/*
 * Copyright (c) 2012, 2020 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.model.internal;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.IdentityHashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeSet;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.stream.Collectors;

import javax.ws.rs.ConstrainedTo;
import javax.ws.rs.Priorities;
import javax.ws.rs.RuntimeType;
import javax.ws.rs.core.Configuration;
import javax.ws.rs.core.Feature;
import javax.ws.rs.core.FeatureContext;

import javax.annotation.Priority;

import org.glassfish.jersey.ExtendedConfig;
import org.glassfish.jersey.internal.LocalizationMessages;
import org.glassfish.jersey.internal.ServiceFinder;
import org.glassfish.jersey.internal.inject.Binder;
import org.glassfish.jersey.internal.inject.CompositeBinder;
import org.glassfish.jersey.internal.inject.InjectionManager;
import org.glassfish.jersey.internal.inject.ProviderBinder;
import org.glassfish.jersey.internal.spi.AutoDiscoverable;
import org.glassfish.jersey.internal.spi.ForcedAutoDiscoverable;
import org.glassfish.jersey.internal.util.PropertiesHelper;
import org.glassfish.jersey.model.ContractProvider;
import org.glassfish.jersey.process.Inflector;

Common immutable Configuration implementation for server and client. 
Author:
Michal Gajdos, Marek Potociar/**
 * Common immutable {@link javax.ws.rs.core.Configuration} implementation for
 * server and client.
 *
 * @author Michal Gajdos
 * @author Marek Potociar
 */
public class CommonConfig implements FeatureContext, ExtendedConfig {

    private static final Logger LOGGER = Logger.getLogger(CommonConfig.class.getName());
    private static final Function<Object, Binder> CAST_TO_BINDER = Binder.class::cast;

    
Configuration runtime type.
/**
     * Configuration runtime type.
     */
    private final RuntimeType type;
    
Configuration properties collection and it's immutable views.
/**
     * Configuration properties collection and it's immutable views.
     */
    private final Map<String, Object> properties;
    private final Map<String, Object> immutablePropertiesView;
    private final Collection<String> immutablePropertyNames;
    
Configured providers, does not include features and binders.
/**
     * Configured providers, does not include features and binders.
     */
    private final ComponentBag componentBag;
    
Collection of unprocessed feature registrations.
/**
     * Collection of unprocessed feature registrations.
     */
    private final List<FeatureRegistration> newFeatureRegistrations;
    
Collection of enabled feature classes.
/**
     * Collection of enabled feature classes.
     */
    private final Set<Class<? extends Feature>> enabledFeatureClasses;
    
Collection of enabled feature instances.
/**
     * Collection of enabled feature instances.
     */
    private final Set<Feature> enabledFeatures;

    
Flag determining whether the configuration of meta-providers (excl. binders) should be disabled.
/**
     * Flag determining whether the configuration of meta-providers (excl. binders) should be disabled.
     */
    private boolean disableMetaProviderConfiguration;

    
A single feature registration record.
/**
     * A single feature registration record.
     */
    private static final class FeatureRegistration {

        private final Class<? extends Feature> featureClass;
        private final Feature feature;
        private final RuntimeType runtimeType;

        private FeatureRegistration(final Class<? extends Feature> featureClass) {
            this.featureClass = featureClass;
            this.feature = null;
            final ConstrainedTo runtimeTypeConstraint = featureClass.getAnnotation(ConstrainedTo.class);
            this.runtimeType = runtimeTypeConstraint == null ? null : runtimeTypeConstraint.value();
        }

        private FeatureRegistration(final Feature feature) {
            this.featureClass = feature.getClass();
            this.feature = feature;
            final ConstrainedTo runtimeTypeConstraint = featureClass.getAnnotation(ConstrainedTo.class);
            this.runtimeType = runtimeTypeConstraint == null ? null : runtimeTypeConstraint.value();
        }

