/*-
 * ============LICENSE_START=======================================================
 * SDC
 * ================================================================================
 * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ============LICENSE_END=========================================================
 */
package org.openecomp.sdc.be.dao.janusgraph;

import static org.apache.commons.collections.CollectionUtils.isEmpty;

import fj.data.Either;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.EnumMap;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Optional;
import java.util.function.Predicate;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;
import lombok.Getter;
import org.apache.commons.collections.MapUtils;
import org.apache.commons.collections4.CollectionUtils;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.lang3.tuple.ImmutablePair;
import org.apache.tinkerpop.gremlin.structure.Direction;
import org.apache.tinkerpop.gremlin.structure.Edge;
import org.apache.tinkerpop.gremlin.structure.Element;
import org.apache.tinkerpop.gremlin.structure.Property;
import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.apache.tinkerpop.gremlin.structure.util.ElementHelper;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphEdge;
import org.janusgraph.core.JanusGraphQuery;
import org.janusgraph.core.JanusGraphVertex;
import org.janusgraph.core.JanusGraphVertexQuery;
import org.janusgraph.core.PropertyKey;
import org.janusgraph.graphdb.query.JanusGraphPredicate;
import org.openecomp.sdc.be.dao.api.exception.JanusGraphException;
import org.openecomp.sdc.be.dao.jsongraph.GraphVertex;
import org.openecomp.sdc.be.dao.jsongraph.types.EdgeLabelEnum;
import org.openecomp.sdc.be.dao.jsongraph.types.EdgePropertyEnum;
import org.openecomp.sdc.be.dao.jsongraph.types.JsonParseFlagEnum;
import org.openecomp.sdc.be.dao.jsongraph.types.VertexTypeEnum;
import org.openecomp.sdc.be.dao.jsongraph.utils.JsonParserUtils;
import org.openecomp.sdc.be.dao.neo4j.GraphEdgeLabels;
import org.openecomp.sdc.be.datatypes.enums.ComponentTypeEnum;
import org.openecomp.sdc.be.datatypes.enums.GraphPropertyEnum;
import org.openecomp.sdc.be.datatypes.enums.ModelTypeEnum;
import org.openecomp.sdc.be.datatypes.tosca.ToscaDataDefinition;
import org.openecomp.sdc.common.jsongraph.util.CommonUtility;
import org.openecomp.sdc.common.jsongraph.util.CommonUtility.LogLevelEnum;
import org.openecomp.sdc.common.log.enums.EcompLoggerErrorCode;
import org.openecomp.sdc.common.log.wrappers.Logger;
import org.springframework.beans.factory.annotation.Qualifier;

public class JanusGraphDao {

    private static final Logger logger = Logger.getLogger(JanusGraphDao.class);
    private static final String FAILED_TO_GET_BY_CRITERIA_FOR_TYPE_AND_PROPERTIES = "Failed to get by criteria for type '{}' and properties '{}'";
    @Getter
    private final JanusGraphClient janusGraphClient;

    public JanusGraphDao(@Qualifier("janusgraph-client") JanusGraphClient janusGraphClient) {
        this.janusGraphClient = janusGraphClient;
        logger.info("** JanusGraphDao created");
    }

    public JanusGraphOperationStatus commit() {
        logger.debug("#commit - The operation succeeded. Doing commit...");
        return janusGraphClient.commit();
    }

    public JanusGraphOperationStatus rollback() {
        logger.debug("#rollback - The operation failed. Doing rollback...");
        return janusGraphClient.rollback();
    }

    /**
     * @param graphVertex
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> createVertex(GraphVertex graphVertex) {
        logger.trace("try to create vertex for ID [{}]", graphVertex.getUniqueId());
        Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (graph.isLeft()) {
            try {
                JanusGraph tGraph = graph.left().value();
                JanusGraphVertex vertex = tGraph.addVertex();
                setVertexProperties(vertex, graphVertex);
                graphVertex.setVertex(vertex);
                return Either.left(graphVertex);
            } catch (Exception e) {
                logger
                    .error(EcompLoggerErrorCode.DATA_ERROR, "JanusGraphDao", "Failed to create Node for ID '{}'", (Object) graphVertex.getUniqueId(),
                        e);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("Failed to create vertex for ID '{}' {}", graphVertex.getUniqueId(), graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    /**
     * @param name
     * @param value
     * @param label
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> getVertexByPropertyAndLabel(GraphPropertyEnum name, Object value, VertexTypeEnum label) {
        return getVertexByPropertyAndLabel(name, value, label, JsonParseFlagEnum.ParseAll);
    }

    public Either<GraphVertex, JanusGraphOperationStatus> getVertexByLabel(VertexTypeEnum label) {
        return janusGraphClient.getGraph().left().map(graph -> graph.query().has(GraphPropertyEnum.LABEL.getProperty(), label.getName()).vertices())
            .left().bind(janusGraphVertices -> getFirstFoundVertex(JsonParseFlagEnum.NoParse, janusGraphVertices));
    }

    private Either<GraphVertex, JanusGraphOperationStatus> getFirstFoundVertex(JsonParseFlagEnum parseFlag, Iterable<JanusGraphVertex> vertices) {
        Iterator<JanusGraphVertex> iterator = vertices.iterator();
        if (iterator.hasNext()) {
            JanusGraphVertex vertex = iterator.next();
            GraphVertex graphVertex = createAndFill(vertex, parseFlag);
            return Either.left(graphVertex);
        }
        return Either.right(JanusGraphOperationStatus.NOT_FOUND);
    }

    /**
     * @param name
     * @param value
     * @param label
     * @param parseFlag
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> getVertexByPropertyAndLabel(GraphPropertyEnum name, Object value, VertexTypeEnum label,
                                                                                      JsonParseFlagEnum parseFlag) {
        Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (graph.isLeft()) {
            try {
                JanusGraph tGraph = graph.left().value();
                @SuppressWarnings("unchecked") Iterable<JanusGraphVertex> vertices = tGraph.query().has(name.getProperty(), value)
                    .has(GraphPropertyEnum.LABEL.getProperty(), label.getName()).vertices();
                java.util.Iterator<JanusGraphVertex> iterator = vertices.iterator();
                if (iterator.hasNext()) {
                    JanusGraphVertex vertex = iterator.next();
                    GraphVertex graphVertex = createAndFill(vertex, parseFlag);
                    return Either.left(graphVertex);
                }
                logger.debug("No vertex in graph for key = {}  and value = {}   label = {}", name, value, label);
                return Either.right(JanusGraphOperationStatus.NOT_FOUND);
            } catch (Exception e) {
                logger.debug("Failed to get vertex in graph for key ={} and value = {}  label = {}", name, value, label);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("No vertex in graph for key ={} and value = {}  label = {} error :{}", name, value, label, graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    /**
     * @param id
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> getVertexById(String id) {
        return getVertexById(id, JsonParseFlagEnum.ParseAll);
    }

