resource-registry/src/main/java/org/gcube/informationsystem/resourceregistry/instances/base/relations/BaseRelationManagement.java

package org.gcube.informationsystem.resourceregistry.instances.base.relations;

import java.util.UUID;

import org.gcube.informationsystem.base.reference.AccessType;
import org.gcube.informationsystem.base.reference.entities.BaseEntity;
import org.gcube.informationsystem.model.reference.relations.Relation;
import org.gcube.informationsystem.resourceregistry.api.exceptions.ResourceRegistryException;
import org.gcube.informationsystem.resourceregistry.api.exceptions.relation.RelationNotFoundException;
import org.gcube.informationsystem.resourceregistry.api.exceptions.schema.SchemaException;
import org.gcube.informationsystem.resourceregistry.contexts.SecurityContext;
import org.gcube.informationsystem.resourceregistry.instances.base.ERManagement;
import org.gcube.informationsystem.resourceregistry.instances.base.entities.BaseEntityManagement;
import org.gcube.informationsystem.resourceregistry.instances.model.entities.FacetManagement;
import org.gcube.informationsystem.resourceregistry.utils.Utility;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import com.orientechnologies.orient.core.db.document.ODatabaseDocument;
import com.orientechnologies.orient.core.record.ODirection;
import com.orientechnologies.orient.core.record.OEdge;
import com.orientechnologies.orient.core.record.OVertex;

/**
 * @author Luca Frosini (ISTI - CNR)
 */
public abstract class BaseRelationManagement<SEM extends BaseEntityManagement<? extends BaseEntity>, TEM extends BaseEntityManagement<? extends BaseEntity>>
		extends ERManagement<OEdge> {
	
	protected final Class<? extends BaseEntity> sourceEntityClass;
	protected final Class<? extends BaseEntity> targetEntityClass;
	
	protected SEM sourceEntityManagement;
	protected TEM targetEntityManagement;
	
	protected BaseRelationManagement(AccessType accessType, Class<? extends BaseEntity> sourceEntityClass, Class<? extends BaseEntity> targetEntityClass) {
		super(accessType);
		
		this.ignoreKeys.add(Relation.HEADER_PROPERTY);
		this.ignoreKeys.add(Relation.SOURCE_PROPERTY);
		this.ignoreKeys.add(Relation.TARGET_PROPERTY);
		this.ignoreKeys.add(com.tinkerpop.blueprints.impls.orient.OrientBaseGraph.CONNECTION_OUT.toLowerCase());
		this.ignoreKeys.add(com.tinkerpop.blueprints.impls.orient.OrientBaseGraph.CONNECTION_IN.toLowerCase());
		this.ignoreKeys.add(com.tinkerpop.blueprints.impls.orient.OrientBaseGraph.CONNECTION_OUT.toUpperCase());
		this.ignoreKeys.add(com.tinkerpop.blueprints.impls.orient.OrientBaseGraph.CONNECTION_IN.toUpperCase());
		
		this.sourceEntityClass = sourceEntityClass;
		this.targetEntityClass = targetEntityClass;
		
		this.sourceEntityManagement = null;
		this.targetEntityManagement = null;
	}
	
	protected BaseRelationManagement(AccessType accessType, Class<? extends BaseEntity> sourceEntityClass, Class<? extends BaseEntity> targetEntityClass, SecurityContext workingContext, ODatabaseDocument orientGraph) {
		this(accessType, sourceEntityClass, targetEntityClass);
		this.oDatabaseDocument = orientGraph;
		setWorkingContext(workingContext);
	}
	
	public SEM getSourceEntityManagement() throws ResourceRegistryException {
		if(sourceEntityManagement == null) {
			OVertex source = getElement().getVertex(ODirection.OUT);
			sourceEntityManagement = newSourceEntityManagement();
			sourceEntityManagement.setElement(source);
		}
		sourceEntityManagement.setReload(reload);
		return sourceEntityManagement;
	}
	
	public TEM getTargetEntityManagement() throws ResourceRegistryException {
		if(targetEntityManagement == null) {
			OVertex target = getElement().getVertex(ODirection.IN);
			targetEntityManagement = newTargetEntityManagement();
			targetEntityManagement.setElement(target);
		}
		targetEntityManagement.setReload(reload);
		return targetEntityManagement;
	}
	
	public void setSourceEntityManagement(SEM sourceEntityManagement) {
		this.sourceEntityManagement = sourceEntityManagement;
	}
	
	public void setTargetEntityManagement(TEM targetEntityManagement) {
		this.targetEntityManagement = targetEntityManagement;
	}
	
	@Override
	public String serialize() throws ResourceRegistryException {
		return serializeAsJson().toString();
	}
	
