EchoHub/src/EchoHub.Tests/FileValidationHelperTests.cs

using EchoHub.Core.Services;
using Xunit;

namespace EchoHub.Tests;

public class FileValidationHelperTests
{
    [Fact]
    public void IsValidImage_JpegMagicBytes_ReturnsTrue()
    {
        byte[] jpeg = [0xFF, 0xD8, 0xFF, 0xE0, 0x00, 0x10];
        using var stream = new MemoryStream(jpeg);
        Assert.True(FileValidationHelper.IsValidImage(stream));
    }

    [Fact]
    public void IsValidImage_PngMagicBytes_ReturnsTrue()
    {
        byte[] png = [0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A];
        using var stream = new MemoryStream(png);
        Assert.True(FileValidationHelper.IsValidImage(stream));
    }

    [Fact]
    public void IsValidImage_GifMagicBytes_ReturnsTrue()
    {
        byte[] gif = [0x47, 0x49, 0x46, 0x38, 0x39, 0x61];
        using var stream = new MemoryStream(gif);
        Assert.True(FileValidationHelper.IsValidImage(stream));
    }

    [Fact]
    public void IsValidImage_WebpMagicBytes_ReturnsTrue()
    {
        byte[] webp = [0x52, 0x49, 0x46, 0x46, 0x00, 0x00, 0x00, 0x00, 0x57, 0x45, 0x42, 0x50];
        using var stream = new MemoryStream(webp);
        Assert.True(FileValidationHelper.IsValidImage(stream));
    }

    [Fact]
    public void IsValidImage_RandomBytes_ReturnsFalse()
    {
        byte[] random = [0x00, 0x01, 0x02, 0x03, 0x04, 0x05];
        using var stream = new MemoryStream(random);
        Assert.False(FileValidationHelper.IsValidImage(stream));
    }

    [Fact]
    public void IsValidImage_ResetsStreamPosition()
    {
        byte[] jpeg = [0xFF, 0xD8, 0xFF, 0xE0, 0x00, 0x10];
        using var stream = new MemoryStream(jpeg);
        FileValidationHelper.IsValidImage(stream);
        Assert.Equal(0, stream.Position);
    }

    // ── IsAudioFile tests ─────────────────────────────────────────────

    [Theory]
    [InlineData("song.mp3")]
    [InlineData("track.wav")]
    [InlineData("audio.ogg")]
    [InlineData("music.flac")]
    [InlineData("clip.aac")]
    [InlineData("podcast.m4a")]
    [InlineData("old.wma")]
    public void IsAudioFile_SupportedExtensions_ReturnsTrue(string fileName)
    {
        Assert.True(FileValidationHelper.IsAudioFile(fileName));
    }

    [Theory]
    [InlineData("song.MP3")]
    [InlineData("track.Wav")]
    [InlineData("audio.OGG")]
    [InlineData("music.FLAC")]
    public void IsAudioFile_CaseInsensitive_ReturnsTrue(string fileName)
    {
        Assert.True(FileValidationHelper.IsAudioFile(fileName));
    }

    [Theory]
    [InlineData("document.txt")]
    [InlineData("report.pdf")]
    [InlineData("app.exe")]
    [InlineData("photo.jpg")]
    [InlineData("image.png")]
    public void IsAudioFile_NonAudioExtension_ReturnsFalse(string fileName)
    {
        Assert.False(FileValidationHelper.IsAudioFile(fileName));
    }

    [Theory]
    [InlineData("")]
    [InlineData("noextension")]
    public void IsAudioFile_EmptyOrNoExtension_ReturnsFalse(string fileName)
    {
        Assert.False(FileValidationHelper.IsAudioFile(fileName));
    }
}