        
Get the registered feature class.
Returns:
registered feature class./**
         * Get the registered feature class.
         *
         * @return registered feature class.
         */
        private Class<? extends Feature> getFeatureClass() {
            return featureClass;
        }

        
Get the registered feature instance or null if this is a class based feature registration. 
Returns:
the registered feature instance or null if this is a class based feature registration./**
         * Get the registered feature instance or {@code null} if this is a
         * class based feature registration.
         *
         * @return the registered feature instance or {@code null} if this is a
         *         class based feature registration.
         */
        private Feature getFeature() {
            return feature;
        }

        
Get the RuntimeType constraint given by ConstrainedTo annotated the Feature or null if not annotated. 
Returns:
the RuntimeType constraint given by ConstrainedTo annotated the Feature or null if not annotated./**
         * Get the {@code RuntimeType} constraint given by {@code ConstrainedTo} annotated
         * the Feature or {@code null} if not annotated.
         *
         * @return the {@code RuntimeType} constraint given by {@code ConstrainedTo} annotated
         *         the Feature or {@code null} if not annotated.
         */
        private RuntimeType getFeatureRuntimeType() {
            return runtimeType;
        }

        @Override
        public boolean equals(final Object obj) {
            if (this == obj) {
                return true;
            }
            if (!(obj instanceof FeatureRegistration)) {
                return false;
            }
            final FeatureRegistration other = (FeatureRegistration) obj;

            return (featureClass == other.featureClass)
                    || (feature != null && (feature == other.feature || feature.equals(other.feature)));
        }

        @Override
        public int hashCode() {
            int hash = 47;
            hash = 13 * hash + (feature != null ? feature.hashCode() : 0);
            hash = 13 * hash + (featureClass != null ? featureClass.hashCode() : 0);
            return hash;
        }
    }

    
Create a new RuntimeConfig instance. 
 The constructor provides a way for defining a contract
provider model registration strategy. Once a registration model is built for a newly registered contract, the provided registration strategy filter is consulted whether the model should be registered or not. 

Clients can use the method to cancel any contract provider model registration
that does not meet the criteria of a given configuration context, such as a model
that does not have any recognized contracts associated with it.

Params:
type –                 configuration runtime type.
registrationStrategy – function driving the decision (based on the introspected contract provider model) whether or not should the component class registration continue towards a successful completion./**
     * Create a new {@code RuntimeConfig} instance.
     * <p>
     * The constructor provides a way for defining a {@link ContractProvider contract
     * provider model} registration strategy. Once a registration model is built
     * for a newly registered contract, the provided registration strategy filter is
     * consulted whether the model should be registered or not.
     * </p>
     * <p>
     * Clients can use the method to cancel any contract provider model registration
     * that does not meet the criteria of a given configuration context, such as a model
     * that does not have any recognized contracts associated with it.
     * </p>
     *
     * @param type                 configuration runtime type.
     * @param registrationStrategy function driving the decision (based on the introspected
     *                             {@link ContractProvider contract provider model}) whether
     *                             or not should the component class registration continue
     *                             towards a successful completion.
     */
    public CommonConfig(final RuntimeType type, final Predicate<ContractProvider> registrationStrategy) {
        this.type = type;

        this.properties = new HashMap<>();
        this.immutablePropertiesView = Collections.unmodifiableMap(properties);
        this.immutablePropertyNames = Collections.unmodifiableCollection(properties.keySet());

        this.componentBag = ComponentBag.newInstance(registrationStrategy);

        this.newFeatureRegistrations = new LinkedList<>();

        this.enabledFeatureClasses = Collections.newSetFromMap(new IdentityHashMap<>());
        this.enabledFeatures = new HashSet<>();

        this.disableMetaProviderConfiguration = false;
    }

    
Copy constructor.
Params:
config – configurable to copy class properties from./**
     * Copy constructor.
     *
     * @param config configurable to copy class properties from.
     */
    public CommonConfig(final CommonConfig config) {
        this.type = config.type;

