Files
VDownload/VDownload.Core/Services/Sources/Twitch/Vod.cs

313 lines
13 KiB
C#

using Newtonsoft.Json.Linq;
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Net;
using System.Text.RegularExpressions;
using System.Threading;
using System.Threading.Tasks;
using VDownload.Core.Enums;
using VDownload.Core.Interfaces;
using VDownload.Core.Services.Sources.Twitch.Helpers;
using VDownload.Core.Structs;
using Windows.Storage;
namespace VDownload.Core.Services.Sources.Twitch
{
public class Vod : IVideoService
{
#region CONSTRUCTORS
public Vod(string id)
{
ID = id;
}
#endregion
#region PROPERTIES
public string ID { get; private set; }
public Uri VideoUrl { get; private set; }
public Metadata Metadata { get; private set; }
public BaseStream[] BaseStreams { get; private set; }
#endregion
#region STANDARD METHODS
// GET VOD METADATA
public async Task GetMetadataAsync(CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
// Get response
JToken response = null;
using (WebClient client = await Client.Helix())
{
client.QueryString.Add("id", ID);
cancellationToken.ThrowIfCancellationRequested();
response = JObject.Parse(await client.DownloadStringTaskAsync("https://api.twitch.tv/helix/videos")).GetValue("data")[0];
}
// Set parameters
GetMetadataAsync(response);
}
internal void GetMetadataAsync(JToken response)
{
// Create unified video url
VideoUrl = new Uri($"https://www.twitch.tv/videos/{ID}");
// Set metadata
Metadata = new Metadata()
{
Title = ((string)response["title"]).Replace("\n", ""),
Author = (string)response["user_name"],
Date = Convert.ToDateTime(response["created_at"]),
Duration = ParseDuration((string)response["duration"]),
Views = (long)response["view_count"],
Thumbnail = (string)response["thumbnail_url"] == string.Empty ? null : new Uri(((string)response["thumbnail_url"]).Replace("%{width}", "1920").Replace("%{height}", "1080")),
};
}
// GET VOD STREAMS
public async Task GetStreamsAsync(CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
// Get response
string[] response = null;
using (WebClient client = Client.GQL())
{
// Get video GQL access token
cancellationToken.ThrowIfCancellationRequested();
JToken videoAccessToken = JObject.Parse(await client.UploadStringTaskAsync("https://gql.twitch.tv/gql", "{\"operationName\":\"PlaybackAccessToken_Template\",\"query\":\"query PlaybackAccessToken_Template($login: String!, $isLive: Boolean!, $vodID: ID!, $isVod: Boolean!, $playerType: String!) { streamPlaybackAccessToken(channelName: $login, params: {platform: \\\"web\\\", playerBackend: \\\"mediaplayer\\\", playerType: $playerType}) @include(if: $isLive) { value signature __typename } videoPlaybackAccessToken(id: $vodID, params: {platform: \\\"web\\\", playerBackend: \\\"mediaplayer\\\", playerType: $playerType}) @include(if: $isVod) { value signature __typename }}\",\"variables\":{\"isLive\":false,\"login\":\"\",\"isVod\":true,\"vodID\":\"" + ID + "\",\"playerType\":\"embed\"}}"))["data"]["videoPlaybackAccessToken"];
// Get video streams
cancellationToken.ThrowIfCancellationRequested();
response = (await client.DownloadStringTaskAsync($"http://usher.twitch.tv/vod/{ID}?nauth={videoAccessToken["value"]}&nauthsig={videoAccessToken["signature"]}&allow_source=true&player=twitchweb")).Split("\n");
}
// Init streams list
List<BaseStream> streams = new List<BaseStream>();
// Stream data line2 regular expression
Regex streamDataL2Regex = new Regex(@"^#EXT-X-STREAM-INF:BANDWIDTH=\d+,CODECS=""\S+,\S+"",RESOLUTION=\d+x(?<height>\d+),VIDEO=""\w+""(,FRAME-RATE=(?<frame_rate>\d+.\d+))?");
