import 'dart:async';

import 'package:adaptive_dialog/adaptive_dialog.dart';
import 'package:adaptive_page_layout/adaptive_page_layout.dart';
import 'package:famedlysdk/famedlysdk.dart';
import 'package:fluffychat/components/avatar.dart';
import 'package:fluffychat/components/default_app_bar_search_field.dart';
import 'package:future_loading_dialog/future_loading_dialog.dart';
import 'package:fluffychat/components/matrix.dart';
import 'package:flutter/material.dart';
import 'package:flutter_gen/gen_l10n/l10n.dart';
import '../utils/localized_exception_extension.dart';

class Discover extends StatefulWidget {
  final String alias;

  const Discover({
    Key key,
    this.alias,
  }) : super(key: key);
  @override
  _DiscoverState createState() => _DiscoverState();
}

class _DiscoverState extends State<Discover> {
  Future<PublicRoomsResponse> _publicRoomsResponse;
  String _lastServer;
  Timer _coolDown;
  String _genericSearchTerm;

  void _search(BuildContext context, String query) async {
    _coolDown?.cancel();
    _coolDown = Timer(
      Duration(milliseconds: 500),
      () => setState(() {
        _genericSearchTerm = query;
        _publicRoomsResponse = null;
      }),
    );
  }

  Future<String> _joinRoomAndWait(
    BuildContext context,
    String roomId,
    String alias,
  ) async {
    if (Matrix.of(context).client.getRoomById(roomId) != null) {
      return roomId;
    }
    final newRoomId = await Matrix.of(context)
        .client
        .joinRoomOrAlias(alias?.isNotEmpty ?? false ? alias : roomId);
    await Matrix.of(context)
        .client
        .onRoomUpdate
        .stream
        .firstWhere((r) => r.id == newRoomId);
    return newRoomId;
  }

  void _joinGroupAction(BuildContext context, PublicRoom room) async {
    if (await showOkCancelAlertDialog(
          context: context,
          okLabel: L10n.of(context).joinRoom,
          title: '${room.name} (${room.numJoinedMembers ?? 0})',
          message: room.topic ?? L10n.of(context).noDescription,
        ) ==
        OkCancelResult.cancel) {
      return;
    }
    final success = await showFutureLoadingDialog(
      context: context,
      future: () => _joinRoomAndWait(
        context,
        room.roomId,
        room.canonicalAlias ?? room.aliases.first,
      ),
    );
    if (success.error == null) {
      await AdaptivePageLayout.of(context)
          .pushNamedAndRemoveUntilIsFirst('/rooms/${success.result}');
    }
  }

  String _server;

  void _setServer(BuildContext context) async {
    final newServer = await showTextInputDialog(
        title: L10n.of(context).changeTheHomeserver,
        context: context,
        textFields: [
          DialogTextField(
            prefixText: 'https://',
            hintText: Matrix.of(context).client.homeserver.host,
            initialText: _server,
            keyboardType: TextInputType.url,
          )
        ]);
    if (newServer == null) return;
    setState(() {
      _server = newServer.single;
    });
  }