        this.properties = new HashMap<>(config.properties.size());
        this.immutablePropertiesView = Collections.unmodifiableMap(this.properties);
        this.immutablePropertyNames = Collections.unmodifiableCollection(this.properties.keySet());

        this.componentBag = config.componentBag.copy();

        this.newFeatureRegistrations = new LinkedList<>();
        this.enabledFeatureClasses = Collections.newSetFromMap(new IdentityHashMap<>());
        this.enabledFeatures = new HashSet<>();

        copy(config, false);
    }

    
Copy config properties, providers from given config to this instance. 
Params:
config – configurable to copy class properties from.
loadComponentBag – true if the component bag from config should be copied as well, false otherwise./**
     * Copy config properties, providers from given {@code config} to this instance.
     *
     * @param config configurable to copy class properties from.
     * @param loadComponentBag {@code true} if the component bag from config should be copied as well, {@code false} otherwise.
     */
    private void copy(final CommonConfig config, final boolean loadComponentBag) {
        this.properties.clear();
        this.properties.putAll(config.properties);

        this.newFeatureRegistrations.clear();
        this.newFeatureRegistrations.addAll(config.newFeatureRegistrations);

        this.enabledFeatureClasses.clear();
        this.enabledFeatureClasses.addAll(config.enabledFeatureClasses);

        this.enabledFeatures.clear();
        this.enabledFeatures.addAll(config.enabledFeatures);

        this.disableMetaProviderConfiguration = config.disableMetaProviderConfiguration;

        if (loadComponentBag) {
            this.componentBag.loadFrom(config.componentBag);
        }
    }

    @Override
    public ExtendedConfig getConfiguration() {
        return this;
    }

    @Override
    public RuntimeType getRuntimeType() {
        return type;
    }

    @Override
    public Map<String, Object> getProperties() {
        return immutablePropertiesView;
    }

    @Override
    public Object getProperty(final String name) {
        return properties.get(name);
    }

    @Override
    public boolean isProperty(final String name) {
        return PropertiesHelper.isProperty(getProperty(name));
    }

    @Override
    public Collection<String> getPropertyNames() {
        return immutablePropertyNames;
    }

    @Override
    public boolean isEnabled(final Class<? extends Feature> featureClass) {
        return enabledFeatureClasses.contains(featureClass);
    }

    @Override
    public boolean isEnabled(final Feature feature) {
        return enabledFeatures.contains(feature);
    }

    @Override
    public boolean isRegistered(final Object component) {
        return componentBag.getInstances().contains(component);
    }

    @Override
    public boolean isRegistered(final Class<?> componentClass) {
        return componentBag.getRegistrations().contains(componentClass);
    }

    @Override
    public Map<Class<?>, Integer> getContracts(final Class<?> componentClass) {
        final ContractProvider model = componentBag.getModel(componentClass);
        return (model == null) ? Collections.emptyMap() : model.getContractMap();
    }

    @Override
    public Set<Class<?>> getClasses() {
        return componentBag.getClasses();
    }

    @Override
    public Set<Object> getInstances() {
        return componentBag.getInstances();
    }

    
Returns a ComponentBag instance associated with the configuration. 
Returns:
a non-null component bag instance./**
     * Returns a {@link ComponentBag} instance associated with the configuration.
     *
     * @return a non-null component bag instance.
     */
    public final ComponentBag getComponentBag() {
        return componentBag;
    }

    
An extension point that provides a way how to define a custom enhancement/update
operation of a contract provider model registration being produced for a given
component class.
Default implementation return an enhancer just builds the model.

Derived implementations may use this method to e.g. filter out all contracts not
applicable in the given configuration context or change the model scope. The returned
set of filtered contracts is then used for the actual provider registration.