    /**
     * @param id
     * @param parseFlag
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> getVertexById(String id, JsonParseFlagEnum parseFlag) {
        Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (id == null) {
            logger.debug("No vertex in graph for id = {} ", id);
            return Either.right(JanusGraphOperationStatus.NOT_FOUND);
        }
        if (graph.isLeft()) {
            try {
                JanusGraph tGraph = graph.left().value();
                @SuppressWarnings("unchecked") Iterable<JanusGraphVertex> vertices = tGraph.query()
                    .has(GraphPropertyEnum.UNIQUE_ID.getProperty(), id).vertices();
                java.util.Iterator<JanusGraphVertex> iterator = vertices.iterator();
                if (iterator.hasNext()) {
                    JanusGraphVertex vertex = iterator.next();
                    GraphVertex graphVertex = createAndFill(vertex, parseFlag);
                    return Either.left(graphVertex);
                } else {
                    logger.debug("No vertex in graph for id = {}", id);
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }
            } catch (Exception e) {
                logger.debug("Failed to get vertex in graph for id {} ", id);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("No vertex in graph for id {} error : {}", id, graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    private void setVertexProperties(JanusGraphVertex vertex, GraphVertex graphVertex) throws IOException {
        if (graphVertex.getMetadataProperties() != null) {
            for (Map.Entry<GraphPropertyEnum, Object> entry : graphVertex.getMetadataProperties().entrySet()) {
                if (entry.getValue() != null) {
                    vertex.property(entry.getKey().getProperty(), entry.getValue());
                }
            }
        }
        vertex.property(GraphPropertyEnum.LABEL.getProperty(), graphVertex.getLabel().getName());
        Map<String, ? extends ToscaDataDefinition> json = graphVertex.getJson();
        if (json != null) {
            String jsonStr = JsonParserUtils.toJson(json);
            vertex.property(GraphPropertyEnum.JSON.getProperty(), jsonStr);
        }
        Map<String, Object> jsonMetadata = graphVertex.getMetadataJson();
        if (jsonMetadata != null) {
            String jsonMetadataStr = JsonParserUtils.toJson(jsonMetadata);
            vertex.property(GraphPropertyEnum.METADATA.getProperty(), jsonMetadataStr);
        }
    }

    public void setVertexProperties(Vertex vertex, Map<String, Object> properties) {
        for (Map.Entry<String, Object> entry : properties.entrySet()) {
            if (entry.getValue() != null) {
                vertex.property(entry.getKey(), entry.getValue());
            }
        }
    }

    private GraphVertex createAndFill(JanusGraphVertex vertex, JsonParseFlagEnum parseFlag) {
        GraphVertex graphVertex = new GraphVertex();
        graphVertex.setVertex(vertex);
        parseVertexProperties(graphVertex, parseFlag);
        return graphVertex;
    }

    public void parseVertexProperties(GraphVertex graphVertex, JsonParseFlagEnum parseFlag) {
        JanusGraphVertex vertex = graphVertex.getVertex();
        Map<GraphPropertyEnum, Object> properties = getVertexProperties(vertex);
        VertexTypeEnum label = VertexTypeEnum.getByName((String) (properties.get(GraphPropertyEnum.LABEL)));
        for (Map.Entry<GraphPropertyEnum, Object> entry : properties.entrySet()) {
            GraphPropertyEnum key = entry.getKey();
            switch (key) {
                case UNIQUE_ID:
                    graphVertex.setUniqueId((String) entry.getValue());
                    break;
                case LABEL:
                    graphVertex.setLabel(VertexTypeEnum.getByName((String) entry.getValue()));
                    break;
                case COMPONENT_TYPE:
                    String type = (String) entry.getValue();
                    if (type != null) {
                        graphVertex.setType(ComponentTypeEnum.valueOf(type));
                    }
                    break;
                case JSON:
                    if (parseFlag == JsonParseFlagEnum.ParseAll || parseFlag == JsonParseFlagEnum.ParseJson) {
                        String json = (String) entry.getValue();
                        Map<String, ? extends ToscaDataDefinition> jsonObj = JsonParserUtils.toMap(json, label.getClassOfJson());
                        graphVertex.setJson(jsonObj);
                    }
                    break;
                case METADATA:
                    if (parseFlag == JsonParseFlagEnum.ParseAll || parseFlag == JsonParseFlagEnum.ParseMetadata) {
                        String json = (String) entry.getValue();
                        Map<String, Object> metadatObj = JsonParserUtils.toMap(json);
                        graphVertex.setMetadataJson(metadatObj);
                    }
                    break;
                default:
                    graphVertex.addMetadataProperty(key, entry.getValue());
                    break;
            }
        }
    }

    public JanusGraphOperationStatus createEdge(GraphVertex from, GraphVertex to, EdgeLabelEnum label, Map<EdgePropertyEnum, Object> properties) {
        return createEdge(from.getVertex(), to.getVertex(), label, properties);
    }

    public JanusGraphOperationStatus createEdge(Vertex from, Vertex to, EdgeLabelEnum label, Map<EdgePropertyEnum, Object> properties) {
        logger.trace("Try to connect {} with {} label {} properties {}",
            from == null ? "NULL" : from.property(GraphPropertyEnum.UNIQUE_ID.getProperty()),
            to == null ? "NULL" : to.property(GraphPropertyEnum.UNIQUE_ID.getProperty()), label, properties);
        if (from == null || to == null) {
            logger.trace("No JanusGraph vertex for id from {} or id to {}",
                from == null ? "NULL" : from.property(GraphPropertyEnum.UNIQUE_ID.getProperty()),
                to == null ? "NULL" : to.property(GraphPropertyEnum.UNIQUE_ID.getProperty()));
            return JanusGraphOperationStatus.NOT_FOUND;
        }
        Edge edge = from.addEdge(label.name(), to);
        JanusGraphOperationStatus status;
        try {
            setEdgeProperties(edge, properties);
            status = JanusGraphOperationStatus.OK;
        } catch (IOException e) {
            logger.error(EcompLoggerErrorCode.DATA_ERROR, "JanusGraphDao", "Failed to set properties on edge  properties [{}]", properties, e);
            status = JanusGraphOperationStatus.GENERAL_ERROR;
        }
        return status;
    }

    public Map<GraphPropertyEnum, Object> getVertexProperties(Element element) {
        Map<GraphPropertyEnum, Object> result = new HashMap<>();
        if (element != null && CollectionUtils.isNotEmpty(element.keys())) {
            Map<String, Property> propertyMap = ElementHelper.propertyMap(element, element.keys().toArray(new String[element.keys().size()]));
            for (Entry<String, Property> entry : propertyMap.entrySet()) {
                String key = entry.getKey();
                Object value = entry.getValue().value();
                GraphPropertyEnum valueOf = GraphPropertyEnum.getByProperty(key);
                if (valueOf != null) {
                    result.put(valueOf, value);
                }
            }
            // add print to properties that can't be converted by enum
        }
        return result;
    }

