import 'package:flutter/material.dart';
import 'package:graphql/client.dart';
import 'package:graphql_flutter/graphql_flutter.dart';
import 'package:tstor_ui/api/client.dart';
import 'package:tstor_ui/api/fs_entry.graphql.dart';
import 'package:tstor_ui/api/torrent.graphql.dart';
import 'package:tstor_ui/components/download.dart';

import 'package:tstor_ui/font/t_icons_icons.dart';
import 'package:path/path.dart' as p;
import 'package:tstor_ui/utils/bytes.dart';

class FileViewScreen extends StatefulWidget {
  final String initialPath;

  const FileViewScreen({super.key, this.initialPath = "/"});

  @override
  State<FileViewScreen> createState() => _FileViewScreenState();
}

class _FileViewScreenState extends State<FileViewScreen> {
  late String path;

  late final TextEditingController pathController;

  @override
  void initState() {
    path = widget.initialPath;
    pathController = TextEditingController(text: path);
    listDirFuture = client.query$ListDir(
      Options$Query$ListDir(
        variables: Variables$Query$ListDir(path: path),
      ),
    );
    super.initState();
  }

  void cd(String part) {
    setState(() {
      listDirFuture = null;
    });

    setState(() {
      path = p.normalize(p.join(path, part));
      pathController.text = path;
      listDirFuture = client.query$ListDir(
        Options$Query$ListDir(
          variables: Variables$Query$ListDir(path: path),
        ),
      );
    });
  }

  void refresh() {
    setState(() {
      listDirFuture = null;
    });

    setState(() {
      listDirFuture = client.query$ListDir(
        Options$Query$ListDir(
          variables: Variables$Query$ListDir(path: path),
          fetchPolicy: FetchPolicy.noCache,
        ),
      );
    });
  }

  Future<QueryResult<Query$ListDir>>? listDirFuture;

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: TextField(
          controller: pathController,
          onEditingComplete: () => cd(pathController.text),
        ),
        leading: IconButton(
          onPressed: () => cd(".."),
          icon: const Icon(Icons.arrow_upward),
        ),
        actions: [
          IconButton(
            icon: const Icon(Icons.refresh),
            onPressed: refresh,
          )
        ],
      ),
      body: FutureBuilder(
        key: GlobalKey(),
        future: listDirFuture,
        initialData: null,
        builder: (context, snapshot) {
          if (!snapshot.hasData) {
            return const Center(child: CircularProgressIndicator());
          }

          final data = snapshot.data!;

          if (data.exception != null) {
            return Text("Error\n${data.exception.toString()}");
          }

          final entry = snapshot.data?.parsedData?.fsEntry;
          if (entry == null) {
            return const Center(child: Text("Entry not exists"));
          }

          final entries = _getEntries(entry);

          if (entries == null || entries.isEmpty) {
            return const Center(child: Text("Empty dir"));
          }

          return CustomScrollView(
            slivers: [
              EntryInfoSliver(entry: entry),
              SliverList.builder(
                itemCount: entries.length,
                itemBuilder: (context, index) {
                  return DirEntry(
                    entry: entries[index],
                    onTap: (name, isFile) {
                      if (!isFile) {
                        cd(name);
                      }
                    },
                  );
                },
              ),
            ],
          );
        },
      ),
    );
  }
}

List<Fragment$DirEntry>? _getEntries(Query$ListDir$fsEntry entry) {
  switch (entry) {
    case Query$ListDir$fsEntry$$ArchiveFS entry:
      return entry.entries;
    case Query$ListDir$fsEntry$$ResolverFS entry:
      return entry.entries;
    case Query$ListDir$fsEntry$$SimpleDir entry:
      return entry.entries;
    case Query$ListDir$fsEntry$$TorrentFS entry:
      return entry.entries;
    default:
      return null;
  }
}

class DirEntry extends StatelessWidget {
  final Fragment$DirEntry entry;
  final void Function(String name, bool isFile) onTap;

  const DirEntry({super.key, required this.entry, required this.onTap});

