import 'package:flutter/material.dart';

import 'package:async/async.dart';
import 'package:flutter_linkify/flutter_linkify.dart';
import 'package:matrix/matrix.dart' hide Result;

import 'package:fluffychat/config/app_config.dart';
import 'package:fluffychat/config/setting_keys.dart';
import 'package:fluffychat/l10n/l10n.dart';
import 'package:fluffychat/utils/url_launcher.dart';
import 'package:fluffychat/widgets/avatar.dart';
import 'package:fluffychat/widgets/future_loading_dialog.dart';

class PollWidget extends StatelessWidget {
  final Event event;
  final Timeline timeline;
  final Color textColor;
  final Color linkColor;
  const PollWidget({
    required this.event,
    required this.timeline,
    required this.textColor,
    required this.linkColor,
    super.key,
  });

  void _endPoll(BuildContext context) => showFutureLoadingDialog(
        context: context,
        future: () => event.endPoll(),
      );

  void _toggleVote(
    BuildContext context,
    String answerId,
    int maxSelection,
  ) async {
    final userId = event.room.client.userID!;
    final answerIds = event.getPollResponses(timeline)[userId] ?? {};
    if (!answerIds.remove(answerId)) {
      answerIds.add(answerId);
      if (answerIds.length > maxSelection) {
        answerIds.clear();
        answerIds.add(answerId);
      }
    }

    showFutureLoadingDialog(
      context: context,
      future: () => event.answerPoll(answerIds.toList()),
    );
  }

  @override
  Widget build(BuildContext context) {
    final eventContentResult = Result(() => event.parsedPollEventContent);
    final eventContent = eventContentResult.asValue?.value;
    if (eventContent == null) {
      Logs().w('Invalid poll event', eventContentResult.error);
      return const Text('Unable to parse poll event...');
    }
    final responses = event.getPollResponses(timeline);
    final pollHasBeenEnded = event.getPollHasBeenEnded(timeline);
    final canVote = event.room.canSendEvent(PollEventContent.responseType) &&
        !pollHasBeenEnded;
    final maxPolls = responses.length;
    final answersVisible =
        eventContent.pollStartContent.kind == PollKind.disclosed ||
            pollHasBeenEnded;

    return Padding(
      padding: const EdgeInsets.symmetric(
        vertical: 8,
      ),
      child: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Padding(
            padding: const EdgeInsets.symmetric(horizontal: 16),
            child: Linkify(
              text: eventContent.pollStartContent.question.mText,
              textScaleFactor: MediaQuery.textScalerOf(context).scale(1),
              style: TextStyle(
                color: textColor,
                fontSize: AppSettings.fontSizeFactor.value *
                    AppConfig.messageFontSize,
              ),
              options: const LinkifyOptions(humanize: false),
              linkStyle: TextStyle(
                color: linkColor,
                fontSize: AppSettings.fontSizeFactor.value *
                    AppConfig.messageFontSize,
                decoration: TextDecoration.underline,
                decorationColor: linkColor,
              ),
              onOpen: (url) => UrlLauncher(context, url.url).launchUrl(),
            ),
          ),
          Divider(color: linkColor.withAlpha(64)),
          ...eventContent.pollStartContent.answers.map(
            (answer) {
              final votedUserIds = responses.entries
                  .where((entry) => entry.value.contains(answer.id))
                  .map((entry) => entry.key)
                  .toSet();
              return Material(
                color: Colors.transparent,
                clipBehavior: Clip.hardEdge,
                child: CheckboxListTile.adaptive(
                  value: responses[event.room.client.userID!]
                          ?.contains(answer.id) ??
                      false,
                  contentPadding: const EdgeInsets.symmetric(horizontal: 16),
                  checkboxScaleFactor: 1.5,
                  checkboxShape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(32),
                  ),
                  onChanged: !canVote
                      ? null
                      : (_) => _toggleVote(
                            context,
                            answer.id,
                            eventContent.pollStartContent.maxSelections,
                          ),
                  title: Text(
                    answer.mText,
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                    style: TextStyle(
                      color: textColor,
                      fontSize: AppConfig.messageFontSize *
                          AppSettings.fontSizeFactor.value,
                    ),
                  ),
                  subtitle: answersVisible
                      ? Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          mainAxisSize: MainAxisSize.min,
                          children: [
                            SingleChildScrollView(
                              scrollDirection: Axis.horizontal,
                              child: Row(
                                children: [
                                  Text(
                                    L10n.of(context)
                                        .countVotes(votedUserIds.length),
                                    maxLines: 1,
                                    overflow: TextOverflow.ellipsis,
                                    style: TextStyle(
                                      color: linkColor,
                                      fontSize:
                                          12 * AppSettings.fontSizeFactor.value,
                                    ),
                                  ),
                                  const SizedBox(width: 2),
                                  ...votedUserIds.map((userId) {
                                    final user = event.room
                                        .getState(EventTypes.RoomMember, userId)
                                        ?.asUser(event.room);
                                    return Padding(
                                      padding: const EdgeInsets.symmetric(
                                        horizontal: 2.0,
                                      ),
                                      child: Avatar(
                                        mxContent: user?.avatarUrl,
                                        name: user?.calcDisplayname() ??
                                            userId.localpart,
                                        size: 12 *
                                            AppSettings.fontSizeFactor.value,
                                      ),
                                    );
                                  }),
                                  const SizedBox(width: 2),
                                ],
                              ),
                            ),
                            LinearProgressIndicator(
                              color: linkColor,
                              backgroundColor: linkColor.withAlpha(128),
                              borderRadius:
                                  BorderRadius.circular(AppConfig.borderRadius),
                              value: maxPolls == 0
                                  ? 0
                                  : votedUserIds.length / maxPolls,
                            ),
                          ],
                        )
                      : null,
                ),
              );
            },
          ),
          if (!pollHasBeenEnded && event.senderId == event.room.client.userID)
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: 16),
              child: OutlinedButton(
                onPressed: () => _endPoll(context),
                style: OutlinedButton.styleFrom(
                  foregroundColor: linkColor,
                  side: BorderSide(color: linkColor.withAlpha(64)),
                ),
                child: Text(L10n.of(context).endPoll),
              ),
            )
          else if (!answersVisible)
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: 16),
              child: Text(
                L10n.of(context).answersWillBeVisibleWhenPollHasEnded,
                style: TextStyle(
                  color: linkColor,
                  fontSize: 12 * AppSettings.fontSizeFactor.value,
                  fontStyle: FontStyle.italic,
                ),
              ),
            )
          else if (pollHasBeenEnded)
            Padding(
              padding: const EdgeInsets.symmetric(horizontal: 16),
              child: Text(
                L10n.of(context).pollHasBeenEnded,
                style: TextStyle(
                  color: linkColor,
                  fontSize: 12 * AppSettings.fontSizeFactor.value,
                  fontStyle: FontStyle.italic,
                ),
              ),
            ),
        ],
      ),
    );
  }
}