    public Map<EdgePropertyEnum, Object> getEdgeProperties(Element element) {
        Map<EdgePropertyEnum, Object> result = new HashMap<>();
        if (element != null && CollectionUtils.isNotEmpty(element.keys())) {
            Map<String, Property> propertyMap = ElementHelper.propertyMap(element, element.keys().toArray(new String[element.keys().size()]));
            for (Entry<String, Property> entry : propertyMap.entrySet()) {
                String key = entry.getKey();
                Object value = entry.getValue().value();
                EdgePropertyEnum valueOf = EdgePropertyEnum.getByProperty(key);
                if (valueOf != null) {
                    if (valueOf == EdgePropertyEnum.INSTANCES) {
                        List<String> list = JsonParserUtils.toList((String) value, String.class);
                        result.put(valueOf, list);
                    } else {
                        result.put(valueOf, value);
                    }
                }
            }
        }
        return result;
    }

    public void setEdgeProperties(Element element, Map<EdgePropertyEnum, Object> properties) throws IOException {
        if (properties != null && !properties.isEmpty()) {
            Object[] propertyKeyValues = new Object[properties.size() * 2];
            int i = 0;
            for (Entry<EdgePropertyEnum, Object> entry : properties.entrySet()) {
                propertyKeyValues[i++] = entry.getKey().getProperty();
                Object value = entry.getValue();
                if (entry.getKey() == EdgePropertyEnum.INSTANCES) {
                    String jsonStr = JsonParserUtils.toJson(value);
                    propertyKeyValues[i++] = jsonStr;
                } else {
                    propertyKeyValues[i++] = entry.getValue();
                }
            }
            ElementHelper.attachProperties(element, propertyKeyValues);
        }
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(VertexTypeEnum type, Map<GraphPropertyEnum, Object> props) {
        return getByCriteria(type, props, JsonParseFlagEnum.ParseAll);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(VertexTypeEnum type, Map<GraphPropertyEnum, Object> props,
                                                                              JsonParseFlagEnum parseFlag) {
        Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (graph.isLeft()) {
            try {
                JanusGraph tGraph = graph.left().value();
                JanusGraphQuery<? extends JanusGraphQuery> query = tGraph.query();
                if (type != null) {
                    query = query.has(GraphPropertyEnum.LABEL.getProperty(), type.getName());
                }
                if (props != null && !props.isEmpty()) {
                    for (Map.Entry<GraphPropertyEnum, Object> entry : props.entrySet()) {
                        query = query.has(entry.getKey().getProperty(), entry.getValue());
                    }
                }
                Iterable<JanusGraphVertex> vertices = query.vertices();
                if (vertices == null) {
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }
                Iterator<JanusGraphVertex> iterator = vertices.iterator();
                List<GraphVertex> result = new ArrayList<>();
                while (iterator.hasNext()) {
                    JanusGraphVertex vertex = iterator.next();
                    getVertexProperties(vertex);
                    GraphVertex graphVertex = createAndFill(vertex, parseFlag);
                    result.add(graphVertex);
                }
                logger.debug("Number of fetched nodes in graph for criteria : from type = {} and properties = {} is {}", type, props, result.size());
                if (result.size() == 0) {
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }
                return Either.left(result);
            } catch (Exception e) {
                logger.debug("Failed get by criteria for type = {} and properties = {}", type, props, e);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("Failed  get by  criteria for type ={} and properties = {} error : {}", type, props, graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(final VertexTypeEnum type, final Map<GraphPropertyEnum, Object> props,
                                                                              final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              final JsonParseFlagEnum parseFlag,
                                                                              final String model) {
        return getByCriteria(type, props, hasNotProps, null, parseFlag, model, false);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(final VertexTypeEnum type, final Map<GraphPropertyEnum, Object> props,
                                                                              final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              final JsonParseFlagEnum parseFlag,
                                                                              final String model,
                                                                              final boolean includeNormativeExtensionModels) {
        return getByCriteria(type, props, hasNotProps, null, parseFlag, model, includeNormativeExtensionModels);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(final VertexTypeEnum type,
                                                                              final Map<GraphPropertyEnum, Object> hasProps,
                                                                              final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              final Map<String, Entry<JanusGraphPredicate, Object>> predicates,
                                                                              final JsonParseFlagEnum parseFlag,
                                                                              final String model) {
        return getByCriteria(type, hasProps, hasNotProps, predicates, parseFlag, model, false);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(final VertexTypeEnum type,
                                                                              final Map<GraphPropertyEnum, Object> hasProps,
                                                                              final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              final Map<String, Entry<JanusGraphPredicate, Object>> predicates,
                                                                              final JsonParseFlagEnum parseFlag,
                                                                              final String model,
                                                                              final boolean includeNormativeExtensionModels) {
        Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (graph.isLeft()) {
            try {
                JanusGraphQuery<? extends JanusGraphQuery> query = getJanusGraphQuery(type, hasProps, hasNotProps, predicates, graph.left().value());
                final Iterable<JanusGraphVertex> vertices = query.vertices();
                if (vertices == null || !vertices.iterator().hasNext()) {
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }

                final Predicate<? super JanusGraphVertex> filterPredicate = StringUtils.isEmpty(model) ? this::vertexNotConnectedToAnyModel
                    : vertex -> vertexValidForModel(vertex, model, includeNormativeExtensionModels);
                final List<JanusGraphVertex> verticesForModel = StreamSupport.stream(vertices.spliterator(), false).filter(filterPredicate)
                    .collect(Collectors.toList());
                if (CollectionUtils.isEmpty(verticesForModel)) {
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }

                final List<GraphVertex> result = new ArrayList<>();
                verticesForModel.forEach(vertex -> result.add(createAndFill(vertex, parseFlag)));
                logger.debug("Number of fetched nodes in graph for criteria : from type '{}' and properties '{}' is '{}'", type, hasProps,
                    result.size());
                return Either.left(result);
            } catch (Exception e) {
                logger.debug(FAILED_TO_GET_BY_CRITERIA_FOR_TYPE_AND_PROPERTIES, type, hasProps, e);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("Failed to get by criteria for type '{}' and properties '{}'. Error : '{}'", type, hasProps, graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(VertexTypeEnum type,
                                                                              Map<GraphPropertyEnum, Object> props,
                                                                              Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              JsonParseFlagEnum parseFlag) {
        return getByCriteria(type, props, hasNotProps, null, parseFlag);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getByCriteria(final VertexTypeEnum type,
                                                                              final Map<GraphPropertyEnum, Object> hasProps,
                                                                              final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                              final Map<String, Entry<JanusGraphPredicate, Object>> predicates,
                                                                              final JsonParseFlagEnum parseFlag) {
        final Either<JanusGraph, JanusGraphOperationStatus> graph = janusGraphClient.getGraph();
        if (graph.isLeft()) {
            try {
                JanusGraphQuery<? extends JanusGraphQuery> query = getJanusGraphQuery(type, hasProps, hasNotProps, predicates, graph.left().value());
                Iterable<JanusGraphVertex> vertices = query.vertices();
                if (vertices == null || !vertices.iterator().hasNext()) {
                    return Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }
                List<GraphVertex> result = new ArrayList<>();
                vertices.forEach(vertex -> result.add(createAndFill(vertex, parseFlag)));
                logger.debug("Number of fetched nodes in graph for criteria : from type '{}' and properties '{}' is '{}'", type, hasProps,
                    result.size());
                return Either.left(result);
            } catch (Exception e) {
                logger.debug(FAILED_TO_GET_BY_CRITERIA_FOR_TYPE_AND_PROPERTIES, type, hasProps, e);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("Failed to get by criteria for type '{}' and properties '{}'. Error : '{}'", type, hasProps, graph.right().value());
            return Either.right(graph.right().value());
        }
    }