// Parse response
for (int i = 2; i < response.Length; i += 3)
{
// Parse line 2
Match line2 = streamDataL2Regex.Match(response[i + 1]);
// Create stream
BaseStream stream = new BaseStream()
{
Url = new Uri(response[i + 2]),
Height = int.Parse(line2.Groups["height"].Value),
FrameRate = line2.Groups["frame_rate"].Value != string.Empty ? (int)Math.Round(double.Parse(line2.Groups["frame_rate"].Value)) : 0,
};
// Add stream
streams.Add(stream);
}
// Set streams
BaseStreams = streams.ToArray();
}
// DOWNLOAD AND TRANSCODE VOD
public async Task<StorageFile> DownloadAndTranscodeAsync(StorageFolder downloadingFolder, BaseStream baseStream, MediaFileExtension extension, MediaType mediaType, TimeSpan trimStart, TimeSpan trimEnd, CancellationToken cancellationToken = default)
{
// Invoke DownloadingStarted event
cancellationToken.ThrowIfCancellationRequested();
DownloadingProgressChanged(this, new EventArgs.ProgressChangedEventArgs(0));
// Get video chunks
cancellationToken.ThrowIfCancellationRequested();
List<(Uri ChunkUrl, TimeSpan ChunkDuration)> chunksList = await ExtractChunksFromM3U8Async(baseStream.Url, cancellationToken);
// Changeable duration
TimeSpan duration = Metadata.Duration;
// Passive trim
if ((bool)Config.GetValue("twitch_vod_passive_trim") && trimStart != TimeSpan.Zero && trimEnd != duration) (trimStart, trimEnd, duration) = PassiveVideoTrim(chunksList, trimStart, trimEnd, Metadata.Duration);
// Download
cancellationToken.ThrowIfCancellationRequested();
StorageFile rawFile = await downloadingFolder.CreateFileAsync("raw.ts");
double chunksDownloaded = 0;
Task<byte[]> downloadTask;
Task writeTask;
cancellationToken.ThrowIfCancellationRequested();
downloadTask = DownloadChunkAsync(chunksList[0].ChunkUrl);
await downloadTask;
for (int i = 1; i < chunksList.Count; i++)
{
cancellationToken.ThrowIfCancellationRequested();
writeTask = WriteChunkToFileAsync(rawFile, downloadTask.Result);
downloadTask = DownloadChunkAsync(chunksList[i].ChunkUrl);
await Task.WhenAll(writeTask, downloadTask);
DownloadingProgressChanged(this, new EventArgs.ProgressChangedEventArgs(++chunksDownloaded * 100 / chunksList.Count));
}
cancellationToken.ThrowIfCancellationRequested();
await WriteChunkToFileAsync(rawFile, downloadTask.Result);
DownloadingProgressChanged(this, new EventArgs.ProgressChangedEventArgs(100, true));
// Processing
cancellationToken.ThrowIfCancellationRequested();
StorageFile outputFile = await downloadingFolder.CreateFileAsync($"transcoded.{extension.ToString().ToLower()}");
MediaProcessor mediaProcessor = new MediaProcessor();
mediaProcessor.ProgressChanged += ProcessingProgressChanged;
Task mediaProcessorTask;
if (trimStart == TimeSpan.Zero && trimEnd == duration) mediaProcessorTask = mediaProcessor.Run(rawFile, extension, mediaType, outputFile, cancellationToken: cancellationToken);
else if (trimStart == TimeSpan.Zero) mediaProcessorTask = mediaProcessor.Run(rawFile, extension, mediaType, outputFile, trimStart: trimStart, cancellationToken: cancellationToken);
else if (trimEnd == duration) mediaProcessorTask = mediaProcessor.Run(rawFile, extension, mediaType, outputFile, trimEnd: trimEnd, cancellationToken: cancellationToken);
else mediaProcessorTask = mediaProcessor.Run(rawFile, extension, mediaType, outputFile, trimStart, trimEnd, cancellationToken);
await mediaProcessorTask;
// Return output file
return outputFile;
}
#endregion
#region LOCAL METHODS
// GET CHUNKS DATA FROM M3U8 PLAYLIST
