# Implementações Futuras - Sistema Middleware e Guard

Este documento detalha implementações futuras e conceitos avançados para evolução do sistema de middleware e Guard do OfficeGest, incluindo a implementação do ApplicationGuard e outros sistemas avançados.

## 📋 Índice

1. [ApplicationGuard - Visão Geral](#applicationguard---visão-geral)
2. [Sistema de Multi-Tenancy](#sistema-de-multi-tenancy)
3. [Autenticação Federada](#autenticação-federada)
4. [Microservices Guard](#microservices-guard)
5. [AI-Powered Security](#ai-powered-security)
6. [Zero Trust Architecture](#zero-trust-architecture)
7. [Blockchain Authentication](#blockchain-authentication)

## 🏢 ApplicationGuard - Visão Geral

O **ApplicationGuard** é um sistema de autenticação baseado em aplicações que permite controlar o acesso não apenas por usuário, mas por aplicação empresarial, oferecendo um nível adicional de segurança e controle granular.

### Conceitos Fundamentais

#### Application-Based Authentication
```php
<?php
namespace Og\Modules\Common\Guard\Future;

/**
 * ApplicationGuard - Sistema de autenticação baseado em aplicações
 * 
 * Permite que diferentes aplicações (móveis, web, integrações) tenham
 * seus próprios tokens e permissões, independentemente dos usuários.
 */
class ApplicationGuard implements GuardInterface
{
    private ApplicationManager $applicationManager;
    private ApplicationTokenManager $tokenManager;
    private ModuleAccessManager $moduleManager;
    private LicenseValidator $licenseValidator;
    
    public function __construct(
        ApplicationManager $applicationManager,
        ApplicationTokenManager $tokenManager,
        ModuleAccessManager $moduleManager,
        LicenseValidator $licenseValidator
    ) {
        $this->applicationManager = $applicationManager;
        $this->tokenManager = $tokenManager;
        $this->moduleManager = $moduleManager;
        $this->licenseValidator = $licenseValidator;
    }
    
    /**
     * Autenticar aplicação e usuário em contexto
     */
    public function authenticate(Request $request): ApplicationContext
    {
        // 1. Extrair tokens
        $appToken = $this->extractApplicationToken($request);
        $userToken = $this->extractUserToken($request);
        
        // 2. Validar aplicação
        $application = $this->validateApplication($appToken);
        if (!$application) {
            throw new InvalidApplicationException('Invalid application token');
        }
        
        // 3. Verificar licença da aplicação
        $this->validateApplicationLicense($application);
        
        // 4. Autenticar usuário (opcional)
        $user = null;
        if ($userToken) {
            $user = $this->authenticateUser($userToken, $application);
        }
        
        // 5. Resolver contexto
        return $this->buildApplicationContext($application, $user, $request);
    }
    
    /**
     * Criar contexto completo da aplicação
     */
    private function buildApplicationContext(
        Application $application,
        ?User $user,
        Request $request
    ): ApplicationContext {
        return new ApplicationContext([
            'application' => $application,
            'user' => $user,
            'modules' => $this->resolveAvailableModules($application, $user),
            'permissions' => $this->resolvePermissions($application, $user),
            'features' => $this->resolveFeatures($application, $user),
            'limits' => $this->resolveLimits($application, $user),
            'environment' => $this->resolveEnvironment($application, $request)
        ]);
    }
    
    /**
     * Resolver módulos disponíveis baseado em licença e usuário
     */
    private function resolveAvailableModules(Application $application, ?User $user): array
    {
        // Módulos licenciados para a aplicação
        $licensedModules = $this->licenseValidator->getLicensedModules($application);
        
        // Módulos que o usuário tem acesso (se autenticado)
        $userModules = $user ? $this->moduleManager->getUserModules($user, $application) : [];
        
        // Interseção: apenas módulos que estão licenciados E o usuário tem acesso
        return $user ? array_intersect($licensedModules, $userModules) : $licensedModules;
    }
    
    /**
     * Resolver permissões combinadas da aplicação e usuário
     */
    private function resolvePermissions(Application $application, ?User $user): array
    {
        $permissions = [];
        
        // Permissões base da aplicação
        $permissions = array_merge($permissions, $application->getBasePermissions());
        
        // Permissões específicas do usuário na aplicação
        if ($user) {
            $userPermissions = $user->getApplicationPermissions($application->getId());
            $permissions = array_merge($permissions, $userPermissions);
        }
        
        // Aplicar filtros de segurança
        return $this->applySecurityFilters($permissions, $application, $user);
    }
}

/**
 * Contexto de aplicação com informações completas
 */
class ApplicationContext
{
    private array $data;
    private array $cache = [];
    
    public function __construct(array $data)
    {
        $this->data = $data;
    }
    
    // Getters básicos
    public function getApplication(): Application { return $this->data['application']; }
    public function getUser(): ?User { return $this->data['user'] ?? null; }
    public function isUserAuthenticated(): bool { return $this->getUser() !== null; }
    
    // Verificações de acesso
    public function hasModule(string $module): bool
    {
        return $this->isCached("module_{$module}") ?: 
               $this->cache("module_{$module}", in_array(strtoupper($module), $this->data['modules']));
    }
    
    public function hasPermission(string $permission): bool
    {
        return $this->isCached("permission_{$permission}") ?:
               $this->cache("permission_{$permission}", $this->checkPermission($permission));
    }
    
    public function hasFeature(string $feature): bool
    {
        return in_array($feature, $this->data['features']);
    }
    
    // Verificações avançadas
    public function canAccessModule(string $module, array $context = []): bool
    {
        if (!$this->hasModule($module)) {
            return false;
        }
        
        // Verificar limites específicos do módulo
        if (!$this->isWithinModuleLimits($module, $context)) {
            return false;
        }
        
        // Verificar condições temporais
        if (!$this->isWithinTimeRestrictions($module)) {
            return false;
        }
        
        return true;
    }
    
    public function getRemainingApiCalls(): int
    {
        $limits = $this->data['limits'];
        $usage = $this->getCurrentUsage();
        
        return max(0, $limits['api_calls_per_day'] - $usage['api_calls_today']);
    }
    
    // Métodos auxiliares
    private function checkPermission(string $permission): bool
    {
        $permissions = $this->data['permissions'];
        
        // Verificar permissão exata
        if (in_array($permission, $permissions)) {
            return true;
        }
        
        // Verificar wildcards
        foreach ($permissions as $p) {
            if ($this->matchesWildcard($p, $permission)) {
                return true;
            }
        }
        
        return false;
    }
    
    private function matchesWildcard(string $pattern, string $permission): bool
    {
        if (!str_contains($pattern, '*')) {
            return false;
        }
        
        $regex = '/^' . str_replace('*', '.*', preg_quote($pattern, '/')) . '$/';
        return preg_match($regex, $permission);
    }
    
    private function cache(string $key, $value)
    {
        $this->cache[$key] = $value;
        return $value;
    }
    
    private function isCached(string $key): bool
    {
        return array_key_exists($key, $this->cache);
    }
}
```

