releases/tests/Paca.Tests/Core/MediaMuxerAndMetadataExtremeRedTests.cs

using System;
using System.Collections.Generic;
using Paca.Core;
using Xunit;

namespace Paca.Tests.Core;

public class MediaMuxerAndMetadataExtremeRedTests
{
    private const string SampleIn1 = "C:\\Media\\video.mp4";
    private const string SampleAudio = "C:\\Media\\audio.m4a";
    private const string SampleOut = "C:\\Media\\output.mp4";

    // ==========================================
    // 1. MediaMetadataTagWriter
    // ==========================================

    [Fact]
    public void MediaMetadataTagWriter_BuildFfmpegArgs_NullTag_ThrowsArgumentNullException()
    {
        Assert.Throws<ArgumentNullException>(() =>
            MediaMetadataTagWriter.BuildFfmpegArgs(null!, SampleIn1, SampleOut));
    }

    [Theory]
    [InlineData(null, SampleOut)]
    [InlineData(SampleIn1, null)]
    [InlineData("", SampleOut)]
    [InlineData(SampleIn1, "   ")]
    public void MediaMetadataTagWriter_BuildFfmpegArgs_NullOrWhitespacePaths_ThrowsArgumentException(string? inPath, string? outPath)
    {
        var tag = new MediaMetadataTag { Title = "Song" };
        Assert.Throws<ArgumentException>(() =>
            MediaMetadataTagWriter.BuildFfmpegArgs(tag, inPath!, outPath!));
    }

    [Fact]
    public void MediaMetadataTagWriter_BuildFfmpegArgs_SameInputAndOutput_ThrowsInvalidOperationException()
    {
        var tag = new MediaMetadataTag { Title = "Song" };
        Assert.Throws<InvalidOperationException>(() =>
            MediaMetadataTagWriter.BuildFfmpegArgs(tag, SampleIn1, SampleIn1));
    }

    [Fact]
    public void MediaMetadataTagWriter_BuildFfmpegArgs_PathsWithQuotes_EscapedOrStripped()
    {
        var tag = new MediaMetadataTag { Title = "Song" };
        string maliciousIn = "C:\\Media\\in\"put.mp4";
        string maliciousOut = "C:\\Media\\out\"put.mp4";

        var cmd = MediaMetadataTagWriter.BuildFfmpegArgs(tag, maliciousIn, maliciousOut);
        Assert.NotNull(cmd);
        Assert.DoesNotContain("in\"put", cmd);
        Assert.DoesNotContain("out\"put", cmd);
    }

    // ==========================================
    // 2. MultiTrackMediaMuxer
    // ==========================================

    [Fact]
    public void MultiTrackMediaMuxer_BuildMuxCommandLine_NullJob_ThrowsArgumentNullException()
    {
        Assert.Throws<ArgumentNullException>(() =>
            MultiTrackMediaMuxer.BuildMuxCommandLine(null!));
    }

    [Theory]
    [InlineData(null)]
    [InlineData("")]
    [InlineData("   ")]
    public void MultiTrackMediaMuxer_BuildMuxCommandLine_NullOrWhitespaceOutputPath_ThrowsArgumentException(string? badOut)
    {
        var job = new MuxJobSpecification
        {
            VideoTrack = new TrackSpec(SampleIn1),
            OutputPath = badOut!
        };
        Assert.Throws<ArgumentException>(() =>
            MultiTrackMediaMuxer.BuildMuxCommandLine(job));
    }

    [Fact]
    public void MultiTrackMediaMuxer_BuildMuxCommandLine_NoTracks_ThrowsInvalidOperationException()
    {
        var job = new MuxJobSpecification
        {
            OutputPath = SampleOut
        };
        Assert.Throws<InvalidOperationException>(() =>
            MultiTrackMediaMuxer.BuildMuxCommandLine(job));
    }

    [Fact]
    public void MultiTrackMediaMuxer_BuildMuxCommandLine_OutputPathMatchesAnyInput_ThrowsInvalidOperationException()
    {
        var job = new MuxJobSpecification
        {
            VideoTrack = new TrackSpec(SampleIn1),
            AudioTracks = new List<TrackSpec> { new(SampleAudio) },
            OutputPath = SampleAudio // Overwriting audio source!
        };
        Assert.Throws<InvalidOperationException>(() =>
            MultiTrackMediaMuxer.BuildMuxCommandLine(job));
    }

    [Fact]
    public void MultiTrackMediaMuxer_BuildMuxCommandLine_TrackTitleWithQuotes_EscapedSafely()
    {
        var job = new MuxJobSpecification
        {
            VideoTrack = new TrackSpec(SampleIn1),
            AudioTracks = new List<TrackSpec> { new(SampleAudio, Title: "Director's \"Commentary\"") },
            OutputPath = SampleOut
        };
        var cmd = MultiTrackMediaMuxer.BuildMuxCommandLine(job);
        Assert.NotNull(cmd);
        Assert.DoesNotContain("title=\"Director's \"Commentary\"\"", cmd);
    }

    // ==========================================
    // 3. VideoTonemapEnhancer
    // ==========================================

    [Theory]
    [InlineData(null, SampleOut)]
    [InlineData(SampleIn1, null)]
    public void VideoTonemapEnhancer_BuildFfmpegArgs_NullOrWhitespacePaths_ThrowsArgumentException(string? inPath, string? outPath)
    {
        Assert.Throws<ArgumentException>(() =>
            VideoTonemapEnhancer.BuildFfmpegArgs(inPath!, outPath!, TonemapAlgorithm.Hable, ColorGradePreset.None));
    }

    [Fact]
    public void VideoTonemapEnhancer_BuildFfmpegArgs_SameInputAndOutput_ThrowsInvalidOperationException()
    {
        Assert.Throws<InvalidOperationException>(() =>
            VideoTonemapEnhancer.BuildFfmpegArgs(SampleIn1, SampleIn1, TonemapAlgorithm.Hable, ColorGradePreset.None));
    }

    [Fact]
    public void VideoTonemapEnhancer_BuildFfmpegArgs_PathsWithQuotes_EscapedOrStripped()
    {
        string maliciousIn = "C:\\Media\\in\"put.mp4";
        string maliciousOut = "C:\\Media\\out\"put.mp4";

        var cmd = VideoTonemapEnhancer.BuildFfmpegArgs(maliciousIn, maliciousOut, TonemapAlgorithm.Hable, ColorGradePreset.None);
        Assert.NotNull(cmd);
        Assert.DoesNotContain("in\"put", cmd);
        Assert.DoesNotContain("out\"put", cmd);
    }

    [Fact]
    public void VideoTonemapEnhancer_BuildFfmpegArgs_InvalidEncoderOrCrf_ClampedSafely()
    {
        var cmd = VideoTonemapEnhancer.BuildFfmpegArgs(
            SampleIn1, SampleOut, TonemapAlgorithm.Hable, ColorGradePreset.None,
            crf: 999, videoEncoder: "libx264; echo pwned");
        Assert.NotNull(cmd);
        Assert.Contains("-crf 51", cmd);
        Assert.DoesNotContain(";", cmd);
    }
}