import 'dart:collection';

import 'package:fluent_ui/fluent_ui.dart';
import 'package:flutter/gestures.dart';
import 'package:pixes/components/animated_image.dart';
import 'package:pixes/components/grid.dart';
import 'package:pixes/components/loading.dart';
import 'package:pixes/components/md.dart';
import 'package:pixes/components/novel.dart';
import 'package:pixes/components/title_bar.dart';
import 'package:pixes/foundation/app.dart';
import 'package:pixes/foundation/image_provider.dart';
import 'package:pixes/network/network.dart';
import 'package:pixes/pages/comments_page.dart';
import 'package:pixes/pages/novel_reading_page.dart';
import 'package:pixes/pages/search_page.dart';
import 'package:pixes/pages/user_info_page.dart';
import 'package:pixes/utils/app_links.dart';
import 'package:pixes/utils/translation.dart';
import 'package:url_launcher/url_launcher_string.dart';

const kFluentButtonPadding = 28.0;

class NovelPage extends StatefulWidget {
  const NovelPage(this.novel, {super.key});

  final Novel novel;

  @override
  State<NovelPage> createState() => _NovelPageState();
}

class _NovelPageState extends State<NovelPage> {
  final scrollController = ScrollController();

  @override
  Widget build(BuildContext context) {
    return Scrollbar(
        controller: scrollController,
        child: ScrollConfiguration(
          behavior: ScrollConfiguration.of(context).copyWith(scrollbars: false),
          child: CustomScrollView(
            controller: scrollController,
            slivers: [
              SliverToBoxAdapter(
                child: buildTop(),
              ),
              SliverToBoxAdapter(
                child: buildActions(),
              ),
              SliverToBoxAdapter(
                child: buildDescription(),
              ),
              if (widget.novel.seriesId != null)
                NovelSeriesWidget(
                    widget.novel.seriesId!, widget.novel.seriesTitle!),
              SliverPadding(
                  padding: EdgeInsets.only(
                      top: 16 + MediaQuery.of(context).padding.bottom)),
            ],
          ),
        ).padding(const EdgeInsets.symmetric(horizontal: 16)));
  }

  Widget buildTop() {
    return Card(
        child: SizedBox(
      height: 128,
      child: Row(
        children: [
          Container(
            width: 96,
            height: double.infinity,
            decoration: BoxDecoration(
              color: ColorScheme.of(context).secondaryContainer,
              borderRadius: BorderRadius.circular(4),
            ),
            clipBehavior: Clip.antiAlias,
            child: AnimatedImage(
                fit: BoxFit.cover,
                filterQuality: FilterQuality.medium,
                width: double.infinity,
                height: double.infinity,
                image: CachedImageProvider(widget.novel.image)),
          ),
          const SizedBox(width: 12),
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              mainAxisAlignment: MainAxisAlignment.start,
              children: [
                Text(widget.novel.title,
                    maxLines: 3,
                    style: const TextStyle(
                      fontSize: 16,
                      fontWeight: FontWeight.bold,
                    )),
                const SizedBox(height: 4),
                const Spacer(),
                if (widget.novel.seriesId != null)
                  Text(
                    overflow: TextOverflow.ellipsis,
                    "${"Series".tl}: ${widget.novel.seriesTitle!}",
                    style: TextStyle(
                      color: ColorScheme.of(context).primary,
                      fontSize: 12,
                    ),
                  ).paddingVertical(4)
              ],
            ),
          ),
        ],
      ),
    )).paddingTop(12);
  }

