import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';
import 'package:flutter_hooks/flutter_hooks.dart';
import 'package:intl/intl.dart';
import 'package:lemmy_api_client/lemmy_api_client.dart';
import 'package:timeago/timeago.dart' as timeago;

import '../hooks/stores.dart';
import '../util/extensions/api.dart';
import '../util/goto.dart';
import '../util/intl.dart';
import '../util/text_color.dart';
import 'badge.dart';
import 'fullscreenable_image.dart';
import 'markdown_text.dart';
import 'sortable_infinite_list.dart';

/// Shared widget of UserPage and ProfileTab
class UserProfile extends HookWidget {
  final Future<UserDetails> _userDetails;
  final String instanceUrl;

  UserProfile({@required int userId, @required this.instanceUrl})
      : _userDetails = LemmyApi(instanceUrl).v1.getUserDetails(
            userId: userId, savedOnly: false, sort: SortType.active);

  UserProfile.fromUserDetails(UserDetails userDetails)
      : _userDetails = Future.value(userDetails),
        instanceUrl = userDetails.user.instanceUrl;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final userDetailsSnap = useFuture(_userDetails, preserveState: false);

    if (!userDetailsSnap.hasData) {
      return const Center(child: CircularProgressIndicator());
    } else if (userDetailsSnap.hasError) {
      return Center(
        child: Row(mainAxisAlignment: MainAxisAlignment.center, children: [
          Icon(Icons.error),
          Padding(
            padding: const EdgeInsets.all(8),
            child: Text('ERROR: ${userDetailsSnap.error}'),
          )
        ]),
      );
    }

    final userView = userDetailsSnap.data.user;

    return DefaultTabController(
      length: 3,
      child: NestedScrollView(
        headerSliverBuilder: (_, __) => [
          SliverAppBar(
            pinned: true,
            expandedHeight: 265,
            toolbarHeight: 0,
            forceElevated: true,
            elevation: 0,
            backgroundColor: theme.cardColor,
            brightness: theme.brightness,
            iconTheme: theme.iconTheme,
            flexibleSpace:
                FlexibleSpaceBar(background: _UserOverview(userView)),
            bottom: TabBar(
              labelColor: theme.textTheme.bodyText1.color,
              tabs: [
                Tab(text: 'Posts'),
                Tab(text: 'Comments'),
                Tab(text: 'About'),
              ],
            ),
          ),
        ],
        body: TabBarView(children: [
          // TODO: first batch is already fetched on render
          // TODO: comment and post come from the same endpoint, could be shared
          InfinitePostList(
            fetcher: (page, batchSize, sort) => LemmyApi(instanceUrl)
                .v1
                .getUserDetails(
                  userId: userView.id,
                  savedOnly: false,
                  sort: SortType.active,
                  page: page,
                  limit: batchSize,
                )
                .then((val) => val.posts),
          ),
          InfiniteCommentList(
            fetcher: (page, batchSize, sort) => LemmyApi(instanceUrl)
                .v1
                .getUserDetails(
                  userId: userView.id,
                  savedOnly: false,
                  sort: SortType.active,
                  page: page,
                  limit: batchSize,
                )
                .then((val) => val.comments),
          ),
          _AboutTab(userDetailsSnap.data),
        ]),
      ),
    );
  }
}

/// Content in the sliver flexible space
/// Renders general info about the given user.
/// Such as his nickname, no. of posts, no. of posts,
/// banner, avatar etc.
class _UserOverview extends HookWidget {
  final UserView userView;

  const _UserOverview(this.userView);

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colorOnTopOfAccentColor =
        textColorBasedOnBackground(theme.accentColor);