Params:
componentClass – class of the component being registered.
Returns:
filter for the contracts that being registered for a given component class./**
     * An extension point that provides a way how to define a custom enhancement/update
     * operation of a contract provider model registration being produced for a given
     * component class.
     * Default implementation return an enhancer just builds the model.
     * <p>
     * Derived implementations may use this method to e.g. filter out all contracts not
     * applicable in the given configuration context or change the model scope. The returned
     * set of filtered contracts is then used for the actual provider registration.
     * </p>
     *
     * @param componentClass class of the component being registered.
     * @return filter for the contracts that being registered for a given component class.
     */
    protected Inflector<ContractProvider.Builder, ContractProvider> getModelEnhancer(final Class<?> componentClass) {
        return ComponentBag.AS_IS;
    }

    
Set the configured properties to the provided map of properties.
Params:
properties – new map of properties to be set.
Returns:
updated configuration instance./**
     * Set the configured properties to the provided map of properties.
     *
     * @param properties new map of properties to be set.
     * @return updated configuration instance.
     */
    public CommonConfig setProperties(final Map<String, ?> properties) {
        this.properties.clear();

        if (properties != null) {
            this.properties.putAll(properties);
        }
        return this;
    }

    
Add properties to ResourceConfig. If any of the added properties exists already, he values of the existing properties will be replaced with new values. 
Params:
properties – properties to add.
Returns:
updated configuration instance./**
     * Add properties to {@code ResourceConfig}.
     *
     * If any of the added properties exists already, he values of the existing
     * properties will be replaced with new values.
     *
     * @param properties properties to add.
     * @return updated configuration instance.
     */
    public CommonConfig addProperties(final Map<String, ?> properties) {
        if (properties != null) {
            this.properties.putAll(properties);
        }
        return this;
    }

    @Override
    public CommonConfig property(final String name, final Object value) {
        if (value == null) {
            properties.remove(name);
        } else {
            properties.put(name, value);
        }
        return this;
    }

    @Override
    public CommonConfig register(final Class<?> componentClass) {
        checkComponentClassNotNull(componentClass);
        if (componentBag.register(componentClass, getModelEnhancer(componentClass))) {
            processFeatureRegistration(null, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Class<?> componentClass, final int bindingPriority) {
        checkComponentClassNotNull(componentClass);
        if (componentBag.register(componentClass, bindingPriority, getModelEnhancer(componentClass))) {
            processFeatureRegistration(null, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Class<?> componentClass, final Class<?>... contracts) {
        checkComponentClassNotNull(componentClass);
        if (contracts == null || contracts.length == 0) {
            LOGGER.warning(LocalizationMessages.COMPONENT_CONTRACTS_EMPTY_OR_NULL(componentClass));
            return this;
        }
        if (componentBag.register(componentClass, asNewIdentitySet(contracts), getModelEnhancer(componentClass))) {
            processFeatureRegistration(null, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Class<?> componentClass, final Map<Class<?>, Integer> contracts) {
        checkComponentClassNotNull(componentClass);
        if (componentBag.register(componentClass, contracts, getModelEnhancer(componentClass))) {
            processFeatureRegistration(null, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Object component) {
        checkProviderNotNull(component);

        final Class<?> componentClass = component.getClass();
        if (componentBag.register(component, getModelEnhancer(componentClass))) {
            processFeatureRegistration(component, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Object component, final int bindingPriority) {
        checkProviderNotNull(component);
        final Class<?> componentClass = component.getClass();
        if (componentBag.register(component, bindingPriority, getModelEnhancer(componentClass))) {
            processFeatureRegistration(component, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Object component, final Class<?>... contracts) {
        checkProviderNotNull(component);
        final Class<?> componentClass = component.getClass();
        if (contracts == null || contracts.length == 0) {
            LOGGER.warning(LocalizationMessages.COMPONENT_CONTRACTS_EMPTY_OR_NULL(componentClass));
            return this;
        }
        if (componentBag.register(component, asNewIdentitySet(contracts), getModelEnhancer(componentClass))) {
            processFeatureRegistration(component, componentClass);
        }

        return this;
    }

    @Override
    public CommonConfig register(final Object component, final Map<Class<?>, Integer> contracts) {
        checkProviderNotNull(component);
        final Class<?> componentClass = component.getClass();
        if (componentBag.register(component, contracts, getModelEnhancer(componentClass))) {
            processFeatureRegistration(component, componentClass);
        }