  Widget buildStats() {
    return Container(
      height: 74,
      constraints: const BoxConstraints(maxWidth: 560),
      padding: const EdgeInsets.only(bottom: 10),
      child: Row(
        children: [
          const SizedBox(width: 2),
          Expanded(
            child: Container(
              height: 68,
              decoration: BoxDecoration(
                border: Border.all(
                  color: ColorScheme.of(context).outlineVariant,
                  width: 0.6,
                ),
                borderRadius: BorderRadius.circular(4),
              ),
              padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
              child: Row(
                children: [
                  Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      const Icon(
                        FluentIcons.view,
                        size: 20,
                      ),
                      Text(
                        "Views".tl,
                        style: const TextStyle(fontSize: 12),
                      )
                    ],
                  ),
                  const SizedBox(width: 8),
                  Text(
                    widget.novel.totalViews.toString(),
                    style: TextStyle(
                      color: ColorScheme.of(context).primary,
                      fontWeight: FontWeight.w500,
                      fontSize: 18,
                    ),
                  )
                ],
              ),
            ),
          ),
          const SizedBox(width: 16),
          Expanded(
              child: Container(
            height: 68,
            decoration: BoxDecoration(
              border: Border.all(
                color: ColorScheme.of(context).outlineVariant,
                width: 0.6,
              ),
              borderRadius: BorderRadius.circular(4),
            ),
            padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
            child: Row(
              children: [
                Column(
                  mainAxisSize: MainAxisSize.min,
                  children: [
                    const Icon(
                      FluentIcons.six_point_star,
                      size: 20,
                    ),
                    Text(
                      "Favorites".tl,
                      style: const TextStyle(fontSize: 12),
                    )
                  ],
                ),
                const SizedBox(width: 8),
                Text(
                  widget.novel.totalBookmarks.toString(),
                  style: TextStyle(
                    color: ColorScheme.of(context).primary,
                    fontWeight: FontWeight.w500,
                    fontSize: 18,
                  ),
                )
              ],
            ),
          )),
          const SizedBox(width: 2),
        ],
      ),
    );
  }

  Widget buildAuthor() {
    return ConstrainedBox(
      constraints: const BoxConstraints(maxWidth: 560),
      child: Card(
        margin: const EdgeInsets.only(left: 2, right: 2, bottom: 12),
        borderColor: ColorScheme.of(context).outlineVariant.toOpacity(0.52),
        child: GestureDetector(
          behavior: HitTestBehavior.opaque,
          onTap: () {
            context.to(() => UserInfoPage(widget.novel.author.id.toString()));
          },
          child: SizedBox(
            height: 38,
            child: Row(
              children: [
                Container(
                  width: 36,
                  height: 36,
                  decoration: BoxDecoration(
                    color: ColorScheme.of(context).secondaryContainer,
                    borderRadius: BorderRadius.circular(36),
                  ),
                  clipBehavior: Clip.antiAlias,
                  child: AnimatedImage(
                    fit: BoxFit.cover,
                    width: 36,
                    height: 36,
                    filterQuality: FilterQuality.medium,
                    image: CachedImageProvider(widget.novel.author.avatar),
                  ),
                ),
                const SizedBox(width: 12),
                Expanded(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      Text(
                        widget.novel.author.name,
                        style: const TextStyle(
                          fontSize: 14,
                          fontWeight: FontWeight.bold,
                        ),
                        maxLines: 1,
                        overflow: TextOverflow.ellipsis,
                      ),
                      Text(
                        widget.novel.createDate.toString().substring(0, 10),
                        style: TextStyle(
                          fontSize: 12,
                          color: ColorScheme.of(context).outline,
                        ),
                      ),
                    ],
                  ),
                ),
                const Icon(MdIcons.chevron_right)
              ],
            ),
          ),
        ),
      ),
    );
  }

  bool isAddingFavorite = false;

  var favoriteFlyout = FlyoutController();

