package com.fasterxml.jackson.datatype.hibernate4;

import com.fasterxml.jackson.core.Version;
import com.fasterxml.jackson.databind.AnnotationIntrospector;
import com.fasterxml.jackson.databind.Module;
import org.hibernate.SessionFactory;
import org.hibernate.engine.spi.Mapping;

public class Hibernate4Module extends com.fasterxml.jackson.databind.Module
{
    
Enumeration that defines all toggleable features this module
/**
     * Enumeration that defines all toggleable features this module
     */
    public enum Feature {
        
Whether lazy-loaded object should be forced to be loaded and then serialized
(true); or serialized as nulls (false).

Default value is false.
/**
         * Whether lazy-loaded object should be forced to be loaded and then serialized
         * (true); or serialized as nulls (false).
         *<p>
         * Default value is false.
         */
        FORCE_LAZY_LOADING(false),

        
Whether Transient annotation should be checked or not; if true, will consider @Transient to mean that property is to be ignored; if false annotation will have no effect. 

Default value is true.
/**
         * Whether {@link javax.persistence.Transient} annotation should be checked or not;
         * if true, will consider {@code @Transient} to mean that property is to be ignored;
         * if false annotation will have no effect.
         *<p>
         * Default value is true.
         */
        USE_TRANSIENT_ANNOTATION(true),
        
	    
If FORCE_LAZY_LOADING is false, this feature serializes uninitialized lazy loading proxies as
{"identifierName":"identifierValue"} rather than null. 

Default value is false.

Note that the name of the identifier property can only be determined if 

the Mapping is provided to the Hibernate4Module, or 
the persistence context that loaded the proxy has not yet been closed, or
 
the id property is mapped with property access (for instance because the @Id annotation is applied to a method rather than a field)

Otherwise, the entity name will be used instead. 
/**
	     * If FORCE_LAZY_LOADING is false, this feature serializes uninitialized lazy loading proxies as
	     * <code>{"identifierName":"identifierValue"}</code> rather than <code>null</code>. 
	     * <p>
         * Default value is false.
	     * <p>
	     * Note that the name of the identifier property can only be determined if 
	     * <ul>
	     * <li>the {@link Mapping} is provided to the Hibernate4Module, or </li>
	     * <li>the persistence context that loaded the proxy has not yet been closed, or</li> 
	     * <li>the id property is mapped with property access (for instance because the {@code @Id}
	     * annotation is applied to a method rather than a field)</li>
	     * </ul>
	     * Otherwise, the entity name will be used instead. 
	     */
        SERIALIZE_IDENTIFIER_FOR_LAZY_NOT_LOADED_OBJECTS(false),

        
This feature determines how PersistentCollections properties for which no annotation is found are handled with respect to lazy-loading: if true, lazy-loading is only assumed if annotation is used to indicate that; if false, lazy-loading is assumed to be the default. Note that FORCE_LAZY_LOADING has priority over this Feature; meaning that if it is defined as true, setting of this Feature has no effect. 

Default value is false, meaning that laziness is considered to be the
default value.
Since:
2.4/**
         * This feature determines how {@link org.hibernate.collection.spi.PersistentCollection}s properties
         * for which no annotation is found are handled with respect to
         * lazy-loading: if true, lazy-loading is only assumed if annotation
         * is used to indicate that; if false, lazy-loading is assumed to be
         * the default.
         * Note that {@link #FORCE_LAZY_LOADING} has priority over this Feature;
         * meaning that if it is defined as true, setting of this Feature has no
         * effect.
          * <p>
          * Default value is false, meaning that laziness is considered to be the
          * default value.
         * 
         * @since 2.4
         */
        REQUIRE_EXPLICIT_LAZY_LOADING_MARKER(false),

        
Feature that may be enabled to force
replacement org.hibernate.collection.spi.PersistentCollection,
List, Set, Map subclasses during serialization as standard JDK List, Set and Map. This is usually done to prevent issues with polymorphic handling, so that type id is generated for standard containers and NOT for Hibernate variants. 