### Middleware ApplicationGuard

```php
<?php
namespace Og\Modules\Common\Guard\Future\Middleware;

class ApplicationGuardMiddleware implements MiddlewareInterface
{
    private ApplicationGuard $applicationGuard;
    
    public function handle(Request $request, Closure $next, ...$requirements): mixed
    {
        try {
            // Autenticar e obter contexto da aplicação
            $context = $this->applicationGuard->authenticate($request);
            
            // Validar requisitos se especificados
            if (!empty($requirements)) {
                $this->validateRequirements($context, $requirements);
            }
            
            // Adicionar contexto ao request
            $request->attributes->set('app_context', $context);
            
            // Log da autenticação
            $this->logAuthentication($context, $request);
            
            return $next($request);
            
        } catch (ApplicationGuardException $e) {
            return $this->handleAuthenticationFailure($e, $request);
        }
    }
    
    private function validateRequirements(ApplicationContext $context, array $requirements): void
    {
        foreach ($requirements as $requirement) {
            [$type, $value] = $this->parseRequirement($requirement);
            
            switch ($type) {
                case 'module':
                    if (!$context->hasModule($value)) {
                        throw new ModuleNotAvailableException("Module '{$value}' not available");
                    }
                    break;
                    
                case 'permission':
                    if (!$context->hasPermission($value)) {
                        throw new InsufficientPermissionsException("Permission '{$value}' required");
                    }
                    break;
                    
                case 'feature':
                    if (!$context->hasFeature($value)) {
                        throw new FeatureNotAvailableException("Feature '{$value}' not available");
                    }
                    break;
                    
                case 'user':
                    if (!$context->isUserAuthenticated()) {
                        throw new UserAuthenticationRequiredException('User authentication required');
                    }
                    break;
            }
        }
    }
    
    private function parseRequirement(string $requirement): array
    {
        if (str_contains($requirement, ':')) {
            return explode(':', $requirement, 2);
        }
        
        // Default é módulo se não especificado
        return ['module', $requirement];
    }
}
```

### Uso Prático do ApplicationGuard

```php
// Configuração de aplicações
$applications = [
    'mobile_app' => [
        'name' => 'OfficeGest Mobile',
        'type' => 'mobile',
        'licensed_modules' => ['VENDAS', 'WMSO', 'CRM'],
        'base_permissions' => ['mobile:*', 'offline:sync'],
        'limits' => [
            'api_calls_per_day' => 10000,
            'concurrent_users' => 50
        ]
    ],
    'web_portal' => [
        'name' => 'Portal Web',
        'type' => 'web',
        'licensed_modules' => ['VENDAS', 'WMSO', 'FINANCEIRO', 'RH', 'CRM'],
        'base_permissions' => ['web:*', 'reports:*'],
        'limits' => [
            'api_calls_per_day' => 50000,
            'concurrent_users' => 200
        ]
    ],
    'integration_api' => [
        'name' => 'API de Integração',
        'type' => 'api',
        'licensed_modules' => ['VENDAS', 'WMSO', 'FINANCEIRO'],
        'base_permissions' => ['api:read', 'api:write', 'integration:*'],
        'limits' => [
            'api_calls_per_day' => 100000,
            'concurrent_requests' => 100
        ]
    ]
];

// Rotas com ApplicationGuard
Route::group([
    'prefix' => 'api/mobile',
    'middleware' => 'application_guard:module:vendas,module:wmso,user'
], function() {
    Route::get('/vendas/sync', [MobileSyncController::class, 'syncVendas']);
    Route::post('/vendas/offline', [MobileSyncController::class, 'uploadOfflineVendas']);
});

Route::group([
    'prefix' => 'api/integration',
    'middleware' => 'application_guard:permission:integration:read'
], function() {
    Route::get('/export/vendas', [IntegrationController::class, 'exportVendas']);
    Route::get('/export/stocks', [IntegrationController::class, 'exportStocks']);
});
```