  Widget buildActions() {
    void favorite() async {
      if (isAddingFavorite) return;
      bool? public;
      if (!widget.novel.isBookmarked) {
        await favoriteFlyout.showFlyout(
          navigatorKey: App.rootNavigatorKey.currentState!,
          builder: (context) {
            return MenuFlyout(
              items: [
                MenuFlyoutItem(
                  text: Text("Public".tl),
                  onPressed: () {
                    public = true;
                  },
                ),
                MenuFlyoutItem(
                  text: Text("Private".tl),
                  onPressed: () {
                    public = false;
                  },
                ),
              ],
            );
          },
        );
        if (public == null) {
          return;
        }
      }
      setState(() {
        isAddingFavorite = true;
      });
      var res = widget.novel.isBookmarked
          ? await Network().deleteFavoriteNovel(widget.novel.id.toString())
          : await Network().favoriteNovel(widget.novel.id.toString(), public!);
      if (res.error) {
        if (mounted) {
          context.showToast(message: res.errorMessage ?? "Network Error");
        }
      } else {
        widget.novel.isBookmarked = !widget.novel.isBookmarked;
      }
      setState(() {
        isAddingFavorite = false;
      });
    }

    return LayoutBuilder(builder: (context, constraints) {
      final width = constraints.maxWidth;
      return Card(
        margin: const EdgeInsets.only(top: 12),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            if (width < 560) buildAuthor().toAlign(Alignment.centerLeft),
            if (width < 560) buildStats().toAlign(Alignment.centerLeft),
            if (width >= 560)
              ConstrainedBox(
                constraints: const BoxConstraints(maxWidth: 1132),
                child: Row(
                  children: [
                    Expanded(child: buildAuthor()),
                    const SizedBox(width: 12),
                    Expanded(child: buildStats()),
                  ],
                ),
              ).toAlign(Alignment.centerLeft),
            LayoutBuilder(
              builder: (context, constrains) {
                var width = constrains.maxWidth;
                bool shouldFillSpace = width < 500;
                return Row(
                  children: [
                    FilledButton(
                        child: Row(
                          children: [
                            const Icon(MdIcons.menu_book_outlined, size: 18),
                            const SizedBox(width: 12),
                            Text("Read".tl),
                            const Spacer(),
                            const Icon(MdIcons.chevron_right, size: 18)
                                .paddingTop(2),
                          ],
                        )
                            .fixWidth(shouldFillSpace
                                ? width / 2 - 4 - kFluentButtonPadding
                                : 220)
                            .fixHeight(32),
                        onPressed: () {
                          context.to(() => NovelReadingPage(widget.novel));
                        }),
                    const SizedBox(width: 16),
                    FlyoutTarget(
                      controller: favoriteFlyout,
                      child: Button(
                        onPressed: favorite,
                        child: Row(
                          mainAxisAlignment: constrains.maxWidth > 420
                              ? MainAxisAlignment.start
                              : MainAxisAlignment.center,
                          children: [
                            if (isAddingFavorite)
                              const SizedBox(
                                width: 18,
                                height: 18,
                                child: ProgressRing(
                                  strokeWidth: 2,
                                ),
                              )
                            else if (widget.novel.isBookmarked)
                              Icon(
                                MdIcons.favorite,
                                size: 18,
                                color: ColorScheme.of(context).error,
                              )
                            else
                              const Icon(MdIcons.favorite_outline, size: 18),
                            if (constrains.maxWidth > 420)
                              const SizedBox(width: 12),
                            if (constrains.maxWidth > 420) Text("Favorite".tl)
                          ],
                        )
                            .fixWidth(shouldFillSpace
                            ? width / 4 - 4 - kFluentButtonPadding
                            : 64)
                            .fixHeight(32),
                      ),
                    ),
                    const SizedBox(width: 8),
                    Button(
                        child: Row(
                          mainAxisAlignment: constrains.maxWidth > 420
                              ? MainAxisAlignment.start
                              : MainAxisAlignment.center,
                          children: [
                            const Icon(MdIcons.comment, size: 18),
                            if (constrains.maxWidth > 420)
                              const SizedBox(width: 12),
                            if (constrains.maxWidth > 420) Text("Comments".tl)
                          ],
                        )
                            .fixWidth(shouldFillSpace
                                ? width / 4 - 4 - kFluentButtonPadding
                                : 64)
                            .fixHeight(32),
                        onPressed: () {
                          CommentsPage.show(context, widget.novel.id.toString(),
                              isNovel: true);
                        }),
                  ],
                );
              },
            ).paddingHorizontal(2),
            SelectableText(
              "ID: ${widget.novel.id}",
              style: TextStyle(
                  fontSize: 13, color: ColorScheme.of(context).outline),
            ).paddingTop(8).paddingLeft(2),
          ],
        ),
      );
    });
  }