    /**
     * Finds the vertices that have the given invariant id and any additional property provided.
     *
     * @param invariantUuid               the invariant uuid
     * @param additionalPropertiesToMatch any additional property to match along with the {@link GraphPropertyEnum#INVARIANT_UUID}
     * @return the list of vertex that has the given invariant uuid
     * @throws JanusGraphException if the find operation was returned an error status
     */
    public List<GraphVertex> findAllVertexByInvariantUuid(final String invariantUuid,
                                                          final Map<GraphPropertyEnum, Object> additionalPropertiesToMatch) {
        final Map<GraphPropertyEnum, Object> propertiesToMatch = new EnumMap<>(GraphPropertyEnum.class);
        if (MapUtils.isNotEmpty(additionalPropertiesToMatch)) {
            propertiesToMatch.putAll(additionalPropertiesToMatch);
        }
        propertiesToMatch.put(GraphPropertyEnum.INVARIANT_UUID, invariantUuid);
        final Either<List<GraphVertex>, JanusGraphOperationStatus> vertexEither =
            getByCriteria(null, propertiesToMatch, JsonParseFlagEnum.ParseMetadata);
        if (vertexEither.isRight()) {
            final JanusGraphOperationStatus status = vertexEither.right().value();
            if (status == JanusGraphOperationStatus.NOT_FOUND) {
                return Collections.emptyList();
            }
            final String errorMsg = String.format("Couldn't fetch vertex with invariantUUId '%s'. Status was '%s'", invariantUuid, status);
            throw new JanusGraphException(status, errorMsg);
        }
        final List<GraphVertex> vertices = vertexEither.left().value();
        if (vertices == null || vertices.isEmpty()) {
            return Collections.emptyList();
        }
        return vertices;
    }

    private boolean vertexValidForModel(final JanusGraphVertex vertex, final String model, final boolean includeNormativeExtensions) {
        final String vertexLabel = (String) vertex.property(GraphPropertyEnum.LABEL.getProperty()).value();
        final VertexTypeEnum vertexType = VertexTypeEnum.getByName(vertexLabel);
        final GraphEdgeLabels edgeLabel = VertexTypeEnum.TOPOLOGY_TEMPLATE.equals(vertexType) ? GraphEdgeLabels.MODEL : GraphEdgeLabels.MODEL_ELEMENT;
        final Either<List<ImmutablePair<JanusGraphVertex, Edge>>, JanusGraphOperationStatus> modelVertices = getParentVertices(vertex, edgeLabel);

        return modelVertices.isLeft() && modelVertices.left().value().stream()
            .anyMatch(vertexPair -> modelVertexMatchesModel(vertexPair.getLeft(), model, includeNormativeExtensions));
    }

    private boolean modelVertexMatchesModel(final JanusGraphVertex modelVertex, final String model, final boolean includeNormativeExtensions) {
        if (model.equals((String) modelVertex.property("name").value())) {
            return true;
        }
        final Either<List<ImmutablePair<JanusGraphVertex, Edge>>, JanusGraphOperationStatus> derivedModels =
            getParentVertices(modelVertex, GraphEdgeLabels.DERIVED_FROM);
        if (derivedModels.isLeft() && derivedModels.left().value().stream()
            .anyMatch(derivedModel -> modelVertexMatchesModel(derivedModel.left, model, includeNormativeExtensions))) {
            return true;
        }

        if (includeNormativeExtensions && isANormativeExtension(modelVertex)) {
            final Either<List<Vertex>, JanusGraphOperationStatus> derivedFromModels =
                getChildrenVertices(modelVertex, EdgeLabelEnum.DERIVED_FROM);
            return derivedFromModels.isLeft() && derivedFromModels.left().value().stream()
                .anyMatch(derivedFromModel -> model.equals((String) derivedFromModel.property("name").value()));
        }
        return false;
    }

    private boolean isANormativeExtension(final JanusGraphVertex modelVertex) {
        return ModelTypeEnum.NORMATIVE_EXTENSION.getValue().equals((String) modelVertex.property(GraphPropertyEnum.MODEL_TYPE.getProperty()).value());
    }

    private Either<List<ImmutablePair<JanusGraphVertex, Edge>>, JanusGraphOperationStatus> getParentVertices(
        final JanusGraphVertex rootVertex, final GraphEdgeLabels edgeType) {
        return getEdgeVertices(rootVertex, Direction.IN, edgeType);
    }

    private Either<List<ImmutablePair<JanusGraphVertex, Edge>>, JanusGraphOperationStatus> getEdgeVertices(
        final JanusGraphVertex rootVertex, final Direction direction, final GraphEdgeLabels edgeType) {
        final List<ImmutablePair<JanusGraphVertex, Edge>> immutablePairs = new ArrayList<>();
        final Iterator<Edge> edgesCreatorIterator = rootVertex.edges(direction, edgeType.getProperty());
        if (edgesCreatorIterator != null) {
            while (edgesCreatorIterator.hasNext()) {
                Edge edge = edgesCreatorIterator.next();
                JanusGraphVertex vertex = Direction.OUT.equals(direction) ? (JanusGraphVertex) edge.inVertex() : (JanusGraphVertex) edge.outVertex();
                ImmutablePair<JanusGraphVertex, Edge> immutablePair = new ImmutablePair<>(vertex, edge);
                immutablePairs.add(immutablePair);
            }
        }
        if (immutablePairs.isEmpty()) {
            return Either.right(JanusGraphOperationStatus.NOT_FOUND);
        }
        return Either.left(immutablePairs);
    }

    private boolean vertexNotConnectedToAnyModel(final JanusGraphVertex vertex) {
        String vt = (String) vertex.property(GraphPropertyEnum.LABEL.getProperty()).value();
        VertexTypeEnum vertexType = VertexTypeEnum.getByName(vt);
        EdgeLabelEnum edgeLabel = VertexTypeEnum.TOPOLOGY_TEMPLATE.equals(vertexType) ? EdgeLabelEnum.MODEL : EdgeLabelEnum.MODEL_ELEMENT;
        return !vertex.edges(Direction.IN, edgeLabel.name()).hasNext();
    }

