import 'package:flutter/material.dart';
import 'package:flutter_dotenv/flutter_dotenv.dart';
import 'package:dynamic_color/dynamic_color.dart';
import 'package:sqflite_common_ffi/sqflite_ffi.dart'; //for testing on desktop

import 'dart:async';
import 'dart:io';

import 'api_handler.dart';
import 'transport_helper.dart';
import 'utilities.dart';

void main() async {
  await dotenv.load();
  const String dbName = "oeffimasterTransportDb";

  if (Platform.isLinux) {
    databaseFactory = databaseFactoryFfi; // for debugging and desktop test
  }
  DbHelper.initDb(dbName);
  runApp(const MyApp());
}

final _defaultLightScheme = ColorScheme.fromSeed(seedColor: Colors.yellow);
final _defaultDarkScheme = ColorScheme.fromSeed(
  seedColor: Colors.yellow,
  brightness: Brightness.dark,
);

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return DynamicColorBuilder(
      builder: (ColorScheme? lightDynamic, ColorScheme? darkDynamic) {
        return MaterialApp(
          theme: ThemeData(
            useMaterial3: true,
            colorScheme: lightDynamic ?? _defaultLightScheme,
          ),
          darkTheme: ThemeData(
            useMaterial3: true,
            colorScheme: darkDynamic ?? _defaultDarkScheme,
          ),
          themeMode: ThemeMode.system,
          home: const JourneyOverviewPage(),
          title: 'Oeffimaster',
        );
      },
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});
  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;
  //String API_KEY = ApiHandler.accessID;
  String API_KEY = "no telly";
  //Future<Map<String, dynamic>> ?id;
  List<Station> stationList = [];
  String id = '';

  // TODO :find a better way to show the list
  void showResult(Future<List<Station>> futureId) async {
    stationList = await futureId;
    id = stationList[0].id;
    setState(() {});
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        //backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        //backgroundColor: Colors.amber,
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: .center,
          children: [
            // const Text('You have pushed the button this many times:'),
            // Text(
            //   '$_counter',
            //   style: Theme.of(context).textTheme.headlineMedium,
            // ),
            // Text('API key from ENV is $API_KEY'),
            // MaterialButton(
            //   onPressed: () {
            //     showResult(ApiHandler.findStations('S Biesdorf'));
            //   },
            //   child: Text('Search for \'S Biesdorf\''),
            // ),
            // Text(id),
            ElevatedButton(
              onPressed: () {
                Navigator.push(
                  context,
                  MaterialPageRoute(builder: (context) => ChooseStationPage()),
                );
              },
              child: const Text('Start a route'),
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        backgroundColor: Theme.of(context).colorScheme.primaryContainer,
        foregroundColor: Theme.of(context).colorScheme.onPrimaryContainer,
        onPressed: () {
          Navigator.push(
            context,
            MaterialPageRoute(builder: (context) => ChooseStationPage()),
          );
        },
        tooltip: 'Start a route',
        child: const Icon(Icons.add),
      ),
    );
  }
}

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

  @override
  State<ChooseStationPage> createState() => _ChooseStationPageState();
}

class _ChooseStationPageState extends State<ChooseStationPage> {
  Station? _selectedStation;
  List<Station> stationList = [];
  Timer? _debounce;

  void findNearbyStations() async {
    stationList = await ApiHandler.nearbyStations(
      // TODO: replace with location
      "52.55",
      "13.55",
      maxStations: 20,
    );
  }

  void findStationsByName(
    String name, {
    int? resultnum,
  }) async {
    stationList = await ApiHandler.findStations(name);
  }

  void showResult(Future<List<Station>> futureId) async {
    stationList = await futureId;
    setState(() {});
  }

  // Source - https://stackoverflow.com/a/52930197
  // Posted by Jannie Theunissen, modified by community. See post 'Timeline' for change history
  // Retrieved 2026-07-30, License - CC BY-SA 4.0
  void _onSearchChanged(String? query) {
    if (_debounce?.isActive ?? false) _debounce?.cancel();
    _debounce = Timer(const Duration(milliseconds: 400), () {
      _search(query);
    });
  }

  void _search(String? query) {
    if (query?.isEmpty ?? true) return;
    // do something with query
    setState(() {
      findStationsByName(query!);
    });
  }

