1 files changed, 258 insertions, 0 deletions
diff --git a/tests/Jellyfin.Controller.Tests/MediaEncoding/EncodingHelperTests.cs b/tests/Jellyfin.Controller.Tests/MediaEncoding/EncodingHelperTests.cs
new file mode 100644
index 0000000000..d7ae6a8a18
--- /dev/null
+++ b/tests/Jellyfin.Controller.Tests/MediaEncoding/EncodingHelperTests.cs
@@ -0,0 +1,258 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using Jellyfin.Data.Enums;
+using MediaBrowser.Common.Configuration;
+using MediaBrowser.Controller.IO;
+using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.MediaEncoding;
+using MediaBrowser.Controller.Streaming;
+using MediaBrowser.Model.Configuration;
+using MediaBrowser.Model.Dlna;
+using MediaBrowser.Model.Dto;
+using MediaBrowser.Model.Entities;
+using Moq;
+using Xunit;
+
+using IConfiguration = Microsoft.Extensions.Configuration.IConfiguration;
+
+namespace Jellyfin.Controller.Tests.MediaEncoding;
+
+public class EncodingHelperTests
+{
+    [Fact]
+    public void GetMapArgs_NoSubtitle_ExcludesAllSubs()
+    {
+        var state = BuildState(subtitle: null, deliveryMethod: null);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map -0:s", args, StringComparison.Ordinal);
+        Assert.DoesNotContain("-map 1:", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_InternalSrt_MapsFromPrimaryInput()
+    {
+        var sub = new MediaStream { Index = 2, Type = MediaStreamType.Subtitle, Codec = "srt" };
+        var state = BuildState(sub, SubtitleDeliveryMethod.Embed);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 0:2", args, StringComparison.Ordinal);
+        Assert.DoesNotContain("-map 1:", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_InternalSubAtHigherIndex_MapsCorrectIndex()
+    {
+        var sub0 = new MediaStream { Index = 2, Type = MediaStreamType.Subtitle, Codec = "srt" };
+        var sub1 = new MediaStream { Index = 3, Type = MediaStreamType.Subtitle, Codec = "ass" };
+        var state = BuildState(sub1, SubtitleDeliveryMethod.Embed, additionalStreams: [sub0, sub1]);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 0:3", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_ExternalSrt_MapsFirstStreamFromInput1()
+    {
+        var sub = new MediaStream
+        {
+            Index = 2,
+            Type = MediaStreamType.Subtitle,
+            Codec = "srt",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.en.srt"
+        };
+        var state = BuildState(sub, SubtitleDeliveryMethod.Embed);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 1:0", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_SecondExternalSrt_StillMaps1Colon0()
+    {
+        // Two separate .srt files — selecting the second one still maps 1:0
+        // because Jellyfin feeds only the selected file as ffmpeg input 1.
+        var ext1 = new MediaStream
+        {
+            Index = 2,
+            Type = MediaStreamType.Subtitle,
+            Codec = "srt",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.en.srt"
+        };
+        var ext2 = new MediaStream
+        {
+            Index = 3,
+            Type = MediaStreamType.Subtitle,
+            Codec = "srt",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.fr.srt"
+        };
+        var state = BuildState(ext2, SubtitleDeliveryMethod.Embed, additionalStreams: [ext1, ext2]);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 1:0", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_MksFirstTrack_MapsInFileIndex0()
+    {
+        var mks0 = new MediaStream
+        {
+            Index = 2,
+            Type = MediaStreamType.Subtitle,
+            Codec = "subrip",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.mks"
+        };
+        var mks1 = new MediaStream
+        {
+            Index = 3,
+            Type = MediaStreamType.Subtitle,
+            Codec = "ass",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.mks"
+        };
+        var state = BuildState(mks0, SubtitleDeliveryMethod.Embed, additionalStreams: [mks0, mks1]);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 1:0", args, StringComparison.Ordinal);
+    }
+
+    [Fact]
+    public void GetMapArgs_MksSecondTrack_MapsInFileIndex1()
+    {
+        var mks0 = new MediaStream
+        {