    public Either<Iterator<Vertex>, JanusGraphOperationStatus> getCatalogOrArchiveVertices(boolean isCatalog) {
        Either<JanusGraph, JanusGraphOperationStatus> graphEither = janusGraphClient.getGraph();
        if (graphEither.isLeft()) {
            try {
                JanusGraph graph = graphEither.left().value();
                String vertexType = isCatalog ? VertexTypeEnum.CATALOG_ROOT.getName() : VertexTypeEnum.ARCHIVE_ROOT.getName();
                Iterable<JanusGraphVertex> vertexIterable = graph.query().has(GraphPropertyEnum.LABEL.getProperty(), vertexType).vertices();
                if (vertexIterable == null) {
                    logger.debug("Failed to fetch catalog vertex");
                    return Either.right(JanusGraphOperationStatus.GENERAL_ERROR);
                }
                JanusGraphVertex catalogVertex = vertexIterable.iterator().next();
                if (catalogVertex == null) {
                    logger.debug("Failed to fetch catalog vertex");
                    return Either.right(JanusGraphOperationStatus.GENERAL_ERROR);
                }
                String edgeLabel = isCatalog ? EdgeLabelEnum.CATALOG_ELEMENT.name() : EdgeLabelEnum.ARCHIVE_ELEMENT.name();
                Iterator<Vertex> adjacentVertices = catalogVertex.vertices(Direction.OUT, edgeLabel);
                return Either.left(adjacentVertices);
            } catch (Exception e) {
                logger.debug("Failed  get by  criteria: ", e);
                return Either.right(JanusGraphClient.handleJanusGraphException(e));
            }
        } else {
            logger.debug("Failed get by criteria : {}", graphEither.right().value());
            return Either.right(graphEither.right().value());
        }
    }

    private void buildMultipleNegateQueryFromList(Map.Entry<GraphPropertyEnum, Object> entry, JanusGraphQuery query) {
        for (Object listItem : (List<Object>) entry.getValue()) {
            query.hasNot(entry.getKey().getProperty(), listItem);
        }
    }

    /**
     * @param parentVertex
     * @param edgeLabel
     * @param parseFlag
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> getChildVertex(GraphVertex parentVertex, EdgeLabelEnum edgeLabel,
                                                                         JsonParseFlagEnum parseFlag) {
        Either<List<GraphVertex>, JanusGraphOperationStatus> childrenVertices = getChildrenVertices(parentVertex, edgeLabel, parseFlag);
        if (childrenVertices.isRight()) {
            return Either.right(childrenVertices.right().value());
        }
        return Either.left(childrenVertices.left().value().get(0));
    }

    /**
     * @param parentVertex
     * @param edgeLabel
     * @return
     */
    public Either<Vertex, JanusGraphOperationStatus> getChildVertex(Vertex parentVertex, EdgeLabelEnum edgeLabel) {
        Either<List<Vertex>, JanusGraphOperationStatus> childrenVertices = getChildrenVertices(parentVertex, edgeLabel);
        if (childrenVertices.isRight()) {
            return Either.right(childrenVertices.right().value());
        }
        return Either.left(childrenVertices.left().value().get(0));
    }

    public Either<GraphVertex, JanusGraphOperationStatus> getParentVertex(GraphVertex parentVertex, EdgeLabelEnum edgeLabel,
                                                                          JsonParseFlagEnum parseFlag) {
        Either<List<GraphVertex>, JanusGraphOperationStatus> childrenVertices = getParentVertices(parentVertex, edgeLabel, parseFlag);
        if (childrenVertices.isRight()) {
            return Either.right(childrenVertices.right().value());
        }
        if (isEmpty(childrenVertices.left().value())) {
            return Either.right(JanusGraphOperationStatus.NOT_FOUND);
        }
        return Either.left(childrenVertices.left().value().get(0));
    }

    public Either<Vertex, JanusGraphOperationStatus> getParentVertex(Vertex parentVertex, EdgeLabelEnum edgeLabel) {
        Either<List<Vertex>, JanusGraphOperationStatus> childrenVertices = getParentVertices(parentVertex, edgeLabel);
        if (childrenVertices.isRight()) {
            return Either.right(childrenVertices.right().value());
        }
        if (isEmpty(childrenVertices.left().value())) {
            return Either.right(JanusGraphOperationStatus.NOT_FOUND);
        }
        return Either.left(childrenVertices.left().value().get(0));
    }

    /**
     * @param parentVertex
     * @param edgeLabel
     * @param parseFlag
     * @return
     */
    public Either<List<GraphVertex>, JanusGraphOperationStatus> getChildrenVertices(GraphVertex parentVertex, EdgeLabelEnum edgeLabel,
                                                                                    JsonParseFlagEnum parseFlag) {
        return getAdjacentVertices(parentVertex, edgeLabel, parseFlag, Direction.OUT);
    }

    public Either<List<GraphVertex>, JanusGraphOperationStatus> getParentVertices(GraphVertex parentVertex, EdgeLabelEnum edgeLabel,
                                                                                  JsonParseFlagEnum parseFlag) {
        return getAdjacentVertices(parentVertex, edgeLabel, parseFlag, Direction.IN);
    }

    public Either<List<Vertex>, JanusGraphOperationStatus> getParentVertices(Vertex parentVertex, EdgeLabelEnum edgeLabel) {
        return getAdjacentVertices(parentVertex, edgeLabel, Direction.IN);
    }

    private Either<List<Vertex>, JanusGraphOperationStatus> getAdjacentVertices(Vertex parentVertex, EdgeLabelEnum edgeLabel, Direction direction) {
        List<Vertex> list = new ArrayList<>();
        try {
            Either<JanusGraph, JanusGraphOperationStatus> graphRes = janusGraphClient.getGraph();
            if (graphRes.isRight()) {
                logger.error("Failed to retrieve graph. status is {}", graphRes);
                return Either.right(graphRes.right().value());
            }
            Iterator<Edge> edgesCreatorIterator = parentVertex.edges(direction, edgeLabel.name());
            if (edgesCreatorIterator != null) {
                while (edgesCreatorIterator.hasNext()) {
                    Edge edge = edgesCreatorIterator.next();
                    JanusGraphVertex vertex;
                    if (direction == Direction.IN) {
                        vertex = (JanusGraphVertex) edge.outVertex();
                    } else {
                        vertex = (JanusGraphVertex) edge.inVertex();
                    }
                    list.add(vertex);
                }
            }
            if (list.isEmpty()) {
                return Either.right(JanusGraphOperationStatus.NOT_FOUND);
            }
        } catch (Exception e) {
            logger.error("Failed to perform graph operation ", e);
            Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return Either.left(list);
    }

    /**
     * @param parentVertex
     * @param edgeLabel
     * @return
     */
    public Either<List<Vertex>, JanusGraphOperationStatus> getChildrenVertices(Vertex parentVertex, EdgeLabelEnum edgeLabel) {
        return getAdjacentVertices(parentVertex, edgeLabel, Direction.OUT);
    }

    private Either<List<GraphVertex>, JanusGraphOperationStatus> getAdjacentVertices(GraphVertex parentVertex, EdgeLabelEnum edgeLabel,
                                                                                     JsonParseFlagEnum parseFlag, Direction direction) {
        List<GraphVertex> list = new ArrayList<>();
        Either<List<Vertex>, JanusGraphOperationStatus> adjacentVertices = getAdjacentVertices(parentVertex.getVertex(), edgeLabel,
            direction);
        if (adjacentVertices.isRight()) {
            return Either.right(adjacentVertices.right().value());
        }
        adjacentVertices.left().value().stream().forEach(vertex -> list.add(createAndFill((JanusGraphVertex) vertex, parseFlag)));
        return Either.left(list);
    }