private static async Task<List<(Uri ChunkUrl, TimeSpan ChunkDuration)>> ExtractChunksFromM3U8Async(Uri streamUrl, CancellationToken cancellationToken = default)
{
cancellationToken.ThrowIfCancellationRequested();
// Get response
string response = null;
using (WebClient client = Client.GQL())
{
response = await client.DownloadStringTaskAsync(streamUrl);
}
// Create dictionary
List<(Uri ChunkUrl, TimeSpan ChunkDuration)> chunks = new List<(Uri ChunkUrl, TimeSpan ChunkDuration)>();
// Chunk data regular expression
Regex chunkDataRegex = new Regex(@"#EXTINF:(?<duration>\d+.\d+),\n(?<filename>\S+.ts)");
// Chunks location
string chunkLocationPath = streamUrl.AbsoluteUri.Replace(System.IO.Path.GetFileName(streamUrl.AbsoluteUri), "");
// Pack data into dictionary
foreach (Match chunk in chunkDataRegex.Matches(response))
{
Uri chunkUrl = new Uri($"{chunkLocationPath}{chunk.Groups["filename"].Value}");
TimeSpan chunkDuration = TimeSpan.FromSeconds(double.Parse(chunk.Groups["duration"].Value));
chunks.Add((chunkUrl, chunkDuration));
}
// Return chunks data
return chunks;
}
// PASSIVE TRIM
private static (TimeSpan NewTrimStart, TimeSpan NewTrimEnd, TimeSpan NewDuration) PassiveVideoTrim(List<(Uri ChunkUrl, TimeSpan ChunkDuration)> chunksList, TimeSpan trimStart, TimeSpan trimEnd, TimeSpan duration)
{
// Copy duration
TimeSpan newDuration = duration;
// Trim at start
while (chunksList[0].ChunkDuration <= trimStart)
{
trimStart = trimStart.Subtract(chunksList[0].ChunkDuration);
trimEnd = trimEnd.Subtract(chunksList[0].ChunkDuration);
newDuration = newDuration.Subtract(chunksList[0].ChunkDuration);
chunksList.RemoveAt(0);
}
// Trim at end
while (chunksList.Last().ChunkDuration <= newDuration.Subtract(trimEnd))
{
newDuration = newDuration.Subtract(chunksList.Last().ChunkDuration);
chunksList.RemoveAt(chunksList.Count - 1);
}
// Return data
return (trimStart, trimEnd, newDuration);
}
// DOWNLOAD CHUNK
private static async Task<byte[]> DownloadChunkAsync(Uri chunkUrl, CancellationToken cancellationToken = default)
{
int retriesCount = 0;
while (true)
{
cancellationToken.ThrowIfCancellationRequested();
try
{
using (WebClient client = new WebClient())
{
return await client.DownloadDataTaskAsync(chunkUrl);
}
}
catch (WebException wex)
{
if ((bool)Config.GetValue("twitch_vod_downloading_chunk_retry_after_error") && retriesCount < (int)Config.GetValue("twitch_vod_downloading_chunk_max_retries"))
{
retriesCount++;
await Task.Delay((int)Config.GetValue("twitch_vod_downloading_chunk_retries_delay"));
}
else throw wex;
}
}
}
// WRITE CHUNK TO FILE
private static Task WriteChunkToFileAsync(StorageFile file, byte[] chunk)
{
return Task.Factory.StartNew(() =>
{
using (var stream = new System.IO.FileStream(file.Path, System.IO.FileMode.Append))
{
stream.Write(chunk, 0, chunk.Length);
stream.Close();
}
});
}
// PARSE DURATION
private static TimeSpan ParseDuration(string duration)
{
char[] separators = { 'h', 'm', 's' };
string[] durationParts = duration.Split(separators, StringSplitOptions.RemoveEmptyEntries).Reverse().ToArray();
TimeSpan timeSpan = new TimeSpan(
durationParts.Count() > 2 ? int.Parse(durationParts[2]) : 0,
durationParts.Count() > 1 ? int.Parse(durationParts[1]) : 0,
int.Parse(durationParts[0]));
return timeSpan;
}
#endregion
#region EVENT HANDLERS
public event EventHandler<EventArgs.ProgressChangedEventArgs> DownloadingProgressChanged;
public event EventHandler<EventArgs.ProgressChangedEventArgs> ProcessingProgressChanged;
#endregion
}
}