using Xunit;
using Dapper;
using Npgsql;
using KArtSell.Modules.IdentityAccess.ManageIdentityAndRoles.Features.RegisterIdentity;
using KArtSell.BuildingBlocks.Reliability;
using KArtSell.BuildingBlocks.Data;
using System.Data;
using System.Text.Json;

namespace KArtSell.IdentityAccess.IntegrationTests.Features;

[Collection("Database")]
public class RegisterIdentityE2ETests : IAsyncLifetime
{
    private readonly string _connectionString;
    private NpgsqlDataSource _dataSource = null!;
    private RegisterIdentitySql _sql = null!;
    private IOutboxWriter _outboxWriter = null!;
    private IDbConnectionFactory _connectionFactory = null!;

    public RegisterIdentityE2ETests()
    {
        _connectionString = Environment.GetEnvironmentVariable("KARTSELL_POSTGRES")
            ?? "Host=127.0.0.1;Port=5432;Database=kartselldb;Username=postgres;Password=postgres";
    }

    public async Task InitializeAsync()
    {
        _dataSource = new NpgsqlDataSourceBuilder(_connectionString).Build();
        _sql = new RegisterIdentitySql(async () => await _dataSource.OpenConnectionAsync());
        _outboxWriter = new DapperOutboxWriter();
        _connectionFactory = new NpgsqlConnectionFactory(_dataSource);

        await CleanupAsync();
    }

    public async Task DisposeAsync()
    {
        await CleanupAsync();
        await _dataSource.DisposeAsync();
    }

    private async Task CleanupAsync()
    {
        using var conn = await _dataSource.OpenConnectionAsync();
        await conn.ExecuteAsync("DELETE FROM public.identity WHERE email LIKE 'test-e2e-%'");
        await conn.ExecuteAsync("DELETE FROM building_blocks.outbox_message WHERE event_type = 'IdentityCreated'");
        await conn.ExecuteAsync("DELETE FROM building_blocks.inbox_message WHERE event_type = 'IdentityCreated'");
        await conn.ExecuteAsync("DELETE FROM public.identity_audit_log WHERE email LIKE 'test-e2e-%'");
        await conn.ExecuteAsync("DELETE FROM public.identity_mfa_reminder");
    }

    [Fact]
    public async Task RegisterIdentity_E2E_CreatesIdentityWritesOutboxAndTriggersConsumers()
    {
        // Arrange
        var email = "test-e2e-001@example.com";
        var displayName = "Test E2E 001";
        var correlationId = Guid.NewGuid().ToString();
        var identityId = Guid.NewGuid();

        // Act: Create identity with outbox write
        var conn = await _dataSource.OpenConnectionAsync() as NpgsqlConnection
            ?? throw new InvalidOperationException("Failed to open connection");

        await using (conn)
        {
            await using var transaction = await conn.BeginTransactionAsync(IsolationLevel.ReadCommitted);

            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);

            var identityCreatedEvent = new KArtSell.Modules.IdentityAccess.ManageIdentityAndRoles.Events.IdentityCreated
            {
                IdentityId = createdId,
                Email = email,
                DisplayName = displayName,
                CorrelationId = correlationId,
                OccurredAt = DateTime.UtcNow
            };

            var payloadJson = JsonSerializer.Serialize(identityCreatedEvent);
            var outboxMessage = new OutboxMessage(
                MessageId: Guid.NewGuid(),
                EventType: "IdentityCreated",
                SchemaVersion: 1,
                PayloadJson: payloadJson,
                CorrelationId: correlationId,
                OccurredAt: DateTimeOffset.UtcNow,
                PayloadHash: ComputeSha256(payloadJson));

            await _outboxWriter.AddAsync(conn, transaction, outboxMessage, CancellationToken.None);
            await transaction.CommitAsync();

            // Assert: Verify identity was created
            var (returnedId, returnedEmail, _, returnedState) = await _sql.GetIdentityAsync(createdId, CancellationToken.None);
            Assert.Equal(createdId, returnedId);
            Assert.Equal(email, returnedEmail);
            Assert.Equal("ACTIVE", returnedState);

            // Assert: Verify outbox message was written
            var outboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.outbox_message WHERE correlation_id = @correlationId",
                new { correlationId });
            Assert.Equal(1, outboxCount);
        }
    }

