youtube_explode/lib/src/reverse_engineering/pages/channel_upload_page.dart

import 'package:collection/collection.dart';
import 'package:html/parser.dart' as parser;

import '../../channels/channel_video.dart';
import '../../exceptions/exceptions.dart';
import '../../extensions/helpers_extension.dart';
import '../../retry.dart';
import '../../videos/videos.dart';
import '../models/initial_data.dart';
import '../models/youtube_page.dart';
import '../youtube_http_client.dart';

///
class ChannelUploadPage extends YoutubePage<_InitialData> {
  ///
  final String channelId;

  late final List<ChannelVideo> uploads = initialData.uploads;

  /// InitialData
  ChannelUploadPage.id(this.channelId, _InitialData? initialData)
      : super(null, null, initialData);

  ///
  Future<ChannelUploadPage?> nextPage(YoutubeHttpClient httpClient) async {
    if (initialData.token.isEmpty) {
      return null;
    }

    final data = await httpClient.sendPost('browse', initialData.token);
    return ChannelUploadPage.id(channelId, _InitialData(data));
  }

  ///
  static Future<ChannelUploadPage> get(
      YoutubeHttpClient httpClient, String channelId, String sorting) {
    var url =
        'https://www.youtube.com/channel/$channelId/videos?view=0&sort=$sorting&flow=grid';
    return retry(httpClient, () async {
      var raw = await httpClient.getString(url);
      return ChannelUploadPage.parse(raw, channelId);
    });
  }

  ///
  ChannelUploadPage.parse(String raw, this.channelId)
      : super(parser.parse(raw), (root) => _InitialData(root));
}

class _InitialData extends InitialData {
  _InitialData(JsonMap root) : super(root);

  late final JsonMap? continuationContext = getContinuationContext();

  late final String token = continuationContext?.getT<String>('token') ?? '';

  late final List<ChannelVideo> uploads = _getUploads();

  List<ChannelVideo> _getUploads() {
    final content = getContentContext();
    if (content.isEmpty) {
      return const <ChannelVideo>[];
    }
    return content.map(_parseContent).whereNotNull().toList();
  }

  List<JsonMap> getContentContext() {
    List<JsonMap>? context;
    if (root.containsKey('contents')) {
      final render = root
          .get('contents')
          ?.get('twoColumnBrowseResultsRenderer')
          ?.getList('tabs')
          ?.map((e) => e['tabRenderer'])
          .cast<JsonMap>()
          .firstWhereOrNull((e) => e['selected'] as bool)
          ?.get('content')
          ?.get('sectionListRenderer')
          ?.getList('contents')
          ?.firstOrNull
          ?.get('itemSectionRenderer')
          ?.getList('contents')
          ?.firstOrNull;

      if (render?.containsKey('gridRenderer') ?? false) {
        context =
            render?.get('gridRenderer')?.getList('items')?.cast<JsonMap>();
      } else if (render?.containsKey('messageRenderer') ?? false) {
        // Workaround for no-videos.
        context = const [];
      }
    }
    if (context == null && root.containsKey('onResponseReceivedActions')) {
      context = root
          .getList('onResponseReceivedActions')
          ?.firstOrNull
          ?.get('appendContinuationItemsAction')
          ?.getList('continuationItems')
          ?.cast<JsonMap>();
    }
    if (context == null) {
      throw FatalFailureException('Failed to get initial data context.');
    }
    return context;
  }

  JsonMap? getContinuationContext() {
    if (root.containsKey('contents')) {
      return root
          .get('contents')
          ?.get('twoColumnBrowseResultsRenderer')
          ?.getList('tabs')
          ?.map((e) => e['tabRenderer'])
          .cast<JsonMap>()
          .firstWhereOrNull((e) => e['selected'] as bool)
          ?.get('content')
          ?.get('sectionListRenderer')
          ?.getList('contents')
          ?.firstOrNull
          ?.get('itemSectionRenderer')
          ?.getList('contents')
          ?.firstOrNull
          ?.get('gridRenderer')
          ?.getList('items')
          ?.firstWhereOrNull((e) => e['continuationItemRenderer'] != null)
          ?.get('continuationItemRenderer')
          ?.get('continuationEndpoint')
          ?.get('continuationCommand');
    }
    if (root.containsKey('onResponseReceivedActions')) {
      return root
          .getList('onResponseReceivedActions')
          ?.firstOrNull
          ?.get('appendContinuationItemsAction')
          ?.getList('continuationItems')
          ?.firstWhereOrNull((e) => e['continuationItemRenderer'] != null)
          ?.get('continuationItemRenderer')
          ?.get('continuationEndpoint')
          ?.get('continuationCommand');
    }
    return null;
  }

  ChannelVideo? _parseContent(JsonMap? content) {
    if (content == null || !content.containsKey('gridVideoRenderer')) {
      return null;
    }

    var video = content.get('gridVideoRenderer')!;
    return ChannelVideo(
      VideoId(video.getT<String>('videoId')!),
      video.get('title')?.getT<String>('simpleText') ??
          video.get('title')?.getList('runs')?.map((e) => e['text']).join() ??
          '',
      video
              .getList('thumbnailOverlays')
              ?.firstOrNull
              ?.get('thumbnailOverlayTimeStatusRenderer')
              ?.get('text')
              ?.getT<String>('simpleText')
              ?.toDuration() ??
          Duration.zero,
      video.get('thumbnail')?.getList('thumbnails')?.last.getT<String>('url') ??
          '',
      video.get('publishedTimeText')?.getT<String>('simpleText') ?? '',
      video.get('viewCountText')?.getT<String>('simpleText')?.parseInt() ?? 0,
    );
  }
}

//