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

namespace ZB.MOM.WW.ScadaBridge.IntegrationTests;

/// <summary>
/// Shared WebApplicationFactory for integration tests.
/// Replaces SQL Server with an in-memory database and skips migrations.
/// Removes AkkaHostedService to avoid DNS resolution issues in test environments.
/// Uses environment variables for config since Program.cs reads them in the initial ConfigurationBuilder
/// before WebApplicationFactory can inject settings.
/// </summary>
public class ScadaBridgeWebApplicationFactory : WebApplicationFactory<Program>
{
    /// <summary>
    /// Environment variables that were set by this factory, to be cleaned up on dispose.
    /// </summary>
    private readonly Dictionary<string, string?> _previousEnvVars = new();

    public ScadaBridgeWebApplicationFactory()
    {
        // The initial ConfigurationBuilder in Program.cs reads env vars with AddEnvironmentVariables().
        // The env var format uses __ as section separator.
        var envVars = new Dictionary<string, string>
        {
            ["DOTNET_ENVIRONMENT"] = "Development",
            ["ScadaBridge__Node__Role"] = "Central",
            ["ScadaBridge__Node__NodeHostname"] = "localhost",
            ["ScadaBridge__Node__RemotingPort"] = "8081",
            ["ScadaBridge__Cluster__SeedNodes__0"] = "akka.tcp://scadabridge@localhost:8081",
            ["ScadaBridge__Cluster__SeedNodes__1"] = "akka.tcp://scadabridge@localhost:8082",
            ["ScadaBridge__Database__ConfigurationDb"] = "Server=localhost;Database=ScadaBridge_Test;TrustServerCertificate=True",
            ["ScadaBridge__Database__MachineDataDb"] = "Server=localhost;Database=ScadaBridge_MachineData_Test;TrustServerCertificate=True",
            ["ScadaBridge__Database__SkipMigrations"] = "true",
            ["ScadaBridge__Security__JwtSigningKey"] = "integration-test-signing-key-must-be-at-least-32-chars-long",
            // Task 1.4: LDAP settings nest under Security:Ldap (shared LdapOptions) and use
            // the renamed keys (Transport replaces LdapUseTls; None == plaintext for the
            // GLAuth dev directory, paired with AllowInsecure=true).
            ["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",
            // GLAuth places users at cn=<name>,ou=<group>,ou=users,dc=... — a service
            // account is configured to enable the shared service's search-then-bind:
            // resolve the user's real DN by (UserNameAttribute=<name>) lookup, then bind it.
            ["ScadaBridge__Security__Ldap__ServiceAccountDn"] = "cn=admin,ou=SCADA-Admins,ou=users,dc=zb,dc=local",
            ["ScadaBridge__Security__Ldap__ServiceAccountPassword"] = "password",
        };

        foreach (var (key, value) in envVars)
        {
            _previousEnvVars[key] = Environment.GetEnvironmentVariable(key);
            Environment.SetEnvironmentVariable(key, value);
        }
    }

    protected override void ConfigureWebHost(IWebHostBuilder builder)
    {
        builder.UseEnvironment("Development");

        builder.ConfigureServices(services =>
        {
            // Remove ALL DbContext and EF-related service registrations to avoid dual-provider conflict.
            // AddDbContext<> with UseSqlServer registers many internal services. We must remove them all.
            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);

            // Add in-memory database as sole provider
            services.AddDbContext<ScadaBridgeDbContext>(options =>
                options.UseInMemoryDatabase($"ScadaBridge_IntegrationTests_{Guid.NewGuid()}"));

            // Remove the factory-registered IHostedService registrations so
            // Akka.NET remoting / DNS resolution never starts in tests — but
            // keep the AkkaHostedService SINGLETON resolvable: IClusterNodeProvider
            // (and other services) depend on it via GetRequiredService.
            var hostedServiceDescriptors = services
                .Where(d => d.ServiceType == typeof(IHostedService) && d.ImplementationFactory != null)
                .ToList();
            foreach (var d in hostedServiceDescriptors)
                services.Remove(d);
        });
    }

    protected override void Dispose(bool disposing)
    {
        base.Dispose(disposing);
        if (disposing)
        {
            foreach (var (key, previousValue) in _previousEnvVars)
            {
                Environment.SetEnvironmentVariable(key, previousValue);
            }
        }
    }
}