package de.mpiwg.itgroup.ismi.auxObjects;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import javax.faces.model.SelectItem;

import org.mpi.openmind.repository.bo.Attribute;
import org.mpi.openmind.repository.bo.Entity;

/**
 * ListenerObject that searches in Entity Attributes and ALIASes connected by a given Relation. 
 * 
 * @author casties
 *
 */
public class AliasListenerObject extends ListenerObject {

    private static final long serialVersionUID = 2072530246758155955L;
    
    public String aliasRelName;
    
    /**
     * ListenerObject that searches in Entity Attributes and also in ALIASes connected by a given Relation.
     * 
     * Uses relation ALIAS - aliasRelName -> ENTITY (usually "is_alias_name_of").
     * 
     * @param classObj
     * @param attName
     * @param aliasRelName
     */
    public AliasListenerObject(String classObj, String attName, String aliasRelName) {
        super(classObj, attName);
        this.aliasRelName = aliasRelName;
    }

    /**
     * Sets the current entity and displays the selected attribute if it is not already set.
     * This is meant not to overwrite an entity already set by an alias.
     * 
     * @see de.mpiwg.itgroup.ismi.auxObjects.ListenerObject#setEntityAndAttribute(org.mpi.openmind.repository.bo.Entity)
     */
    public void setEntityAndAttributeIfEmpty(Entity ent) {
        if ((this.entity == null) || (this.entity.getObjectClass() == null)) {
            super.setEntityAndAttribute(ent);
        }
    }

    /* (non-Javadoc)
     * @see de.mpiwg.itgroup.ismi.auxObjects.AbstractListenerObject#updateSuggestedItems(java.lang.String, java.lang.String, java.lang.String)
     */
    @Override
    protected List<SelectItem> updateSuggestedItems(String searchWord, String objClass, String attName) {

        // find matching entity attributes
        List<Attribute> attList = getWrapper().getAttributesByDefByAttName(objClass, attName, searchWord.toString(), MAX_SUGGEST);
        
        // find all matching aliases
        List<Attribute> aliasAtts = getWrapper().getAttributesByDefByAttName("ALIAS", "alias", searchWord.toString(), 0);
        // filter related aliases
        int aliasCnt = 0;
        for (Attribute att : aliasAtts) {
            Long aliasId = att.getSourceId();
            // find the Entities with the correct Relation
            List<Entity> ents = getWrapper().getTargetsForSourceRelation(aliasId, aliasRelName, objClass, 1);
            if (!ents.isEmpty()) {
                // ALIAS is related to Entity
                attList.add(att);
                aliasCnt += 1;
                if (aliasCnt > MAX_SUGGEST) {
                    break;
                }
            }
        }
        if (aliasCnt > 0) {
            // re-sort with added aliases
            Collections.sort(attList);
        }
        
        List<SelectItem> suggestedItems = new ArrayList<SelectItem>();
        if (attList == null)
            return suggestedItems;

        for (Attribute att : attList) {
            String label = att.getOwnValue();
            if (att.getSourceObjectClass().equals("ALIAS")) {
                label += " [ALIAS " + att.getSourceId() + "]";
            } else {
                label += " [" + att.getSourceId() + "]";                
            }
            SelectItem item = new SelectItem(att, label, "description: " + att);
            suggestedItems.add(item);
        }
        return suggestedItems;
    }

    /**
     * @return the aliasRelName
     */
    public String getAliasRelName() {
        return aliasRelName;
    }

    /**
     * @param aliasRelName the aliasRelName to set
     */
    public void setAliasRelName(String aliasRelName) {
        this.aliasRelName = aliasRelName;
    }

}