using System.Collections.Immutable;
using FluentAssertions;
using Microsoft.Extensions.Logging.Abstractions;
using Microsoft.Extensions.Options;
using StellaOps.Determinism;
using StellaOps.Policy.Exceptions.Models;
using StellaOps.Policy.Exceptions.Repositories;
using StellaOps.Policy.Persistence.Postgres;
using StellaOps.Policy.Persistence.Postgres.Repositories;
using Xunit;

using StellaOps.TestKit;
namespace StellaOps.Policy.Persistence.Tests;

/// <summary>
/// Integration tests for PostgresExceptionObjectRepository.
/// Tests the new auditable exception objects against PostgreSQL.
/// </summary>
[Collection(PolicyPostgresCollection.Name)]
public sealed class ExceptionObjectRepositoryTests : IAsyncLifetime
{
    private readonly PolicyPostgresFixture _fixture;
    private readonly PostgresExceptionObjectRepository _repository;

    public ExceptionObjectRepositoryTests(PolicyPostgresFixture fixture)
    {
        _fixture = fixture;

        var options = fixture.Fixture.CreateOptions();
        options.SchemaName = fixture.SchemaName;
        var dataSource = new PolicyDataSource(Options.Create(options), NullLogger<PolicyDataSource>.Instance);
        _repository = new PostgresExceptionObjectRepository(dataSource, NullLogger<PostgresExceptionObjectRepository>.Instance, TimeProvider.System, SystemGuidProvider.Instance);
    }

    public ValueTask InitializeAsync() => new(_fixture.TruncateAllTablesAsync());
    public ValueTask DisposeAsync() => ValueTask.CompletedTask;

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task CreateAsync_ShouldPersistExceptionAndCreateEvent()
    {
        // Arrange
        var exception = CreateException("EXC-CREATE-001");

        // Act
        var created = await _repository.CreateAsync(exception, "test-actor", "127.0.0.1");

        // Assert
        created.Should().NotBeNull();
        created.ExceptionId.Should().Be("EXC-CREATE-001");
        created.Version.Should().Be(1);

        // Verify event was created
        var history = await _repository.GetHistoryAsync("EXC-CREATE-001");
        history.Events.Should().HaveCount(1);
        history.Events[0].EventType.Should().Be(ExceptionEventType.Created);
        history.Events[0].ActorId.Should().Be("test-actor");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByIdAsync_WhenExists_ShouldReturnException()
    {
        // Arrange
        var exception = CreateException("EXC-GETBYID-001");
        await _repository.CreateAsync(exception, "test-actor");

        // Act
        var fetched = await _repository.GetByIdAsync("EXC-GETBYID-001");

        // Assert
        fetched.Should().NotBeNull();
        fetched!.ExceptionId.Should().Be("EXC-GETBYID-001");
        fetched.Status.Should().Be(ExceptionStatus.Proposed);
        fetched.Type.Should().Be(ExceptionType.Vulnerability);
        fetched.Scope.VulnerabilityId.Should().Be("CVE-2024-12345");
        fetched.OwnerId.Should().Be("owner@example.com");
        fetched.ReasonCode.Should().Be(ExceptionReason.AcceptedRisk);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByIdAsync_WhenNotExists_ShouldReturnNull()
    {
        // Act
        var fetched = await _repository.GetByIdAsync("EXC-NONEXISTENT");

        // Assert
        fetched.Should().BeNull();
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task UpdateAsync_ShouldIncrementVersionAndCreateEvent()
    {
        // Arrange
        var exception = CreateException("EXC-UPDATE-001");
        await _repository.CreateAsync(exception, "creator");

        var updated = exception with
        {
            Version = 2,
            Status = ExceptionStatus.Approved,
            ApprovedAt = DateTimeOffset.UtcNow,
            ApproverIds = ["approver@example.com"],
            UpdatedAt = DateTimeOffset.UtcNow
        };

        // Act
        var result = await _repository.UpdateAsync(updated, ExceptionEventType.Approved, "approver@example.com", "Approved by security team");

        // Assert
        result.Version.Should().Be(2);
        result.Status.Should().Be(ExceptionStatus.Approved);

        var fetched = await _repository.GetByIdAsync("EXC-UPDATE-001");
        fetched!.Version.Should().Be(2);
        fetched.Status.Should().Be(ExceptionStatus.Approved);