+            Index = 2,
+            Type = MediaStreamType.Subtitle,
+            Codec = "subrip",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.mks"
+        };
+        var mks1 = new MediaStream
+        {
+            Index = 3,
+            Type = MediaStreamType.Subtitle,
+            Codec = "ass",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.mks"
+        };
+        var mks2 = new MediaStream
+        {
+            Index = 4,
+            Type = MediaStreamType.Subtitle,
+            Codec = "subrip",
+            IsExternal = true,
+            SupportsExternalStream = true,
+            Path = "/media/movie.mks"
+        };
+        var state = BuildState(mks1, SubtitleDeliveryMethod.Embed, additionalStreams: [mks0, mks1, mks2]);
+        var args = CreateHelper().GetMapArgs(state);
+
+        Assert.Contains("-map 1:1", args, StringComparison.Ordinal);
+    }
+
+    [Theory]
+    [InlineData(SubtitleDeliveryMethod.Embed, true, "movie.idx")]
+    [InlineData(SubtitleDeliveryMethod.Encode, true, "movie.idx")]
+    [InlineData(SubtitleDeliveryMethod.Embed, false, "movie.sub")]
+    [InlineData(SubtitleDeliveryMethod.Encode, false, "movie.sub")]
+    public void GetInputArgument_VobSub_UsesCorrectPath(
+        SubtitleDeliveryMethod deliveryMethod,
+        bool createIdxFile,
+        string expectedFilename)
+    {
+        var tempDir = Directory.CreateTempSubdirectory("jellyfin-test-");
+        try
+        {
+            var subFile = Path.Combine(tempDir.FullName, "movie.sub");
+            File.WriteAllText(subFile, "dummy");
+
+            if (createIdxFile)
+            {
+                File.WriteAllText(Path.Combine(tempDir.FullName, "movie.idx"), "dummy");
+            }
+
+            var sub = new MediaStream
+            {
+                Index = 2,
+                Type = MediaStreamType.Subtitle,
+                Codec = "dvdsub",
+                IsExternal = true,
+                SupportsExternalStream = true,
+                Path = subFile
+            };
+            var state = BuildState(sub, deliveryMethod);
+            var inputArgs = CreateHelper().GetInputArgument(state, new EncodingOptions(), null);
+
+            Assert.Contains(expectedFilename, inputArgs, StringComparison.Ordinal);
+        }
+        finally
+        {
+            tempDir.Delete(true);
+        }
+    }
+
+    private static EncodingJobInfo BuildState(
+        MediaStream? subtitle,
+        SubtitleDeliveryMethod? deliveryMethod,
+        MediaStream[]? additionalStreams = null)
+    {
+        var video = new MediaStream { Index = 0, Type = MediaStreamType.Video, Codec = "h264" };
+        var audio = new MediaStream { Index = 1, Type = MediaStreamType.Audio, Codec = "aac" };
+        var streams = new List<MediaStream> { video, audio };
+
+        if (additionalStreams is not null)
+        {
+            streams.AddRange(additionalStreams);
+        }
+        else if (subtitle is not null)
+        {
+            streams.Add(subtitle);
+        }
+
+        return new EncodingJobInfo(TranscodingJobType.Progressive)
+        {
+            MediaSource = new MediaSourceInfo
+            {
+                Container = "mkv",
+                MediaStreams = streams,
+            },
+            VideoStream = video,
+            AudioStream = audio,
+            SubtitleStream = subtitle,
+            SubtitleDeliveryMethod = deliveryMethod ?? SubtitleDeliveryMethod.Drop,
+            BaseRequest = new VideoRequestDto(),
+            IsVideoRequest = true,
+            IsInputVideo = true,
+        };
+    }
+
+    private static EncodingHelper CreateHelper()
+    {
+        var appPaths = Mock.Of<IApplicationPaths>();
+        var mediaEncoder = new Mock<IMediaEncoder>();
+        var subtitleEncoder = new Mock<ISubtitleEncoder>();
+        var config = new Mock<IConfiguration>();
+        var configurationManager = new Mock<IConfigurationManager>();
+        var pathManager = new Mock<IPathManager>();
+
+        return new EncodingHelper(
+            appPaths,
+            mediaEncoder.Object,
+            subtitleEncoder.Object,
+            config.Object,
+            configurationManager.Object,
+            pathManager.Object);
+    }
+}