import 'dart:async';
import 'dart:ui';

import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:solian/controllers/chat_events_controller.dart';
import 'package:solian/exts.dart';
import 'package:solian/models/call.dart';
import 'package:solian/models/channel.dart';
import 'package:solian/models/event.dart';
import 'package:solian/models/packet.dart';
import 'package:solian/providers/auth.dart';
import 'package:solian/providers/call.dart';
import 'package:solian/providers/content/channel.dart';
import 'package:solian/providers/websocket.dart';
import 'package:solian/router.dart';
import 'package:solian/screens/channel/call/call.dart';
import 'package:solian/screens/channel/channel_detail.dart';
import 'package:solian/theme.dart';
import 'package:solian/widgets/app_bar_leading.dart';
import 'package:solian/widgets/app_bar_title.dart';
import 'package:solian/widgets/channel/channel_call_indicator.dart';
import 'package:solian/widgets/chat/call/chat_call_action.dart';
import 'package:solian/widgets/chat/chat_event_list.dart';
import 'package:solian/widgets/chat/chat_message_input.dart';
import 'package:solian/widgets/chat/chat_typing_indicator.dart';
import 'package:solian/widgets/current_state_action.dart';

class ChannelChatScreen extends StatefulWidget {
  final String alias;
  final String realm;

  const ChannelChatScreen({
    super.key,
    required this.alias,
    this.realm = 'global',
  });

  @override
  State<ChannelChatScreen> createState() => _ChannelChatScreenState();
}

class _ChannelChatScreenState extends State<ChannelChatScreen>
    with WidgetsBindingObserver, TickerProviderStateMixin {
  DateTime? _isOutOfSyncSince;

  bool _isBusy = false;
  int? _accountId;

  String? _newAlias;

  Channel? _channel;
  Call? _ongoingCall;
  ChannelMember? _channelProfile;
  StreamSubscription<NetworkPackage>? _subscription;

  late final ChatEventController _chatController;

  _getChannel({String? alias}) async {
    final ChannelProvider provider = Get.find();

    setState(() => _isBusy = true);

    if (alias != null) _newAlias = alias;

    try {
      final resp = await provider.getChannel(
        _newAlias ?? widget.alias,
        realm: widget.realm,
      );
      final respProfile = await provider.getMyChannelProfile(
        _newAlias ?? widget.alias,
        realm: widget.realm,
      );
      setState(() {
        _channel = Channel.fromJson(resp.body);
        _channelProfile = ChannelMember.fromJson(respProfile.body);
      });
    } catch (e) {
      context.showErrorDialog(e);
    }

    setState(() => _isBusy = false);
  }

  _getOngoingCall() async {
    final ChannelProvider provider = Get.find();

    setState(() => _isBusy = true);

    try {
      final resp = await provider.getChannelOngoingCall(
        _newAlias ?? widget.alias,
        realm: widget.realm,
      );
      if (resp != null) {
        setState(() => _ongoingCall = Call.fromJson(resp.body));
      }
    } catch (e) {
      context.showErrorDialog(e);
    }

    setState(() => _isBusy = false);
  }

  final List<ChannelMember> _typingUsers = List.empty(growable: true);
  final Map<int, Timer> _typingInactiveTimer = {};

  void _listenMessages() {
    final WebSocketProvider ws = Get.find();
    _subscription = ws.stream.stream.listen((event) {
      switch (event.method) {
        case 'events.new':
          final payload = Event.fromJson(event.payload!);
          final typingIdx =
              _typingUsers.indexWhere((x) => x.id == payload.senderId);
          if (typingIdx != -1) _typingUsers.removeAt(typingIdx);
          _chatController.receiveEvent(payload);
          break;
        case 'calls.new':
          final payload = Call.fromJson(event.payload!);
          if (payload.channel.id == _channel!.id) {
            setState(() => _ongoingCall = payload);
          }
          break;
        case 'calls.end':
          final payload = Call.fromJson(event.payload!);
          if (payload.channel.id == _channel!.id) {
            setState(() => _ongoingCall = null);
          }
          break;
        case 'status.typing':
          if (event.payload?['channel_id'] != _channel!.id) break;
          final member = ChannelMember.fromJson(event.payload!['member']);
          if (member.id == _channelProfile!.id) break;
          if (!_typingUsers.any((x) => x.id == member.id)) {
            setState(() {
              _typingUsers.add(member);
            });
          }
          _typingInactiveTimer[member.id]?.cancel();
          _typingInactiveTimer[member.id] = Timer(
            const Duration(seconds: 3),
            () {
              setState(() {
                _typingUsers.removeWhere((x) => x.id == member.id);
                _typingInactiveTimer.remove(member.id);
              });
            },
          );
      }
    });
  }

  void _keepUpdateWithServer() {
    _getOngoingCall();
    _chatController.getInitialEvents(_channel!, widget.realm);
    setState(() => _isOutOfSyncSince = null);
  }

  Event? _messageToReplying;
  Event? _messageToEditing;

