import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';

import 'package:cached_network_image/cached_network_image.dart';
import 'package:characters/characters.dart';
import 'package:future_loading_dialog/future_loading_dialog.dart';
import 'package:matrix/matrix.dart';

import 'package:fluffychat/config/app_config.dart';
import 'package:fluffychat/utils/platform_infos.dart';
import 'package:fluffychat/widgets/avatar.dart';
import 'package:fluffychat/widgets/matrix.dart';

class MessageReactions extends StatelessWidget {
  final Event event;
  final Timeline timeline;

  const MessageReactions(this.event, this.timeline, {Key key})
      : super(key: key);

  @override
  Widget build(BuildContext context) {
    final allReactionEvents =
        event.aggregatedEvents(timeline, RelationshipTypes.reaction);
    final reactionMap = <String, _ReactionEntry>{};
    final client = Matrix.of(context).client;

    for (final e in allReactionEvents) {
      if (e.content['m.relates_to'].containsKey('key')) {
        final key = e.content['m.relates_to']['key'];
        if (!reactionMap.containsKey(key)) {
          reactionMap[key] = _ReactionEntry(
            key: key,
            count: 0,
            reacted: false,
            reactors: [],
          );
        }
        reactionMap[key].count++;
        reactionMap[key].reactors.add(e.sender);
        reactionMap[key].reacted |= e.senderId == e.room.client.userID;
      }
    }
    final reactionList = reactionMap.values.toList();
    reactionList.sort((a, b) => b.count - a.count > 0 ? 1 : -1);
    return Wrap(
        spacing: 4.0,
        runSpacing: 4.0,
        children: reactionList
            .map(
              (r) => _Reaction(
                reactionKey: r.key,
                count: r.count,
                reacted: r.reacted,
                onTap: () {
                  if (r.reacted) {
                    final evt = allReactionEvents.firstWhere(
                        (e) =>
                            e.senderId == e.room.client.userID &&
                            e.content['m.relates_to']['key'] == r.key,
                        orElse: () => null);
                    if (evt != null) {
                      showFutureLoadingDialog(
                        context: context,
                        future: () => evt.redactEvent(),
                      );
                    }
                  } else {
                    showFutureLoadingDialog(
                        context: context,
                        future: () =>
                            event.room.sendReaction(event.eventId, r.key));
                  }
                },
                onLongPress: () async => await _AdaptableReactorsDialog(
                  client: client,
                  reactionEntry: r,
                ).show(context),
              ),
            )
            .toList());
  }
}

class _Reaction extends StatelessWidget {
  final String reactionKey;
  final int count;
  final bool reacted;
  final void Function() onTap;
  final void Function() onLongPress;

  const _Reaction({
    this.reactionKey,
    this.count,
    this.reacted,
    this.onTap,
    this.onLongPress,
  });

  @override
  Widget build(BuildContext context) {
    final borderColor = reacted
        ? Theme.of(context).primaryColor
        : Theme.of(context).dividerColor;
    final textColor = Theme.of(context).brightness == Brightness.dark
        ? Colors.white
        : Colors.black;
    final color = Theme.of(context).scaffoldBackgroundColor;
    final fontSize = DefaultTextStyle.of(context).style.fontSize;
    Widget content;
    if (reactionKey.startsWith('mxc://')) {
      final src = Uri.parse(reactionKey)?.getThumbnail(
        Matrix.of(context).client,
        width: 9999,
        height: fontSize * MediaQuery.of(context).devicePixelRatio,
        method: ThumbnailMethod.scale,
      );
      content = Row(
        mainAxisSize: MainAxisSize.min,
        children: <Widget>[
          CachedNetworkImage(
            imageUrl: src.toString(),
            height: fontSize,
          ),
          const SizedBox(width: 4),
          Text(count.toString(),
              style: TextStyle(
                color: textColor,
                fontSize: DefaultTextStyle.of(context).style.fontSize,
              )),
        ],
      );
    } else {
      var renderKey = Characters(reactionKey);
      if (renderKey.length > 10) {
        renderKey = renderKey.getRange(0, 9) + Characters('…');
      }
      content = Text('$renderKey $count',
          style: TextStyle(
            color: textColor,
            fontSize: DefaultTextStyle.of(context).style.fontSize,
          ));
    }
    return InkWell(
      onTap: () => onTap != null ? onTap() : null,
      onLongPress: () => onLongPress != null ? onLongPress() : null,
      borderRadius: BorderRadius.circular(AppConfig.borderRadius),
      child: Container(
        decoration: BoxDecoration(
          color: color,
          border: Border.all(
            width: 1,
            color: borderColor,
          ),
          borderRadius: BorderRadius.circular(AppConfig.borderRadius),
        ),
        padding: const EdgeInsets.symmetric(horizontal: 5, vertical: 3),
        child: content,
      ),
    );
  }
}

class _ReactionEntry {
  String key;
  int count;
  bool reacted;
  List<User> reactors;

  _ReactionEntry({this.key, this.count, this.reacted, this.reactors});
}

class _AdaptableReactorsDialog extends StatelessWidget {
  final Client client;
  final _ReactionEntry reactionEntry;

  const _AdaptableReactorsDialog({
    Key key,
    this.client,
    this.reactionEntry,
  }) : super(key: key);

  Future<bool> show(BuildContext context) => PlatformInfos.isCupertinoStyle
      ? showCupertinoDialog(
          context: context,
          builder: (context) => this,
          barrierDismissible: true,
          useRootNavigator: false,
        )
      : showDialog(
          context: context,
          builder: (context) => this,
          barrierDismissible: true,
          useRootNavigator: false,
        );

  @override
  Widget build(BuildContext context) {
    final body = SingleChildScrollView(
      child: Wrap(
        spacing: 8.0,
        runSpacing: 4.0,
        alignment: WrapAlignment.center,
        children: <Widget>[
          for (var reactor in reactionEntry.reactors)
            Chip(
              avatar: Avatar(
                reactor.avatarUrl,
                reactor.displayName,
                client: client,
              ),
              label: Text(reactor.displayName),
            ),
        ],
      ),
    );

    final title = Center(child: Text(reactionEntry.key));

    return PlatformInfos.isCupertinoStyle
        ? CupertinoAlertDialog(
            title: title,
            content: body,
          )
        : AlertDialog(
            title: title,
            content: body,
          );
  }
}