/**
 * ============LICENSE_START=======================================================
 * org.onap.aai
 * ================================================================================
 * Copyright © 2017-2018 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.onap.aai.rest.search;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import edu.emory.mathcs.backport.java.util.concurrent.TimeUnit;

import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal;
import org.apache.tinkerpop.gremlin.structure.Vertex;
import org.javatuples.Pair;
import org.onap.aai.exceptions.AAIException;
import org.onap.aai.restcore.search.GroovyQueryBuilder;
import org.onap.aai.serialization.engines.TransactionalGraphEngine;
import org.onap.aai.serialization.queryformats.SubGraphStyle;

import java.io.FileNotFoundException;
import java.util.*;
import java.util.regex.Pattern;

import javax.ws.rs.core.MultivaluedHashMap;
import javax.ws.rs.core.MultivaluedMap;

public class NodeQueryProcessor extends GroovyShellImpl {

	private static Logger logger = LoggerFactory.getLogger(NodeQueryProcessor.class);

	protected String nodeType;
	private MultivaluedMap<String, String> nodeQueryParams = new MultivaluedHashMap<>();
	protected final Optional<Collection<Vertex>> vertices;
	protected static Pattern p = Pattern.compile("query/(.*+)");
	protected Optional<String> gremlin;
	protected final TransactionalGraphEngine dbEngine;
	protected GroovyQueryBuilder queryBuilder = new GroovyQueryBuilder();

	protected NodeQueryProcessor(Builder builder) {
		super(builder);
		this.nodeQueryParams = builder.uriParams;
		if(builder.getNodeType().isPresent()) {
			this.nodeType = builder.getNodeType().get();
		}
		this.dbEngine = builder.getDbEngine();
		this.vertices = builder.getVertices();

	}

	public Pair<String, Map<String, Object>> createQuery() throws AAIException {
		Map<String, Object> params = new HashMap<>();

		Long timeNowInMilliSecs = System.currentTimeMillis();
		Long startTime = 0L;
		if(nodeQueryParams.containsKey("hours")){
			Long hoursInMilliSec = TimeUnit.HOURS.toMillis(Long.parseLong(nodeQueryParams.getFirst("hours")));
			startTime = timeNowInMilliSecs - hoursInMilliSec;
		}
		else if(nodeQueryParams.containsKey("date-time")){
			Long dateTime = Long.parseLong(nodeQueryParams.getFirst("date-time"));
			startTime = dateTime;
		}	
		
		String query = "builder.getVerticesByProperty('aai-node-type', nodeType)"
				+ ".or(builder.newInstance().getVerticesGreaterThanProperty('aai-created-ts',startTime),"
				+ "  builder.newInstance().getVerticesGreaterThanProperty('aai-last-mod-ts',startTime)" + ")";

		params.put("startTime", startTime);
		params.put("nodeType", nodeType);
		
		query = queryBuilder.executeTraversal(dbEngine, query, params);

		String startPrefix = "g.V()";

		query = startPrefix + query;

		if (logger.isDebugEnabled()) {
			logger.debug("Converted to gremlin query without the start vertices \n {}", query);
		}

		return new Pair<>(query, params);
	}

	public List<Object> execute(SubGraphStyle style) throws FileNotFoundException, AAIException {
		final List<Object> resultVertices = new Vector<>();

		Pair<String, Map<String, Object>> tuple = this.createQuery();
		String query = tuple.getValue0();
		Map<String, Object> params = tuple.getValue1();

		if (query.equals("")) {
			// nothing to do, just exit
			return new ArrayList<>();
		}
		GraphTraversal<?, ?> g = this.runQuery(query, params, dbEngine.asAdmin().getTraversalSource());

		resultVertices.addAll(g.toList());

		return resultVertices;
	}

}