import 'dart:io';

import 'package:filesize/filesize.dart';
import 'package:flutter/material.dart';
import 'package:freezer/api/download.dart';
import 'package:freezer/translations.i18n.dart';
import 'package:path/path.dart' as p;
import 'package:path_provider/path_provider.dart';
import 'cached_image.dart';

import 'dart:async';

class DownloadsScreen extends StatefulWidget {
  const DownloadsScreen({super.key});

  @override
  State<DownloadsScreen> createState() => _DownloadsScreenState();
}

class _DownloadsScreenState extends State<DownloadsScreen> {
  List<Download> downloads = [];
  late StreamSubscription _stateSubscription;

  //Sublists
  List<Download> get downloading => downloads
      .where((d) =>
          d.state == DownloadState.DOWNLOADING || d.state == DownloadState.POST)
      .toList();
  List<Download> get queued =>
      downloads.where((d) => d.state == DownloadState.NONE).toList();
  List<Download> get failed => downloads
      .where((d) =>
          d.state == DownloadState.ERROR ||
          d.state == DownloadState.DEEZER_ERROR)
      .toList();
  List<Download> get finished =>
      downloads.where((d) => d.state == DownloadState.DONE).toList();

  Future _load() async {
    //Load downloads
    List<Download> d = await downloadManager.getDownloads();
    setState(() {
      downloads = d;
    });
  }

  @override
  void initState() {
    _load();

    //Subscribe to state update
    _stateSubscription = downloadManager.serviceEvents.stream.listen((e) {
      //State change = update
      if (e['action'] == 'onStateChange') {
        setState(() => downloadManager.running = downloadManager.running);
      }
      //Progress change
      if (e['action'] == 'onProgress') {
        setState(() {
          for (Map su in e['data']) {
            try {
              downloads.firstWhere((d) => d.id == su['id']).updateFromJson(su);
            } on StateError {
              // ignore
            }
          }
        });
      }
    });

    super.initState();
  }

  @override
  void dispose() {
    _stateSubscription.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(
          title: Text('Downloads'.i18n),
          actions: [
            IconButton(
              icon: Icon(
                Icons.delete_sweep,
                semanticLabel: "Clear all".i18n,
              ),
              onPressed: () async {
                await downloadManager.removeDownloads(DownloadState.ERROR);
                await downloadManager
                    .removeDownloads(DownloadState.DEEZER_ERROR);
                await downloadManager.removeDownloads(DownloadState.DONE);
                await _load();
              },
            ),
            IconButton(
              icon: Icon(
                downloadManager.running ? Icons.stop : Icons.play_arrow,
                semanticLabel:
                    downloadManager.running ? "Stop".i18n : "Start".i18n,
              ),
              onPressed: () {
                setState(() {
                  if (downloadManager.running) {
                    downloadManager.stop();
                  } else {
                    downloadManager.start();
                  }
                });
              },
            )
          ],
        ),
        body: ListView(
          children: [
            //Now downloading
            Container(height: 2.0),
            Column(
                children: List.generate(
                    downloading.length,
                    (int i) => DownloadTile(
                          downloading[i],
                          updateCallback: () => _load(),
                        ))),
            Container(height: 8.0),

            //Queued
            if (queued.isNotEmpty)
              Text(
                'Queued'.i18n,
                textAlign: TextAlign.center,
                style: const TextStyle(
                    fontSize: 24.0, fontWeight: FontWeight.bold),
              ),
            Column(
                children: List.generate(
                    queued.length,
                    (int i) => DownloadTile(
                          queued[i],
                          updateCallback: () => _load(),
                        ))),
            if (queued.isNotEmpty)
              ListTile(
                title: Text('Clear queue'.i18n),
                leading: const Icon(Icons.delete),
                onTap: () async {
                  await downloadManager.removeDownloads(DownloadState.NONE);
                  await _load();
                },
              ),

            //Failed
            if (failed.isNotEmpty)
              Text(
                'Failed'.i18n,
                textAlign: TextAlign.center,
                style: const TextStyle(
                    fontSize: 24.0, fontWeight: FontWeight.bold),
              ),
            Column(
                children: List.generate(
                    failed.length,
                    (int i) => DownloadTile(
                          failed[i],
                          updateCallback: () => _load(),
                        ))),
            //Restart failed
            if (failed.isNotEmpty)
              ListTile(
                title: Text('Restart failed downloads'.i18n),
                leading: const Icon(Icons.restore),
                onTap: () async {
                  await downloadManager.retryDownloads();
                  await _load();
                },
              ),
            if (failed.isNotEmpty)
              ListTile(
                title: Text('Clear failed'.i18n),
                leading: const Icon(Icons.delete),
                onTap: () async {
                  await downloadManager.removeDownloads(DownloadState.ERROR);
                  await downloadManager
                      .removeDownloads(DownloadState.DEEZER_ERROR);
                  await _load();
                },
              ),