    [Fact]
    public async Task RegisterIdentity_E2E_OutboxPollerMarksInboxAndTriggersConsumers()
    {
        // Arrange: Create identity with outbox
        var email = "test-e2e-002@example.com";
        var displayName = "Test E2E 002";
        var correlationId = Guid.NewGuid().ToString();
        var identityId = Guid.NewGuid();
        var messageId = Guid.NewGuid();

        var conn = await _dataSource.OpenConnectionAsync() as NpgsqlConnection
            ?? throw new InvalidOperationException("Failed to open connection");

        await using (conn)
        {
            await using var transaction = await conn.BeginTransactionAsync(IsolationLevel.ReadCommitted);

            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);

            var identityCreatedEvent = new KArtSell.Modules.IdentityAccess.ManageIdentityAndRoles.Events.IdentityCreated
            {
                IdentityId = createdId,
                Email = email,
                DisplayName = displayName,
                CorrelationId = correlationId,
                OccurredAt = DateTime.UtcNow
            };

            var payloadJson = JsonSerializer.Serialize(identityCreatedEvent);
            var outboxMessage = new OutboxMessage(
                MessageId: messageId,
                EventType: "IdentityCreated",
                SchemaVersion: 1,
                PayloadJson: payloadJson,
                CorrelationId: correlationId,
                OccurredAt: DateTimeOffset.UtcNow,
                PayloadHash: ComputeSha256(payloadJson));

            await _outboxWriter.AddAsync(conn, transaction, outboxMessage, CancellationToken.None);
            await transaction.CommitAsync();

            // Act: Manually insert inbox record (simulating OutboxPollerJob)
            const string inboxSql = """
                INSERT INTO building_blocks.inbox_message (message_id, event_type, payload_json, received_at, consumer)
                VALUES (@MessageId, 'IdentityCreated', @PayloadJson, NOW(), 'outbox-poller')
                """;

            await conn.ExecuteAsync(inboxSql, new { messageId, payloadJson });

            // Assert: Verify inbox message was created
            var inboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.inbox_message WHERE message_id = @messageId",
                new { messageId });
            Assert.Equal(1, inboxCount);

            // Assert: Verify we can read the inbox message
            var inboxMessage = await conn.QuerySingleOrDefaultAsync<(Guid MessageId, string PayloadJson)>(
                """
                SELECT message_id, payload_json
                FROM building_blocks.inbox_message
                WHERE message_id = @MessageId
                """,
                new { messageId });

            Assert.NotEqual(default, inboxMessage);
            Assert.Equal(payloadJson, inboxMessage.PayloadJson);
        }
    }

    [Fact]
    public async Task RegisterIdentity_E2E_FullFlowCreatesAuditAndMfaRecords()
    {
        // Arrange: Create identity with outbox in transaction
        var email = "test-e2e-003@example.com";
        var displayName = "Test E2E 003";
        var correlationId = Guid.NewGuid().ToString();
        var identityId = Guid.NewGuid();

        var conn = await _dataSource.OpenConnectionAsync() as NpgsqlConnection
            ?? throw new InvalidOperationException("Failed to open connection");

        await using (conn)
        {
            // Step 1: Create identity + write to outbox (transactional)
            await using var transaction = await conn.BeginTransactionAsync(IsolationLevel.ReadCommitted);

            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);

            var identityCreatedEvent = new KArtSell.Modules.IdentityAccess.ManageIdentityAndRoles.Events.IdentityCreated
            {
                IdentityId = createdId,
                Email = email,
                DisplayName = displayName,
                CorrelationId = correlationId,
                OccurredAt = DateTime.UtcNow
            };

            var payloadJson = JsonSerializer.Serialize(identityCreatedEvent);
            var outboxMessage = new OutboxMessage(
                MessageId: Guid.NewGuid(),
                EventType: "IdentityCreated",
                SchemaVersion: 1,
                PayloadJson: payloadJson,
                CorrelationId: correlationId,
                OccurredAt: DateTimeOffset.UtcNow,
                PayloadHash: ComputeSha256(payloadJson));

            await _outboxWriter.AddAsync(conn, transaction, outboxMessage, CancellationToken.None);
            await transaction.CommitAsync();

            // Step 2: Simulate DownstreamConsumerJob reading outbox → inbox
            const string inboxSql = """
                INSERT INTO building_blocks.inbox_message (message_id, event_type, payload_json, received_at, consumer)
                SELECT message_id, event_type, payload_json, NOW(), 'outbox-poller'
                FROM building_blocks.outbox_message
                WHERE event_type = 'IdentityCreated' AND correlation_id = @correlationId
                """;

            await conn.ExecuteAsync(inboxSql, new { correlationId });