  @override
  void initState() {
    _genericSearchTerm = widget.alias;
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    final server = _genericSearchTerm?.isValidMatrixId ?? false
        ? _genericSearchTerm.domain
        : _server;
    if (_lastServer != server) {
      _lastServer = server;
      _publicRoomsResponse = null;
    }
    _publicRoomsResponse ??= Matrix.of(context)
        .client
        .searchPublicRooms(
          server: server,
          genericSearchTerm: _genericSearchTerm,
        )
        .catchError((error) {
      if (widget.alias == null) {
        throw error;
      }
      return PublicRoomsResponse.fromJson({
        'chunk': [],
      });
    }).then((PublicRoomsResponse res) {
      if (widget.alias != null &&
          !res.chunk.any((room) =>
              (room.aliases?.contains(widget.alias) ?? false) ||
              room.canonicalAlias == widget.alias)) {
        // we have to tack on the original alias
        res.chunk.add(PublicRoom.fromJson(<String, dynamic>{
          'aliases': [widget.alias],
          'name': widget.alias,
        }));
      }
      return res;
    });
    return Scaffold(
      appBar: AppBar(
        title: Text(L10n.of(context).discoverGroups),
        actions: [
          FlatButton(
            child: Text(
              server ?? Matrix.of(context).client.userID.domain,
              style: TextStyle(color: Theme.of(context).primaryColor),
            ),
            onPressed: () => _setServer(context),
          ),
        ],
      ),
      body: ListView(
        children: [
          Padding(
            padding: EdgeInsets.all(12),
            child: DefaultAppBarSearchField(
              hintText: L10n.of(context).search,
              prefixIcon: Icon(Icons.search_outlined),
              onChanged: (t) => _search(context, t),
              padding: EdgeInsets.zero,
            ),
          ),
          FutureBuilder<PublicRoomsResponse>(
              future: _publicRoomsResponse,
              builder: (BuildContext context,
                  AsyncSnapshot<PublicRoomsResponse> snapshot) {
                if (snapshot.hasError) {
                  return Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      SizedBox(height: 32),
                      Icon(
                        Icons.error_outlined,
                        size: 80,
                        color: Colors.grey,
                      ),
                      Center(
                        child: Text(
                          snapshot.error.toLocalizedString(context),
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            color: Colors.grey,
                            fontSize: 16,
                          ),
                        ),
                      ),
                    ],
                  );
                }
                if (snapshot.connectionState != ConnectionState.done) {
                  return Center(child: CircularProgressIndicator());
                }
                final publicRoomsResponse = snapshot.data;
                if (publicRoomsResponse.chunk.isEmpty) {
                  return Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      SizedBox(height: 32),
                      Icon(
                        Icons.search_outlined,
                        size: 80,
                        color: Colors.grey,
                      ),
                      Center(
                        child: Text(
                          L10n.of(context).noPublicRoomsFound,
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            color: Colors.grey,
                            fontSize: 16,
                          ),
                        ),
                      ),
                    ],
                  );
                }
                return GridView.builder(
                  shrinkWrap: true,
                  padding: EdgeInsets.all(12),
                  physics: NeverScrollableScrollPhysics(),
                  gridDelegate: SliverGridDelegateWithFixedCrossAxisCount(
                    crossAxisCount: 2,
                    childAspectRatio: 1,
                    crossAxisSpacing: 16,
                    mainAxisSpacing: 16,
                  ),
                  itemCount: publicRoomsResponse.chunk.length,
                  itemBuilder: (BuildContext context, int i) => Material(
                    elevation: 2,
                    borderRadius: BorderRadius.circular(16),
                    child: InkWell(
                      onTap: () => _joinGroupAction(
                        context,
                        publicRoomsResponse.chunk[i],
                      ),
                      borderRadius: BorderRadius.circular(16),
                      child: Padding(
                        padding: const EdgeInsets.all(8.0),
                        child: Column(
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            Avatar(
                                Uri.parse(
                                    publicRoomsResponse.chunk[i].avatarUrl ??
                                        ''),
                                publicRoomsResponse.chunk[i].name),
                            Text(
                              publicRoomsResponse.chunk[i].name,
                              style: TextStyle(
                                fontSize: 16,
                                fontWeight: FontWeight.bold,
                              ),
                              maxLines: 1,
                              textAlign: TextAlign.center,
                            ),
                            Text(
                              L10n.of(context).countParticipants(
                                  publicRoomsResponse
                                          .chunk[i].numJoinedMembers ??
                                      0),
                              style: TextStyle(fontSize: 10.5),
                              maxLines: 1,
                              textAlign: TextAlign.center,
                            ),
                            Text(
                              publicRoomsResponse.chunk[i].topic ??
                                  L10n.of(context).noDescription,
                              maxLines: 4,
                              textAlign: TextAlign.center,
                            ),
                          ],
                        ),
                      ),
                    ),
                  ),
                );
              }),
        ],
      ),
    );
  }
}