            //Finished
            if (finished.isNotEmpty)
              Text(
                'Done'.i18n,
                textAlign: TextAlign.center,
                style: const TextStyle(
                    fontSize: 24.0, fontWeight: FontWeight.bold),
              ),
            Column(
                children: List.generate(
                    finished.length,
                    (int i) => DownloadTile(
                          finished[i],
                          updateCallback: () => _load(),
                        ))),
            if (finished.isNotEmpty)
              ListTile(
                title: Text('Clear downloads history'.i18n),
                leading: const Icon(Icons.delete),
                onTap: () async {
                  await downloadManager.removeDownloads(DownloadState.DONE);
                  await _load();
                },
              ),
          ],
        ));
  }
}

class DownloadTile extends StatelessWidget {
  final Download download;
  final Function? updateCallback;
  const DownloadTile(this.download, {super.key, this.updateCallback});

  String subtitle() {
    String out = '';

    if (download.state != DownloadState.DOWNLOADING &&
        download.state != DownloadState.POST) {
      //Download type
      if (download.private) {
        out += 'Offline'.i18n;
      } else {
        out += 'External'.i18n;
      }
      out += ' | ';
    }

    if (download.state == DownloadState.POST) {
      return 'Post processing...'.i18n;
    }

    //Quality
    if (download.quality == 9) out += 'FLAC';
    if (download.quality == 3) out += 'MP3 320kbps';
    if (download.quality == 1) out += 'MP3 128kbps';

    //Downloading show progress
    if (download.state == DownloadState.DOWNLOADING) {
      out +=
          ' | ${filesize(download.received, 2)} / ${filesize(download.filesize, 2)}';
      double progress =
          download.received!.toDouble() / download.filesize!.toDouble();
      out += ' ${(progress * 100.0).toStringAsFixed(2)}%';
    }

    return out;
  }

  Future onClick(BuildContext context) async {
    if (download.state != DownloadState.DOWNLOADING &&
        download.state != DownloadState.POST) {
      showDialog(
          context: context,
          builder: (context) {
            return AlertDialog(
              title: Text('Delete'.i18n),
              content:
                  Text('Are you sure you want to delete this download?'.i18n),
              actions: [
                TextButton(
                  child: Text('Cancel'.i18n),
                  onPressed: () => Navigator.of(context).pop(),
                ),
                TextButton(
                  child: Text('Delete'.i18n),
                  onPressed: () async {
                    await downloadManager.removeDownload(download.id);
                    if (updateCallback != null) updateCallback!();
                    Navigator.of(context).pop();
                  },
                )
              ],
            );
          });
    }
  }

  //Trailing icon with state
  Widget trailing() {
    switch (download.state) {
      case DownloadState.NONE:
        return const Icon(
          Icons.query_builder,
        );
      case DownloadState.DOWNLOADING:
        return const Icon(Icons.download_rounded);
      case DownloadState.POST:
        return const Icon(Icons.miscellaneous_services);
      case DownloadState.DONE:
        return const Icon(
          Icons.done,
          color: Colors.green,
        );
      case DownloadState.DEEZER_ERROR:
        return const Icon(Icons.error, color: Colors.blue);
      case DownloadState.ERROR:
        return const Icon(Icons.error, color: Colors.red);
      default:
        return Container();
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        ListTile(
          title: Text(download.title),
          leading: CachedImage(url: download.image),
          subtitle:
              Text(subtitle(), maxLines: 1, overflow: TextOverflow.ellipsis),
          trailing: trailing(),
          onTap: () => onClick(context),
        ),
        if (download.state == DownloadState.DOWNLOADING)
          LinearProgressIndicator(value: download.progress),
        if (download.state == DownloadState.POST)
          const LinearProgressIndicator(),
      ],
    );
  }
}

class DownloadLogViewer extends StatefulWidget {
  const DownloadLogViewer({super.key});

  @override
  State<DownloadLogViewer> createState() => _DownloadLogViewerState();
}

class _DownloadLogViewerState extends State<DownloadLogViewer> {
  List<String> data = [];

  //Load log from file
  Future _load() async {
    String path =
        p.join((await getExternalStorageDirectory())!.path, 'download.log');
    File file = File(path);
    if (await file.exists()) {
      String d = await file.readAsString();
      setState(() {
        data = d.replaceAll("\r", "").split("\n");
      });
    }
  }

  //Get color by log type
  Color? color(String line) {
    if (line.startsWith('E:')) return Colors.red;
    if (line.startsWith('W:')) return Colors.orange[600];
    return null;
  }

  @override
  void initState() {
    _load();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        appBar: AppBar(title: Text('Download Log'.i18n)),
        body: ListView.builder(
          itemCount: data.length,
          itemBuilder: (context, i) {
            return Padding(
              padding: const EdgeInsets.all(8.0),
              child: Text(
                data[i],
                style: TextStyle(fontSize: 14.0, color: color(data[i])),
              ),
            );
          },
        ));
  }
}