EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.model.term;

import java.rmi.UnexpectedException;

import java.util.ArrayList;

import java.util.HashSet;

import java.util.List;

import java.util.Set;

import java.util.UUID;

import javax.persistence.Column;

import javax.persistence.Entity;

import javax.persistence.FetchType;

import javax.persistence.OneToMany;

import javax.persistence.OneToOne;

import javax.persistence.Transient;

import javax.validation.constraints.NotNull;

import javax.xml.bind.annotation.XmlAccessType;

import javax.xml.bind.annotation.XmlAccessorType;

import javax.xml.bind.annotation.XmlAttribute;

import javax.xml.bind.annotation.XmlElement;

import javax.xml.bind.annotation.XmlElementWrapper;

import javax.xml.bind.annotation.XmlRootElement;

import javax.xml.bind.annotation.XmlType;

import org.apache.log4j.Logger;

import org.hibernate.annotations.Cascade;

import org.hibernate.annotations.CascadeType;

import org.hibernate.annotations.Type;

import org.hibernate.envers.Audited;

import eu.etaxonomy.cdm.model.common.IdentifiableEntity;

import eu.etaxonomy.cdm.model.description.DescriptionElementBase;

import eu.etaxonomy.cdm.model.description.Feature;

import eu.etaxonomy.cdm.model.description.MediaKey;

import eu.etaxonomy.cdm.strategy.cache.common.IIdentifiableEntityCacheStrategy;

/**

 * The class to arrange {@link Feature features} (characters) in a tree structure.

 * Feature trees are essential as interactive multiple-access keys for

 * determination process and for systematical output arrangement of

 * {@link DescriptionElementBase description elements} according to different goals

 * but may also be used to define flat feature subsets for filtering purposes.<BR>

 * A feature tree is build on {@link FeatureNode feature nodes}.

 * <P>

 * This class corresponds partially to ConceptTreeDefType according to the SDD

 * schema.

 * <P>

 * Note: The tree structure of features used for purposes described above has

 * nothing in common with the possible hierarchical structure of features

 * depending on their grade of precision.

 *

 * @see		MediaKey

 *

 * @author  m.doering

 * @since 08-Nov-2007 13:06:16

 */

@XmlAccessorType(XmlAccessType.FIELD)

@XmlType(name = "FeatureTree", propOrder = {

    "root",

    "termType",

    "allowDuplicates",

    "representations"

})

@XmlRootElement(name = "FeatureTree")

@Entity

//@Indexed disabled to reduce clutter in indexes, since this type is not used by any search

//@Indexed(index = "eu.etaxonomy.cdm.model.term.FeatureTree")

@Audited

public class FeatureTree <T extends DefinedTermBase>

            extends IdentifiableEntity<IIdentifiableEntityCacheStrategy>

            implements IHasTermType, Cloneable{

	private static final long serialVersionUID = -6713834139003172735L;

	private static final Logger logger = Logger.getLogger(FeatureTree.class);

	@XmlElement(name = "Root")

	@OneToOne(fetch = FetchType.LAZY, targetEntity=FeatureNode.class)

	@Cascade({CascadeType.SAVE_UPDATE, CascadeType.MERGE})

	private FeatureNode<T> root;

    /**

     * The {@link TermType type} of this term collection. All nodes in the graph must refer to a term of the same type.

     */

    @XmlAttribute(name ="TermType")

    @Column(name="termType")

    @NotNull

    @Type(type = "eu.etaxonomy.cdm.hibernate.EnumUserType",

        parameters = {@org.hibernate.annotations.Parameter(name  = "enumClass", value = "eu.etaxonomy.cdm.model.term.TermType")}

    )

    @Audited

    private TermType termType;

    // TODO needed? FeatureTree was a TermBase until v3.3 but was removed from

	//it as TermBase got the termType which does not apply to FeatureTree.

	//We need to check how far representations and uri is still required

	//or can be deleted. Current implementations seem all to use the title cache

	//instead of representation. This may not be correct.

	@XmlElementWrapper(name = "Representations")

    @XmlElement(name = "Representation")

    @OneToMany(fetch=FetchType.EAGER, orphanRemoval=true)

    @Cascade( { CascadeType.SAVE_UPDATE, CascadeType.MERGE, CascadeType.DELETE})

    // @IndexedEmbedded no need for embedding since we are using the DefinedTermBaseClassBridge

    private Set<Representation> representations = new HashSet<>();

    //make them private for now as we may delete representations in future

	//otherwise if we decide to use representations we can make the getters public

	private Set<Representation> getRepresentations() {return representations;}

    private void setRepresentations(Set<Representation> representations) {this.representations = representations;}

    //#7372 indicates if this tree/graph allows duplicated terms/features

    private boolean allowDuplicates = false;

//******************** FACTORY METHODS ******************************************/

    /**

     * Creates a new term collection instance for the given term type

     * with an empty {@link #getRoot() root node}.

     * @param termType the {@link TermType term type}, must not be null

     */

    public static <T extends DefinedTermBase<T>> FeatureTree<T> NewInstance(@NotNull TermType termType){

        return new FeatureTree<>(termType);

    }

    /**

	 * Creates a new feature tree instance with an empty {@link #getRoot() root node}.