        return this;
    }

    private void processFeatureRegistration(final Object component, final Class<?> componentClass) {
        final ContractProvider model = componentBag.getModel(componentClass);
        if (model.getContracts().contains(Feature.class)) {
            @SuppressWarnings("unchecked")
            final FeatureRegistration registration = (component != null)
                    ? new FeatureRegistration((Feature) component)
                    : new FeatureRegistration((Class<? extends Feature>) componentClass);
            newFeatureRegistrations.add(registration);
        }
    }

    
Load the internal configuration state from an externally provided configuration state.

Calling this method effectively replaces existing configuration state of the instance with the state represented by the
externally provided configuration. If the features, auto-discoverables of given config has been already configured then
this method will make sure to not configure them for the second time.
Params:
config – external configuration state to replace the configuration of this configurable instance.
Returns:
the updated common configuration instance./**
     * Load the internal configuration state from an externally provided configuration state.
     * <p/>
     * Calling this method effectively replaces existing configuration state of the instance with the state represented by the
     * externally provided configuration. If the features, auto-discoverables of given config has been already configured then
     * this method will make sure to not configure them for the second time.
     *
     * @param config external configuration state to replace the configuration of this configurable instance.
     * @return the updated common configuration instance.
     */
    public CommonConfig loadFrom(final Configuration config) {
        if (config instanceof CommonConfig) {
            // If loading from CommonConfig then simply copy properties and check whether given config has been initialized.
            final CommonConfig commonConfig = (CommonConfig) config;

            copy(commonConfig, true);
            this.disableMetaProviderConfiguration = !commonConfig.enabledFeatureClasses.isEmpty();
        } else {
            setProperties(config.getProperties());

            this.enabledFeatures.clear();
            this.enabledFeatureClasses.clear();

            componentBag.clear();
            resetRegistrations();

            for (final Class<?> clazz : config.getClasses()) {
                if (Feature.class.isAssignableFrom(clazz) && config.isEnabled((Class<? extends Feature>) clazz)) {
                    this.disableMetaProviderConfiguration = true;
                }

                register(clazz, config.getContracts(clazz));
            }

            for (final Object instance : config.getInstances()) {
                if (instance instanceof Feature && config.isEnabled((Feature) instance)) {
                    this.disableMetaProviderConfiguration = true;
                }

                register(instance, config.getContracts(instance.getClass()));
            }
        }

        return this;
    }

    private Set<Class<?>> asNewIdentitySet(final Class<?>... contracts) {
        final Set<Class<?>> result = Collections.newSetFromMap(new IdentityHashMap<>());
        result.addAll(Arrays.asList(contracts));
        return result;
    }

    private void checkProviderNotNull(final Object provider) {
        if (provider == null) {
            throw new IllegalArgumentException(LocalizationMessages.COMPONENT_CANNOT_BE_NULL());
        }
    }

    private void checkComponentClassNotNull(final Class<?> componentClass) {
        if (componentClass == null) {
            throw new IllegalArgumentException(LocalizationMessages.COMPONENT_CLASS_CANNOT_BE_NULL());
        }
    }

    
Configure auto-discoverables in the injection manager. 
Params:
injectionManager –  injection manager in which the auto-discoverables should be configured.
autoDiscoverables – list of registered auto discoverable components.
forcedOnly –        defines whether all or only forced auto-discoverables should be configured./**
     * Configure {@link AutoDiscoverable auto-discoverables} in the injection manager.
     *
     * @param injectionManager  injection manager in which the auto-discoverables should be configured.
     * @param autoDiscoverables list of registered auto discoverable components.
     * @param forcedOnly        defines whether all or only forced auto-discoverables should be configured.
     */
    public void configureAutoDiscoverableProviders(final InjectionManager injectionManager,
                                                   final Collection<AutoDiscoverable> autoDiscoverables,
                                                   final boolean forcedOnly) {
        // Check whether meta providers have been initialized for a config this config has been loaded from.
        if (!disableMetaProviderConfiguration) {
            final Set<AutoDiscoverable> providers = new TreeSet<>((o1, o2) -> {
                final int p1 = o1.getClass().isAnnotationPresent(Priority.class)
                        ? o1.getClass().getAnnotation(Priority.class).value() : Priorities.USER;
                final int p2 = o2.getClass().isAnnotationPresent(Priority.class)
                        ? o2.getClass().getAnnotation(Priority.class).value() : Priorities.USER;