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    switch (state) {
      case AppLifecycleState.resumed:
        if (_isOutOfSyncSince == null) break;
        if (DateTime.now().difference(_isOutOfSyncSince!).inSeconds < 30) break;
        _keepUpdateWithServer();
        break;
      case AppLifecycleState.paused:
        if (mounted) {
          setState(() => _isOutOfSyncSince = DateTime.now());
        }
        break;
      default:
        break;
    }
  }

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);

    _accountId = Get.find<AuthProvider>().userProfile.value!['id'];

    _chatController = ChatEventController();
    _chatController.initialize();

    _getOngoingCall();
    _getChannel().then((_) {
      _chatController.getInitialEvents(_channel!, widget.realm);
      _listenMessages();
    });
  }

  @override
  Widget build(BuildContext context) {
    String title = _channel?.name ?? 'loading'.tr;
    String? placeholder;

    final otherside =
        _channel?.members!.where((e) => e.account.id != _accountId).firstOrNull;

    if (_channel?.type == 1 && otherside != null) {
      title = otherside.account.nick;
      placeholder = 'messageInputPlaceholder'.trParams(
        {'channel': '@${otherside.account.name}'},
      );
    }

    return Scaffold(
      appBar: AppBar(
        leading: AppBarLeadingButton.adaptive(context),
        title: AppBarTitle(title),
        centerTitle: false,
        titleSpacing: AppTheme.titleSpacing(context),
        toolbarHeight: AppTheme.toolbarHeight(context),
        actions: [
          const BackgroundStateWidget(),
          Builder(builder: (context) {
            if (_isBusy || _channel == null) return const SizedBox.shrink();

            return ChatCallButton(
              realm: _channel!.realm,
              channel: _channel!,
              ongoingCall: _ongoingCall,
            );
          }),
          IconButton(
            icon: const Icon(Icons.more_vert),
            onPressed: () {
              if (_channel == null) return;

              AppRouter.instance
                  .pushNamed(
                'channelDetail',
                pathParameters: {'alias': widget.alias},
                queryParameters: {'realm': widget.realm},
                extra: ChannelDetailArguments(
                  profile: _channelProfile!,
                  channel: _channel!,
                ),
              )
                  .then((value) {
                if (value == false) AppRouter.instance.pop();
                if (value != null) {
                  final resp = Channel.fromJson(value as Map<String, dynamic>);
                  _getChannel(alias: resp.alias);
                }
              });
            },
          ),
          SizedBox(
            width: AppTheme.isLargeScreen(context) ? 8 : 16,
          ),
        ],
      ),
      body: Builder(builder: (context) {
        if (_isBusy || _channel == null) {
          return const Center(
            child: CircularProgressIndicator(),
          );
        }

        return Row(
          children: [
            Expanded(
              child: Column(
                children: [
                  if (_ongoingCall != null)
                    ChannelCallIndicator(
                      channel: _channel!,
                      ongoingCall: _ongoingCall!,
                      onJoin: () {
                        if (!AppTheme.isLargeScreen(context)) {
                          final ChatCallProvider call = Get.find();
                          call.gotoScreen(context);
                        }
                      },
                    ),
                  Expanded(
                    child: ChatEventList(
                      scope: widget.realm,
                      channel: _channel!,
                      chatController: _chatController,
                      onEdit: (item) {
                        setState(() => _messageToEditing = item);
                      },
                      onReply: (item) {
                        setState(() => _messageToReplying = item);
                      },
                    ),
                  ),
                  ClipRect(
                    child: BackdropFilter(
                      filter: ImageFilter.blur(sigmaX: 50, sigmaY: 50),
                      child: SafeArea(
                        child: Column(
                          children: [
                            ChatTypingIndicator(users: _typingUsers),
                            ChatMessageInput(
                              edit: _messageToEditing,
                              reply: _messageToReplying,
                              realm: widget.realm,
                              placeholder: placeholder,
                              channel: _channel!,
                              onSent: (Event item) {
                                setState(() {
                                  _chatController.addPendingEvent(item);
                                });
                              },
                              onReset: () {
                                setState(() {
                                  _messageToReplying = null;
                                  _messageToEditing = null;
                                });
                              },
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                ],
              ),
            ),
            Obx(() {
              final ChatCallProvider call = Get.find();
              if (call.isMounted.value && AppTheme.isLargeScreen(context)) {
                return const Expanded(
                  child: Row(children: [
                    VerticalDivider(width: 0.3, thickness: 0.3),
                    Expanded(
                      child: CallScreen(
                        hideAppBar: true,
                        isExpandable: true,
                      ),
                    ),
                  ]),
                );
              }
              return const SizedBox.shrink();
            }),
          ],
        );
      }),
    );
  }

  @override
  void dispose() {
    for (var timer in _typingInactiveTimer.values) {
      timer.cancel();
    }
    _subscription?.cancel();
    WidgetsBinding.instance.removeObserver(this);
    super.dispose();
  }
}