  Widget buildDescription() {
    return Card(
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            "Description".tl,
            style: const TextStyle(
              fontSize: 18,
              fontWeight: FontWeight.bold,
            ),
          ),
          const SizedBox(height: 8),
          SelectableText.rich(
              TextSpan(children: buildDescriptionText().toList())),
          const SizedBox(height: 12),
          SizedBox(
            width: double.infinity,
            child: Wrap(
              crossAxisAlignment: WrapCrossAlignment.start,
              children: [
                for (final tag in widget.novel.tags)
                  MouseRegion(
                    cursor: SystemMouseCursors.click,
                    child: GestureDetector(
                      onTap: () {
                        context.to(() => SearchNovelResultPage(tag.name));
                      },
                      child: Container(
                        margin: const EdgeInsets.only(right: 8, bottom: 6),
                        padding: const EdgeInsets.symmetric(
                            horizontal: 10, vertical: 6),
                        decoration: BoxDecoration(
                          color: ColorScheme.of(context).primaryContainer,
                          borderRadius: BorderRadius.circular(4),
                        ),
                        child: Text(
                          tag.name,
                          style: const TextStyle(fontSize: 12),
                        ),
                      ),
                    ),
                  ),
              ],
            ),
          ),
          const SizedBox(height: 12),
          Button(
              child: Row(
                children: [
                  const Icon(MdIcons.bookmark_outline, size: 18),
                  const SizedBox(width: 12),
                  Text("Related".tl)
                ],
              ).fixWidth(64).fixHeight(32),
              onPressed: () {
                context
                    .to(() => _RelatedNovelsPage(widget.novel.id.toString()));
              }),
        ],
      ),
    ).paddingTop(12);
  }

  Iterable<TextSpan> buildDescriptionText() sync* {
    var text = widget.novel.caption;
    text = text.replaceAll("<br />", "\n");
    text = text.replaceAll('\n\n', '\n');
    var labels = Queue<String>();
    var buffer = StringBuffer();
    var style = const TextStyle();
    String? link;
    Map<String, String> attributes = {};
    for (int i = 0; i < text.length; i++) {
      if (text[i] == '<' && text[i + 1] != '/') {
        var label =
            text.substring(i + 1, text.indexOf('>', i)).split(' ').first;
        labels.addLast(label);
        for (var part
            in text.substring(i + 1, text.indexOf('>', i)).split(' ')) {
          var kv = part.split('=');
          if (kv.length >= 2) {
            attributes[kv[0]] =
                kv.join('=').substring(kv[0].length + 2).replaceAll('"', '');
          }
        }
        i = text.indexOf('>', i);
      } else if (text[i] == '<' && text[i + 1] == '/') {
        var label = text.substring(i + 2, text.indexOf('>', i));
        if (label == labels.last) {
          switch (label) {
            case "strong":
              style = style.copyWith(fontWeight: FontWeight.bold);
            case "a":
              style = style.copyWith(color: ColorScheme.of(context).primary);
              link = attributes["href"];
          }
          labels.removeLast();
        }
        i = text.indexOf('>', i);
      } else {
        buffer.write(text[i]);
      }

      if (i + 1 >= text.length ||
          (labels.isEmpty &&
              (text[i + 1] == '<' || (i != 0 && text[i - 1] == '>')))) {
        var content = buffer.toString();
        var url = link;
        yield TextSpan(
            text: content,
            style: style,
            recognizer: url != null
                ? (TapGestureRecognizer()
                  ..onTap = () {
                    if (!handleLink(Uri.parse(url))) {
                      launchUrlString(url);
                    }
                  })
                : null);
        buffer.clear();
        link = null;
        attributes.clear();
        style = const TextStyle();
      }
    }
  }
}

class NovelSeriesWidget extends StatefulWidget {
  const NovelSeriesWidget(this.seriesId, this.title, {super.key});

  final int seriesId;

  final String title;