                return (p1 < p2 || p1 == p2) ? -1 : 1;
            });

            // Forced (always invoked).
            final List<ForcedAutoDiscoverable> forcedAutoDiscroverables = new LinkedList<>();
            for (Class<ForcedAutoDiscoverable> forcedADType : ServiceFinder.find(ForcedAutoDiscoverable.class, true)
                    .toClassArray()) {
                forcedAutoDiscroverables.add(injectionManager.createAndInitialize(forcedADType));
            }
            providers.addAll(forcedAutoDiscroverables);

            // Regular.
            if (!forcedOnly) {
                providers.addAll(autoDiscoverables);
            }

            for (final AutoDiscoverable autoDiscoverable : providers) {
                final ConstrainedTo constrainedTo = autoDiscoverable.getClass().getAnnotation(ConstrainedTo.class);

                if (constrainedTo == null || type.equals(constrainedTo.value())) {
                    try {
                        autoDiscoverable.configure(this);
                    } catch (final Exception e) {
                        LOGGER.log(Level.FINE,
                                LocalizationMessages.AUTODISCOVERABLE_CONFIGURATION_FAILED(autoDiscoverable.getClass()), e);
                    }
                }
            }
        }
    }

    
Configure binders in the injection manager and enable JAX-RS features.
Params:
injectionManager – injection manager in which the binders and features should be configured./**
     * Configure binders in the injection manager and enable JAX-RS features.
     *
     * @param injectionManager injection manager in which the binders and features should be configured.
     */
    public void configureMetaProviders(InjectionManager injectionManager, ManagedObjectsFinalizer finalizer) {
        final Set<Object> configuredExternals = Collections.newSetFromMap(new IdentityHashMap<>());

        // First, configure existing binders
        final Set<Binder> configuredBinders = configureBinders(injectionManager, Collections.emptySet());

        // Check whether meta providers have been initialized for a config this config has been loaded from.
        if (!disableMetaProviderConfiguration) {
            // Next, register external meta objects
            configureExternalObjects(injectionManager, configuredExternals);
            // Configure all features
            configureFeatures(injectionManager, new HashSet<>(), resetRegistrations(), finalizer);
            // Next, register external meta objects registered by features
            configureExternalObjects(injectionManager, configuredExternals);
            // At last, configure any new binders added by features
            configureBinders(injectionManager, configuredBinders);
        }
    }

    private Set<Binder> configureBinders(InjectionManager injectionManager, Set<Binder> configured) {
        Set<Binder> allConfigured = Collections.newSetFromMap(new IdentityHashMap<>());
        allConfigured.addAll(configured);

        Collection<Binder> binders = getBinder(configured);
        if (!binders.isEmpty()) {
            injectionManager.register(CompositeBinder.wrap(binders));
            allConfigured.addAll(binders);
        }

        return allConfigured;
    }

    private Collection<Binder> getBinder(Set<Binder> configured) {
        return componentBag.getInstances(ComponentBag.BINDERS_ONLY)
                .stream()
                .map(CAST_TO_BINDER)
                .filter(binder -> !configured.contains(binder))
                .collect(Collectors.toList());
    }

