async IAsyncEnumerable <IReadOnlyCollection <VideoItem> > PlaylistVideos(string playlistId, JToken playlistJson, ILogger log)
{
var index = playlistId.StartsWith("PL", StringComparison.OrdinalIgnoreCase) ? 101 : 0;
var videoIds = new HashSet <string>();
do
{
// Get videos
var newVideos = new List <VideoItem>();
foreach (var videoJson in playlistJson.SelectToken("video").NotNull())
{
var epoch = new DateTimeOffset(1970, 1, 1, 0, 0, 0, TimeSpan.Zero);
// Extract video info
var videoId = videoJson.SelectToken("encrypted_id").Value <string>();
var videoAuthor = videoJson.SelectToken("author").Value <string>();
var videoUploadDate = epoch + TimeSpan.FromSeconds(videoJson.SelectToken("time_created").Value <long>());
var videoTitle = videoJson.SelectToken("title").Value <string>();
var videoDescription = videoJson.SelectToken("description").Value <string>();
var videoDuration = TimeSpan.FromSeconds(videoJson.SelectToken("length_seconds").Value <double>());
var videoViewCount = videoJson.SelectToken("views").Value <string>().StripNonDigit().ParseLong();
var videoLikeCount = videoJson.SelectToken("likes").Value <long>();
var videoDislikeCount = videoJson.SelectToken("dislikes").Value <long>();
// Extract video keywords
var videoKeywordsJoined = videoJson.SelectToken("keywords").Value <string>();
var videoKeywords = Regex.Matches(videoKeywordsJoined, "\"[^\"]+\"|\\S+")
.Select(m => m.Value)
.Where(s => !s.IsNullOrWhiteSpace())
.Select(s => s.Trim('"'))
.ToArray();
// Create statistics and thumbnails
var videoStatistics = new Statistics(videoViewCount, videoLikeCount, videoDislikeCount);
var videoThumbnails = new ThumbnailSet(videoId);
// Add video to the list if it's not already there
if (videoIds.Add(videoId))
{
var video = new VideoItem(videoId, videoAuthor, videoUploadDate, videoTitle, videoDescription,
videoThumbnails, videoDuration, videoKeywords, videoStatistics, null, null); // TODO: is channelId in the playlist?
newVideos.Add(video);
}
}
// If no distinct videos were added to the list - break
if (newVideos.Count == 0)
{
yield break;
}
yield return(newVideos);
// Advance index
index += 100;
playlistJson = await GetPlaylistJsonAsync(playlistId, index, log);
} while (true);
}
/// <summary>
/// Initializes an instance of <see cref="Video" />.
/// </summary>
public VideoItem(string id, string author, DateTimeOffset uploadDate, string title, string description,
ThumbnailSet thumbnails, TimeSpan duration, IReadOnlyList <string> keywords, Statistics statistics)
{
Id = id;
Author = author;
UploadDate = uploadDate;
Title = title;
Description = description;
Thumbnails = thumbnails;
Duration = duration;
Keywords = keywords;
Statistics = statistics;
}