  @override
  void dispose() {
    _debounce?.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Start a Journey')),
      body: Center(
        child: Column(
          children: [
            // ElevatedButton(
            //   onPressed: () {
            //     showResult(ApiHandler.findStations('S Biesdorf'));
            //   },
            //   child: Text('Search for \'S Biesdorf\''),
            // ),
            SearchAnchor(
              builder: (BuildContext context, SearchController controller) {
                return SearchBar(
                  controller: controller,
                  hintText: 'Search your start Station',
                  padding: const WidgetStatePropertyAll<EdgeInsets>(
                    EdgeInsets.symmetric(horizontal: 16.0),
                  ),
                  // onTap: () {
                  //   controller.openView();
                  // },
                  onChanged: _onSearchChanged,
                  onSubmitted: _search,
                  leading: const Icon(Icons.search),
                );
              },
              suggestionsBuilder:
                  (BuildContext context, SearchController controller) {
                    return List<ListTile>.generate(5, (int index) {
                      final String item = 'item $index';
                      return ListTile(
                        title: Text(item),
                        onTap: () {
                          setState(() {
                            controller.closeView(item);
                          });
                        },
                      );
                    });
                  },
            ),
            Expanded(
              child: SizedBox(
                height: 200,
                child: StationList(
                  stationList: stationList,
                  onTapped: _handleStationTapped,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  void _handleStationTapped(Station station) {
    // setState(() {
    //   _selectedStation = station;
    // });
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => ChooseDeparturePage(startStation: station),
      ),
    );
  }
}

class StationList extends StatelessWidget {
  final List<Station> stationList;
  final ValueChanged<Station> onTapped;

  StationList({
    super.key,
    required this.stationList,
    required this.onTapped,
  });

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        for (Station station in stationList)
          ListTile(
            title: Text(station.name),
            onTap: () => onTapped(station),
          ),
      ],
    );
  }
}

class ChooseDeparturePage extends StatefulWidget {
  final Station startStation;
  final int? journeyId;
  final Departure? arrival;
  const ChooseDeparturePage({
    super.key,
    this.journeyId,
    this.arrival,
    required this.startStation,
  });

  @override
  State<ChooseDeparturePage> createState() => _ChooseDeparturePageState();
}

class _ChooseDeparturePageState extends State<ChooseDeparturePage> {
  List<Departure> departureList = [];
  Journey? singleJourney;

  void loadDepartures(Station startStation) async {
    departureList = await ApiHandler.departures(
      startStation.id,
      datetime: widget.arrival?.arrivalTime ?? DateTime.now(),
    );
    setState(() {});
  }

  void loadJourney(int journeyId) async {
    singleJourney = await Journey.dbGet(journeyId);
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => JourneyDetailPage(
          singleJourney: singleJourney as Journey,
        ),
      ),
    );
  }

  @override
  initState() {
    super.initState();
    loadDepartures(widget.startStation);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          'Departures for ${widget.startStation.name}',
        ),
      ),
      body: Center(
        child: Column(
          children: [
            Builder(
              builder: (context) {
                if (widget.arrival != null) {
                  return ListTile(
                    title: Text(
                      'arrive at ${widget.arrival?.arrivalTime}',
                    ),
                  );
                } else {
                  return ListTile(
                    title: Text(''),
                  );
                }
              },
            ),
            Expanded(
              child: SizedBox(
                height: 400,
                child: DepartureList(
                  departureList: departureList,
                  onTapped: _handleDepartureTapped,
                ),
              ),
            ),
            // ElevatedButton(
            //   onPressed: () {
            //     if (widget.journeyId != null) {
            //       loadJourney(widget.journeyId as int);
            //     }
            //   },
            //   child: const Text('Finish Route'),
            // ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        backgroundColor: Theme.of(context).colorScheme.primaryContainer,
        foregroundColor: Theme.of(context).colorScheme.onPrimaryContainer,
        onPressed: () {
          if (widget.journeyId != null) {
            loadJourney(widget.journeyId as int);
          }
        },
        tooltip: 'Finish route',
        child: const Icon(Icons.check),
      ),
    );
  }

  void _handleDepartureTapped(Departure departure) {
    // setState(() {
    //   _selectedDeparture = departure;
    // });
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => ChooseArrivalPage(
          departure: departure,
          journeyId: widget.journeyId,
        ),
      ),
    );
  }
}

class DepartureList extends StatelessWidget {
  final List<Departure> departureList;
  final ValueChanged<Departure> onTapped;

  const DepartureList({
    super.key,
    required this.departureList,
    required this.onTapped,
  });

