using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.Uns;

namespace ZB.MOM.WW.OtOpcUa.AdminUI.Tests.Uns;

/// <summary>
/// Verifies the load-for-edit projections on <see cref="UnsTreeService"/> that prefill the
/// Area/Line edit modals and carry the concurrency token back for last-write-wins saves.
/// </summary>
[Trait("Category", "Unit")]
public sealed class UnsTreeServiceLoadEditTests
{
    private static (UnsTreeService Service, string DbName) Seeded()
    {
        var dbName = $"uns-loadedit-{Guid.NewGuid():N}";
        UnsTreeTestDb.SeedNamed(dbName);
        return (new UnsTreeService(UnsTreeTestDb.Factory(dbName)), dbName);
    }

    /// <summary>Loading a seeded area maps its fields, owning cluster, and a non-empty RowVersion.</summary>
    [Fact]
    public async Task LoadArea_returns_dto()
    {
        var (service, _) = Seeded();

        var dto = await service.LoadAreaAsync("AREA-1");

        dto.ShouldNotBeNull();
        dto.UnsAreaId.ShouldBe("AREA-1");
        dto.Name.ShouldBe("assembly");
        dto.ClusterId.ShouldBe(UnsTreeTestDb.PopulatedClusterId);
        dto.RowVersion.ShouldNotBeNull();
    }

    /// <summary>Loading a missing area returns null.</summary>
    [Fact]
    public async Task LoadArea_missing_returns_null()
    {
        var (service, _) = Seeded();

        (await service.LoadAreaAsync("NOPE")).ShouldBeNull();
    }

    /// <summary>Loading a seeded line maps its fields, parent area, and a non-empty RowVersion.</summary>
    [Fact]
    public async Task LoadLine_returns_dto()
    {
        var (service, _) = Seeded();

        var dto = await service.LoadLineAsync("LINE-1");

        dto.ShouldNotBeNull();
        dto.UnsLineId.ShouldBe("LINE-1");
        dto.UnsAreaId.ShouldBe("AREA-1");
        dto.Name.ShouldBe("line-a");
        dto.RowVersion.ShouldNotBeNull();
    }

    /// <summary>Loading a missing line returns null.</summary>
    [Fact]
    public async Task LoadLine_missing_returns_null()
    {
        var (service, _) = Seeded();

        (await service.LoadLineAsync("NOPE")).ShouldBeNull();
    }
}