jellyfin/MediaBrowser.Providers/MediaInfo/SubtitleResolver.cs
2021-11-27 20:35:18 +01:00

236 lines
9.5 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using MediaBrowser.Controller.Entities;
using MediaBrowser.Controller.Providers;
using MediaBrowser.Model.Entities;
using MediaBrowser.Model.Globalization;
namespace MediaBrowser.Providers.MediaInfo
{
/// <summary>
/// Resolves external subtitles for videos.
/// </summary>
public class SubtitleResolver
{
private readonly ILocalizationManager _localization;
/// <summary>
/// Initializes a new instance of the <see cref="SubtitleResolver"/> class.
/// </summary>
/// <param name="localization">The localization manager.</param>
public SubtitleResolver(ILocalizationManager localization)
{
_localization = localization;
}
/// <summary>
/// Retrieves the external subtitle streams for the provided video.
/// </summary>
/// <param name="video">The video to search from.</param>
/// <param name="startIndex">The stream index to start adding subtitle streams at.</param>
/// <param name="directoryService">The directory service to search for files.</param>
/// <param name="clearCache">True if the directory service cache should be cleared before searching.</param>
/// <returns>The external subtitle streams located.</returns>
public List<MediaStream> GetExternalSubtitleStreams(
Video video,
int startIndex,
IDirectoryService directoryService,
bool clearCache)
{
var streams = new List<MediaStream>();
if (!video.IsFileProtocol)
{
return streams;
}
AddExternalSubtitleStreams(streams, video.ContainingFolderPath, video.Path, startIndex, directoryService, clearCache);
startIndex += streams.Count;
string folder = video.GetInternalMetadataPath();
if (!Directory.Exists(folder))
{
return streams;
}
try
{
AddExternalSubtitleStreams(streams, folder, video.Path, startIndex, directoryService, clearCache);
}
catch (IOException)
{
}
return streams;
}
/// <summary>
/// Locates the external subtitle files for the provided video.
/// </summary>
/// <param name="video">The video to search from.</param>
/// <param name="directoryService">The directory service to search for files.</param>
/// <param name="clearCache">True if the directory service cache should be cleared before searching.</param>
/// <returns>The external subtitle file paths located.</returns>
public IEnumerable<string> GetExternalSubtitleFiles(
Video video,
IDirectoryService directoryService,
bool clearCache)
{
if (!video.IsFileProtocol)
{
yield break;
}
var streams = GetExternalSubtitleStreams(video, 0, directoryService, clearCache);
foreach (var stream in streams)
{
yield return stream.Path;
}
}
/// <summary>
/// Extracts the subtitle files from the provided list and adds them to the list of streams.
/// </summary>
/// <param name="streams">The list of streams to add external subtitles to.</param>
/// <param name="videoPath">The path to the video file.</param>
/// <param name="startIndex">The stream index to start adding subtitle streams at.</param>
/// <param name="files">The files to add if they are subtitles.</param>
public void AddExternalSubtitleStreams(
List<MediaStream> streams,
string videoPath,
int startIndex,
IReadOnlyList<string> files)
{
var videoFileNameWithoutExtension = NormalizeFilenameForSubtitleComparison(videoPath);
for (var i = 0; i < files.Count; i++)
{
var fullName = files[i];
var extension = Path.GetExtension(fullName.AsSpan());
if (!IsSubtitleExtension(extension))
{
continue;
}
var fileNameWithoutExtension = NormalizeFilenameForSubtitleComparison(fullName);
MediaStream mediaStream;
// The subtitle filename must either be equal to the video filename or start with the video filename followed by a dot
if (videoFileNameWithoutExtension.Equals(fileNameWithoutExtension, StringComparison.OrdinalIgnoreCase))
{
mediaStream = new MediaStream
{
Index = startIndex++,
Type = MediaStreamType.Subtitle,
IsExternal = true,
Path = fullName
};
}
else if (fileNameWithoutExtension.Length > videoFileNameWithoutExtension.Length
&& fileNameWithoutExtension[videoFileNameWithoutExtension.Length] == '.'
&& fileNameWithoutExtension.StartsWith(videoFileNameWithoutExtension, StringComparison.OrdinalIgnoreCase))
{
var isForced = fullName.Contains(".forced.", StringComparison.OrdinalIgnoreCase)
|| fullName.Contains(".foreign.", StringComparison.OrdinalIgnoreCase);
var isDefault = fullName.Contains(".default.", StringComparison.OrdinalIgnoreCase);
// Support xbmc naming conventions - 300.spanish.srt
var languageSpan = fileNameWithoutExtension;
while (languageSpan.Length > 0)
{
var lastDot = languageSpan.LastIndexOf('.');
if (lastDot < videoFileNameWithoutExtension.Length)
{
languageSpan = ReadOnlySpan<char>.Empty;
break;
}
var currentSlice = languageSpan[lastDot..];
if (currentSlice.Equals(".default", StringComparison.OrdinalIgnoreCase)
|| currentSlice.Equals(".forced", StringComparison.OrdinalIgnoreCase)
|| currentSlice.Equals(".foreign", StringComparison.OrdinalIgnoreCase))
{
languageSpan = languageSpan[..lastDot];
continue;
}
languageSpan = languageSpan[(lastDot + 1)..];
break;
}
var language = languageSpan.ToString();
if (string.IsNullOrWhiteSpace(language))
{
language = null;
}
else
{
// Try to translate to three character code
// Be flexible and check against both the full and three character versions
var culture = _localization.FindLanguageInfo(language);
language = culture == null ? language : culture.ThreeLetterISOLanguageName;
}
mediaStream = new MediaStream
{
Index = startIndex++,
Type = MediaStreamType.Subtitle,
IsExternal = true,
Path = fullName,
Language = language,
IsForced = isForced,
IsDefault = isDefault
};
}
else
{
continue;
}
mediaStream.Codec = extension.TrimStart('.').ToString().ToLowerInvariant();
streams.Add(mediaStream);
}
}
private static bool IsSubtitleExtension(ReadOnlySpan<char> extension)
{
return extension.Equals(".srt", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".ssa", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".ass", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".sub", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".vtt", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".smi", StringComparison.OrdinalIgnoreCase)
|| extension.Equals(".sami", StringComparison.OrdinalIgnoreCase);
}
private static ReadOnlySpan<char> NormalizeFilenameForSubtitleComparison(string filename)
{
// Try to account for sloppy file naming
filename = filename.Replace("_", string.Empty, StringComparison.Ordinal);
filename = filename.Replace(" ", string.Empty, StringComparison.Ordinal);
return Path.GetFileNameWithoutExtension(filename.AsSpan());
}
private void AddExternalSubtitleStreams(
List<MediaStream> streams,
string folder,
string videoPath,
int startIndex,
IDirectoryService directoryService,
bool clearCache)
{
var files = directoryService.GetFilePaths(folder, clearCache, true);
AddExternalSubtitleStreams(streams, videoPath, startIndex, files);
}
}
}