    /**
     * Searches Edge by received label and criteria
     *
     * @param vertex
     * @param label
     * @param properties
     * @return found edge or JanusGraphOperationStatus
     */
    public Either<Edge, JanusGraphOperationStatus> getBelongingEdgeByCriteria(GraphVertex vertex, EdgeLabelEnum label,
                                                                              Map<GraphPropertyEnum, Object> properties) {
        Either<Edge, JanusGraphOperationStatus> result = null;
        Edge matchingEdge = null;
        String notFoundMsg = "No edges in graph for criteria";
        try {
            JanusGraphVertexQuery<?> query = vertex.getVertex().query().labels(label.name());
            if (properties != null && !properties.isEmpty()) {
                for (Map.Entry<GraphPropertyEnum, Object> entry : properties.entrySet()) {
                    query = query.has(entry.getKey().getProperty(), entry.getValue());
                }
            }
            Iterable<JanusGraphEdge> edges = query.edges();
            if (edges == null) {
                CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, notFoundMsg);
                result = Either.right(JanusGraphOperationStatus.NOT_FOUND);
            } else {
                Iterator<JanusGraphEdge> eIter = edges.iterator();
                if (eIter.hasNext()) {
                    matchingEdge = eIter.next();
                } else {
                    CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, notFoundMsg);
                    result = Either.right(JanusGraphOperationStatus.NOT_FOUND);
                }
            }
            if (result == null) {
                result = Either.left(matchingEdge);
            }
        } catch (Exception e) {
            CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, "Exception occured during getting edge by criteria for component with id {}. {}",
                vertex.getUniqueId(), e);
            return Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return result;
    }

    public Either<Edge, JanusGraphOperationStatus> getEdgeByChildrenVertexProperties(GraphVertex vertex, EdgeLabelEnum label,
                                                                                     Map<GraphPropertyEnum, Object> properties) {
        Either<Edge, JanusGraphOperationStatus> result = null;
        Edge matchingEdge = null;
        String notFoundMsg = "No edges in graph for criteria";
        try {
            Iterator<Edge> edges = vertex.getVertex().edges(Direction.OUT, label.name());
            while (edges.hasNext()) {
                matchingEdge = edges.next();
                Vertex childV = matchingEdge.inVertex();
                Map<GraphPropertyEnum, Object> vertexProperties = getVertexProperties(childV);
                Optional<Entry<GraphPropertyEnum, Object>> findNotMatch = properties.entrySet().stream()
                    .filter(e -> vertexProperties.get(e.getKey()) == null || !vertexProperties.get(e.getKey()).equals(e.getValue())).findFirst();
                if (!findNotMatch.isPresent()) {
                    result = Either.left(matchingEdge);
                }
            }
            if (result == null) {
                //no match 
                CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, notFoundMsg);
                result = Either.right(JanusGraphOperationStatus.NOT_FOUND);
            }
        } catch (Exception e) {
            CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, "Exception occured during getting edge by criteria for component with id {}. {}",
                vertex.getUniqueId(), e);
            return Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return result;
    }

    /**
     * Deletes Edge by received label and criteria
     *
     * @param vertex
     * @param label
     * @param properties
     * @return
     */
    public Either<Edge, JanusGraphOperationStatus> deleteBelongingEdgeByCriteria(GraphVertex vertex, EdgeLabelEnum label,
                                                                                 Map<GraphPropertyEnum, Object> properties) {
        Either<Edge, JanusGraphOperationStatus> result = null;
        try {
            result = getBelongingEdgeByCriteria(vertex, label, properties);
            if (result.isLeft()) {
                Edge edge = result.left().value();
                CommonUtility
                    .addRecordToLog(logger, LogLevelEnum.TRACE, "Going to delete an edge with the label {} belonging to the vertex {} ", label.name(),
                        vertex.getUniqueId());
                edge.remove();
                result = Either.left(edge);
            } else {
                CommonUtility
                    .addRecordToLog(logger, LogLevelEnum.DEBUG, "Failed to find an edge with the label {} belonging to the vertex {} ", label.name(),
                        vertex.getUniqueId());
            }
        } catch (Exception e) {
            CommonUtility
                .addRecordToLog(logger, LogLevelEnum.DEBUG, "Exception occured during deleting an edge by criteria for the component with id {}. {}",
                    vertex == null ? "NULL" : vertex.getUniqueId(), e);
            return Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return result;
    }

    @SuppressWarnings("unchecked")
    /**
     * Deletes an edge between vertices fromVertex and toVertex according to received label
     *
     * @param fromVertex
     * @param toVertex
     * @param label
     * @return
     */
    public Either<Edge, JanusGraphOperationStatus> deleteEdge(GraphVertex fromVertex, GraphVertex toVertex, EdgeLabelEnum label) {
        return deleteEdge(fromVertex.getVertex(), label, fromVertex.getUniqueId(), toVertex.getUniqueId(), false);
    }

    public Either<Edge, JanusGraphOperationStatus> deleteAllEdges(GraphVertex fromVertex, GraphVertex toVertex, EdgeLabelEnum label) {
        return deleteEdge(fromVertex.getVertex(), label, fromVertex.getUniqueId(), toVertex.getUniqueId(), true);
    }

