using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Mvc.Testing;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using ZB.MOM.WW.ScadaBridge.ConfigurationDatabase;

namespace ZB.MOM.WW.ScadaBridge.Host.Tests;

/// <summary>
/// Deferred register row 50, mitigation 1: .NET's built-in DI scope validation is on in
/// Development for BOTH composition roots, and both roots actually survive it.
/// </summary>
/// <remarks>
/// The build-and-validate form is the load-bearing one. Asserting that
/// <c>ValidateScopes</c> is set proves only that a flag was written; asserting that the
/// full Central and Site graphs BUILD with <c>ValidateOnBuild</c> on is what proves there
/// is no latent singleton-captures-scoped violation to be surfaced — and it keeps
/// proving it as registrations are added, on every CI run, without anyone having to boot
/// a node in Development.
///
/// Both roles force the flags on explicitly rather than relying on the environment, so
/// the check runs identically in CI (where the environment is whatever the runner
/// inherits) and so a future change to the environment plumbing cannot silently turn the
/// coverage off — the exact failure mode this row is about.
/// </remarks>
public class ServiceProviderValidationOptionsTests
{
    [Fact]
    public void Apply_InDevelopment_EnablesBothValidations()
    {
        var options = new ServiceProviderOptions();

        ServiceProviderValidation.Apply(options, isDevelopment: true);

        Assert.True(options.ValidateScopes);
        Assert.True(options.ValidateOnBuild);
    }

    [Fact]
    public void Apply_OutsideDevelopment_LeavesBothValidationsOff()
    {
        // Production pays neither the per-resolve scope check nor the boot-time graph
        // walk, and — more importantly — a validation failure cannot fail a production
        // node closed at boot. See ServiceProviderValidation's remarks.
        var options = new ServiceProviderOptions { ValidateScopes = true, ValidateOnBuild = true };

        ServiceProviderValidation.Apply(options, isDevelopment: false);

        Assert.False(options.ValidateScopes);
        Assert.False(options.ValidateOnBuild);
    }
}

/// <summary>
/// Builds the REAL Central composition root (the whole <c>Program.cs</c> Central branch)
/// with scope + build validation forced on, and asserts it builds clean.
/// </summary>
[Collection(HostBootCollection.Name)]
public class CentralServiceProviderValidationTests : IDisposable
{
    private readonly string? _previousEnv;
    private readonly CentralDbTestEnvironment _dbEnv;
    private WebApplicationFactory<Program>? _factory;

    public CentralServiceProviderValidationTests()
    {
        _previousEnv = Environment.GetEnvironmentVariable("DOTNET_ENVIRONMENT");
        Environment.SetEnvironmentVariable("DOTNET_ENVIRONMENT", "Central");
        _dbEnv = new CentralDbTestEnvironment();
    }

    public void Dispose()
    {
        try
        {
            _factory?.Dispose();
        }
        finally
        {
            Environment.SetEnvironmentVariable("DOTNET_ENVIRONMENT", _previousEnv);
            _dbEnv.Dispose();
        }
    }

    /// <summary>
    /// A captive dependency anywhere in the Central graph — a singleton whose constructor
    /// takes a scoped service — makes <c>ValidateOnBuild</c> throw an
    /// <see cref="AggregateException"/> here listing every offender, so this test names
    /// the violation rather than leaving it to be found by a rig log line months later
    /// (which is how row 45 was found).
    /// </summary>
    [Fact]
    public void Central_CompositionRoot_BuildsWithScopeValidationEnabled()
    {
        _factory = new WebApplicationFactory<Program>()
            .WithWebHostBuilder(builder =>
            {
                // Force the flags on regardless of the runner's environment. This is the
                // same configuration Program.cs applies in Development, exercised here as
                // a hard assertion.
                builder.UseDefaultServiceProvider(options =>
                {
                    options.ValidateScopes = true;
                    options.ValidateOnBuild = true;
                });

                builder.ConfigureAppConfiguration((_, config) =>
                {
                    config.AddInMemoryCollection(new Dictionary<string, string?>
                    {
                        ["ScadaBridge:Node:NodeName"] = "central-a",
                        ["ScadaBridge:Node:NodeHostname"] = "localhost",
                        ["ScadaBridge:Node:RemotingPort"] = "0",
                        ["ScadaBridge:Cluster:SeedNodes:0"] = "akka.tcp://scadabridge@localhost:2551",
                        ["ScadaBridge:Cluster:SeedNodes:1"] = "akka.tcp://scadabridge@localhost:2552",
                        ["ScadaBridge:Database:SkipMigrations"] = "true",
                        ["ScadaBridge:Security:JwtSigningKey"] = "test-signing-key-must-be-at-least-32-chars-long!",
                        ["ScadaBridge:Security:Ldap:Server"] = "localhost",
                        ["ScadaBridge:Security:Ldap:Port"] = "3893",
                        ["ScadaBridge:Security:Ldap:Transport"] = "None",
                        ["ScadaBridge:Security:Ldap:AllowInsecure"] = "true",
                        ["ScadaBridge:Security:Ldap:SearchBase"] = "dc=zb,dc=local",
                        ["ScadaBridge:Security:Ldap:ServiceAccountDn"] = "cn=admin,dc=zb,dc=local",
                        ["ScadaBridge:InboundApi:ApiKeyPepper"] = "test-inbound-api-key-pepper-at-least-32-chars!",
                    });
                });
                builder.UseSetting("ScadaBridge:Node:Role", "Central");
                builder.UseSetting("ScadaBridge:Database:SkipMigrations", "true");
                builder.ConfigureServices(services =>
                {
                    var descriptorsToRemove = services
                        .Where(d =>
                            d.ServiceType == typeof(DbContextOptions<ScadaBridgeDbContext>) ||
                            d.ServiceType == typeof(DbContextOptions) ||
                            d.ServiceType == typeof(ScadaBridgeDbContext) ||
                            d.ServiceType.FullName?.Contains("EntityFrameworkCore") == true)
                        .ToList();
                    foreach (var d in descriptorsToRemove)
                        services.Remove(d);