## 🏗️ Sistema de Multi-Tenancy

```php
<?php
namespace Og\Modules\Common\Guard\Future\MultiTenant;

/**
 * Sistema de multi-tenancy para SaaS
 */
class MultiTenantGuard extends ApplicationGuard
{
    private TenantResolver $tenantResolver;
    private TenantManager $tenantManager;
    
    public function authenticate(Request $request): TenantApplicationContext
    {
        // 1. Resolver tenant
        $tenant = $this->tenantResolver->resolve($request);
        if (!$tenant) {
            throw new TenantNotFoundException('Tenant not found or inactive');
        }
        
        // 2. Configurar contexto do tenant
        $this->configureForTenant($tenant);
        
        // 3. Autenticação normal da aplicação
        $appContext = parent::authenticate($request);
        
        // 4. Criar contexto multi-tenant
        return new TenantApplicationContext($appContext, $tenant);
    }
    
    private function configureForTenant(Tenant $tenant): void
    {
        // Trocar conexão do banco de dados
        $this->switchDatabaseConnection($tenant);
        
        // Configurar cache específico do tenant
        $this->configureTenantCache($tenant);
        
        // Aplicar configurações específicas
        $this->applyTenantConfiguration($tenant);
    }
    
    private function switchDatabaseConnection(Tenant $tenant): void
    {
        $config = [
            'host' => $tenant->getDatabaseHost(),
            'database' => $tenant->getDatabaseName(),
            'username' => $tenant->getDatabaseUser(),
            'password' => $tenant->getDatabasePassword(),
            'prefix' => $tenant->getTablePrefix()
        ];
        
        DatabaseManager::setTenantConnection($tenant->getId(), $config);
        DatabaseManager::setDefaultConnection($tenant->getId());
    }
}

class TenantApplicationContext extends ApplicationContext
{
    private Tenant $tenant;
    
    public function __construct(ApplicationContext $appContext, Tenant $tenant)
    {
        parent::__construct($appContext->toArray());
        $this->tenant = $tenant;
    }
    
    public function getTenant(): Tenant { return $this->tenant; }
    
    public function hasFeatureForTenant(string $feature): bool
    {
        // Verificar se o tenant tem acesso ao feature
        if (!$this->tenant->hasFeature($feature)) {
            return false;
        }
        
        return $this->hasFeature($feature);
    }
    
    public function getDataWithTenantScope(): array
    {
        $data = parent::getData();
        $data['tenant'] = $this->tenant->toArray();
        return $data;
    }
}

class TenantResolver
{
    public function resolve(Request $request): ?Tenant
    {
        // Tentativas de resolução por ordem de prioridade
        
        // 1. Por header específico
        if ($tenant = $this->resolveByHeader($request)) {
            return $tenant;
        }
        
        // 2. Por subdomain
        if ($tenant = $this->resolveBySubdomain($request)) {
            return $tenant;
        }
        
        // 3. Por domínio customizado
        if ($tenant = $this->resolveByCustomDomain($request)) {
            return $tenant;
        }
        
        // 4. Por path prefix
        if ($tenant = $this->resolveByPathPrefix($request)) {
            return $tenant;
        }
        
        return null;
    }
    
    private function resolveBySubdomain(Request $request): ?Tenant
    {
        $host = $request->getHost();
        $parts = explode('.', $host);
        
        if (count($parts) >= 3) {
            $subdomain = $parts[0];
            return Tenant::findBySlug($subdomain);
        }
        
        return null;
    }
    
    private function resolveByCustomDomain(Request $request): ?Tenant
    {
        $host = $request->getHost();
        return Tenant::findByCustomDomain($host);
    }
}
```