    private Either<Edge, JanusGraphOperationStatus> deleteEdge(JanusGraphVertex fromVertex, EdgeLabelEnum label,
                                                               String uniqueIdFrom, String uniqueIdTo, boolean deleteAll) {
        Either<Edge, JanusGraphOperationStatus> result = null;
        Vertex problemV = null;
        try {
            Iterable<JanusGraphEdge> edges = fromVertex.query().labels(label.name()).edges();
            Iterator<JanusGraphEdge> eIter = edges.iterator();
            while (eIter.hasNext()) {
                Edge edge = eIter.next();
                problemV = edge.inVertex();
                String currVertexUniqueId = null;
                try {
                    currVertexUniqueId = edge.inVertex().value(GraphPropertyEnum.UNIQUE_ID.getProperty());
                } catch (Exception e) {
                    // AutoHealing procedure
                    logger.info("Corrupted vertex and edge were found and deleted ", e);
                    if (problemV != null) {
                        Map<GraphPropertyEnum, Object> props = getVertexProperties(problemV);
                        logger.debug("problematic Vertex properties:");
                        logger.debug("props size: {}", props.size());
                        for (Map.Entry<GraphPropertyEnum, Object> entry : props.entrySet()) {
                            logger.debug("{}:{}", entry.getKey(), entry.getValue());
                        }
                        Either<List<Vertex>, JanusGraphOperationStatus> childrenVertices = getChildrenVertices(problemV, EdgeLabelEnum.VERSION);
                        if (childrenVertices.isLeft()) {
                            childrenVertices.left().value().size();
                            logger.debug("number of children that problematic Vertex has: {}", props.size());
                        }
                        try {
                            edge.remove();
                        } catch (Exception e1) {
                            logger.debug("failed to remove problematic edge.", e1);
                        }
                        try {
                            problemV.remove();
                        } catch (Exception e2) {
                            logger.debug("failed to remove problematic vertex.", e2);
                        }
                    }
                    continue;
                }
                if (currVertexUniqueId != null && currVertexUniqueId.equals(uniqueIdTo)) {
                    CommonUtility.addRecordToLog(logger, LogLevelEnum.TRACE, "Going to delete an edge with the label {} between vertices {} and {}. ",
                        label.name(), uniqueIdFrom, uniqueIdTo);
                    edge.remove();
                    result = Either.left(edge);
                    if (!deleteAll) {
                        break;
                    }
                }
            }
            if (result == null) {
                CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, "Failed to delete an edge with the label {} between vertices {} and {}. ",
                    label.name(), uniqueIdFrom, uniqueIdTo);
                result = Either.right(JanusGraphOperationStatus.NOT_FOUND);
            }
        } catch (Exception e) {
            CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG,
                "Exception occured during deleting an edge with the label {} between vertices {} and {}. {}", label.name(), uniqueIdFrom, uniqueIdTo,
                e);
            return Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return result;
    }

    public JanusGraphOperationStatus deleteEdgeByDirection(GraphVertex fromVertex, Direction direction, EdgeLabelEnum label) {
        try {
            Iterator<Edge> edges = fromVertex.getVertex().edges(direction, label.name());
            while (edges.hasNext()) {
                Edge edge = edges.next();
                edge.remove();
            }
        } catch (Exception e) {
            logger.debug("Failed to remove from vertex {} edges {} by direction {} ", fromVertex.getUniqueId(), label, direction, e);
            return JanusGraphClient.handleJanusGraphException(e);
        }
        return JanusGraphOperationStatus.OK;
    }

    /**
     * Updates vertex properties. Note that graphVertex argument should contain updated data
     *
     * @param graphVertex
     * @return
     */
    public Either<GraphVertex, JanusGraphOperationStatus> updateVertex(GraphVertex graphVertex) {
        CommonUtility.addRecordToLog(logger, LogLevelEnum.TRACE, "Going to update metadata of vertex with uniqueId {}. ", graphVertex.getUniqueId());
        try {
            graphVertex.updateMetadataJsonWithCurrentMetadataProperties();
            setVertexProperties(graphVertex.getVertex(), graphVertex);
        } catch (Exception e) {
            CommonUtility
                .addRecordToLog(logger, LogLevelEnum.DEBUG, "Failed to update metadata of vertex with uniqueId {}. ", graphVertex.getUniqueId(), e);
            return Either.right(JanusGraphClient.handleJanusGraphException(e));
        }
        return Either.left(graphVertex);
    }

    /**
     * Fetches vertices by uniqueId according to received parse flag
     *
     * @param verticesToGet
     * @return
     */
    public Either<Map<String, GraphVertex>, JanusGraphOperationStatus> getVerticesByUniqueIdAndParseFlag(
        Map<String, ImmutablePair<GraphPropertyEnum, JsonParseFlagEnum>> verticesToGet) {
        Either<Map<String, GraphVertex>, JanusGraphOperationStatus> result = null;
        Map<String, GraphVertex> vertices = new HashMap<>();
        JanusGraphOperationStatus titatStatus;
        Either<GraphVertex, JanusGraphOperationStatus> getVertexRes = null;
        for (Map.Entry<String, ImmutablePair<GraphPropertyEnum, JsonParseFlagEnum>> entry : verticesToGet.entrySet()) {
            if (entry.getValue().getKey() == GraphPropertyEnum.UNIQUE_ID) {
                getVertexRes = getVertexById(entry.getKey(), entry.getValue().getValue());
            } else if (entry.getValue().getKey() == GraphPropertyEnum.USERID) {
                getVertexRes = getVertexByPropertyAndLabel(entry.getValue().getKey(), entry.getKey(), VertexTypeEnum.USER,
                    entry.getValue().getValue());
            }
            if (getVertexRes == null) {
                titatStatus = JanusGraphOperationStatus.ILLEGAL_ARGUMENT;
                CommonUtility
                    .addRecordToLog(logger, LogLevelEnum.DEBUG, "Invalid vertex type label {} has been received. ", entry.getValue().getKey(),
                        titatStatus);
                return Either.right(titatStatus);
            }
            if (getVertexRes.isRight()) {
                titatStatus = getVertexRes.right().value();
                CommonUtility
                    .addRecordToLog(logger, LogLevelEnum.DEBUG, "Failed to get vertex by id {} . Status is {}. ", entry.getKey(), titatStatus);
                result = Either.right(titatStatus);
                break;
            } else {
                vertices.put(entry.getKey(), getVertexRes.left().value());
            }
        }
        if (result == null) {
            result = Either.left(vertices);
        }
        return result;
    }

    /**
     * Creates edge between "from" and "to" vertices with specified label and properties extracted from received edge
     *
     * @param from
     * @param to
     * @param label
     * @param edgeToCopy
     * @return
     */
    public JanusGraphOperationStatus createEdge(Vertex from, Vertex to, EdgeLabelEnum label, Edge edgeToCopy) {
        return createEdge(from, to, label, getEdgeProperties(edgeToCopy));
    }

    public JanusGraphOperationStatus replaceEdgeLabel(Vertex fromVertex, Vertex toVertex, Edge prevEdge, EdgeLabelEnum prevLabel,
                                                      EdgeLabelEnum newLabel) {
        CommonUtility
            .addRecordToLog(logger, LogLevelEnum.TRACE, "Going to replace edge with label {} to {} between vertices {} and {}", prevLabel, newLabel,
                fromVertex != null ? fromVertex.property(GraphPropertyEnum.UNIQUE_ID.getProperty()) : "NULL",
                toVertex != null ? toVertex.property(GraphPropertyEnum.UNIQUE_ID.getProperty()) : "NULL");
        JanusGraphOperationStatus result = createEdge(fromVertex, toVertex, newLabel, prevEdge);
        if (result == JanusGraphOperationStatus.OK) {
            prevEdge.remove();
        }
        return result;
    }

    /**
     * Replaces previous label of edge with new label
     *
     * @param fromVertex
     * @param toVertex
     * @param prevLabel
     * @param newLabel
     * @return
     */
    public JanusGraphOperationStatus replaceEdgeLabel(Vertex fromVertex, Vertex toVertex, EdgeLabelEnum prevLabel, EdgeLabelEnum newLabel) {
        Iterator<Edge> prevEdgeIter = toVertex.edges(Direction.IN, prevLabel.name());
        if (prevEdgeIter == null || !prevEdgeIter.hasNext()) {
            CommonUtility
                .addRecordToLog(logger, LogLevelEnum.DEBUG, "Failed to replace edge with label {} to {} between vertices {} and {}", prevLabel,
                    newLabel, fromVertex.property(GraphPropertyEnum.UNIQUE_ID.getProperty()),
                    toVertex.property(GraphPropertyEnum.UNIQUE_ID.getProperty()));
            return JanusGraphOperationStatus.NOT_FOUND;
        } else {
            return replaceEdgeLabel(fromVertex, toVertex, prevEdgeIter.next(), prevLabel, newLabel);
        }
    }

