quickgui/lib/src/pages/downloader.dart

import 'dart:async';
import 'dart:convert';
import 'dart:io';

import 'package:desktop_notifications/desktop_notifications.dart';
import 'package:flutter/material.dart';
import 'package:gettext_i18n/gettext_i18n.dart';
import 'package:platform_ui/platform_ui.dart';
import 'package:quickgui/src/widgets/title_bar.dart';

import '../model/operating_system.dart';
import '../model/option.dart';
import '../model/version.dart';
import '../widgets/downloader/download_label.dart';
import '../widgets/downloader/download_progress_bar.dart';

class Downloader extends StatefulWidget {
  const Downloader({
    Key? key,
    required this.operatingSystem,
    required this.version,
    this.option,
  }) : super(key: key);

  final OperatingSystem operatingSystem;
  final Version version;
  final Option? option;

  @override
  _DownloaderState createState() => _DownloaderState();
}

class _DownloaderState extends State<Downloader> {
  final notificationsClient = NotificationsClient();
  final wgetPattern = RegExp("( [0-9.]+%)");
  final macRecoveryPattern = RegExp("([0-9]+\\.[0-9])");
  final ariaPattern = RegExp("([0-9.]+%)");
  late final Stream<double> _progressStream;
  bool _downloadFinished = false;
  var controller = StreamController<double>();
  Process? _process;

  @override
  void initState() {
    _progressStream = progressStream();
    super.initState();
  }

  void parseWgetProgress(String line) {
    var matches = wgetPattern.allMatches(line).toList();
    if (matches.isNotEmpty) {
      var percent = matches[0].group(1);
      if (percent != null) {
        var value = double.parse(percent.replaceAll('%', '')) / 100.0;
        controller.add(value);
      }
    }
  }

  void parseAriaProgress(String line) {
    var matches = ariaPattern.allMatches(line).toList();
    if (matches.isNotEmpty) {
      var percent = matches[0].group(1);
      if (percent != null) {
        var value = double.parse(percent.replaceAll('%', '')) / 100.0;
        controller.add(value);
      }
    }
  }

  void parseMacRecoveryProgress(String line) {
    var matches = macRecoveryPattern.allMatches(line).toList();
    if (matches.isNotEmpty) {
      var size = matches[0].group(1);
      if (size != null) {
        var value = double.parse(size);
        controller.add(value);
      }
    }
  }

  Stream<double> progressStream() {
    var options = [widget.operatingSystem.code, widget.version.version];
    if (widget.option != null) {
      options.add(widget.option!.option);
    }
    Process.start('quickget', options).then((process) {
      if (widget.option!.downloader == 'wget') {
        process.stderr.transform(utf8.decoder).forEach(parseWgetProgress);
      } else if (widget.option!.downloader == 'zsync') {
        controller.add(-1);
      } else if (widget.option!.downloader == 'macrecovery') {
        process.stdout
            .transform(utf8.decoder)
            .forEach(parseMacRecoveryProgress);
      } else if (widget.option!.downloader == 'aria2c') {
        process.stderr.transform(utf8.decoder).forEach(parseAriaProgress);
      }

      process.exitCode.then((value) {
        bool _cancelled = value.isNegative;
        controller.close();
        setState(() {
          _downloadFinished = true;
          notificationsClient.notify(
            _cancelled
                ? context.t('Download cancelled')
                : context.t('Download complete'),
            body: _cancelled
                ? context.t(
                    'Download of {0} has been canceled.',
                    args: [widget.operatingSystem.name],
                  )
                : context.t(
                    'Download of {0} has completed.',
                    args: [widget.operatingSystem.name],
                  ),
            appName: 'Quickgui',
            expireTimeoutMs: 10000, /* 10 seconds */
          );
        });
      });

      setState(() {
        _process = process;
      });
    });
    return controller.stream;
  }

  @override
  Widget build(BuildContext context) {
    return PlatformScaffold(
      appBar: TitleBar(
        title: PlatformText.subheading(
          context.t('Downloading {0}', args: [
            '${widget.operatingSystem.name} ${widget.version.version}' +
                (widget.option!.option.isNotEmpty
                    ? ' (${widget.option!.option})'
                    : '')
          ]),
        ),
        automaticallyImplyLeading: false,
      ),
      body: Center(
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.center,
          children: [
            Expanded(
              child: StreamBuilder(
                stream: _progressStream,
                builder: (context, AsyncSnapshot<double> snapshot) {
                  var data = !snapshot.hasData ||
                          widget.option!.downloader != 'wget' ||
                          widget.option!.downloader != 'aria2c'
                      ? null
                      : snapshot.data;
                  return Column(
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                      DownloadLabel(
                        downloadFinished: _downloadFinished,
                        data: snapshot.hasData ? snapshot.data : null,
                        downloader: widget.option!.downloader,
                      ),
                      DownloadProgressBar(
                        downloadFinished: _downloadFinished,
                        data: snapshot.hasData ? data : null,
                      ),
                      Padding(
                        padding: const EdgeInsets.only(top: 32),
                        child: PlatformText(context.t('Target folder : {0}',
                            args: [Directory.current.path])),
                      ),
                    ],
                  );
                },
              ),
            ),
            PlatformFilledButton(
              onPressed: () {
                if (!_downloadFinished) {
                  _process?.kill();
                } else {
                  Navigator.of(context).pop();
                }
              },
              style: ButtonStyle(
                backgroundColor: MaterialStateProperty.all(Colors.red[400]),
              ),
              child: _downloadFinished
                  ? PlatformText(
                      context.t('Dismiss'),
                      style: const TextStyle(color: Colors.white),
                    )
                  : PlatformText(
                      context.t('Cancel'),
                      style: const TextStyle(color: Colors.white),
                    ),
            ),
            const SizedBox(height: 16),
          ],
        ),
      ),
    );
  }
}