        // Verify events
        var history = await _repository.GetHistoryAsync("EXC-UPDATE-001");
        history.Events.Should().HaveCount(2);
        history.Events[1].EventType.Should().Be(ExceptionEventType.Approved);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task UpdateAsync_WithConcurrencyConflict_ShouldThrow()
    {
        // Arrange
        var exception = CreateException("EXC-CONCURRENCY-001");
        await _repository.CreateAsync(exception, "creator");

        // Simulate stale version
        var staleUpdate = exception with
        {
            Version = 5, // Wrong version - should be 2
            UpdatedAt = DateTimeOffset.UtcNow
        };

        // Act & Assert
        await Assert.ThrowsAsync<ConcurrencyException>(() =>
            _repository.UpdateAsync(staleUpdate, ExceptionEventType.Updated, "updater"));
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByFilterAsync_ShouldFilterByStatus()
    {
        // Arrange
        var proposed = CreateException("EXC-FILTER-001", status: ExceptionStatus.Proposed);
        var active = CreateException("EXC-FILTER-002", status: ExceptionStatus.Active);
        var revoked = CreateException("EXC-FILTER-003", status: ExceptionStatus.Revoked);

        await _repository.CreateAsync(proposed, "actor");
        await _repository.CreateAsync(active, "actor");
        await _repository.CreateAsync(revoked, "actor");

        // Act
        var filter = new ExceptionFilter { Status = ExceptionStatus.Proposed };
        var results = await _repository.GetByFilterAsync(filter);

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-FILTER-001");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByFilterAsync_ShouldFilterByType()
    {
        // Arrange
        var vuln = CreateException("EXC-TYPE-001", type: ExceptionType.Vulnerability);
        var policy = CreateException("EXC-TYPE-002", type: ExceptionType.Policy);

        await _repository.CreateAsync(vuln, "actor");
        await _repository.CreateAsync(policy, "actor");

        // Act
        var filter = new ExceptionFilter { Type = ExceptionType.Policy };
        var results = await _repository.GetByFilterAsync(filter);

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-TYPE-002");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByFilterAsync_ShouldFilterByVulnerabilityId()
    {
        // Arrange
        var exc1 = CreateException("EXC-VID-001", vulnerabilityId: "CVE-2024-11111");
        var exc2 = CreateException("EXC-VID-002", vulnerabilityId: "CVE-2024-22222");

        await _repository.CreateAsync(exc1, "actor");
        await _repository.CreateAsync(exc2, "actor");

        // Act
        var filter = new ExceptionFilter { VulnerabilityId = "CVE-2024-11111" };
        var results = await _repository.GetByFilterAsync(filter);

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-VID-001");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetByFilterAsync_ShouldSupportPagination()
    {
        // Arrange
        for (int i = 0; i < 5; i++)
        {
            await _repository.CreateAsync(CreateException($"EXC-PAGE-{i:D3}"), "actor");
        }

        // Act
        var filter = new ExceptionFilter { Limit = 2, Offset = 2 };
        var results = await _repository.GetByFilterAsync(filter);

        // Assert
        results.Should().HaveCount(2);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetActiveByScopeAsync_ShouldMatchVulnerabilityId()
    {
        // Arrange
        var exception = CreateException("EXC-SCOPE-001", vulnerabilityId: "CVE-2024-99999", status: ExceptionStatus.Active);
        await _repository.CreateAsync(exception, "actor");

        var scope = new ExceptionScope { VulnerabilityId = "CVE-2024-99999" };

        // Act
        var results = await _repository.GetActiveByScopeAsync(scope);

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-SCOPE-001");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetActiveByScopeAsync_ShouldExcludeInactiveExceptions()
    {
        // Arrange
        var proposed = CreateException("EXC-INACTIVE-001", vulnerabilityId: "CVE-2024-88888", status: ExceptionStatus.Proposed);
        var revoked = CreateException("EXC-INACTIVE-002", vulnerabilityId: "CVE-2024-88888", status: ExceptionStatus.Revoked);

        await _repository.CreateAsync(proposed, "actor");
        await _repository.CreateAsync(revoked, "actor");

        var scope = new ExceptionScope { VulnerabilityId = "CVE-2024-88888" };