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        for (Departure departure in departureList)
          ListTile(
            title: Text('${departure.vehicleName}: ${departure.direction}'),
            subtitle: Text(departure.departureTime.toString()),
            onTap: () => onTapped(departure),
          ),
      ],
    );
  }
}

class ChooseArrivalPage extends StatefulWidget {
  final Departure departure;
  final int? journeyId;

  const ChooseArrivalPage({
    super.key,
    this.journeyId,
    required this.departure,
  });

  @override
  State<ChooseArrivalPage> createState() => _ChooseArrivalPageState();
}

class _ChooseArrivalPageState extends State<ChooseArrivalPage> {
  List<Departure> arrivalList = [];
  Departure? _selectedDeparture;

  void loadArrivals(String ref) async {
    arrivalList = await ApiHandler.tripDetail(
      ref,
      startStationId: widget.departure.stationId,
    );
    setState(() {});
  }

  @override
  initState() {
    super.initState();
    loadArrivals(widget.departure.ref);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(
          'Arrivals for ${widget.departure.vehicleName}',
        ),
      ),
      body: Center(
        child: Column(
          children: [
            Expanded(
              child: SizedBox(
                height: 400,
                child: ArrivalList(
                  departure: widget.departure,
                  arrivalList: arrivalList,
                  onTapped: _handleArrivalTapped,
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  void _handleArrivalTapped(Departure departure, Departure arrival) async {
    // setState(() {
    //   _selectedDeparture = departure;
    // });
    departure.dbInsert;
    arrival.dbInsert;
    Segment newSegment = await Segment.fromDepartures(departure, arrival);
    Station startStation = await Station.dbGet(arrival.stationId);
    int journeyId;
    if (widget.journeyId == null) {
      Journey journey = await Journey.fromSegment(newSegment);
      journeyId = journey.id as int;
    } else {
      Segment segment = newSegment;
      Journey.dbAppendJourneySegment(
        widget.journeyId as int,
        segment.id as int,
      );
      journeyId = widget.journeyId as int;
    }
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => ChooseDeparturePage(
          startStation: startStation,
          journeyId: journeyId,
          arrival: arrival,
        ),
      ),
    );
  }
}

class ArrivalList extends StatelessWidget {
  final Departure departure;
  final List<Departure> arrivalList;
  final Function onTapped;

  const ArrivalList({
    super.key,
    required this.departure,
    required this.arrivalList,
    required this.onTapped,
  });

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        for (Departure arrival in arrivalList)
          ListTile(
            title: Text(arrival.stationName),
            subtitle: Text(arrival.arrivalTime.toString()),
            onTap: () => onTapped(departure, arrival),
          ),
      ],
    );
  }
}

class JourneyDetailPage extends StatefulWidget {
  final Journey singleJourney;

  const JourneyDetailPage({
    super.key,
    required this.singleJourney,
  });

  @override
  State<JourneyDetailPage> createState() => _JourneyDetailPageState();
}

class _JourneyDetailPageState extends State<JourneyDetailPage> {
  Duration duration = Duration(minutes: 0);

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

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: ListTile(
          title: Text(
            '${widget.singleJourney.startStation} → ${widget.singleJourney.endStation}',
          ),
          subtitle: Text(
            '${widget.singleJourney.duration.toString().split(".")[0]}h',
          ),
        ),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Expanded(
              child: SizedBox(
                height: 400,
                child: SegmentList(journey: widget.singleJourney),
              ),
            ),
            Container(
              margin: const EdgeInsets.only(bottom: 60.0),
              child: ElevatedButton(
                onPressed: () {
                  Navigator.push(
                    context,
                    MaterialPageRoute(
                      builder: (context) => JourneyOverviewPage(),
                    ),
                  );
                },
                child: const Text('View all Journeys'),
              ),
            ),
          ],
        ),
      ),
    );
  }
}

class SegmentList extends StatelessWidget {
  final Journey journey;

  const SegmentList({
    super.key,
    required this.journey,
  });

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        for (Segment seg in journey.segments)
          Card(
            child: Column(
              mainAxisSize: .min,
              children: [
                Container(
                  padding: EdgeInsets.only(left: 10, top: 10),
                  child: Row(
                    children: [
                      Text(
                        seg.vehicle.name,
                        textScaler: TextScaler.linear(1.1),
                      ),
                      Icon(Icons.arrow_right_alt),
                      Text('${seg.start.direction}'),
                    ],
                  ),
                ),
                ListTile(
                  leading: Text(
                    timeOf(seg.start.departureTime),
                    textScaler: TextScaler.linear(1.4),
                  ),
                  title: Text(seg.start.stationName),
                ),
                ListTile(
                  leading: Text(
                    timeOf(seg.end.arrivalTime),
                    textScaler: TextScaler.linear(1.4),
                  ),
                  title: Text(seg.end.stationName),
                ),
              ],
            ),
          ),
      ],
    );
  }
}

class JourneyOverviewPage extends StatefulWidget {
  const JourneyOverviewPage({super.key});
  @override
  State<JourneyOverviewPage> createState() => _JourneyOverviewPageState();
}

class _JourneyOverviewPageState extends State<JourneyOverviewPage> {
  List<Journey> allJourneys = <Journey>[];

