using System.Text.Json.Nodes;
using FluentAssertions;
using Microsoft.Extensions.Logging.Abstractions;
using StellaOps.Findings.Ledger.Domain;
using StellaOps.Findings.Ledger.Hashing;
using StellaOps.Findings.Ledger.Infrastructure.Policy;
using StellaOps.Findings.Ledger.Services;
using Xunit;

namespace StellaOps.Findings.Ledger.Tests;

public sealed class InlinePolicyEvaluationServiceTests
{
    private readonly InlinePolicyEvaluationService _service = new(NullLogger<InlinePolicyEvaluationService>.Instance);

    [Fact]
    public async Task EvaluateAsync_UsesPayloadValues_WhenPresent()
    {
        var payload = new JsonObject
        {
            ["status"] = "triaged",
            ["severity"] = 5.2,
            ["labels"] = new JsonObject
            {
                ["kev"] = true,
                ["runtime"] = "exposed"
            },
            ["labelsRemove"] = new JsonArray("deprecated"),
            ["explainRef"] = "explain://tenant/findings/1",
            ["rationaleRefs"] = new JsonArray("explain://tenant/findings/1", "policy://tenant/pol/version/rationale")
        };

        var existingProjection = new FindingProjection(
            "tenant",
            "finding",
            "policy-sha",
            "affected",
            7.1m,
            new JsonObject { ["deprecated"] = "true" },
            Guid.NewGuid(),
            null,
            new JsonArray("explain://existing"),
            DateTimeOffset.UtcNow,
            string.Empty);

        var record = CreateRecord(payload);

        var result = await _service.EvaluateAsync(record, existingProjection, default);

        result.Status.Should().Be("triaged");
        result.Severity.Should().Be(5.2m);
        result.Labels["kev"]!.GetValue<bool>().Should().BeTrue();
        result.Labels.ContainsKey("deprecated").Should().BeFalse();
        result.Labels["runtime"]!.GetValue<string>().Should().Be("exposed");
        result.ExplainRef.Should().Be("explain://tenant/findings/1");
        result.Rationale.Should().HaveCount(2);
        result.Rationale[0]!.GetValue<string>().Should().Be("explain://tenant/findings/1");
        result.Rationale[1]!.GetValue<string>().Should().Be("policy://tenant/pol/version/rationale");
    }

    [Fact]
    public async Task EvaluateAsync_FallsBack_WhenEventMissing()
    {
        var existingRationale = new JsonArray("explain://existing/rationale");
        var existingProjection = new FindingProjection(
            "tenant",
            "finding",
            "policy-sha",
            "accepted_risk",
            3.4m,
            new JsonObject { ["runtime"] = "contained" },
            Guid.NewGuid(),
            "explain://existing",
            existingRationale,
            DateTimeOffset.UtcNow,
            string.Empty);

        var record = new LedgerEventRecord(
            "tenant",
            Guid.NewGuid(),
            1,
            Guid.NewGuid(),
            "finding.status_changed",
            "policy-sha",
            "finding",
            "artifact",
            null,
            "user:alice",
            "operator",
            DateTimeOffset.UtcNow,
            DateTimeOffset.UtcNow,
            new JsonObject(),
            "hash",
            "prev",
            "leaf",
            "{}"
        );

        var result = await _service.EvaluateAsync(record, existingProjection, default);

        result.Status.Should().Be("accepted_risk");
        result.Severity.Should().Be(3.4m);
        result.Labels["runtime"]!.GetValue<string>().Should().Be("contained");
        result.ExplainRef.Should().Be("explain://existing");
        result.Rationale.Should().HaveCount(1);
        result.Rationale[0]!.GetValue<string>().Should().Be("explain://existing/rationale");
    }

    private static LedgerEventRecord CreateRecord(JsonObject payload)
    {
        var eventObject = new JsonObject
        {
            ["id"] = Guid.NewGuid().ToString(),
            ["type"] = "finding.status_changed",
            ["tenant"] = "tenant",
            ["chainId"] = Guid.NewGuid().ToString(),
            ["sequence"] = 10,
            ["policyVersion"] = "policy-sha",
            ["artifactId"] = "artifact",
            ["finding"] = new JsonObject
            {
                ["id"] = "finding",
                ["artifactId"] = "artifact",
                ["vulnId"] = "CVE-0000-0001"
            },
            ["actor"] = new JsonObject
            {
                ["id"] = "user:alice",
                ["type"] = "operator"
            },
            ["occurredAt"] = "2025-11-04T12:00:00.000Z",
            ["recordedAt"] = "2025-11-04T12:00:01.000Z",
            ["payload"] = payload.DeepClone()
        };

        var envelope = new JsonObject
        {
            ["event"] = eventObject
        };

        var canonical = LedgerCanonicalJsonSerializer.Canonicalize(envelope);
        var canonicalJson = LedgerCanonicalJsonSerializer.Serialize(canonical);

        return new LedgerEventRecord(
            "tenant",
            Guid.Parse(eventObject["chainId"]!.GetValue<string>()),
            10,
            Guid.Parse(eventObject["id"]!.GetValue<string>()),
            eventObject["type"]!.GetValue<string>(),
            eventObject["policyVersion"]!.GetValue<string>(),
            eventObject["finding"]!["id"]!.GetValue<string>(),
            eventObject["artifactId"]!.GetValue<string>(),
            null,
            eventObject["actor"]!["id"]!.GetValue<string>(),
            eventObject["actor"]!["type"]!.GetValue<string>(),
            DateTimeOffset.Parse(eventObject["occurredAt"]!.GetValue<string>()),
            DateTimeOffset.Parse(eventObject["recordedAt"]!.GetValue<string>()),
            canonical,
            "hash",
            "prev",
            "leaf",
            canonicalJson);
    }
}