import 'package:Envelope/database/repositories/friends_repository.dart';
import 'package:Envelope/services/friends_service.dart';
import 'package:flutter/material.dart';

import '/components/custom_title_bar.dart';
import '/components/qr_reader.dart';
import '/components/custom_expandable_fab.dart';
import '/database/models/friends.dart';
import '/views/main/friend/list_item.dart';
import '/views/main/friend/add_search.dart';
import '/views/main/friend/request_list_item.dart';

class FriendList extends StatefulWidget {
  final List<Friend> friends;
  final Function callback;

  const FriendList({
    Key? key,
    required this.friends,
    required this.callback,
  }) : super(key: key);

  @override
  State<FriendList> createState() => _FriendListState();
}

class _FriendListState extends State<FriendList> {
  final GlobalKey<RefreshIndicatorState> _refreshIndicatorKey = GlobalKey<RefreshIndicatorState>();
  late ScrollController _scrollController;

  List<Friend> friends = [];
  List<Friend> friendsDuplicate = [];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: const CustomTitleBar(
        title: Text(
          'Friends',
          style: TextStyle(
            fontSize: 32,
            fontWeight: FontWeight.bold
          )
        ),
        showBack: false,
        backgroundColor: Colors.transparent,
      ),
      body: Padding(
        padding: const EdgeInsets.only(top: 16,left: 16,right: 16, bottom: 65),
        child: Stack(
          children: <Widget>[
            Padding(
              padding: const EdgeInsets.only(top: 50),
              child: RefreshIndicator(
                key: _refreshIndicatorKey,
                onRefresh: _refresh,
                child: list(),
              )
            ),
            TextField(
              decoration: const InputDecoration(
                hintText: 'Search...',
                prefixIcon: Icon(
                  Icons.search,
                  size: 20
                ),
              ),
              onChanged: (value) => filterSearchResults(value.toLowerCase())
            ),
          ],
        ),
      ),
      floatingActionButton: Padding(
        padding: const EdgeInsets.only(right: 10, bottom: 60),
        child: ExpandableFab(
          icon: Icon(
            Icons.add,
            size: 30,
            color: Theme.of(context).colorScheme.onPrimary,
          ),
          distance: 90.0,
          children: [
            ActionButton(
              onPressed: () {
                Navigator.of(context).push(
                  MaterialPageRoute(builder: (context) => const QrReader())
                );//.then(onGoBack); // TODO
              },
              icon: const Icon(Icons.qr_code_2, size: 25),
            ),
            ActionButton(
              onPressed: () {
                Navigator.of(context).push(
                  MaterialPageRoute(builder: (context) => const FriendAddSearch())
                );//.then(onGoBack); // TODO
              },
              icon: const Icon(Icons.search, size: 25),
            ),
          ],
         )
      )
    );
  }

  void filterSearchResults(String query) {
    List<Friend> dummyFriendsList = [];
    dummyFriendsList.addAll(friends);

    if (query.isNotEmpty) {
      List<Friend> dummyFriendData = [];

      for (Friend item in dummyFriendsList) {
        if(item.username.toLowerCase().contains(query)) {
          dummyFriendData.add(item);
        }
      }

      setState(() {
        friends.clear();
        friends.addAll(dummyFriendData);
      });

      return;
    }

    setState(() {
      friends.clear();
      friends.addAll(widget.friends);
    });
  }

  @override
  void initState() {
    _scrollController = ScrollController();
    _scrollController.addListener(_scrollListener);
    super.initState();
    friends.addAll(widget.friends);
  }

  Future<void> initFriends() async {
    friends = await FriendsRepository.getFriends();
    setState(() {});
    widget.callback();
  }

  Widget _heading(String heading) {
    return Padding(
      padding: const EdgeInsets.only(top: 5, bottom: 10),
      child: Align(
        alignment: Alignment.centerLeft,
        child: Text(
          heading,
          style: TextStyle(
            fontSize: 16,
            color: Theme.of(context).hintColor,
          ),
        ),
      )
    );
  }

  Widget list() {
    if (friends.isEmpty) {
      return const Center(
        child: Text('No Friends'),
      );
    }

    return ListView.separated(
      controller: _scrollController,
      itemCount: friends.length,
      shrinkWrap: false,
      physics: const AlwaysScrollableScrollPhysics(),
      padding: const EdgeInsets.only(top: 10),
      separatorBuilder: (context, i) {
        if (friends[i].acceptedAt == null) {
          return FriendRequestListItem(
            friend: friends[i],
            callback: initFriends,
          );
        }

        return FriendListItem(
          friend: friends[i],
        );
      },
      itemBuilder: (context, i) {
        if (i == 0 && friends[i].acceptedAt == null) {
          return _heading('Friend Requests');
        }

        if ((i == 0 || friends[i - 1].acceptedAt == null) && friends[i].acceptedAt != null) {
          return _heading('Friends');
        }

        return const SizedBox.shrink();
      },
    );
  }

  Future<void> _refresh() async {
    DateTime? acceptedAt = await FriendsRepository.getLatestAcceptedAt();
    if (acceptedAt == null) {
      return;
    }

    FriendsService.updateFriends(acceptedAt: acceptedAt);
    friends = await FriendsRepository.getFriends();
    setState(() {});
  }

  Future<void> _scrollListener() async {
    if (!(_scrollController.offset >= _scrollController.position.maxScrollExtent)) {
      return;
    }

    int page = 0;

    if (friends.length > 19) {
      page = friends.length ~/ 20;
    }

    await FriendsService.updateFriends(page: page);
    friends = await FriendsRepository.getFriends();
    setState(() {});
  }
}