                    services.AddDbContext<ScadaBridgeDbContext>(options =>
                        options.UseInMemoryDatabase($"ScopeValidation_{Guid.NewGuid()}"));

                    AkkaHostedServiceRemover.RemoveAkkaHostedServiceOnly(services);
                });
            });

        // Building the server is the assertion: ValidateOnBuild throws from
        // BuildServiceProvider, and ValidateScopes throws on the first offending resolve.
        var services = _factory.Services;
        Assert.NotNull(services);
    }
}

/// <summary>
/// The Site half. This is the branch that actually gains coverage from the Program.cs
/// change: the docker rig sets <c>ASPNETCORE_ENVIRONMENT=Development</c> on the central
/// containers but not on the site containers, so a site node has always built its
/// provider unvalidated.
/// </summary>
public class SiteServiceProviderValidationTests : IDisposable
{
    private readonly string _tempDbPath;
    private readonly string _tempTrackingDbPath;
    private readonly string _tempLocalDbPath;
    private readonly string _tempAuditDbPath;
    private WebApplication? _host;

    public SiteServiceProviderValidationTests()
    {
        _tempDbPath = Path.Combine(Path.GetTempPath(), $"sb_scopeval_{Guid.NewGuid()}.db");
        _tempTrackingDbPath = Path.Combine(Path.GetTempPath(), $"sb_scopeval_track_{Guid.NewGuid()}.db");
        _tempLocalDbPath = Path.Combine(Path.GetTempPath(), $"sb_scopeval_localdb_{Guid.NewGuid()}.db");
        _tempAuditDbPath = Path.Combine(Path.GetTempPath(), $"sb_scopeval_audit_{Guid.NewGuid()}.db");
    }

    public void Dispose()
    {
        (_host as IDisposable)?.Dispose();
        foreach (var path in new[] { _tempDbPath, _tempTrackingDbPath, _tempLocalDbPath, _tempAuditDbPath })
        {
            try { File.Delete(path); } catch { /* best effort */ }
        }
    }

    [Fact]
    public void Site_CompositionRoot_BuildsWithScopeValidationEnabled()
    {
        var builder = WebApplication.CreateBuilder();
        builder.Configuration.Sources.Clear();
        builder.Configuration.AddInMemoryCollection(new Dictionary<string, string?>
        {
            ["ScadaBridge:Node:Role"] = "Site",
            ["ScadaBridge:Node:NodeName"] = "node-a",
            ["ScadaBridge:Node:NodeHostname"] = "test-site",
            ["ScadaBridge:Node:SiteId"] = "TestSite",
            ["ScadaBridge:Node:RemotingPort"] = "0",
            ["ScadaBridge:Node:GrpcPort"] = "0",
            ["ScadaBridge:Database:SiteDbPath"] = _tempDbPath,
            ["ScadaBridge:OperationTracking:ConnectionString"] = $"Data Source={_tempTrackingDbPath}",
            ["LocalDb:Path"] = _tempLocalDbPath,
            ["AuditLog:SiteWriter:DatabasePath"] = _tempAuditDbPath,
            ["ScadaBridge:Cluster:SeedNodes:0"] = "akka.tcp://scadabridge@localhost:2551",
            ["ScadaBridge:Cluster:SeedNodes:1"] = "akka.tcp://scadabridge@localhost:2552",
        });

        // The production Program.cs Site branch applies this via
        // ServiceProviderValidation.Configure; forced on here so the check does not depend
        // on the test runner's environment.
        builder.Host.UseDefaultServiceProvider(options =>
        {
            options.ValidateScopes = true;
            options.ValidateOnBuild = true;
        });

        // Mirrors the Program.cs site section.
        builder.Services.AddGrpc();
        builder.Services.AddSingleton<ZB.MOM.WW.ScadaBridge.Communication.Grpc.SiteStreamGrpcServer>();
        builder.Services.AddSingleton<ZB.MOM.WW.ScadaBridge.Communication.Grpc.SiteCommandGrpcService>();

        SiteServiceRegistration.Configure(builder.Services, builder.Configuration);
        AkkaHostedServiceRemover.RemoveAkkaHostedServiceOnly(builder.Services);

        // Build is the assertion — ValidateOnBuild throws here if anything in the site
        // graph is a captive dependency.
        _host = builder.Build();
        Assert.NotNull(_host.Services);
    }
}