    /**
     * Updates metadata properties of vertex on graph. Json metadata property of the vertex will be updated with received properties too.
     *
     * @param vertex
     * @param properties
     * @return
     */
    public JanusGraphOperationStatus updateVertexMetadataPropertiesWithJson(Vertex vertex, Map<GraphPropertyEnum, Object> properties) {
        try {
            if (!MapUtils.isEmpty(properties)) {
                String jsonMetadataStr = (String) vertex.property(GraphPropertyEnum.METADATA.getProperty()).value();
                Map<String, Object> jsonMetadataMap = JsonParserUtils.toMap(jsonMetadataStr);
                for (Map.Entry<GraphPropertyEnum, Object> property : properties.entrySet()) {
                    vertex.property(property.getKey().getProperty(), property.getValue());
                    jsonMetadataMap.put(property.getKey().getProperty(), property.getValue());
                }
                vertex.property(GraphPropertyEnum.METADATA.getProperty(), JsonParserUtils.toJson(jsonMetadataMap));
            }
        } catch (Exception e) {
            CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG, "Exception occurred during update vertex metadata properties with json{}. {}",
                vertex.property(GraphPropertyEnum.UNIQUE_ID.getProperty()), e.getMessage());
            return JanusGraphClient.handleJanusGraphException(e);
        }
        return JanusGraphOperationStatus.OK;
    }

    public JanusGraphOperationStatus disassociateAndDeleteLast(GraphVertex vertex, Direction direction, EdgeLabelEnum label) {
        try {
            Iterator<Edge> edges = vertex.getVertex().edges(direction, label.name());
            while (edges.hasNext()) {
                Edge edge = edges.next();
                Vertex secondVertex;
                Direction reverseDirection;
                if (direction == Direction.IN) {
                    secondVertex = edge.outVertex();
                    reverseDirection = Direction.OUT;
                } else {
                    secondVertex = edge.inVertex();
                    reverseDirection = Direction.IN;
                }
                edge.remove();
                CommonUtility.addRecordToLog(logger, LogLevelEnum.TRACE, "Edge  {} with direction {} was removed from {}", label.name(), direction,
                    vertex.getVertex());
                Iterator<Edge> restOfEdges = secondVertex.edges(reverseDirection, label.name());
                if (!restOfEdges.hasNext()) {
                    secondVertex.remove();
                    CommonUtility.addRecordToLog(logger, LogLevelEnum.TRACE, "This was last edge . Vertex  {} was removed ", vertex.getUniqueId());
                }
            }
        } catch (Exception e) {
            CommonUtility.addRecordToLog(logger, LogLevelEnum.DEBUG,
                "Exception occured during deleting an edge with the label {} direction {} from vertex {}. {}", label.name(), direction,
                vertex.getUniqueId(), e);
            return JanusGraphClient.handleJanusGraphException(e);
        }
        return JanusGraphOperationStatus.OK;
    }

    public Object getProperty(JanusGraphVertex vertex, String key) {
        PropertyKey propertyKey = janusGraphClient.getGraph().left().value().getPropertyKey(key);
        return vertex.valueOrNull(propertyKey);
    }

    public Object getProperty(Edge edge, EdgePropertyEnum key) {
        Object value = null;
        try {
            Property<Object> property = edge.property(key.getProperty());
            if (property != null) {
                value = property.orElse(null);
                if (value != null && key == EdgePropertyEnum.INSTANCES) {
                    return JsonParserUtils.toList((String) value, String.class);
                }
                return value;
            }
        } catch (Exception e) {
        }
        return value;
    }

    /**
     * @param vertexA
     * @param vertexB
     * @param label
     * @param direction
     * @return
     */
    public JanusGraphOperationStatus moveEdge(GraphVertex vertexA, GraphVertex vertexB, EdgeLabelEnum label, Direction direction) {
        JanusGraphOperationStatus result = deleteEdgeByDirection(vertexA, direction, label);
        if (result != JanusGraphOperationStatus.OK) {
            logger.error("Failed to disassociate {} from element {}. error {} ", label, vertexA.getUniqueId(), result);
            return result;
        }
        JanusGraphOperationStatus createRelation;
        if (direction == Direction.IN) {
            createRelation = createEdge(vertexB, vertexA, label, null);
        } else {
            createRelation = createEdge(vertexA, vertexB, label, null);
        }
        if (createRelation != JanusGraphOperationStatus.OK) {
            return createRelation;
        }
        return JanusGraphOperationStatus.OK;
    }

    public Either<Edge, JanusGraphOperationStatus> getBelongingEdgeByCriteria(String parentId, EdgeLabelEnum label,
                                                                              Map<GraphPropertyEnum, Object> properties) {
        Either<GraphVertex, JanusGraphOperationStatus> getVertexRes = getVertexById(parentId, JsonParseFlagEnum.NoParse);
        if (getVertexRes.isRight()) {
            return Either.right(getVertexRes.right().value());
        }
        return getBelongingEdgeByCriteria(getVertexRes.left().value(), label, properties);
    }

    private JanusGraphQuery<? extends JanusGraphQuery> getJanusGraphQuery(final VertexTypeEnum type, final Map<GraphPropertyEnum, Object> hasProps,
                                                                          final Map<GraphPropertyEnum, Object> hasNotProps,
                                                                          final Map<String, Entry<JanusGraphPredicate, Object>> predicates,
                                                                          final JanusGraph graph) {
        JanusGraphQuery<? extends JanusGraphQuery> query = graph.query();

        if (type != null) {
            query = query.has(GraphPropertyEnum.LABEL.getProperty(), type.getName());
        }
        if (hasProps != null && !hasProps.isEmpty()) {
            for (Entry<GraphPropertyEnum, Object> entry : hasProps.entrySet()) {
                query = query.has(entry.getKey().getProperty(), entry.getValue());
            }
        }
        if (hasNotProps != null && !hasNotProps.isEmpty()) {
            for (Entry<GraphPropertyEnum, Object> entry : hasNotProps.entrySet()) {
                if (entry.getValue() instanceof List) {
                    buildMultipleNegateQueryFromList(entry, query);
                } else {
                    query = query.hasNot(entry.getKey().getProperty(), entry.getValue());
                }
            }
        }
        if (predicates != null && !predicates.isEmpty()) {
            for (Entry<String, Entry<JanusGraphPredicate, Object>> entry : predicates.entrySet()) {
                query = query.has(entry.getKey(), entry.getValue().getKey(), entry.getValue().getValue());
            }
        }
        return query;
    }
}