	@Override
	public JsonNode serializeAsJson() throws ResourceRegistryException {
		return serializeAsJson(true, true);
	}
	
	public JsonNode serializeAsJson(boolean includeSource, boolean includeTarget) throws ResourceRegistryException {
		JsonNode relation = serializeSelfOnly();
		
		try {
			if(includeSource) {
				BaseEntityManagement<? extends BaseEntity> sourceEntityManagement = getSourceEntityManagement();
				((ObjectNode) relation).replace(Relation.SOURCE_PROPERTY, sourceEntityManagement.serializeSelfOnly());
			}
			
			if(includeTarget) {
				BaseEntityManagement<? extends BaseEntity> targetEntityManagement = getTargetEntityManagement();
				((ObjectNode) relation).replace(Relation.TARGET_PROPERTY, targetEntityManagement.serializeAsJson());
			}
			
		} catch(ResourceRegistryException e) {
			logger.error("Unable to correctly serialize {}. {}", element, Utility.SHOULD_NOT_OCCUR_ERROR_MESSAGE, e);
			throw e;
		} catch(Exception e) {
			logger.error("Unable to correctly serialize {}. {}", element, Utility.SHOULD_NOT_OCCUR_ERROR_MESSAGE, e);
			throw new ResourceRegistryException(e);
		}
		
		return relation;
	}
	
	@Override
	protected OEdge reallyCreate() throws ResourceRegistryException {
		
		if(sourceEntityManagement == null) {
			
			if(!jsonNode.has(Relation.SOURCE_PROPERTY)) {
				throw new ResourceRegistryException("Error while creating relation. No source definition found");
			}
			
			UUID sourceUUID = org.gcube.informationsystem.utils.Utility
					.getUUIDFromJsonNode(jsonNode.get(Relation.SOURCE_PROPERTY));
			
			sourceEntityManagement = newSourceEntityManagement();
			sourceEntityManagement.setUUID(sourceUUID);
		}
		
		if(targetEntityManagement == null) {
			targetEntityManagement = newTargetEntityManagement();
			
			if(!jsonNode.has(Relation.TARGET_PROPERTY)) {
				throw new ResourceRegistryException(
						"Error while creating " + elementType + ". No target definition found");
			}
			
			try {
				targetEntityManagement.setJsonNode(jsonNode.get(Relation.TARGET_PROPERTY));
			} catch(SchemaException e) {
				StringBuilder errorMessage = new StringBuilder();
				errorMessage.append("A ");
				errorMessage.append(elementType);
				errorMessage.append(" can be only created beetween ");
				errorMessage.append(sourceEntityManagement.getAccessType().getName());
				errorMessage.append(" and ");
				errorMessage.append(targetEntityManagement.getAccessType().getName());
				throw new ResourceRegistryException(errorMessage.toString(), e);
			}
			
			try {
				targetEntityManagement.getElement();
			} catch(Exception e) {
				targetEntityManagement.internalCreate();
			}
		}
		
		logger.trace("Creating {} beetween {} -> {}", elementType, getSourceEntityManagement().serialize(),
				getTargetEntityManagement().serialize());
		
		OVertex source = (OVertex) getSourceEntityManagement().getElement();
		OVertex target = (OVertex) getTargetEntityManagement().getElement();
		
		element = oDatabaseDocument.newEdge(source, target, elementType);
		
		ERManagement.updateProperties(oClass, element, jsonNode, ignoreKeys, ignoreStartWithKeys);
		
		return element;
	}
	
	protected abstract SEM newSourceEntityManagement() throws ResourceRegistryException;
	
	protected abstract TEM newTargetEntityManagement() throws ResourceRegistryException;
	
	@Override
	protected OEdge reallyUpdate() throws ResourceRegistryException {
		
		logger.debug("Trying to update {} : {}", elementType, jsonNode);
		
		OEdge edge = getElement();
		ERManagement.updateProperties(oClass, edge, jsonNode, ignoreKeys, ignoreStartWithKeys);
		
		if(accessType.compareTo(AccessType.CONSISTS_OF) == 0) {
			JsonNode target = jsonNode.get(Relation.TARGET_PROPERTY);
			if(target != null) {
				FacetManagement fm = new FacetManagement(getWorkingContext(), oDatabaseDocument);
				fm.setJsonNode(target);
				fm.internalUpdate();
			}
		}
		
		logger.info("{} {} successfully updated", elementType, jsonNode);
		
		return edge;
		
	}
	
	@Override
	protected boolean reallyDelete() throws RelationNotFoundException, ResourceRegistryException {
		logger.debug("Going to remove {} with UUID {}. Related {}s will be detached.", accessType.getName(), uuid,
				targetEntityClass.getSimpleName());
		
		getElement().delete();
		
		return true;
	}
	
}