	 *

	 * @see #NewInstance(UUID)

	 * @see #NewInstance(List)

	 */

	public static FeatureTree<Feature> NewInstance(){

		return new FeatureTree<>(TermType.Feature);

	}

	/**

	 * Creates a new feature tree instance with an empty {@link #getRoot() root node}

	 * and assigns to the new feature tree the given

	 * UUID (universally unique identifier).

	 *

	 * @param	uuid	the universally unique identifier

	 * @see 			#NewInstance()

	 * @see 			#NewInstance(List)

	 */

	public static <T extends DefinedTermBase<T>> FeatureTree<T> NewInstance(UUID uuid){

		FeatureTree<T> result =  new FeatureTree<>(TermType.Feature);

		result.setUuid(uuid);

		return result;

	}

	/**

	 * Creates a new feature tree instance with a {@link #getRoot() root node}

	 * the children of which are the feature nodes build on the base of the

	 * given list of {@link Feature features}. This corresponds to a flat feature tree.

	 * For each feature within the list a new {@link FeatureNode feature node} without

	 * children nodes will be created.

	 *

	 * @param	featureList	the feature list

	 * @see 				#NewInstance()

	 * @see 				#NewInstance(UUID)

	 */

	public static FeatureTree<Feature> NewInstance(List<Feature> featureList){

		FeatureTree<Feature> result =  new FeatureTree<>(TermType.Feature);

		FeatureNode<Feature> root = result.getRoot();

		for (Feature feature : featureList){

			FeatureNode<Feature> child = FeatureNode.NewInstance(feature);

			root.addChild(child);

		}

		return result;

	}

// ******************** CONSTRUCTOR *************************************/

    //for JAXB only, TODO needed?

    @Deprecated

    protected FeatureTree(){}

	/**

	 * Class constructor: creates a new feature tree instance with an empty

	 * {@link #getRoot() root node}.

	 */

	protected FeatureTree(TermType termType) {

        this.termType = termType;

        checkTermType(this);

		root = FeatureNode.NewInstance(termType);

		root.setFeatureTree(this);

	}

// ****************** GETTER / SETTER **********************************/

	@Override

    public TermType getTermType() {

        return termType;

    }

    /**

	 * Returns the topmost {@link FeatureNode feature node} (root node) of <i>this</i>

	 * feature tree. The root node does not have any parent. Since feature nodes

	 * recursively point to their child nodes the complete feature tree is

	 * defined by its root node.

	 */

	public FeatureNode<T> getRoot() {

		return root;

	}

    /**

     * @deprecated this method is only for internal use when deleting a {@link FeatureTree}

     * from a database. It should never be called for other reasons.

     */

    @Deprecated

    public void removeRootNode() {

        this.root = null;

    }

	/**

	 * Returns the (ordered) list of {@link FeatureNode feature nodes} which are immediate

	 * children of the root node of <i>this</i> feature tree.

	 */

	@Transient

	public List<FeatureNode<T>> getRootChildren(){

		List<FeatureNode<T>> result = new ArrayList<>();

		result.addAll(root.getChildNodes());

		return result;

	}

    public boolean isAllowDuplicates() {

        return allowDuplicates;

    }

    public void setAllowDuplicates(boolean allowDuplicates) {

        this.allowDuplicates = allowDuplicates;

    }

    /**

     * Throws {@link IllegalArgumentException} if the given

     * term has not the same term type as this term or if term type is null.

     * @param term

     */

    private void checkTermType(IHasTermType term) {

        IHasTermType.checkTermTypes(term, this);

    }

//******************** METHODS ***********************************************/

	/**

	 * Computes a set of distinct terms that are present in this feature tree

	 *

	 * @return

	 */

	@Transient

	public Set<T> getDistinctFeatures(){

	    if(termType.equals(TermType.Feature) || termType.isKindOf(TermType.Feature)){

	        Set<T> features = new HashSet<>();

	        return root.getDistinctFeaturesRecursive(features);

	    }

	    String message = "FeatureTree is not of type FEATURE.";

	    logger.warn(message, new UnexpectedException(message));

	    return new HashSet<>();

	}

//*********************** CLONE ********************************************************/

	/**

	 * Clones <i>this</i> FeatureTree. This is a shortcut that enables to create

	 * a new instance that differs only slightly from <i>this</i> FeatureTree by

	 * modifying only some of the attributes.

	 * FeatureNodes always belong only to one tree, so all FeatureNodes are cloned to build

	 * the new FeatureTree

	 *

	 *

	 * @see eu.etaxonomy.cdm.model.term.TermBase#clone()

	 * @see java.lang.Object#clone()

	 */

	@Override

	public Object clone() {

		FeatureTree<T> result;

		try {

			result = (FeatureTree<T>)super.clone();

		}catch (CloneNotSupportedException e) {

			logger.warn("Object does not implement cloneable");

			e.printStackTrace();

			return null;

		}

		FeatureNode<T> rootClone = this.getRoot().cloneDescendants();

		result.root = rootClone;

		return result;

	}

}