using Xunit;
using Dapper;
using Npgsql;
using KArtSell.Modules.IdentityAccess.ManageIdentityAndRoles.Features.RegisterIdentity;
using KArtSell.BuildingBlocks.Reliability;

namespace KArtSell.IdentityAccess.IntegrationTests.Features;

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

    public RegisterIdentityWithOutboxIntegrationTests()
    {
        _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();

        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-outbox-%'");
        await conn.ExecuteAsync("DELETE FROM building_blocks.outbox_message WHERE event_type = 'IdentityCreated'");
    }

    [Fact]
    public async Task RegisterIdentity_WithOutbox_WritesToBoth()
    {
        var email = "test-outbox-001@example.com";
        var displayName = "Test Outbox 001";
        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)
        {
            await using var transaction = await conn.BeginTransactionAsync();

            // Create identity
            var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);
            Assert.NotEqual(Guid.Empty, createdId);

            // Write outbox message
            var outboxMessage = new OutboxMessage(
                MessageId: Guid.NewGuid(),
                EventType: "IdentityCreated",
                SchemaVersion: 1,
                PayloadJson: System.Text.Json.JsonSerializer.Serialize(new { identityId, email, displayName, correlationId }),
                CorrelationId: correlationId,
                OccurredAt: DateTimeOffset.UtcNow,
                PayloadHash: ComputeSha256("test-payload"));

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

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

            // 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_RollbackOnError_RevertsBothIdentityAndOutbox()
    {
        var email = "test-outbox-002@example.com";
        var displayName = "Test Outbox 002";
        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)
        {
            await using var transaction = await conn.BeginTransactionAsync();

            try
            {
                var createdId = await _sql.CreateIdentityAsync(conn, transaction, identityId, email, displayName, correlationId, CancellationToken.None);
                Assert.NotEqual(Guid.Empty, createdId);

                // Write outbox message
                var outboxMessage = new OutboxMessage(
                    MessageId: Guid.NewGuid(),
                    EventType: "IdentityCreated",
                    SchemaVersion: 1,
                    PayloadJson: System.Text.Json.JsonSerializer.Serialize(new { identityId, email, displayName, correlationId }),
                    CorrelationId: correlationId,
                    OccurredAt: DateTimeOffset.UtcNow,
                    PayloadHash: ComputeSha256("test-payload"));

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

                // Simulate error: force rollback
                throw new InvalidOperationException("Simulated error");
            }
            catch (InvalidOperationException)
            {
                await transaction.RollbackAsync();
            }

            // Verify identity was NOT created (rolled back)
            var identityExists = await conn.QuerySingleAsync<bool>(
                "SELECT COUNT(1) > 0 FROM public.identity WHERE email = @email",
                new { email });
            Assert.False(identityExists);

            // Verify outbox message was NOT written (rolled back)
            var outboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.outbox_message WHERE correlation_id = @correlationId",
                new { correlationId });
            Assert.Equal(0, outboxCount);
        }
    }

    [Fact]
    public async Task RegisterIdentity_DuplicateEmail_NoOutboxWrite()
    {
        var email = "test-outbox-003@example.com";
        var displayName = "Test Outbox 003";
        var correlationId1 = Guid.NewGuid().ToString();
        var correlationId2 = Guid.NewGuid().ToString();
        var identityId1 = Guid.NewGuid();
        var identityId2 = Guid.NewGuid();

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

        await using (conn)
        {
            // First registration: succeeds
            await using (var tx1 = await conn.BeginTransactionAsync())
            {
                await _sql.CreateIdentityAsync(conn, tx1, identityId1, email, displayName, correlationId1, CancellationToken.None);
                var msg1 = new OutboxMessage(Guid.NewGuid(), "IdentityCreated", 1,
                    System.Text.Json.JsonSerializer.Serialize(new { identityId1, email, displayName, correlationId1 }),
                    correlationId1, DateTimeOffset.UtcNow, ComputeSha256("test"));
                await _outboxWriter.AddAsync(conn, tx1, msg1, CancellationToken.None);
                await tx1.CommitAsync();
            }

            // Second registration: fails (duplicate email), should not write outbox
            await using (var tx2 = await conn.BeginTransactionAsync())
            {
                var result = await _sql.CreateIdentityAsync(conn, tx2, identityId2, email, displayName, correlationId2, CancellationToken.None);
                Assert.Equal(Guid.Empty, result);  // Conflict, returns empty
                // Don't write to outbox if creation failed
                await tx2.CommitAsync();
            }

            // Verify only first outbox message exists
            var outboxCount = await conn.QuerySingleAsync<int>(
                "SELECT COUNT(1) FROM building_blocks.outbox_message WHERE event_type = 'IdentityCreated'");
            Assert.Equal(1, outboxCount);
        }
    }

    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);
    }
}