## 🌐 Autenticação Federada

```php
<?php
namespace Og\Modules\Common\Guard\Future\Federation;

/**
 * Sistema de autenticação federada (SSO)
 */
class FederatedGuard extends ApplicationGuard
{
    private array $identityProviders = [];
    private SamlHandler $samlHandler;
    private OAuthHandler $oauthHandler;
    private OpenIDConnectHandler $oidcHandler;
    
    public function authenticateWithProvider(string $provider, array $credentials): ?FederatedUser
    {
        if (!isset($this->identityProviders[$provider])) {
            throw new UnknownIdentityProviderException("Provider '{$provider}' not configured");
        }
        
        $providerConfig = $this->identityProviders[$provider];
        
        switch ($providerConfig['type']) {
            case 'saml':
                return $this->authenticateWithSaml($providerConfig, $credentials);
            case 'oauth':
                return $this->authenticateWithOAuth($providerConfig, $credentials);
            case 'openid_connect':
                return $this->authenticateWithOIDC($providerConfig, $credentials);
            case 'ldap':
                return $this->authenticateWithLdap($providerConfig, $credentials);
            default:
                throw new UnsupportedProviderTypeException("Provider type '{$providerConfig['type']}' not supported");
        }
    }
    
    private function authenticateWithSaml(array $config, array $credentials): ?FederatedUser
    {
        $assertion = $this->samlHandler->validateAssertion($credentials['saml_response'], $config);
        
        if (!$assertion) {
            return null;
        }
        
        // Mapear atributos SAML para usuário local
        $userData = $this->mapSamlAttributes($assertion, $config['attribute_mapping']);
        
        // Criar ou atualizar usuário local
        $localUser = $this->findOrCreateLocalUser($userData, 'saml', $config['provider_id']);
        
        return new FederatedUser($localUser, $assertion, 'saml');
    }
    
    private function authenticateWithOIDC(array $config, array $credentials): ?FederatedUser
    {
        // Validar JWT token
        $idToken = $this->oidcHandler->validateIdToken($credentials['id_token'], $config);
        
        if (!$idToken) {
            return null;
        }
        
        // Extrair claims do token
        $claims = $idToken->getClaims();
        
        // Mapear claims para usuário local
        $userData = $this->mapOidcClaims($claims, $config['claim_mapping']);
        
        $localUser = $this->findOrCreateLocalUser($userData, 'oidc', $config['provider_id']);
        
        return new FederatedUser($localUser, $claims, 'oidc');
    }
    
    private function findOrCreateLocalUser(array $userData, string $providerType, string $providerId): User
    {
        // Procurar usuário existente por identificador federado
        $federatedIdentity = FederatedIdentity::where([
            'provider_type' => $providerType,
            'provider_id' => $providerId,
            'provider_user_id' => $userData['external_id']
        ])->first();
        
        if ($federatedIdentity) {
            $user = User::find($federatedIdentity->user_id);
            
            // Atualizar dados do usuário se necessário
            $this->updateUserFromFederatedData($user, $userData);
            
            return $user;
        }
        
        // Tentar encontrar por email
        $existingUser = User::where('email', $userData['email'])->first();
        
        if ($existingUser) {
            // Vincular identidade federada ao usuário existente
            $this->linkFederatedIdentity($existingUser, $providerType, $providerId, $userData['external_id']);
            return $existingUser;
        }
        
        // Criar novo usuário
        return $this->createFederatedUser($userData, $providerType, $providerId);
    }
}

class FederatedUser extends User
{
    private array $federatedData;
    private string $providerType;
    
    public function __construct(User $localUser, array $federatedData, string $providerType)
    {
        parent::__construct($localUser->toArray());
        $this->federatedData = $federatedData;
        $this->providerType = $providerType;
    }
    
    public function getFederatedData(): array { return $this->federatedData; }
    public function getProviderType(): string { return $this->providerType; }
    
    public function getFederatedClaim(string $claim, $default = null)
    {
        return $this->federatedData[$claim] ?? $default;
    }
    
    public function isFederated(): bool { return true; }
}

// Middleware para autenticação federada
class FederatedAuthMiddleware implements MiddlewareInterface
{
    private FederatedGuard $federatedGuard;
    
    public function handle(Request $request, Closure $next, string $provider = null): mixed
    {
        if ($provider) {
            // Forçar autenticação com provider específico
            $this->requireProviderAuthentication($request, $provider);
        }
        
        // Verificar se já está autenticado via federação
        $user = $this->federatedGuard->user();
        
        if (!$user || !$user->isFederated()) {
            return $this->redirectToSsoProvider($request, $provider);
        }
        
        return $next($request);
    }
    
    private function redirectToSsoProvider(Request $request, ?string $provider): Response
    {
        $ssoUrl = $this->buildSsoUrl($provider, $request->getUri());
        
        return Response::redirect($ssoUrl);
    }
}
```

