// Singleton
import 'dart:async';

import 'package:bus_infotainment/audio_cache.dart';
import 'package:bus_infotainment/tfl_datasets.dart';
import 'package:bus_infotainment/utils/audio%20wrapper.dart';
import 'package:bus_infotainment/utils/delegates.dart';
import 'package:flutter/services.dart';
import 'package:http/http.dart' as http;

class LiveInformation {

  static final LiveInformation _singleton = LiveInformation._internal();

  factory LiveInformation() {
    return _singleton;
  }

  LiveInformation._internal();

  Future<void> LoadDatasets() async {

    {
      // Load the bus sequences

      try {

        http.Response response = await http.get(Uri.parse('https://tfl.gov.uk/bus-sequences.csv'));

        busSequences = BusSequences.fromCSV(response.body);

        print("Loaded bus sequences from TFL");

      } catch (e) {

          String csv = await rootBundle.loadString("assets/datasets/bus-sequences.csv");

          busSequences = BusSequences.fromCSV(csv);

          print("Loaded bus sequences from assets");
      }

    }

    refreshTimer();
  }

  Timer refreshTimer() => Timer.periodic(Duration(seconds: 1), (timer) {
    _handleAnnouncementQueue();
  });


  AudioWrapper audioPlayer = AudioWrapper();
  AnnouncementCache announcementCache = AnnouncementCache();
  List<AnnouncementQueueEntry> announcementQueue = [];
  EventDelegate<AnnouncementQueueEntry> announcementDelegate = EventDelegate();
  String CurrentAnnouncement = "*** NO MESSAGE ***";
  void _handleAnnouncementQueue() async {
    print("Handling announcement queue");
    if (audioPlayer.state != AudioWrapper_State.Playing) {
      if (announcementQueue.isNotEmpty) {
        AnnouncementQueueEntry announcement = announcementQueue.first;
        announcementDelegate.trigger(announcement);
        CurrentAnnouncement = announcement.displayText;
        

        
        for (AudioWrapperSource source in announcement.audioSources) {

          Duration? duration = await audioPlayer.play(source);
          if (source == announcement.audioSources.last) {
            announcementQueue.removeAt(0);
          }
          await Future.delayed(duration!);
          await Future.delayed(Duration(milliseconds: 150));
        }
        audioPlayer.stop();
        print("Popped announcement queue");
      }
    }
  }

  void announceRouteVariant(BusRouteVariant routeVariant) async {
    if (routeVariant == null) {
      return;
    }
    String display = "${routeVariant.busRoute.routeNumber} to ${routeVariant.busStops.last.formattedStopName}";

    String audio_route = "R_${routeVariant.busRoute.routeNumber}_001.mp3";
    String audio_destination = routeVariant.busStops.last.getAudioFileName();

    print("Audio file: $audio_route");

    await announcementCache.loadAnnouncements([audio_route, audio_destination]);

    AudioWrapperSource source_route = AudioWrapperByteSource(announcementCache[audio_route]);
    AudioWrapperSource source_destination = AudioWrapperByteSource(announcementCache[audio_destination]);

    queueAnnouncement(AnnouncementQueueEntry(
      displayText: display,
      audioSources: [source_route, AudioWrapperAssetSource("audio/to_destination.wav"), source_destination]
    ));

  }

  late BusSequences busSequences;

  BusRouteVariant? _currentRouteVariant;

  void setRouteVariant(BusRouteVariant routeVariant) {
    _currentRouteVariant = routeVariant;
    announceRouteVariant(routeVariant);
  }

  BusRouteVariant? getRouteVariant() {
    return _currentRouteVariant;
  }

  void queueAnnouncement(AnnouncementQueueEntry announcement) {
    announcementQueue.add(announcement);
  }

  List<ManualAnnouncementEntry> manualAnnouncements = [
    ManualAnnouncementEntry(
      shortName: "Driver Change",
      informationText: "Driver Change",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/driverchange.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "No Standing Upr Deck",
      informationText: "No standing on the upper deck",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/nostanding.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Face Covering",
      informationText: "Please wear a face covering!",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/facecovering.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Seats Upstairs",
      informationText: "Seats are available upstairs",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/seatsupstairs.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Bus Terminates Here",
      informationText: "Bus terminates here. Please take your belongings with you",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/busterminateshere.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Bus On Diversion",
      informationText: "Bus on diversion. Please listen for further announcements",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/busondiversion.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Destination Change",
      informationText: "Destination Changed - please listen for further instructions",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/destinationchange.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Wheelchair Space",
      informationText: "Wheelchair space requested",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/wheelchairspace1.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Move Down The Bus",
      informationText: "Please move down the bus",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/movedownthebus.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Next Stop Closed",
      informationText: "The next bus stop is closed",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/nextstopclosed.wav")],
    ),
    ManualAnnouncementEntry(
      shortName: "CCTV In Operation",
      informationText: "CCTV is in operation on this bus",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/cctvoperation.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Safe Door Opening",
      informationText: "Driver will open the doors when it is safe to do so",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/safedooropening.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Buggy Safety",
      informationText: "For your child's safety, please remain with your buggy",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/buggysafety.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Wheelchair Space 2",
      informationText: "Wheelchair priority space required",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/wheelchairspace2.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Service Regulation",
      informationText: "Regulating service - please listen for further information",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/serviceregulation.mp3")],
    ),
    ManualAnnouncementEntry(
      shortName: "Bus Ready To Depart",
      informationText: "This bus is ready to depart",
      audioSources: [AudioWrapperAssetSource("audio/manual_announcements/readytodepart.mp3")],
    ),
  ];

}

class AnnouncementQueueEntry {
  final String displayText;
  final List<AudioWrapperSource> audioSources;

  AnnouncementQueueEntry({required this.displayText, required this.audioSources});
}

class ManualAnnouncementEntry extends AnnouncementQueueEntry {
  final String shortName;

  ManualAnnouncementEntry({required this.shortName, required String informationText, required List<AudioWrapperSource> audioSources}) : super(displayText: informationText, audioSources: audioSources);
}