using NSubstitute;
using PnvPanel.Application.Admin.Media;
using PnvPanel.Application.Common.Interfaces;
using PnvPanel.Application.Media;
using PnvPanel.Application.Tests.TestSupport;
using Xunit;

namespace PnvPanel.Application.Tests.Media;

public class UploadMediaImageCommandHandlerTests
{
    private readonly IFileStorage _fileStorage = Substitute.For<IFileStorage>();

    private static MediaImageUpload Upload(
        string contentType = "image/png",
        long sizeBytes = 1024,
        string fileName = "screenshot.png"
    ) => new(new MemoryStream([1, 2, 3]), fileName, contentType, sizeBytes);

    [Fact]
    public async Task Handle_WithValidImage_SavesFileAndRow()
    {
        using var dbContext = InMemoryDbContextFactory.Create();
        var adminId = Guid.NewGuid();
        _fileStorage
            .SaveAsync(Arg.Any<Stream>(), Arg.Any<CancellationToken>())
            .Returns("stored-name");

        var handler = new UploadMediaImageCommandHandler(
            dbContext,
            _fileStorage,
            FakeCurrentUser.Authenticated(adminId, "admin")
        );

        var result = await handler.Handle(
            new UploadMediaImageCommand(Upload()),
            CancellationToken.None
        );
        await dbContext.SaveChangesAsync(CancellationToken.None);

        Assert.True(result.IsSuccess);
        Assert.Equal("screenshot.png", result.Value.FileName);
        var image = Assert.Single(dbContext.MediaImages);
        Assert.Equal("stored-name", image.StoredFileName);
        Assert.Equal(adminId, image.UploadedBy);
    }

    [Fact]
    public async Task Handle_WithUnsupportedContentType_ReturnsValidationErrorWithoutSaving()
    {
        using var dbContext = InMemoryDbContextFactory.Create();

        var handler = new UploadMediaImageCommandHandler(
            dbContext,
            _fileStorage,
            FakeCurrentUser.Authenticated(Guid.NewGuid())
        );

        var result = await handler.Handle(
            new UploadMediaImageCommand(Upload(contentType: "image/svg+xml", fileName: "x.svg")),
            CancellationToken.None
        );

        Assert.False(result.IsSuccess);
        Assert.Equal(MediaErrors.UnsupportedImageType, result.Error);
        Assert.Empty(dbContext.MediaImages);
        await _fileStorage
            .DidNotReceive()
            .SaveAsync(Arg.Any<Stream>(), Arg.Any<CancellationToken>());
    }

    /// <summary>Лимит продублирован из MediaImageValidation — она internal (см. Application).</summary>
    private const long MaxSizeBytes = 5 * 1024 * 1024;

    [Fact]
    public async Task Handle_WithTooLargeImage_ReturnsValidationError()
    {
        using var dbContext = InMemoryDbContextFactory.Create();

        var handler = new UploadMediaImageCommandHandler(
            dbContext,
            _fileStorage,
            FakeCurrentUser.Authenticated(Guid.NewGuid())
        );

        var result = await handler.Handle(
            new UploadMediaImageCommand(Upload(sizeBytes: MaxSizeBytes + 1)),
            CancellationToken.None
        );

        Assert.False(result.IsSuccess);
        Assert.Equal(MediaErrors.ImageTooLarge, result.Error);
        Assert.Empty(dbContext.MediaImages);
    }
}