## 🔧 Microservices Guard

```php
<?php
namespace Og\Modules\Common\Guard\Future\Microservices;

/**
 * Guard para arquitetura de microserviços
 */
class MicroservicesGuard
{
    private ServiceRegistry $serviceRegistry;
    private JwtTokenHandler $jwtHandler;
    private ServiceMeshClient $serviceMesh;
    
    public function authenticateServiceToService(Request $request): ServiceContext
    {
        // Extrair JWT de serviço para serviço
        $serviceToken = $this->extractServiceToken($request);
        
        if (!$serviceToken) {
            throw new MissingServiceTokenException();
        }
        
        // Validar token
        $claims = $this->jwtHandler->validateServiceToken($serviceToken);
        
        // Verificar se serviço está registrado
        $sourceService = $this->serviceRegistry->getService($claims['service_id']);
        if (!$sourceService) {
            throw new UnknownServiceException();
        }
        
        // Verificar permissões de serviço para serviço
        $targetService = $this->resolveTargetService($request);
        if (!$this->hasServicePermission($sourceService, $targetService, $claims['permissions'])) {
            throw new ServicePermissionDeniedException();
        }
        
        return new ServiceContext($sourceService, $targetService, $claims);
    }
    
    public function createServiceToken(string $serviceId, array $permissions, int $ttl = 3600): string
    {
        $claims = [
            'iss' => 'officegest-service-mesh',
            'aud' => 'officegest-services',
            'service_id' => $serviceId,
            'permissions' => $permissions,
            'iat' => time(),
            'exp' => time() + $ttl,
            'jti' => uniqid('service_token_', true)
        ];
        
        return $this->jwtHandler->createServiceToken($claims);
    }
    
    public function authenticateUserThroughGateway(Request $request): ?UserServiceContext
    {
        // Token do usuário via API Gateway
        $userToken = $this->extractUserToken($request);
        
        // Token do serviço (injetado pelo gateway)
        $serviceToken = $this->extractServiceToken($request);
        
        // Validar ambos os tokens
        $userClaims = $this->jwtHandler->validateUserToken($userToken);
        $serviceClaims = $this->jwtHandler->validateServiceToken($serviceToken);
        
        // Verificar se o serviço pode atuar em nome do usuário
        if (!$this->serviceCanActOnBehalfOfUser($serviceClaims, $userClaims)) {
            throw new ServiceUserPermissionException();
        }
        
        // Resolver usuário
        $user = $this->resolveUser($userClaims['user_id']);
        
        return new UserServiceContext($user, $serviceClaims, $userClaims);
    }
}

class ServiceMeshMiddleware implements MiddlewareInterface
{
    private MicroservicesGuard $microservicesGuard;
    private CircuitBreaker $circuitBreaker;
    private RateLimiter $rateLimiter;
    
    public function handle(Request $request, Closure $next, string $requiredPermission = null): mixed
    {
        // Verificar se é request interno (serviço para serviço)
        if ($this->isInternalServiceRequest($request)) {
            $context = $this->microservicesGuard->authenticateServiceToService($request);
            
            if ($requiredPermission && !$context->hasPermission($requiredPermission)) {
                throw new InsufficientServicePermissionException();
            }
            
            $request->attributes->set('service_context', $context);
        } else {
            // Request externo via Gateway
            $context = $this->microservicesGuard->authenticateUserThroughGateway($request);
            $request->attributes->set('user_service_context', $context);
        }
        
        // Aplicar rate limiting por serviço
        $this->applyServiceRateLimit($request);
        
        // Circuit breaker para serviços downstream
        return $this->circuitBreaker->execute(function() use ($request, $next) {
            return $next($request);
        });
    }
    
    private function isInternalServiceRequest(Request $request): bool
    {
        // Verificar se request vem de dentro da service mesh
        $sourceService = $request->header('X-Service-Source');
        $serviceMeshToken = $request->header('X-Service-Mesh-Token');
        
        return $sourceService && $serviceMeshToken;
    }
}
```