Default setting is false, so that no replacement occurs.
Since:
2.8.2/**
         * Feature that may be enabled to force
         * replacement <code>org.hibernate.collection.spi.PersistentCollection</code>,
         * <code>List</code>, <code>Set</code>, <code>Map</code> subclasses
         * during serialization as standard JDK {@link java.util.List},
         * {@link java.util.Set} and {@link java.util.Map}.
         * This is usually done to prevent issues with polymorphic handling, so
         * that type id is generated for standard containers and NOT for Hibernate
         * variants.
         * <p>
         * Default setting is false, so that no replacement occurs.
         *
         * @since 2.8.2
         */
        REPLACE_PERSISTENT_COLLECTIONS(false),
        
        
Using FORCE_LAZY_LOADING may result in `javax.persistence.EntityNotFoundException`. This flag configures Jackson to ignore the error and serialize a `null`. 
Since:
2.10/**
         * Using {@link #FORCE_LAZY_LOADING} may result in
         * `javax.persistence.EntityNotFoundException`. This flag configures Jackson to
         * ignore the error and serialize a `null`.
         *
         * @since 2.10
         */
        WRITE_MISSING_ENTITIES_AS_NULL(false)
        ;

        final boolean _defaultState;
        final int _mask;

        
Method that calculates bit set (flags) of all features that
are enabled by default.
/**
         * Method that calculates bit set (flags) of all features that
         * are enabled by default.
         */
        public static int collectDefaults()
        {
            int flags = 0;
            for (Feature f : values()) {
                if (f.enabledByDefault()) {
                    flags |= f.getMask();
                }
            }
            return flags;
        }
        
        private Feature(boolean defaultState) {
            _defaultState = defaultState;
            _mask = (1 << ordinal());
        }

        public boolean enabledIn(int flags) { return (flags & _mask) != 0; }
        public boolean enabledByDefault() { return _defaultState; }
        public int getMask() { return _mask; }
    }

    protected final static int DEFAULT_FEATURES = Feature.collectDefaults();
    
    
Bit flag composed of bits that indicate which Features are enabled. /**
     * Bit flag composed of bits that indicate which
     * {@link Feature}s
     * are enabled.
     */
    protected int _moduleFeatures = DEFAULT_FEATURES;

    
Hibernate mapping.
/**
     * Hibernate mapping.
     */
    protected final Mapping _mapping;

    protected final SessionFactory _sessionFactory;

    /*
    /**********************************************************************
    /* Life-cycle
    /**********************************************************************
     */

    public Hibernate4Module() {
        this(null, null);
    }

    public Hibernate4Module(Mapping mapping) {
        this(mapping, null);
    }

    public Hibernate4Module(SessionFactory sessionFactory) {
        this(null, sessionFactory);
    }

    public Hibernate4Module(Mapping mapping, SessionFactory sessionFactory) {
        _sessionFactory = sessionFactory;
        _mapping = mapping;
    }

    @Override public String getModuleName() { return "jackson-datatype-hibernate"; }
    @Override public Version version() { return PackageVersion.VERSION; }

    @Override
    public void setupModule(SetupContext context)
    {
        /* First, append annotation introspector (no need to override, esp.
         * as we just implement couple of methods)
         */
        // Then add serializers we need
        AnnotationIntrospector ai = annotationIntrospector();
        if (ai != null) {
            context.appendAnnotationIntrospector(ai);
        }
        context.addSerializers(new HibernateSerializers(_mapping, _moduleFeatures));
        context.addBeanSerializerModifier(new HibernateSerializerModifier(_moduleFeatures, _sessionFactory));
    }

    
Method called during setupModule, to create AnnotationIntrospector to register along with module. If null is returned, no introspector is added. /**
     * Method called during {@link #setupModule}, to create {@link com.fasterxml.jackson.databind.AnnotationIntrospector}
     * to register along with module. If null is returned, no introspector is added.
     */
    protected AnnotationIntrospector annotationIntrospector() {
        HibernateAnnotationIntrospector ai = new HibernateAnnotationIntrospector();
        ai.setUseTransient(isEnabled(Feature.USE_TRANSIENT_ANNOTATION));
        return ai;
    }
    
    /*
    /**********************************************************************
    /* Extended API, configuration
    /**********************************************************************
     */

    public Hibernate4Module enable(Feature f) {
        _moduleFeatures |= f.getMask();
        return this;
    }

    public Hibernate4Module disable(Feature f) {
        _moduleFeatures &= ~f.getMask();
        return this;
    }

    public final boolean isEnabled(Feature f) {
        return (_moduleFeatures & f.getMask()) != 0;
    }

    public Hibernate4Module configure(Feature f, boolean state) {
        if (state) {
            enable(f);
        } else {
            disable(f);
        }
        return this;
    }

}