// SPDX-License-Identifier: AGPL-3.0-or-later
// Copyright (c) StellaOps

using System.Collections.Immutable;
using FluentAssertions;
using StellaOps.Scanner.Emit.Lineage;

using StellaOps.TestKit;
namespace StellaOps.Scanner.Emit.Lineage.Tests;

public class SbomLineageTests
{
    #region SbomId Tests

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomId_New_CreatesUniqueId()
    {
        var id1 = SbomId.New();
        var id2 = SbomId.New();

        id1.Should().NotBe(id2);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomId_Parse_RoundTrips()
    {
        var original = SbomId.New();
        var parsed = SbomId.Parse(original.ToString());

        parsed.Should().Be(original);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomId_ToString_ReturnsGuidString()
    {
        var id = SbomId.New();
        var str = id.ToString();

        Guid.TryParse(str, out _).Should().BeTrue();
    }

    #endregion

    #region SbomLineage Model Tests

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomLineage_RequiredProperties_MustBeSet()
    {
        var lineage = new SbomLineage
        {
            Id = SbomId.New(),
            ImageDigest = "sha256:abc123",
            ContentHash = "sha256:def456",
            CreatedAt = DateTimeOffset.UtcNow
        };

        lineage.Id.Should().NotBe(default(SbomId));
        lineage.ImageDigest.Should().Be("sha256:abc123");
        lineage.ContentHash.Should().Be("sha256:def456");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomLineage_WithParent_TracksLineage()
    {
        var parentId = SbomId.New();
        var childId = SbomId.New();

        var child = new SbomLineage
        {
            Id = childId,
            ParentId = parentId,
            ImageDigest = "sha256:child",
            ContentHash = "sha256:childhash",
            CreatedAt = DateTimeOffset.UtcNow,
            Ancestors = [parentId]
        };

        child.ParentId.Should().Be(parentId);
        child.Ancestors.Should().Contain(parentId);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomLineage_WithDiffPointer_TracksChanges()
    {
        var diff = new SbomDiffPointer
        {
            ComponentsAdded = 5,
            ComponentsRemoved = 2,
            ComponentsModified = 3,
            DiffHash = "sha256:diffhash"
        };

        var lineage = new SbomLineage
        {
            Id = SbomId.New(),
            ParentId = SbomId.New(),
            ImageDigest = "sha256:image",
            ContentHash = "sha256:content",
            CreatedAt = DateTimeOffset.UtcNow,
            DiffFromParent = diff
        };

        lineage.DiffFromParent.Should().NotBeNull();
        lineage.DiffFromParent!.TotalChanges.Should().Be(10);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomLineage_RootLineage_HasNoParent()
    {
        var root = new SbomLineage
        {
            Id = SbomId.New(),
            ImageDigest = "sha256:root",
            ContentHash = "sha256:roothash",
            CreatedAt = DateTimeOffset.UtcNow
        };

        root.ParentId.Should().BeNull();
        root.Ancestors.Should().BeEmpty();
        root.DiffFromParent.Should().BeNull();
    }

    #endregion

    #region SbomDiffPointer Tests

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomDiffPointer_TotalChanges_SumsAllCategories()
    {
        var pointer = new SbomDiffPointer
        {
            ComponentsAdded = 10,
            ComponentsRemoved = 5,
            ComponentsModified = 8,
            DiffHash = "sha256:hash"
        };

        pointer.TotalChanges.Should().Be(23);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public void SbomDiffPointer_EmptyDiff_HasZeroChanges()
    {
        var pointer = new SbomDiffPointer
        {
            ComponentsAdded = 0,
            ComponentsRemoved = 0,
            ComponentsModified = 0,
            DiffHash = "sha256:empty"
        };

        pointer.TotalChanges.Should().Be(0);
    }

    #endregion
}