  @override
  State<NovelSeriesWidget> createState() => _NovelSeriesWidgetState();
}

class _NovelSeriesWidgetState
    extends MultiPageLoadingState<NovelSeriesWidget, Novel> {
  @override
  Widget? buildFrame(BuildContext context, Widget child) {
    return DecoratedSliver(
      decoration: BoxDecoration(
          color: FluentTheme.of(context).cardColor,
          borderRadius: BorderRadius.circular(4),
          border: Border.all(
            color: ColorScheme.of(context).outlineVariant.toOpacity(0.6),
            width: 0.5,
          )),
      sliver: SliverMainAxisGroup(slivers: [
        SliverToBoxAdapter(
          child: Text(widget.title.trim(),
              style: const TextStyle(
                fontSize: 18,
                fontWeight: FontWeight.bold,
              )).paddingTop(16).paddingLeft(12).paddingRight(12),
        ),
        const SliverPadding(padding: EdgeInsets.only(top: 8)),
        child
      ]),
    ).sliverPadding(const EdgeInsets.only(top: 16));
  }

  @override
  Widget buildLoading(BuildContext context) {
    return SliverToBoxAdapter(
      child: const Center(
        child: ProgressRing(),
      ).fixHeight(124),
    );
  }

  @override
  Widget buildError(BuildContext context, String error) {
    return SliverToBoxAdapter(
      child: Center(
        child: Text(error),
      ).fixHeight(124),
    );
  }

  @override
  Widget buildContent(BuildContext context, final List<Novel> data) {
    return SliverGridViewWithFixedItemHeight(
      itemHeight: 164,
      minCrossAxisExtent: 400,
      delegate: SliverChildBuilderDelegate(
        (context, index) {
          if (index == data.length - 1) {
            nextPage();
          }
          return NovelWidget(data[index]);
        },
        childCount: data.length,
      ),
    ).sliverPadding(const EdgeInsets.symmetric(horizontal: 8));
  }

  String? nextUrl;

  @override
  Future<Res<List<Novel>>> loadData(page) async {
    if (nextUrl == "end") {
      return Res.error("No more data");
    }
    var res =
        await Network().getNovelSeries(widget.seriesId.toString(), nextUrl);
    if (!res.error) {
      nextUrl = res.subData;
      nextUrl ??= "end";
    }
    return res;
  }
}

class NovelPageWithId extends StatefulWidget {
  const NovelPageWithId(this.id, {super.key});

  final String id;

  @override
  State<NovelPageWithId> createState() => _NovelPageWithIdState();
}

class _NovelPageWithIdState extends LoadingState<NovelPageWithId, Novel> {
  @override
  Future<Res<Novel>> loadData() async {
    return Network().getNovelDetail(widget.id);
  }

  @override
  Widget buildContent(BuildContext context, Novel data) {
    return NovelPage(data);
  }
}

class _RelatedNovelsPage extends StatefulWidget {
  const _RelatedNovelsPage(this.id);

  final String id;

  @override
  State<_RelatedNovelsPage> createState() => __RelatedNovelsPageState();
}

class __RelatedNovelsPageState
    extends LoadingState<_RelatedNovelsPage, List<Novel>> {
  @override
  Widget buildContent(BuildContext context, List<Novel> data) {
    return Column(
      children: [
        TitleBar(title: "Related Novels".tl),
        Expanded(
            child: GridViewWithFixedItemHeight(
          itemHeight: 164,
          itemCount: data.length,
          minCrossAxisExtent: 400,
          builder: (context, index) {
            return NovelWidget(data[index]);
          },
        )),
      ],
    );
  }

  @override
  Future<Res<List<Novel>>> loadData() async {
    return Network().relatedNovels(widget.id);
  }
}