        // Act
        var results = await _repository.GetActiveByScopeAsync(scope);

        // Assert
        results.Should().BeEmpty();
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetExpiringAsync_ShouldReturnExceptionsExpiringSoon()
    {
        // Arrange
        var expiringSoon = CreateException("EXC-EXPIRING-001", 
            status: ExceptionStatus.Active, 
            expiresAt: DateTimeOffset.UtcNow.AddDays(3));
        var expiringLater = CreateException("EXC-EXPIRING-002", 
            status: ExceptionStatus.Active, 
            expiresAt: DateTimeOffset.UtcNow.AddDays(30));

        await _repository.CreateAsync(expiringSoon, "actor");
        await _repository.CreateAsync(expiringLater, "actor");

        // Act
        var results = await _repository.GetExpiringAsync(TimeSpan.FromDays(7));

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-EXPIRING-001");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetExpiredActiveAsync_ShouldReturnExpiredButActiveExceptions()
    {
        // Arrange - Create with past expiry
        var expired = CreateException("EXC-EXPIRED-001", 
            status: ExceptionStatus.Active, 
            expiresAt: DateTimeOffset.UtcNow.AddDays(-1));

        await _repository.CreateAsync(expired, "actor");

        // Act
        var results = await _repository.GetExpiredActiveAsync();

        // Assert
        results.Should().ContainSingle();
        results[0].ExceptionId.Should().Be("EXC-EXPIRED-001");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetHistoryAsync_ShouldReturnEventsInOrder()
    {
        // Arrange
        var exception = CreateException("EXC-HISTORY-001");
        await _repository.CreateAsync(exception, "creator");

        var updated = exception with
        {
            Version = 2,
            Status = ExceptionStatus.Approved,
            ApprovedAt = DateTimeOffset.UtcNow,
            ApproverIds = ["approver@example.com"],
            UpdatedAt = DateTimeOffset.UtcNow
        };
        await _repository.UpdateAsync(updated, ExceptionEventType.Approved, "approver");

        var activated = updated with
        {
            Version = 3,
            Status = ExceptionStatus.Active,
            UpdatedAt = DateTimeOffset.UtcNow
        };
        await _repository.UpdateAsync(activated, ExceptionEventType.Activated, "activator");

        // Act
        var history = await _repository.GetHistoryAsync("EXC-HISTORY-001");

        // Assert
        history.EventCount.Should().Be(3);
        history.Events[0].EventType.Should().Be(ExceptionEventType.Created);
        history.Events[1].EventType.Should().Be(ExceptionEventType.Approved);
        history.Events[2].EventType.Should().Be(ExceptionEventType.Activated);
        history.Events[0].SequenceNumber.Should().Be(1);
        history.Events[1].SequenceNumber.Should().Be(2);
        history.Events[2].SequenceNumber.Should().Be(3);
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task GetCountsAsync_ShouldReturnCorrectCounts()
    {
        // Arrange
        await _repository.CreateAsync(CreateException("EXC-COUNT-001", status: ExceptionStatus.Proposed), "actor");
        await _repository.CreateAsync(CreateException("EXC-COUNT-002", status: ExceptionStatus.Proposed), "actor");
        await _repository.CreateAsync(CreateException("EXC-COUNT-003", status: ExceptionStatus.Active), "actor");
        await _repository.CreateAsync(CreateException("EXC-COUNT-004", status: ExceptionStatus.Revoked), "actor");
        await _repository.CreateAsync(CreateException("EXC-COUNT-005", status: ExceptionStatus.Active, 
            expiresAt: DateTimeOffset.UtcNow.AddDays(3)), "actor");

        // Act
        var counts = await _repository.GetCountsAsync();

        // Assert
        counts.Total.Should().Be(5);
        counts.Proposed.Should().Be(2);
        counts.Active.Should().Be(2);
        counts.Revoked.Should().Be(1);
        counts.ExpiringSoon.Should().BeGreaterThanOrEqualTo(1); // At least the one expiring in 3 days
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task CreateAsync_WithMetadata_ShouldPersistCorrectly()
    {
        // Arrange
        var metadata = ImmutableDictionary<string, string>.Empty
            .Add("team", "security")
            .Add("priority", "high")
            .Add("ticket", "SEC-123");

        var exception = CreateException("EXC-META-001", metadata: metadata);