  @override
  Widget build(BuildContext context) {
    switch (entry) {
      case Fragment$TorrentDir entry:
        final completness = entry.torrent.bytesCompleted /
            (entry.torrent.bytesCompleted + entry.torrent.bytesMissing);

        return ListTile(
          leading: const Icon(TIcons.bittorrent_bttold_logo),
          title: Text(entry.name),
          subtitle: Row(
            mainAxisSize: MainAxisSize.max,
            children: [
              Text("${completness * 100}%"),
              Expanded(child: LinearProgressIndicator(value: completness)),
              IconButton(
                onPressed: () => client.mutate$MarkTorrentDownload(
                  Options$Mutation$MarkTorrentDownload(
                    variables:
                        Variables$Mutation$MarkTorrentDownload(infohash: entry.torrent.infohash),
                  ),
                ),
                icon: const Icon(Icons.download),
              )
            ],
          ),
          onTap: () => onTap(entry.name, false),
        );
      case Fragment$DirEntry$$SimpleDir entry:
        return ListTile(
          leading: const Icon(Icons.folder),
          title: Text(entry.name),
          onTap: () => onTap(entry.name, false),
        );
      case Fragment$DirEntry$$ArchiveFS entry:
        return ListTile(
          leading: const Icon(Icons.folder_zip),
          title: Text(entry.name),
          onTap: () => onTap(entry.name, false),
        );
      case Fragment$File entry:
        return ListTile(
          leading: const Icon(Icons.insert_drive_file),
          title: Text(entry.name),
          onTap: () => onTap(entry.name, true),
        );
      default:
        return ListTile(
          leading: const Icon(Icons.question_mark),
          title: Text(entry.name),
        );
    }
  }
}

class EntryInfoSliver extends StatelessWidget {
  final Query$ListDir$fsEntry entry;

  const EntryInfoSliver({super.key, required this.entry});

  @override
  Widget build(BuildContext context) {
    switch (entry) {
      case Query$ListDir$fsEntry$$TorrentFS entry:
        final total = entry.torrent.bytesCompleted + entry.torrent.bytesMissing;

        return EntryInfoHeader(
          icon: TIcons.bittorrent_bttold_logo,
          title: Text(entry.torrent.name),
          body: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text(entry.torrent.name),
              Text("Size: ${total.bytesFormat()}"),
              Text("InfoHash: ${entry.torrent.infohash}"),
              DownloadProgress(entry.torrent.bytesCompleted, total)
            ],
          ),
          actions: [
            IconButton(
              icon: const Icon(Icons.download),
              onPressed: () => client.mutate$MarkTorrentDownload(
                Options$Mutation$MarkTorrentDownload(
                  variables: Variables$Mutation$MarkTorrentDownload(
                    infohash: entry.torrent.infohash,
                  ),
                ),
              ),
            )
          ],
        );

      default:
        return EntryInfoHeader(
          icon: Icons.folder,
          title: Text(entry.name),
          body: Text(entry.name),
        );
    }
  }
}

class EntryInfoHeader extends StatelessWidget {
  final IconData icon;
  final Widget title;
  final Widget body;
  final List<Widget>? actions;

  const EntryInfoHeader({
    super.key,
    required this.icon,
    required this.title,
    required this.body,
    this.actions,
  });

  @override
  Widget build(BuildContext context) {
    return SliverPersistentHeader(
      floating: true,
      pinned: false,
      delegate: EntryInfoSliverHeaderDelegate(icon: icon, title: title, body: body),
    );
  }
}

class EntryInfoSliverHeaderDelegate extends SliverPersistentHeaderDelegate {
  final IconData icon;
  final Widget title;
  final Widget body;
  final List<Widget>? actions;
  final double size;

  const EntryInfoSliverHeaderDelegate({
    required this.icon,
    required this.title,
    required this.body,
    this.actions,
    this.size = 150,
  });

  @override
  double get maxExtent => size;

  @override
  double get minExtent => size;

  @override
  bool shouldRebuild(covariant SliverPersistentHeaderDelegate oldDelegate) => true;

  @override
  Widget build(BuildContext context, double shrinkOffset, bool overlapsContent) {
    final content = [
      Icon(icon, size: 50),
      Expanded(child: body),
    ];

    if (actions != null && actions!.isNotEmpty) {
      content.add(ButtonBar(children: actions!));
    }

    final appBarTheme = AppBarTheme.of(context);
    final colorScheme = Theme.of(context).colorScheme;
    final onTop = (shrinkOffset == 0);

    return Material(
      color:
          onTop ? appBarTheme.backgroundColor ?? colorScheme.surface : colorScheme.surfaceContainer,
      elevation: onTop ? 0 : appBarTheme.elevation ?? 3,
      surfaceTintColor: appBarTheme.surfaceTintColor ?? colorScheme.surfaceTint,
      child: ClipRect(
        child: SizedBox(
          height: maxExtent,
          child: Column(
            children: [
              const Spacer(),
              Row(
                children: content,
              ),
              const Spacer(),
              const Divider(
                height: 1,
                thickness: 1,
              ),
            ],
          ),
        ),
      ),
    );
  }
}