using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Authentication.Cookies;
using Microsoft.AspNetCore.Authorization;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.Options;
using ZB.MOM.WW.Auth.Abstractions.Roles;
using ZB.MOM.WW.Auth.AspNetCore;
using ZB.MOM.WW.MxGateway.Server.Configuration;
using ZB.MOM.WW.MxGateway.Server.Security.Audit;

namespace ZB.MOM.WW.MxGateway.Server.Dashboard;

/// <summary>
/// Extension methods for configuring the gateway dashboard services.
/// </summary>
public static class DashboardServiceCollectionExtensions
{
    /// <summary>
    /// Registers all dashboard services, authentication, and Razor components.
    /// </summary>
    /// <param name="services">Service collection to register services.</param>
    /// <param name="configuration">
    /// Application configuration, used to bind the shared LDAP provider's options
    /// from the <c>MxGateway:Ldap</c> section.
    /// </param>
    public static IServiceCollection AddGatewayDashboard(
        this IServiceCollection services,
        IConfiguration configuration)
    {
        // Dashboard logins delegate bind/search to the shared ZB.MOM.WW.Auth.Ldap
        // provider. Its LdapOptions bind straight from MxGateway:Ldap (the gateway's
        // LdapOptions field names match the shared options: Transport / AllowInsecure /
        // SearchBase / ServiceAccount* / *Attribute). AddZbLdapAuth also adds a
        // ValidateOnStart() so an insecure-transport misconfiguration fails fast at boot.
        services.AddZbLdapAuth(configuration, "MxGateway:Ldap");

        services.AddSingleton<IDashboardSnapshotService, DashboardSnapshotService>();
        services.AddSingleton<IDashboardLiveDataService, DashboardLiveDataService>();
        services.AddSingleton<IDashboardAuthenticator, DashboardAuthenticator>();
        services.AddSingleton<IGroupRoleMapper<string>, DashboardGroupRoleMapper>();
        services.AddSingleton<DashboardApiKeyAuthorization>();
        services.AddSingleton<IDashboardApiKeyManagementService, DashboardApiKeyManagementService>();
        services.AddSingleton<IDashboardSessionAdminService, DashboardSessionAdminService>();
        services.AddSingleton<HubTokenService>();
        services.AddScoped<Hubs.DashboardHubConnectionFactory>();
        services.AddScoped<IDashboardBrowseService, DashboardBrowseService>();
        services.AddSingleton<Hubs.IDashboardEventBroadcaster, Hubs.DashboardEventBroadcaster>();
        services.AddHostedService<Hubs.DashboardSnapshotPublisher>();
        services.AddHostedService<Hubs.AlarmsHubPublisher>();
        services.AddHttpContextAccessor();
        services.AddSingleton<IAuditActorAccessor, HttpAuditActorAccessor>();
        services.AddAntiforgery();
        services.AddCascadingAuthenticationState();
        services.AddRazorComponents()
            .AddInteractiveServerComponents();
        services.AddSignalR();

        services
            .AddAuthentication(DashboardAuthenticationDefaults.AuthenticationScheme)
            .AddCookie(DashboardAuthenticationDefaults.AuthenticationScheme, cookieOptions =>
            {
                // Hardened defaults (HttpOnly, SameSite=Strict, SecurePolicy, SlidingExpiration,
                // ExpireTimeSpan) via the shared ZbCookieDefaults.Apply. requireHttps is set to
                // its default (true / Always) here and overridden per-environment by the
                // PostConfigure below; the 8-hour idle timeout is preserved (not the 30-min default).
                ZbCookieDefaults.Apply(cookieOptions, requireHttps: true, idleTimeout: TimeSpan.FromHours(8));
                // Cookie name, path, and redirect paths are MxGateway-specific — set after Apply
                // so they are never overwritten by the shared helper (Apply intentionally skips name).
                // This is the canonical default; it is overridden per-environment from
                // DashboardOptions.CookieName by the PostConfigure below.
                cookieOptions.Cookie.Name = DashboardAuthenticationDefaults.CookieName;
                cookieOptions.Cookie.Path = "/";
                cookieOptions.LoginPath = "/login";
                cookieOptions.LogoutPath = "/logout";
                cookieOptions.AccessDeniedPath = "/denied";
            })
            .AddScheme<AuthenticationSchemeOptions, HubTokenAuthenticationHandler>(
                DashboardAuthenticationDefaults.HubAuthenticationScheme,
                _ => { });

        // Honour DashboardOptions.RequireHttpsCookie (default true / Always; set false for dev
        // HTTP deployments → SameAsRequest) and the optional per-environment cookie-name
        // override. Both run after the inline AddCookie config above, so they win.
        services.AddOptions<CookieAuthenticationOptions>(DashboardAuthenticationDefaults.AuthenticationScheme)
            .Configure<IOptions<GatewayOptions>>((cookieOptions, gatewayOptions) =>
            {
                cookieOptions.Cookie.SecurePolicy = gatewayOptions.Value.Dashboard.RequireHttpsCookie
                    ? CookieSecurePolicy.Always
                    : CookieSecurePolicy.SameAsRequest;

                // Config-driven cookie name (MxGateway:Dashboard:CookieName). Null/blank keeps
                // the canonical default set above, so a misconfiguration cannot unname the cookie.
                var cookieName = gatewayOptions.Value.Dashboard.CookieName;
                if (!string.IsNullOrWhiteSpace(cookieName))
                {
                    cookieOptions.Cookie.Name = cookieName;
                }
            });

        services.AddAuthorization(authorization =>
        {
            authorization.AddPolicy(
                DashboardAuthenticationDefaults.ViewerPolicy,
                policy => policy.AddRequirements(DashboardAuthorizationRequirement.AnyDashboardRole));
            authorization.AddPolicy(
                DashboardAuthenticationDefaults.AdminPolicy,
                policy => policy.AddRequirements(DashboardAuthorizationRequirement.AdminOnly));
            authorization.AddPolicy(
                DashboardAuthenticationDefaults.HubClientsPolicy,
                policy => policy
                    .AddAuthenticationSchemes(
                        DashboardAuthenticationDefaults.AuthenticationScheme,
                        DashboardAuthenticationDefaults.HubAuthenticationScheme)
                    .AddRequirements(DashboardAuthorizationRequirement.AnyDashboardRole));
        });
        services.AddSingleton<IAuthorizationHandler, DashboardAuthorizationHandler>();

        return services;
    }
}