    return Stack(
      children: [
        if (userView.banner != null)
          // TODO: for some reason doesnt react to presses
          FullscreenableImage(
            url: userView.banner,
            child: CachedNetworkImage(
              imageUrl: userView.banner,
              errorWidget: (_, __, ___) => SizedBox.shrink(),
            ),
          )
        else
          Container(
            width: double.infinity,
            height: 200,
            color: theme.accentColor,
          ),
        Container(
          height: 200,
          decoration: BoxDecoration(
            gradient: LinearGradient(
              begin: FractionalOffset.topCenter,
              end: FractionalOffset.bottomCenter,
              colors: [
                Colors.black26,
                Colors.transparent,
              ],
            ),
          ),
        ),
        SafeArea(
          child: Padding(
            padding: const EdgeInsets.only(top: 60),
            child: SizedBox(
              width: double.infinity,
              height: double.infinity,
              child: Container(
                decoration: BoxDecoration(
                  borderRadius: BorderRadius.only(
                    topRight: Radius.circular(40),
                    topLeft: Radius.circular(40),
                  ),
                  color: theme.scaffoldBackgroundColor,
                ),
              ),
            ),
          ),
        ),
        SafeArea(
          child: Column(
            children: [
              if (userView.avatar != null)
                SizedBox(
                  width: 80,
                  height: 80,
                  child: Container(
                    // clipBehavior: Clip.antiAlias,
                    decoration: BoxDecoration(
                      boxShadow: [
                        BoxShadow(blurRadius: 6, color: Colors.black54)
                      ],
                      borderRadius: BorderRadius.all(Radius.circular(15)),
                      border: Border.all(color: Colors.white, width: 3),
                    ),
                    child: ClipRRect(
                      borderRadius: BorderRadius.all(Radius.circular(12)),
                      child: FullscreenableImage(
                        url: userView.avatar,
                        child: CachedNetworkImage(
                          imageUrl: userView.avatar,
                          errorWidget: (_, __, ___) => SizedBox.shrink(),
                        ),
                      ),
                    ),
                  ),
                ),
              Padding(
                padding: userView.avatar != null
                    ? const EdgeInsets.only(top: 8.0)
                    : const EdgeInsets.only(top: 70),
                child: Padding(
                  padding:
                      EdgeInsets.only(top: userView.avatar == null ? 10 : 0),
                  child: Text(
                    userView.preferredUsername ?? userView.name,
                    style: theme.textTheme.headline6,
                  ),
                ),
              ),
              Padding(
                padding: const EdgeInsets.only(top: 4.0),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Text(
                      '@${userView.name}@',
                      style: theme.textTheme.caption,
                    ),
                    InkWell(
                      onTap: () => goToInstance(context, userView.instanceUrl),
                      child: Text(
                        '${userView.instanceUrl}',
                        style: theme.textTheme.caption,
                      ),
                    )
                  ],
                ),
              ),
              Padding(
                padding: const EdgeInsets.only(top: 15),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Badge(
                      child: Row(
                        children: [
                          Icon(
                            Icons.comment, // TODO: should be article icon
                            size: 15,
                            color: colorOnTopOfAccentColor,
                          ),
                          Padding(
                            padding: const EdgeInsets.only(left: 4.0),
                            child: Text(
                              '${compactNumber(userView.numberOfPosts)}'
                              ' Post${pluralS(userView.numberOfPosts)}',
                              style: TextStyle(color: colorOnTopOfAccentColor),
                            ),
                          ),
                        ],
                      ),
                    ),
                    Padding(
                      padding: const EdgeInsets.only(left: 16.0),
                      child: Badge(
                        child: Row(
                          children: [
                            Icon(
                              Icons.comment,
                              size: 15,
                              color: colorOnTopOfAccentColor,
                            ),
                            Padding(
                              padding: const EdgeInsets.only(left: 4.0),
                              child: Text(
                                '${compactNumber(userView.numberOfComments)}'
                                ' Comment${pluralS(userView.numberOfComments)}',
                                style:
                                    TextStyle(color: colorOnTopOfAccentColor),
                              ),
                            ),
                          ],
                        ),
                      ),
                    ),
                  ],
                ),
              ),
              Padding(
                padding: const EdgeInsets.only(top: 15),
                child: Text(
                  'Joined ${timeago.format(userView.published)}',
                  style: theme.textTheme.bodyText1,
                ),
              ),
              Padding(
                padding: const EdgeInsets.only(bottom: 8),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    Icon(
                      Icons.cake,
                      size: 13,
                    ),
                    Padding(
                      padding: const EdgeInsets.only(left: 4.0),
                      child: Text(
                        DateFormat('MMM dd, yyyy').format(userView.published),
                        style: theme.textTheme.bodyText1,
                      ),
                    ),
                  ],
                ),
              ),
              // Expanded(child: tabs())
            ],
          ),
        ),
      ],
    );
  }
}

class _AboutTab extends HookWidget {
  final UserDetails userDetails;

  const _AboutTab(this.userDetails);

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final instanceUrl = userDetails.user.instanceUrl;

    final accStore = useAccountsStore();

    final isOwnedAccount = accStore.loggedInInstances.contains(instanceUrl) &&
        accStore.tokens[instanceUrl].containsKey(userDetails.user.name);

    const wallPadding = EdgeInsets.symmetric(horizontal: 15);

    final divider = Padding(
      padding: EdgeInsets.symmetric(
          horizontal: wallPadding.horizontal / 2, vertical: 10),
      child: Divider(),
    );

    communityTile(String name, String icon, int id) => ListTile(
          dense: true,
          onTap: () => goToCommunity.byId(context, instanceUrl, id),
          title: Text('!$name'),
          leading: icon != null
              ? CachedNetworkImage(
                  height: 40,
                  width: 40,
                  imageUrl: icon,
                  errorWidget: (_, __, ___) => SizedBox(width: 40, height: 40),
                  imageBuilder: (context, imageProvider) => Container(
                        decoration: BoxDecoration(
                          shape: BoxShape.circle,
                          image: DecorationImage(
                            fit: BoxFit.cover,
                            image: imageProvider,
                          ),
                        ),
                      ))
              : SizedBox(width: 40),
        );

    return ListView(
      padding: EdgeInsets.symmetric(vertical: 20),
      children: [
        if (isOwnedAccount)
          ListTile(
            title: Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Icon(Icons.edit),
                SizedBox(width: 10),
                Text('edit profile'),
              ],
            ),
            onTap: () {}, // TODO: go to account editing
          ),
        if (userDetails.user.bio != null) ...[
          Padding(
              padding: wallPadding,
              child:
                  MarkdownText(userDetails.user.bio, instanceUrl: instanceUrl)),
          divider,
        ],
        if (userDetails.moderates.isNotEmpty) ...[
          ListTile(
            title: Center(
              child: Text(
                'Moderates:',
                style: theme.textTheme.headline6.copyWith(fontSize: 18),
              ),
            ),
          ),
          for (final comm
              in userDetails.moderates
                ..sort((a, b) => a.communityName.compareTo(b.communityName)))
            communityTile(
                comm.communityName, comm.communityIcon, comm.communityId),
          divider
        ],
        ListTile(
          title: Center(
            child: Text(
              'Subscribed:',
              style: theme.textTheme.headline6.copyWith(fontSize: 18),
            ),
          ),
        ),
        if (userDetails.follows.isNotEmpty)
          for (final comm
              in userDetails.follows
                ..sort((a, b) => a.communityName.compareTo(b.communityName)))
            communityTile(
                comm.communityName, comm.communityIcon, comm.communityId)
        else
          Padding(
            padding: const EdgeInsets.only(top: 8),
            child: Center(
              child: Text(
                'this user does not subscribe to any community',
                style: TextStyle(fontStyle: FontStyle.italic),
              ),
            ),
          )
      ],
    );
  }
}