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

import 'package:adaptive_dialog/adaptive_dialog.dart';
import 'package:famedlysdk/famedlysdk.dart';
import 'package:fluffychat/components/connection_status_header.dart';
import 'package:fluffychat/components/default_app_bar_search_field.dart';
import 'package:fluffychat/components/default_drawer.dart';
import 'package:future_loading_dialog/future_loading_dialog.dart';
import 'package:fluffychat/app_config.dart';
import 'package:fluffychat/utils/platform_infos.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:flutter_gen/gen_l10n/l10n.dart';
import 'package:receive_sharing_intent/receive_sharing_intent.dart';

import '../components/adaptive_page_layout.dart';
import '../components/list_items/chat_list_item.dart';
import '../components/matrix.dart';
import '../utils/app_route.dart';
import '../utils/matrix_file_extension.dart';
import '../utils/url_launcher.dart';
import 'empty_page.dart';
import 'homeserver_picker.dart';
import 'new_private_chat.dart';

enum SelectMode { normal, share, select }

class ChatListView extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return AdaptivePageLayout(
      primaryPage: FocusPage.FIRST,
      firstScaffold: ChatList(),
      secondScaffold: EmptyPage(),
    );
  }
}

class ChatList extends StatefulWidget {
  final String activeChat;

  const ChatList({this.activeChat, Key key}) : super(key: key);

  @override
  _ChatListState createState() => _ChatListState();
}

class _ChatListState extends State<ChatList> {
  bool get searchMode => searchController.text?.isNotEmpty ?? false;
  final TextEditingController searchController = TextEditingController();
  final _selectedRoomIds = <String>{};

  final ScrollController _scrollController = ScrollController();
  bool _scrolledToTop = true;

  void _toggleSelection(String roomId) =>
      setState(() => _selectedRoomIds.contains(roomId)
          ? _selectedRoomIds.remove(roomId)
          : _selectedRoomIds.add(roomId));

  Future<void> waitForFirstSync(BuildContext context) async {
    var client = Matrix.of(context).client;
    if (client.prevBatch?.isEmpty ?? true) {
      await client.onFirstSync.stream.first;
    }
    return true;
  }

  @override
  void initState() {
    _scrollController.addListener(() async {
      if (_scrollController.position.pixels > 0 && _scrolledToTop) {
        setState(() => _scrolledToTop = false);
      } else if (_scrollController.position.pixels == 0 && !_scrolledToTop) {
        setState(() => _scrolledToTop = true);
      }
    });
    _initReceiveSharingIntent();
    super.initState();
  }

  StreamSubscription _intentDataStreamSubscription;

  StreamSubscription _intentFileStreamSubscription;

  void _processIncomingSharedFiles(List<SharedMediaFile> files) {
    if (files?.isEmpty ?? true) return;
    if (Navigator.of(context).canPop()) {
      Navigator.of(context).popUntil((r) => r.isFirst);
    }
    final file = File(files.first.path);

    Matrix.of(context).shareContent = {
      'msgtype': 'chat.fluffy.shared_file',
      'file': MatrixFile(
        bytes: file.readAsBytesSync(),
        name: file.path,
      ).detectFileType,
    };
  }

  void _processIncomingSharedText(String text) {
    if (text == null) return;
    if (Navigator.of(context).canPop()) {
      Navigator.of(context).popUntil((r) => r.isFirst);
    }
    if (text.toLowerCase().startsWith(AppConfig.inviteLinkPrefix) ||
        (text.toLowerCase().startsWith(AppConfig.schemePrefix) &&
            !RegExp(r'\s').hasMatch(text))) {
      UrlLauncher(context, text).openMatrixToUrl();
      return;
    }
    Matrix.of(context).shareContent = {
      'msgtype': 'm.text',
      'body': text,
    };
  }

  void _initReceiveSharingIntent() {
    if (!PlatformInfos.isMobile) return;

    // For sharing images coming from outside the app while the app is in the memory
    _intentFileStreamSubscription = ReceiveSharingIntent.getMediaStream()
        .listen(_processIncomingSharedFiles, onError: print);

    // For sharing images coming from outside the app while the app is closed
    ReceiveSharingIntent.getInitialMedia().then(_processIncomingSharedFiles);