## 🤖 AI-Powered Security

```php
<?php
namespace Og\Modules\Common\Guard\Future\AI;

/**
 * Sistema de segurança baseado em IA
 */
class AISecurityGuard extends ApplicationGuard
{
    private BehaviorAnalyzer $behaviorAnalyzer;
    private AnomalyDetector $anomalyDetector;
    private RiskScorer $riskScorer;
    private MLModelManager $mlModelManager;
    
    public function authenticate(Request $request): AIEnhancedContext
    {
        // Autenticação padrão
        $context = parent::authenticate($request);
        
        // Análise comportamental em tempo real
        $behaviorScore = $this->analyzeBehavior($context, $request);
        
        // Detecção de anomalias
        $anomalies = $this->detectAnomalies($context, $request);
        
        // Cálculo do score de risco
        $riskScore = $this->calculateRiskScore($context, $behaviorScore, $anomalies);
        
        // Ações baseadas no risco
        $this->handleRiskBasedActions($riskScore, $context, $request);
        
        return new AIEnhancedContext($context, [
            'behavior_score' => $behaviorScore,
            'anomalies' => $anomalies,
            'risk_score' => $riskScore,
            'ai_recommendations' => $this->generateRecommendations($riskScore, $anomalies)
        ]);
    }
    
    private function analyzeBehavior(ApplicationContext $context, Request $request): float
    {
        $behaviorFeatures = [
            'time_of_day' => date('H'),
            'day_of_week' => date('N'),
            'ip_geolocation' => $this->getIpGeolocation($request->getClientIp()),
            'user_agent' => $request->header('User-Agent'),
            'request_frequency' => $this->getRequestFrequency($context->getUser()),
            'typical_endpoints' => $this->getTypicalEndpoints($context->getUser()),
            'session_duration' => $this->getSessionDuration($context->getUser()),
            'device_fingerprint' => $this->getDeviceFingerprint($request)
        ];
        
        return $this->behaviorAnalyzer->analyze($behaviorFeatures);
    }
    
    private function detectAnomalies(ApplicationContext $context, Request $request): array
    {
        $anomalies = [];
        
        // Anomalias de localização
        if ($locationAnomaly = $this->detectLocationAnomaly($context, $request)) {
            $anomalies[] = $locationAnomaly;
        }
        
        // Anomalias de tempo
        if ($timeAnomaly = $this->detectTimeAnomaly($context, $request)) {
            $anomalies[] = $timeAnomaly;
        }
        
        // Anomalias de comportamento
        if ($behaviorAnomaly = $this->detectBehaviorAnomaly($context, $request)) {
            $anomalies[] = $behaviorAnomaly;
        }
        
        // Anomalias de device
        if ($deviceAnomaly = $this->detectDeviceAnomaly($context, $request)) {
            $anomalies[] = $deviceAnomaly;
        }
        
        return $anomalies;
    }
    
    private function calculateRiskScore(
        ApplicationContext $context, 
        float $behaviorScore, 
        array $anomalies
    ): float {
        $baseRisk = 0.1; // Risco base
        
        // Fator comportamental (0.0 a 1.0)
        $behaviorRisk = 1 - $behaviorScore;
        
        // Fator de anomalias
        $anomalyRisk = min(1.0, count($anomalies) * 0.2);
        
        // Fatores contextuais
        $contextualFactors = [
            'is_admin' => $context->hasPermission('admin') ? 0.1 : 0,
            'sensitive_operation' => $this->isSensitiveOperation($context) ? 0.3 : 0,
            'new_device' => $this->isNewDevice($context) ? 0.2 : 0,
            'off_hours' => $this->isOffHours() ? 0.1 : 0
        ];
        
        $contextualRisk = array_sum($contextualFactors);
        
        // Score final (0.0 a 1.0)
        return min(1.0, $baseRisk + $behaviorRisk * 0.4 + $anomalyRisk * 0.3 + $contextualRisk * 0.3);
    }
    
    private function handleRiskBasedActions(float $riskScore, ApplicationContext $context, Request $request): void
    {
        if ($riskScore >= 0.9) {
            // Risco muito alto - bloquear imediatamente
            $this->blockUser($context->getUser(), 'High risk score: ' . $riskScore);
            throw new HighRiskBlockedException('Access blocked due to high risk score');
            
        } elseif ($riskScore >= 0.7) {
            // Risco alto - exigir MFA adicional
            $this->requireAdditionalMFA($context, $request);
            
        } elseif ($riskScore >= 0.5) {
            // Risco médio - aumentar monitoring
            $this->increaseMonitoring($context, $request);
            
        } elseif ($riskScore >= 0.3) {
            // Risco baixo-médio - log para análise
            $this->logForAnalysis($context, $request, $riskScore);
        }
    }
}

class AIEnhancedContext extends ApplicationContext
{
    private array $aiData;
    
    public function __construct(ApplicationContext $baseContext, array $aiData)
    {
        parent::__construct($baseContext->toArray());
        $this->aiData = $aiData;
    }
    
    public function getRiskScore(): float
    {
        return $this->aiData['risk_score'];
    }
    
    public function getBehaviorScore(): float
    {
        return $this->aiData['behavior_score'];
    }
    
    public function getAnomalies(): array
    {
        return $this->aiData['anomalies'];
    }
    
    public function isHighRisk(): bool
    {
        return $this->getRiskScore() >= 0.7;
    }
    
    public function requiresAdditionalVerification(): bool
    {
        return $this->getRiskScore() >= 0.5;
    }
    
    public function getAIRecommendations(): array
    {
        return $this->aiData['ai_recommendations'];
    }
}
```