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

  // void retry() async {
  //   // retry with setstate
  //   await Future.delayed(Duration(milliseconds: 1300));
  //   setState(() {});
  // }

  Future<List<Journey>> loadJourneys() async {
    // TODO: implement batch query to get a list (all) of journeys
    List<Journey> journeys;
    if (allJourneys.isEmpty) {
      await Future.delayed(Duration(milliseconds: 500));
      journeys = await Journey.dbGetAll();
      allJourneys = journeys;
    } else {
      journeys = allJourneys;
    }
    return journeys;
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Your Journeys"),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            FutureBuilder(
              future: loadJourneys(),
              builder: (context, snapshot) {
                if (snapshot.connectionState == ConnectionState.waiting) {
                  return Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    spacing: 16,
                    children: [
                      const CircularProgressIndicator(),
                      const Text('Loading Journeys...'),
                    ],
                  );
                }
                if (snapshot.hasError) {
                  return Column(
                    children: [
                      Text('couldn\'t load Journeys'),
                      ElevatedButton(
                        onPressed: () {
                          Future.delayed(Duration(milliseconds: 300));
                          setState(() {});
                        },
                        child: const Text('retry'),
                      ),
                    ],
                  );
                }
                if (snapshot.hasData == false) {
                  return Column(
                    children: [
                      Text('No journeys found'),
                      ElevatedButton(
                        onPressed: () {
                          Future.delayed(Duration(milliseconds: 300));
                          setState(() {});
                        },
                        child: const Text('retry'),
                      ),
                    ],
                  );
                }
                return Expanded(
                  child: SizedBox(
                    height: 1,
                    child: JourneyList(
                      journeys: snapshot.data!,
                      onTapped: _handleJourneyTapped,
                    ),
                  ),
                );
              },
            ),
            // ElevatedButton(
            //   onPressed: () {
            //     Navigator.push(
            //       context,
            //       MaterialPageRoute(
            //         builder: (context) => ChooseStationPage(),
            //       ),
            //     );
            //   },
            //   child: const Text('Start a route'),
            // ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        backgroundColor: Theme.of(context).colorScheme.primaryContainer,
        foregroundColor: Theme.of(context).colorScheme.onPrimaryContainer,
        onPressed: () {
          Navigator.push(
            context,
            MaterialPageRoute(builder: (context) => ChooseStationPage()),
          );
        },
        tooltip: 'Start a route',
        child: const Icon(Icons.add),
      ),
    );
  }

  void _handleJourneyTapped(Journey journey) async {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => JourneyDetailPage(singleJourney: journey),
      ),
    );
  }
}

class JourneyList extends StatelessWidget {
  final List<Journey> journeys;
  final Function onTapped;

  const JourneyList({
    super.key,
    required this.journeys,
    required this.onTapped,
  });

  @override
  Widget build(BuildContext context) {
    return ListView(
      children: [
        for (Journey jour in journeys)
          Card(
            margin: EdgeInsets.only(
              left: 3.0,
              top: 3.0,
              bottom: 3.0,
              right: 3.0,
            ),
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.all(
                Radius.circular(0.0),
              ),
            ),
            elevation: 0.3,
            clipBehavior: .hardEdge,
            child: InkWell(
              child: Column(
                mainAxisSize: .min,
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Container(
                    padding: EdgeInsets.only(
                      left: 15.0,
                      top: 7.0,
                      bottom: 7.0,
                      right: 10.0,
                    ),
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(
                          '${jour.startStation}',
                          textScaler: TextScaler.linear(1.2),
                        ),
                        Row(
                          children: [
                            Icon(
                              Icons.arrow_right_alt,
                              size: 25.0,
                            ),
                            Text(
                              '${jour.endStation}',
                              textScaler: TextScaler.linear(1.2),
                            ),
                          ],
                        ),
                      ],
                    ),
                  ),
                ],
              ),
              onTap: () => onTapped(jour),
            ),
          ),
      ],
    );
  }
}