            // Step 3: Simulate DownstreamConsumerJob calling consumers
            // Write audit log (simulating IdentityAuditConsumer)
            const string auditSql = """
                INSERT INTO public.identity_audit_log (identity_id, action, email, display_name, correlation_id, occurred_at)
                VALUES (@identityId, 'CREATED', @email, @displayName, @correlationId, @occurredAt)
                """;

            await conn.ExecuteAsync(auditSql, new
            {
                identityId = createdId,
                email,
                displayName,
                correlationId,
                occurredAt = identityCreatedEvent.OccurredAt
            });

            // Write MFA reminder tracking (simulating MfaReminderJob)
            const string mfaSql = """
                INSERT INTO public.identity_mfa_reminder (identity_id, sent_at)
                VALUES (@identityId, NOW())
                ON CONFLICT (identity_id) DO NOTHING
                """;

            await conn.ExecuteAsync(mfaSql, new { identityId = createdId });

            // Assert: Verify complete E2E flow
            var identity = await _sql.GetIdentityAsync(createdId, CancellationToken.None);
            Assert.Equal(email, identity.Email);

            var outboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.outbox_message WHERE correlation_id = @correlationId",
                new { correlationId });
            Assert.Equal(1, outboxCount);

            var inboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.inbox_message WHERE event_type = 'IdentityCreated'");
            Assert.True(inboxCount > 0);

            var auditCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM public.identity_audit_log WHERE identity_id = @identityId AND action = 'CREATED'",
                new { identityId = createdId });
            Assert.Equal(1, auditCount);

            var mfaCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM public.identity_mfa_reminder WHERE identity_id = @identityId",
                new { identityId = createdId });
            Assert.Equal(1, mfaCount);
        }
    }

    [Fact]
    public async Task RegisterIdentity_E2E_MfaReminderIsIdempotent()
    {
        // Arrange
        var email = "test-e2e-004@example.com";
        var displayName = "Test E2E 004";
        var correlationId = Guid.NewGuid().ToString();
        var identityId = Guid.NewGuid();

        var conn = await _dataSource.OpenConnectionAsync() as NpgsqlConnection
            ?? throw new InvalidOperationException("Failed to open connection");

        await using (conn)
        {
            // Create identity first
            await using var transaction = await conn.BeginTransactionAsync(IsolationLevel.ReadCommitted);
            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);
            await transaction.CommitAsync();

            // Act: Record MFA reminder twice (should be idempotent)
            const string mfaSql = """
                INSERT INTO public.identity_mfa_reminder (identity_id, sent_at)
                VALUES (@identityId, NOW())
                ON CONFLICT (identity_id) DO NOTHING
                """;

            await conn.ExecuteAsync(mfaSql, new { identityId = createdId });
            await conn.ExecuteAsync(mfaSql, new { identityId = createdId });

            // Assert: Only one record exists
            var mfaCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM public.identity_mfa_reminder WHERE identity_id = @identityId",
                new { identityId = createdId });
            Assert.Equal(1, mfaCount);
        }
    }

    [Fact]
    public async Task RegisterIdentity_E2E_AuditLogIsImmutable()
    {
        // Arrange
        var email = "test-e2e-005@example.com";
        var displayName = "Test E2E 005";
        var correlationId = Guid.NewGuid().ToString();
        var identityId = Guid.NewGuid();

        var conn = await _dataSource.OpenConnectionAsync() as NpgsqlConnection
            ?? throw new InvalidOperationException("Failed to open connection");

        await using (conn)
        {
            // Create identity
            await using var transaction = await conn.BeginTransactionAsync(IsolationLevel.ReadCommitted);
            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);
            await transaction.CommitAsync();

            // Insert audit record
            const string auditSql = """
                INSERT INTO public.identity_audit_log (identity_id, action, email, display_name, correlation_id, occurred_at)
                VALUES (@identityId, 'CREATED', @email, @displayName, @correlationId, NOW())
                """;

            await conn.ExecuteAsync(auditSql, new
            {
                identityId = createdId,
                email,
                displayName,
                correlationId
            });

            // Act: Try to update audit record (should fail due to trigger)
            const string updateAuditSql = """
                UPDATE public.identity_audit_log SET action = 'MODIFIED' WHERE identity_id = @identityId
                """;

            var ex = await Assert.ThrowsAsync<PostgresException>(async () =>
                await conn.ExecuteAsync(updateAuditSql, new { identityId = createdId }));

            // Assert: Exception should mention immutability
            Assert.Contains("immutable", ex.Message, StringComparison.OrdinalIgnoreCase);
        }
    }

    private static string ComputeSha256(string input)
    {
        using var hasher = System.Security.Cryptography.SHA256.Create();
        var hash = hasher.ComputeHash(System.Text.Encoding.UTF8.GetBytes(input));
        return Convert.ToHexString(hash);
    }
}