## 🔒 Zero Trust Architecture

```php
<?php
namespace Og\Modules\Common\Guard\Future\ZeroTrust;

/**
 * Implementação de Zero Trust Security
 */
class ZeroTrustGuard extends ApplicationGuard
{
    private PolicyEngine $policyEngine;
    private ContinuousVerification $continuousVerification;
    private TrustScorer $trustScorer;
    private NetworkAnalyzer $networkAnalyzer;
    
    public function authenticate(Request $request): ZeroTrustContext
    {
        // 1. Autenticação base
        $context = parent::authenticate($request);
        
        // 2. Verificação contínua de identidade
        $identityTrust = $this->continuousVerification->verifyIdentity($context, $request);
        
        // 3. Análise de device/endpoint
        $deviceTrust = $this->verifyDevice($request);
        
        // 4. Análise de rede
        $networkTrust = $this->networkAnalyzer->analyzeTrust($request);
        
        // 5. Avaliação de políticas
        $policyCompliance = $this->policyEngine->evaluate($context, $request);
        
        // 6. Cálculo do trust score
        $trustScore = $this->trustScorer->calculate([
            'identity' => $identityTrust,
            'device' => $deviceTrust,
            'network' => $networkTrust,
            'policy' => $policyCompliance,
            'behavior' => $this->getBehaviorTrust($context, $request)
        ]);
        
        // 7. Aplicar ações baseadas no trust score
        $this->applyZeroTrustActions($trustScore, $context, $request);
        
        return new ZeroTrustContext($context, [
            'trust_score' => $trustScore,
            'identity_trust' => $identityTrust,
            'device_trust' => $deviceTrust,
            'network_trust' => $networkTrust,
            'policy_compliance' => $policyCompliance
        ]);
    }
    
    private function verifyDevice(Request $request): DeviceTrustScore
    {
        $deviceFingerprint = $this->generateDeviceFingerprint($request);
        
        // Verificar se device é conhecido
        $knownDevice = $this->deviceRegistry->findDevice($deviceFingerprint);
        
        $trustFactors = [
            'is_registered' => $knownDevice ? 1.0 : 0.0,
            'security_posture' => $this->assessDeviceSecurityPosture($request),
            'compliance_status' => $this->checkDeviceCompliance($deviceFingerprint),
            'anomaly_score' => $this->detectDeviceAnomalies($deviceFingerprint, $request)
        ];
        
        return new DeviceTrustScore($trustFactors);
    }
    
    private function applyZeroTrustActions(TrustScore $trustScore, ApplicationContext $context, Request $request): void
    {
        $score = $trustScore->getOverallScore();
        
        if ($score < 0.3) {
            // Trust score muito baixo - bloquear acesso
            throw new ZeroTrustAccessDeniedException('Access denied due to low trust score');
            
        } elseif ($score < 0.5) {
            // Trust score baixo - acesso limitado
            $this->applyRestrictedAccess($context, $trustScore);
            
        } elseif ($score < 0.7) {
            // Trust score médio - verificação adicional
            $this->requireAdditionalVerification($context, $request);
            
        } elseif ($score < 0.9) {
            // Trust score alto - acesso normal com monitoring
            $this->enableEnhancedMonitoring($context, $request);
        }
        
        // Sempre aplicar least privilege
        $this->applyLeastPrivilege($context, $trustScore);
    }
    
    private function applyLeastPrivilege(ApplicationContext $context, TrustScore $trustScore): void
    {
        // Reduzir permissões baseado no trust score
        $permissions = $context->getPermissions();
        $trustLevel = $trustScore->getOverallScore();
        
        if ($trustLevel < 0.8) {
            // Remover permissões sensíveis
            $permissions = array_filter($permissions, function($permission) {
                return !$this->isSensitivePermission($permission);
            });
        }
        
        if ($trustLevel < 0.6) {
            // Apenas permissões básicas
            $permissions = array_filter($permissions, function($permission) {
                return $this->isBasicPermission($permission);
            });
        }
        
        $context->setPermissions($permissions);
    }
}

class ZeroTrustContext extends ApplicationContext
{
    private array $trustData;
    
    public function __construct(ApplicationContext $baseContext, array $trustData)
    {
        parent::__construct($baseContext->toArray());
        $this->trustData = $trustData;
    }
    
    public function getTrustScore(): TrustScore
    {
        return $this->trustData['trust_score'];
    }
    
    public function isTrusted(): bool
    {
        return $this->getTrustScore()->getOverallScore() >= 0.7;
    }
    
    public function hasHighTrust(): bool
    {
        return $this->getTrustScore()->getOverallScore() >= 0.9;
    }
    
    public function requiresContinuousVerification(): bool
    {
        return $this->getTrustScore()->getOverallScore() < 0.8;
    }
    
    public function getDeviceTrust(): DeviceTrustScore
    {
        return $this->trustData['device_trust'];
    }
    
    public function getNetworkTrust(): NetworkTrustScore
    {
        return $this->trustData['network_trust'];
    }
}

// Middleware Zero Trust
class ZeroTrustMiddleware implements MiddlewareInterface
{
    private ZeroTrustGuard $zeroTrustGuard;
    
    public function handle(Request $request, Closure $next, float $minimumTrust = 0.5): mixed
    {
        $context = $this->zeroTrustGuard->authenticate($request);
        
        if ($context->getTrustScore()->getOverallScore() < $minimumTrust) {
            return Response::json([
                'error' => 'Insufficient Trust Level',
                'message' => 'Access denied due to insufficient trust score',
                'trust_score' => $context->getTrustScore()->getOverallScore(),
                'required_minimum' => $minimumTrust
            ], 403);
        }
        
        $request->attributes->set('zero_trust_context', $context);
        
        // Verificação contínua durante a requisição
        $this->enableContinuousVerification($context, $request);
        
        return $next($request);
    }
}
```

