFontSizeTitle,
                            ),
                          ),
                        ),
                        widget.nextText != null
                            ? SizedBox(
                                width: 65,
                                height: 30,
                                child: InkWell(
                                  autofocus: setting.ui.tvMode,
                                  focusNode: _focusNodeNext,
                                  onTap: () {
                                    Navigator.pop(context);
                                  },
                                  child: Text(
                                    textAlign: TextAlign.center,
                                    widget.nextText ?? "",
                                    overflow: TextOverflow.ellipsis,
                                    style: const TextStyle(
                                      fontWeight:
                                          ThemeConfig.kFontWeightListItem,
                                      fontSize: ThemeConfig.kFontSizeListItem,
                                    ),
                                  ),
                                ),
                              )
                            : const SizedBox(width: 50),
                      ],
                    ),
                  ),
                  Container(
                    margin: const EdgeInsets.only(top: 10),
                    padding: const EdgeInsets.only(left: 15, right: 15),
                    height: 44,
                    width: double.infinity,
                    decoration: const BoxDecoration(
                      borderRadius: ThemeDefine.kBorderRadius,
                    ),
                    child: TextFieldEx(
                      controller: _searchController,
                      textInputAction: TextInputAction.done,
                      onChanged: _loadSearch,
                      decoration: InputDecoration(
                        border: InputBorder.none,
                        //focusedBorder: InputBorder.none,
                        icon: Icon(Icons.search_outlined),
                        labelText: tcontext.meta.search,
                        hintText: tcontext.meta.search,
                        suffixIcon: _searchController.text.isNotEmpty
                            ? IconButton(
                                icon: const Icon(Icons.clear_outlined),
                                onPressed: _clearSearch,
                              )
                            : null,
                      ),
                    ),
                  ),
                  const SizedBox(height: 10),
                  Padding(
                    padding: const EdgeInsets.fromLTRB(10, 0, 10, 0),
                    child: Text(
                      tcontext.RegionSettingsScreen.Regions,
                      style: const TextStyle(
                        fontSize: ThemeConfig.kFontSizeListSubItem,
                        fontWeight: ThemeConfig.kFontWeightListSubItem,
                      ),
                    ),
                  ),
                  const SizedBox(height: 10),
                  _currentCountry == null
                      ? const SizedBox(height: 10)
                      : Row(
                          children: [
                            const SizedBox(width: 5),
                            _flag(_currentCountry!.alpha2),
                            const SizedBox(width: 15),
                            Text(
                              _currentCountry!.alpha2,
                              style: TextStyle(
                                fontSize: ThemeConfig.kFontSizeGroupItem,
                              ),
                            ),
                            const SizedBox(width: 15),
                            Text(
                              _currentCountry!
                                      .isoShortNameByLocale[SettingConfig.languageTagForCountry()] ??
                                  "",
                              style: TextStyle(
                                fontSize: ThemeConfig.kFontSizeGroupItem,
                              ),
                            ),
                          ],
                        ),
                  const SizedBox(height: 15),
                  Expanded(child: _loadListView()),
                ],
              ),
            ),
          ),
        ),
      ),
    );
  }

  KeyEventResult onKeyEvent(FocusNode node, KeyEvent event) {
    if (event is KeyDownEvent) {
      switch (event.logicalKey) {
        case LogicalKeyboardKey.arrowRight:
          if (widget.nextText != null) {
            _focusNodeNext.requestFocus();
            return KeyEventResult.handled;
          }
      }
    }
    return KeyEventResult.ignored;
  }

  Widget _loadListView() {
    return Scrollbar(
      thumbVisibility: true,
      child: ListView.separated(
        itemCount: _searchedData.length,
        itemBuilder: (BuildContext context, int index) {
          var current = _searchedData[index];
          return createWidget(current);
        },
        separatorBuilder: (BuildContext context, int index) {
          return const Divider(height: 1, thickness: 0.3);
        },
      ),
    );
  }

  Widget _flag(String alpha2) {
    var c = country_flags.Country.fromCode(alpha2);
    if (_countriesAssets[c.name] == true) {
      return country_flags.CountryFlag(country: c, height: 30);
    }
    return const SizedBox(width: 30, height: 30);
  }

  Widget createWidget(country.Country current) {
    return Material(
      color:
          SettingManager.getConfig().regionCode.toUpperCase() == current.alpha2
          ? ThemeDefine.kColorBlue
          : null,
      borderRadius: ThemeDefine.kBorderRadius,
      child: InkWell(
        onTap: () {
          onTapItem(current);
        },
        child: Container(
          padding: const EdgeInsets.symmetric(horizontal: 10),
          width: double.infinity,
          height: ThemeConfig.kListItemHeight2,
          child: Row(
            children: [
              Row(
                children: [
                  Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          _flag(current.alpha2),
                          const SizedBox(width: 15),
                          Text(
                            current.alpha2,
                            style: TextStyle(
                              fontSize: ThemeConfig.kFontSizeGroupItem,
                            ),
                          ),
                          const SizedBox(width: 15),
                          Text(
                            current.isoShortNameByLocale[SettingConfig.languageTagForCountry()] ??
                                "",
                            style: TextStyle(
                              fontSize: ThemeConfig.kFontSizeGroupItem,
                            ),
                          ),
                        ],
                      ),
                    ],
                  ),
                ],
              ),
            ],
          ),
        ),
      ),
    );
  }

  void onTapItem(country.Country current) {
    SettingManager.getConfig().regionCode = current.alpha2;
    SettingManager.getConfig().dns.clientSubnet = "";
    SettingManager.getConfig().dns.clientSubnetLatestUpdate = "";

    if (widget.nextText != null) {
      _currentCountry = SettingManager.getConfig().currentCountry();
      setState(() {});
    } else {
      SettingManager.setDirty(true);
      Navigator.pop(context);
    }
  }
}