        // Act
        await _repository.CreateAsync(exception, "actor");
        var fetched = await _repository.GetByIdAsync("EXC-META-001");

        // Assert
        fetched!.Metadata.Should().HaveCount(3);
        fetched.Metadata["team"].Should().Be("security");
        fetched.Metadata["priority"].Should().Be("high");
        fetched.Metadata["ticket"].Should().Be("SEC-123");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task CreateAsync_WithEvidenceRefs_ShouldPersistCorrectly()
    {
        // Arrange
        var evidenceRefs = ImmutableArray.Create(
            "sha256:evidence1",
            "sha256:evidence2",
            "https://evidence.example.com/doc1");

        var exception = CreateException("EXC-EVIDENCE-001", evidenceRefs: evidenceRefs);

        // Act
        await _repository.CreateAsync(exception, "actor");
        var fetched = await _repository.GetByIdAsync("EXC-EVIDENCE-001");

        // Assert
        fetched!.EvidenceRefs.Should().HaveCount(3);
        fetched.EvidenceRefs.Should().Contain("sha256:evidence1");
        fetched.EvidenceRefs.Should().Contain("https://evidence.example.com/doc1");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task CreateAsync_WithCompensatingControls_ShouldPersistCorrectly()
    {
        // Arrange
        var controls = ImmutableArray.Create(
            "WAF blocking malicious patterns",
            "Network segmentation prevents lateral movement");

        var exception = CreateException("EXC-CONTROLS-001", compensatingControls: controls);

        // Act
        await _repository.CreateAsync(exception, "actor");
        var fetched = await _repository.GetByIdAsync("EXC-CONTROLS-001");

        // Assert
        fetched!.CompensatingControls.Should().HaveCount(2);
        fetched.CompensatingControls.Should().Contain("WAF blocking malicious patterns");
    }

    [Trait("Category", TestCategories.Unit)]
        [Fact]
    public async Task CreateAsync_WithEnvironments_ShouldPersistCorrectly()
    {
        // Arrange
        var environments = ImmutableArray.Create("dev", "staging");
        var exception = CreateException("EXC-ENV-001", environments: environments);

        // Act
        await _repository.CreateAsync(exception, "actor");
        var fetched = await _repository.GetByIdAsync("EXC-ENV-001");

        // Assert
        fetched!.Scope.Environments.Should().HaveCount(2);
        fetched.Scope.Environments.Should().Contain(["dev", "staging"]);
    }

    #region Test Helpers

    private static readonly Guid TestTenantId = Guid.Parse("11111111-1111-1111-1111-111111111111");

    private static ExceptionObject CreateException(
        string exceptionId,
        ExceptionStatus status = ExceptionStatus.Proposed,
        ExceptionType type = ExceptionType.Vulnerability,
        string vulnerabilityId = "CVE-2024-12345",
        DateTimeOffset? expiresAt = null,
        ImmutableDictionary<string, string>? metadata = null,
        ImmutableArray<string>? evidenceRefs = null,
        ImmutableArray<string>? compensatingControls = null,
        ImmutableArray<string>? environments = null)
    {
        return new ExceptionObject
        {
            ExceptionId = exceptionId,
            Version = 1,
            Status = status,
            Type = type,
            Scope = new ExceptionScope
            {
                VulnerabilityId = vulnerabilityId,
                Environments = environments ?? [],
                TenantId = TestTenantId
            },
            OwnerId = "owner@example.com",
            RequesterId = "requester@example.com",
            CreatedAt = DateTimeOffset.UtcNow,
            UpdatedAt = DateTimeOffset.UtcNow,
            ExpiresAt = expiresAt ?? DateTimeOffset.UtcNow.AddDays(30),
            ReasonCode = ExceptionReason.AcceptedRisk,
            Rationale = "This is a test rationale that meets the minimum character requirement of 50 characters.",
            EvidenceRefs = evidenceRefs ?? [],
            CompensatingControls = compensatingControls ?? [],
            Metadata = metadata ?? ImmutableDictionary<string, string>.Empty
        };
    }

    #endregion
}