/**
 * ============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.dbmap;

import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;

import java.util.Properties;

import org.apache.tinkerpop.gremlin.structure.io.IoCore;
import org.onap.aai.dbgen.SchemaGenerator;
import org.onap.aai.logging.LogFormatTools;

import org.janusgraph.core.JanusGraphFactory;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphTransaction;
import org.janusgraph.core.schema.JanusGraphManagement;

import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;

public class InMemoryGraph {

	private static final EELFLogger LOGGER = EELFManager.getInstance().getLogger(InMemoryGraph.class);
	private JanusGraph graph = null;


	public InMemoryGraph(Builder builder) throws IOException  {
		/*
		 * Create a In-memory graph
		 */
		InputStream is = new FileInputStream(builder.propertyFile);
		try {
			graph = JanusGraphFactory.open(builder.propertyFile);
			
			Properties graphProps = new Properties();
			graphProps.load(is);
			JanusGraphManagement graphMgt = graph.openManagement();
            if(builder.isSchemaEnabled){
            	LOGGER.info("Schema Enabled");
            	SchemaGenerator.loadSchemaIntoJanusGraph(graphMgt);
            }
			JanusGraphTransaction transaction = graph.newTransaction();
			LOGGER.info("Loading snapshot");
			transaction.io(IoCore.graphson()).readGraph(builder.graphsonLocation);
			transaction.commit();
			
		} catch (Exception e) {
			// TODO : Changesysout to logger
			LOGGER.error(
					"ERROR: Could not load datasnapshot to in memory graph. \n" + LogFormatTools.getStackTop(e));
			throw new IllegalStateException("Could not load datasnapshot to in memory graph");

		}
		finally{
			is.close();
		}

	}

	public static class Builder {
		private String graphsonLocation = "";
		private String propertyFile = "";
		private boolean isSchemaEnabled = false;

		/*
		 * Builder constructor doesnt do anything
		 */
		public Builder() {
			//Do nothing
		}

		public InMemoryGraph build(String graphsonFile, String propertyFile, boolean isSchemaEnabled) throws IOException {
			this.graphsonLocation = graphsonFile;
			this.propertyFile = propertyFile;
			this.isSchemaEnabled = isSchemaEnabled;
			return new InMemoryGraph(this);
		}
	}

	public JanusGraph getGraph() {
		return graph;
	}

}