    // For sharing or opening urls/text coming from outside the app while the app is in the memory
    _intentDataStreamSubscription = ReceiveSharingIntent.getTextStream()
        .listen(_processIncomingSharedText, onError: print);

    // For sharing or opening urls/text coming from outside the app while the app is closed
    ReceiveSharingIntent.getInitialText().then(_processIncomingSharedText);
  }

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

  Future<void> _toggleUnread(BuildContext context) {
    final room = Matrix.of(context).client.getRoomById(_selectedRoomIds.single);
    return showFutureLoadingDialog(
      context: context,
      future: () => room.setUnread(!room.isUnread),
    );
  }

  Future<void> _toggleFavouriteRoom(BuildContext context) {
    final room = Matrix.of(context).client.getRoomById(_selectedRoomIds.single);
    return showFutureLoadingDialog(
      context: context,
      future: () => room.setFavourite(!room.isFavourite),
    );
  }

  Future<void> _toggleMuted(BuildContext context) {
    final room = Matrix.of(context).client.getRoomById(_selectedRoomIds.single);
    return showFutureLoadingDialog(
      context: context,
      future: () => room.setPushRuleState(
          room.pushRuleState == PushRuleState.notify
              ? PushRuleState.mentions_only
              : PushRuleState.notify),
    );
  }

  Future<void> _archiveAction(BuildContext context) async {
    final confirmed = await showOkCancelAlertDialog(
          context: context,
          title: L10n.of(context).areYouSure,
        ) ==
        OkCancelResult.ok;
    if (!confirmed) return;
    await showFutureLoadingDialog(
      context: context,
      future: () => _archiveSelectedRooms(context),
    );
    setState(() => null);
  }

  Future<void> _archiveSelectedRooms(BuildContext context) async {
    final client = Matrix.of(context).client;
    while (_selectedRoomIds.isNotEmpty) {
      final roomId = _selectedRoomIds.first;
      await client.getRoomById(roomId).leave();
      _selectedRoomIds.remove(roomId);
    }
  }

