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

using System.Collections.Immutable;
using StellaOps.Attestor.ProofChain.Predicates;
using StellaOps.Scanner.SmartDiff.Attestation;
using StellaOps.Scanner.SmartDiff.Detection;
using Xunit;

namespace StellaOps.Scanner.SmartDiffTests;

public sealed class DeltaVerdictBuilderTests
{
    [Fact]
    public void BuildStatement_BuildsPredicateAndSubjects()
    {
        var changes = new[]
        {
            new MaterialRiskChangeResult(
                FindingKey: new FindingKey("CVE-2025-0001", "pkg:npm/a@1.0.0"),
                HasMaterialChange: true,
                Changes: ImmutableArray.Create(new DetectedChange(
                    Rule: DetectionRule.R1_ReachabilityFlip,
                    ChangeType: MaterialChangeType.ReachabilityFlip,
                    Direction: RiskDirection.Increased,
                    Reason: "reachability_flip",
                    PreviousValue: "false",
                    CurrentValue: "true",
                    Weight: 1.0)),
                PriorityScore: 100,
                PreviousStateHash: "sha256:prev",
                CurrentStateHash: "sha256:curr"),
            new MaterialRiskChangeResult(
                FindingKey: new FindingKey("CVE-2025-0002", "pkg:npm/b@2.0.0"),
                HasMaterialChange: true,
                Changes: ImmutableArray.Create(new DetectedChange(
                    Rule: DetectionRule.R2_VexFlip,
                    ChangeType: MaterialChangeType.VexFlip,
                    Direction: RiskDirection.Decreased,
                    Reason: "vex_flip",
                    PreviousValue: "affected",
                    CurrentValue: "not_affected",
                    Weight: 0.7)),
                PriorityScore: 50,
                PreviousStateHash: "sha256:prev2",
                CurrentStateHash: "sha256:curr2")
        };

        var request = new DeltaVerdictBuildRequest
        {
            BeforeRevisionId = "rev-before",
            AfterRevisionId = "rev-after",
            BeforeImageDigest = "sha256:before",
            AfterImageDigest = "sha256:after",
            Changes = changes,
            ComparedAt = new DateTimeOffset(2025, 12, 22, 0, 0, 0, TimeSpan.Zero),
            BeforeProofSpine = new AttestationReference { Digest = "sha256:spine-before" },
            AfterProofSpine = new AttestationReference { Digest = "sha256:spine-after" }
        };

        var builder = new DeltaVerdictBuilder();
        var statement = builder.BuildStatement(request);

        Assert.Equal(2, statement.Subject.Count);
        Assert.Equal("delta-verdict.stella/v1", statement.PredicateType);
        Assert.True(statement.Predicate.HasMaterialChange);
        Assert.Equal(150, statement.Predicate.PriorityScore);
        Assert.Equal("rev-before", statement.Predicate.BeforeRevisionId);
        Assert.Equal("rev-after", statement.Predicate.AfterRevisionId);
        Assert.Equal(2, statement.Predicate.Changes.Length);
        Assert.Equal("R1", statement.Predicate.Changes[0].Rule);
        Assert.Equal("increased", statement.Predicate.Changes[0].Direction);
    }
}