PowderCoatingLogix/tests/PowderCoating.UnitTests/FileServiceTests.cs

using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Moq;
using PowderCoating.Application.Services;

namespace PowderCoating.UnitTests;

public class FileServiceTests
{
    [Fact]
    public async Task DeleteFileAsync_ReturnsError_WhenPathEscapesUploadsRoot()
    {
        using var harness = new FileServiceHarness();

        var result = await harness.Service.DeleteFileAsync("uploads/../secrets.txt");

        Assert.False(result.Success);
        Assert.Equal("Invalid file path.", result.ErrorMessage);
    }

    [Fact]
    public async Task GetFileAsync_ReturnsError_WhenPathEscapesUploadsRoot()
    {
        using var harness = new FileServiceHarness();

        var result = await harness.Service.GetFileAsync("uploads/../../appsettings.json");

        Assert.False(result.Success);
        Assert.Equal("Invalid file path.", result.ErrorMessage);
        Assert.Empty(result.FileContent);
    }

    [Fact]
    public async Task SaveFileAsync_ReturnsError_WhenSubfolderEscapesUploadsRoot()
    {
        using var harness = new FileServiceHarness();

        var result = await harness.Service.SaveFileAsync(
            CreateFormFile("manual.pdf"),
            "../outside",
            new[] { ".pdf" },
            1024 * 1024);

        Assert.False(result.Success);
        Assert.Equal("Invalid upload subfolder.", result.ErrorMessage);
    }

    [Fact]
    public async Task GetFileAsync_ReturnsFile_WhenPathIsUnderUploadsRoot()
    {
        using var harness = new FileServiceHarness();
        var uploadsPath = Path.Combine(harness.WebRootPath, "uploads", "equipment-manuals");
        Directory.CreateDirectory(uploadsPath);

        var fullPath = Path.Combine(uploadsPath, "manual.pdf");
        await File.WriteAllBytesAsync(fullPath, [1, 2, 3]);

        var result = await harness.Service.GetFileAsync("uploads/equipment-manuals/manual.pdf");

        Assert.True(result.Success);
        Assert.Equal("application/pdf", result.ContentType);
        Assert.Equal(new byte[] { 1, 2, 3 }, result.FileContent);
    }

    private static IFormFile CreateFormFile(string fileName)
    {
        var bytes = new byte[] { 1, 2, 3, 4 };
        var stream = new MemoryStream(bytes);
        return new FormFile(stream, 0, bytes.Length, "file", fileName);
    }

    private sealed class FileServiceHarness : IDisposable
    {
        public FileServiceHarness()
        {
            WebRootPath = Path.Combine(Path.GetTempPath(), "powdercoating-fileservice-tests", Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(WebRootPath);

            var environment = Mock.Of<IWebHostEnvironment>(x => x.WebRootPath == WebRootPath);
            Service = new FileService(environment, Mock.Of<ILogger<FileService>>());
        }

        public string WebRootPath { get; }
        public FileService Service { get; }

        public void Dispose()
        {
            if (Directory.Exists(WebRootPath))
            {
                Directory.Delete(WebRootPath, recursive: true);
            }
        }
    }
}