## ⛓️ Blockchain Authentication

```php
<?php
namespace Og\Modules\Common\Guard\Future\Blockchain;

/**
 * Sistema de autenticação baseado em blockchain
 */
class BlockchainGuard extends ApplicationGuard
{
    private BlockchainClient $blockchainClient;
    private SmartContractManager $contractManager;
    private IdentityRegistry $identityRegistry;
    
    public function authenticateWithBlockchain(string $walletAddress, string $signature, string $message): ?BlockchainUser
    {
        // 1. Verificar assinatura digital
        if (!$this->verifyDigitalSignature($walletAddress, $signature, $message)) {
            throw new InvalidSignatureException();
        }
        
        // 2. Verificar se wallet está registrada
        $identity = $this->identityRegistry->getIdentity($walletAddress);
        if (!$identity) {
            throw new UnregisteredWalletException();
        }
        
        // 3. Verificar status na blockchain
        $onChainStatus = $this->blockchainClient->getIdentityStatus($walletAddress);
        if (!$onChainStatus['active']) {
            throw new DeactivatedIdentityException();
        }
        
        // 4. Verificar permissões on-chain
        $permissions = $this->getOnChainPermissions($walletAddress);
        
        // 5. Criar contexto blockchain
        return new BlockchainUser([
            'wallet_address' => $walletAddress,
            'identity' => $identity,
            'permissions' => $permissions,
            'on_chain_status' => $onChainStatus,
            'authentication_method' => 'blockchain'
        ]);
    }
    
    public function createBlockchainToken(string $walletAddress, array $permissions): BlockchainToken
    {
        // Criar token na blockchain
        $tokenData = [
            'wallet_address' => $walletAddress,
            'permissions' => $permissions,
            'issued_at' => time(),
            'expires_at' => time() + 3600 // 1 hora
        ];
        
        $transactionHash = $this->contractManager->issueToken($tokenData);
        
        // Aguardar confirmação
        $this->waitForConfirmation($transactionHash);
        
        return new BlockchainToken($tokenData, $transactionHash);
    }
    
    private function getOnChainPermissions(string $walletAddress): array
    {
        // Consultar smart contract de permissões
        $permissionContract = $this->contractManager->getContract('permissions');
        
        $permissions = $permissionContract->call('getUserPermissions', [$walletAddress]);
        
        // Decodificar permissões do formato blockchain
        return $this->decodeBlockchainPermissions($permissions);
    }
    
    private function verifyDigitalSignature(string $walletAddress, string $signature, string $message): bool
    {
        // Verificar assinatura usando biblioteca de criptografia
        return $this->blockchainClient->verifySignature($walletAddress, $signature, $message);
    }
}

class BlockchainUser extends User
{
    private string $walletAddress;
    private array $onChainData;
    
    public function __construct(array $data)
    {
        $this->walletAddress = $data['wallet_address'];
        $this->onChainData = $data['on_chain_status'];
        
        parent::__construct($data['identity']);
    }
    
    public function getWalletAddress(): string
    {
        return $this->walletAddress;
    }
    
    public function getOnChainData(): array
    {
        return $this->onChainData;
    }
    
    public function hasOnChainPermission(string $permission): bool
    {
        return in_array($permission, $this->getPermissions());
    }
    
    public function getReputationScore(): float
    {
        return $this->onChainData['reputation_score'] ?? 0.0;
    }
}

class BlockchainToken extends PersonalAccessToken
{
    private string $transactionHash;
    private bool $onChain = true;
    
    public function __construct(array $tokenData, string $transactionHash)
    {
        parent::__construct($tokenData);
        $this->transactionHash = $transactionHash;
    }
    
    public function getTransactionHash(): string
    {
        return $this->transactionHash;
    }
    
    public function isOnChain(): bool
    {
        return $this->onChain;
    }
    
    public function revokeOnChain(): bool
    {
        // Revogar token na blockchain
        $contractManager = app(SmartContractManager::class);
        $result = $contractManager->revokeToken($this->getId(), $this->transactionHash);
        
        if ($result) {
            $this->onChain = false;
        }
        
        return $result;
    }
}

// Smart Contract para gerenciamento de identidades (exemplo em Solidity)
/*
pragma solidity ^0.8.0;

contract OfficeGestIdentity {
    struct Identity {
        string userId;
        string[] permissions;
        uint256 createdAt;
        uint256 updatedAt;
        bool active;
        uint256 reputationScore;
    }
    
    mapping(address => Identity) public identities;
    mapping(address => mapping(string => bool)) public permissions;
    
    event IdentityCreated(address indexed wallet, string userId);
    event PermissionGranted(address indexed wallet, string permission);
    event PermissionRevoked(address indexed wallet, string permission);
    
    function createIdentity(string memory userId) public {
        require(bytes(identities[msg.sender].userId).length == 0, "Identity already exists");
        
        identities[msg.sender] = Identity({
            userId: userId,
            permissions: new string[](0),
            createdAt: block.timestamp,
            updatedAt: block.timestamp,
            active: true,
            reputationScore: 100
        });
        
        emit IdentityCreated(msg.sender, userId);
    }
    
    function grantPermission(address wallet, string memory permission) public {
        require(identities[wallet].active, "Identity not active");
        
        permissions[wallet][permission] = true;
        identities[wallet].permissions.push(permission);
        identities[wallet].updatedAt = block.timestamp;
        
        emit PermissionGranted(wallet, permission);
    }
    
    function hasPermission(address wallet, string memory permission) public view returns (bool) {
        return permissions[wallet][permission];
    }
    
    function getUserPermissions(address wallet) public view returns (string[] memory) {
        return identities[wallet].permissions;
    }
}
*/
```

## 📊 Conclusão

Estas implementações futuras representam a evolução natural do sistema de middleware e Guard do OfficeGest, incorporando tecnologias emergentes e padrões de segurança modernos:

1. **ApplicationGuard** - Controle granular por aplicação
2. **Multi-Tenancy** - Suporte para SaaS multi-inquilino
3. **Autenticação Federada** - SSO corporativo
4. **Microservices Guard** - Segurança para arquitetura distribuída
5. **AI-Powered Security** - Segurança inteligente e adaptativa
6. **Zero Trust Architecture** - Segurança sem perímetro
7. **Blockchain Authentication** - Identidade descentralizada

<function_calls>
<invoke name="TodoWrite">
<parameter name="todos">[{"id": "1", "content": "Criar estrutura de documenta\u00e7\u00e3o em _docs/middleware-guard-system/", "status": "completed"}, {"id": "2", "content": "Analisar sistema de middleware existente", "status": "completed"}, {"id": "3", "content": "Analisar sistema Guard existente", "status": "completed"}, {"id": "4", "content": "Documentar middlewares espec\u00edficos (OgModuleMiddleware, etc)", "status": "completed"}, {"id": "5", "content": "Criar exemplos pr\u00e1ticos do ERP com base na codebase", "status": "completed"}, {"id": "6", "content": "Documentar implementa\u00e7\u00f5es futuras (ApplicationGuard)", "status": "completed"}]