    private void configureExternalObjects(InjectionManager injectionManager, Set<Object> externalObjects) {
        Consumer<Object> registerOnce = o -> {
            if (!externalObjects.contains(o)) {
                injectionManager.register(o);
                externalObjects.add(o);
            }
        };
        componentBag.getInstances(model -> ComponentBag.EXTERNAL_ONLY.test(model, injectionManager))
                .forEach(registerOnce);
        componentBag.getClasses(model -> ComponentBag.EXTERNAL_ONLY.test(model, injectionManager))
                .forEach(registerOnce);
    }

    private void configureFeatures(InjectionManager injectionManager,
                                   Set<FeatureRegistration> processed,
                                   List<FeatureRegistration> unprocessed,
                                   ManagedObjectsFinalizer managedObjectsFinalizer) {
        FeatureContextWrapper featureContextWrapper = null;
        for (final FeatureRegistration registration : unprocessed) {
            if (processed.contains(registration)) {
                LOGGER.config(LocalizationMessages.FEATURE_HAS_ALREADY_BEEN_PROCESSED(registration.getFeatureClass()));
                continue;
            }

            final RuntimeType runtimeTypeConstraint = registration.getFeatureRuntimeType();
            if (runtimeTypeConstraint != null && !type.equals(runtimeTypeConstraint)) {
                LOGGER.config(LocalizationMessages.FEATURE_CONSTRAINED_TO_IGNORED(
                        registration.getFeatureClass(), registration.runtimeType, type));
                continue;
            }

            Feature feature = registration.getFeature();
            if (feature == null) {
                feature = injectionManager.createAndInitialize(registration.getFeatureClass());
                managedObjectsFinalizer.registerForPreDestroyCall(feature);
            } else {
                // Disable injection of Feature instances on the client-side. Instances may be registered into multiple
                // web-targets which means that injecting anything into these instances is not safe.
                if (!RuntimeType.CLIENT.equals(type)) {
                    injectionManager.inject(feature);
                }
            }

            if (enabledFeatures.contains(feature)) {
                LOGGER.config(LocalizationMessages.FEATURE_HAS_ALREADY_BEEN_PROCESSED(feature));
                continue;
            }

            if (featureContextWrapper == null) {
                // init lazily
                featureContextWrapper = new FeatureContextWrapper(this, injectionManager);
            }
            final boolean success = feature.configure(featureContextWrapper);

            if (success) {
                processed.add(registration);
                final ContractProvider providerModel = componentBag.getModel(feature.getClass());
                if (providerModel != null) {
                    ProviderBinder.bindProvider(feature, providerModel, injectionManager);
                }
                configureFeatures(injectionManager, processed, resetRegistrations(), managedObjectsFinalizer);
                enabledFeatureClasses.add(registration.getFeatureClass());
                enabledFeatures.add(feature);
            }
        }
    }

    private List<FeatureRegistration> resetRegistrations() {
        final List<FeatureRegistration> result = new ArrayList<>(newFeatureRegistrations);
        newFeatureRegistrations.clear();
        return result;
    }

    @Override
    public boolean equals(final Object o) {
        if (this == o) {
            return true;
        }
        if (!(o instanceof CommonConfig)) {
            return false;
        }

        final CommonConfig that = (CommonConfig) o;

        if (type != that.type) {
            return false;
        }
        if (!properties.equals(that.properties)) {
            return false;
        }
        if (!componentBag.equals(that.componentBag)) {
            return false;
        }
        if (!enabledFeatureClasses.equals(that.enabledFeatureClasses)) {
            return false;
        }
        if (!enabledFeatures.equals(that.enabledFeatures)) {
            return false;
        }
        if (!newFeatureRegistrations.equals(that.newFeatureRegistrations)) {
            return false;
        }

        return true;
    }

    @Override
    public int hashCode() {
        int result = type.hashCode();
        result = 31 * result + properties.hashCode();
        result = 31 * result + componentBag.hashCode();
        result = 31 * result + newFeatureRegistrations.hashCode();
        result = 31 * result + enabledFeatures.hashCode();
        result = 31 * result + enabledFeatureClasses.hashCode();
        return result;
    }
}