  @override
  Widget build(BuildContext context) {
    return StreamBuilder<LoginState>(
        stream: Matrix.of(context).client.onLoginStateChanged.stream,
        builder: (context, snapshot) {
          if (snapshot.data == LoginState.loggedOut) {
            Timer(Duration(seconds: 1), () {
              Matrix.of(context).clean();
              Navigator.of(context).pushAndRemoveUntil(
                  AppRoute.defaultRoute(context, HomeserverPicker()),
                  (r) => false);
            });
          }
          return StreamBuilder(
              stream: Matrix.of(context).onShareContentChanged.stream,
              builder: (context, snapshot) {
                final selectMode = Matrix.of(context).shareContent == null
                    ? _selectedRoomIds.isEmpty
                        ? SelectMode.normal
                        : SelectMode.select
                    : SelectMode.share;
                if (selectMode == SelectMode.share) {
                  _selectedRoomIds.clear();
                }
                Room selectedRoom;
                if (_selectedRoomIds.length == 1) {
                  selectedRoom = Matrix.of(context)
                      .client
                      .getRoomById(_selectedRoomIds.single);
                }
                return Scaffold(
                  drawer:
                      selectMode != SelectMode.normal ? null : DefaultDrawer(),
                  appBar: AppBar(
                    centerTitle: false,
                    elevation: _scrolledToTop ? 0 : null,
                    leading: selectMode == SelectMode.share
                        ? IconButton(
                            icon: Icon(Icons.close),
                            onPressed: () =>
                                Matrix.of(context).shareContent = null,
                          )
                        : selectMode == SelectMode.select
                            ? IconButton(
                                icon: Icon(Icons.close),
                                onPressed: () =>
                                    setState(_selectedRoomIds.clear),
                              )
                            : null,
                    titleSpacing: 0,
                    actions: selectMode != SelectMode.select
                        ? null
                        : [
                            if (_selectedRoomIds.length == 1)
                              IconButton(
                                tooltip: L10n.of(context).toggleUnread,
                                icon: Icon(selectedRoom.isUnread
                                    ? Icons.mark_chat_read_outlined
                                    : Icons.mark_chat_unread_outlined),
                                onPressed: () => _toggleUnread(context),
                              ),
                            if (_selectedRoomIds.length == 1)
                              IconButton(
                                tooltip: L10n.of(context).toggleFavorite,
                                icon: Icon(Icons.push_pin_outlined),
                                onPressed: () => _toggleFavouriteRoom(context),
                              ),
                            if (_selectedRoomIds.length == 1)
                              IconButton(
                                icon: Icon(selectedRoom.pushRuleState ==
                                        PushRuleState.notify
                                    ? Icons.notifications_off_outlined
                                    : Icons.notifications_outlined),
                                tooltip: L10n.of(context).toggleMuted,
                                onPressed: () => _toggleMuted(context),
                              ),
                            IconButton(
                              icon: Icon(Icons.archive_outlined),
                              tooltip: L10n.of(context).archive,
                              onPressed: () => _archiveAction(context),
                            ),
                          ],
                    title: selectMode == SelectMode.share
                        ? Text(L10n.of(context).share)
                        : selectMode == SelectMode.select
                            ? Text(_selectedRoomIds.length.toString())
                            : DefaultAppBarSearchField(
                                searchController: searchController,
                                hintText: L10n.of(context).searchForAChat,
                                onChanged: (_) => setState(() => null),
                              ),
                  ),
                  floatingActionButton: AdaptivePageLayout.columnMode(context)
                      ? null
                      : FloatingActionButton(
                          child: Icon(Icons.add_outlined),
                          backgroundColor: Theme.of(context).primaryColor,
                          onPressed: () => Navigator.of(context)
                              .pushAndRemoveUntil(
                                  AppRoute.defaultRoute(
                                      context, NewPrivateChatView()),
                                  (r) => r.isFirst),
                        ),
                  body: Column(
                    children: [
                      ConnectionStatusHeader(),
                      Expanded(
                        child: StreamBuilder(
                            stream: Matrix.of(context)
                                .client
                                .onSync
                                .stream
                                .where((s) => s.hasRoomUpdate),
                            builder: (context, snapshot) {
                              return FutureBuilder<void>(
                                future: waitForFirstSync(context),
                                builder: (BuildContext context, snapshot) {
                                  if (snapshot.hasData) {
                                    var rooms = List<Room>.from(
                                        Matrix.of(context).client.rooms);
                                    rooms.removeWhere((Room room) =>
                                        room.lastEvent == null ||
                                        (searchMode &&
                                            !room.displayname
                                                .toLowerCase()
                                                .contains(searchController.text
                                                        .toLowerCase() ??
                                                    '')));
                                    if (rooms.isEmpty && (!searchMode)) {
                                      return Center(
                                        child: Column(
                                          mainAxisSize: MainAxisSize.min,
                                          children: <Widget>[
                                            Icon(
                                              searchMode
                                                  ? Icons.search_outlined
                                                  : Icons.chat_bubble_outline,
                                              size: 80,
                                              color: Colors.grey,
                                            ),
                                            Text(searchMode
                                                ? L10n.of(context).noRoomsFound
                                                : L10n.of(context)
                                                    .startYourFirstChat),
                                          ],
                                        ),
                                      );
                                    }
                                    final totalCount = rooms.length;
                                    return ListView.separated(
                                      controller: _scrollController,
                                      separatorBuilder: (BuildContext context,
                                              int i) =>
                                          i == totalCount
                                              ? ListTile(
                                                  title: Text(
                                                    L10n.of(context)
                                                            .publicRooms +
                                                        ':',
                                                    style: TextStyle(
                                                      fontWeight:
                                                          FontWeight.bold,
                                                      color: Theme.of(context)
                                                          .primaryColor,
                                                    ),
                                                  ),
                                                )
                                              : Container(),
                                      itemCount: totalCount,
                                      itemBuilder:
                                          (BuildContext context, int i) =>
                                              ChatListItem(
                                        rooms[i],
                                        selected: _selectedRoomIds
                                            .contains(rooms[i].id),
                                        onTap: selectMode == SelectMode.select
                                            ? () =>
                                                _toggleSelection(rooms[i].id)
                                            : null,
                                        onLongPress: selectMode !=
                                                SelectMode.share
                                            ? () =>
                                                _toggleSelection(rooms[i].id)
                                            : null,
                                        activeChat:
                                            widget.activeChat == rooms[i].id,
                                      ),
                                    );
                                  } else {
                                    return Center(
                                      child: CircularProgressIndicator(),
                                    );
                                  }
                                },
                              );
                            }),
                      ),
                    ],
                  ),
                );
              });
        });
  }
}