//Dstl (c) Crown Copyright 2017
/*
 *
 */
package uk.gov.dstl.baleen.jobs.interactions.io;

import java.util.Collection;

import org.bson.Document;

import com.mongodb.Mongo;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;

import uk.gov.dstl.baleen.jobs.interactions.UploadInteractionsToMongo;
import uk.gov.dstl.baleen.jobs.interactions.data.InteractionDefinition;


/**
 * Write interaction data to Mongo database.
 * <p>
 * This will output interaction data into two different collection for different uses by other
 * annotators.
 * <p>
 * It first outputs interaction words into Mongo gazetteer format (see {@link Mongo} for more
 * details). This allows the standard Baleen Mongo gazetteer annotators to mark up Interaction
 * words.
 * <p>
 * Secondly it saves information about relationship type constraints to the relationTypeCollection.
 * This is used by the {@link RelationTypeFilter} in order to remove any invalid relationships
 * between types. The relation (DateTime, said, Location) is likely to be invalid for example. Valid
 * options is derived directly from the
 * <p>
 * See {@link UploadInteractionsToMongo} for more details.
 *
 */
public class MongoInteractionWriter implements InteractionWriter {

	/** The relation types. */
	private final MongoCollection<Document> relationTypes;

	/** The interactions. */
	private final MongoCollection<Document> interactions;

	/**
	 * Instantiates a new instance.
	 *
	 * @param db
	 *            the db the write to
	 * @param relationTypesCollection
	 *            the relation types collection name
	 * @param interactionCollection
	 *            the interaction collection name
	 */
	public MongoInteractionWriter(MongoDatabase db, String relationTypesCollection, String interactionCollection) {
		interactions = db.getCollection(interactionCollection);
		relationTypes = db.getCollection(relationTypesCollection);
	}

	@Override
	public void write(InteractionDefinition interaction,
			Collection<String> alternatives) {

		// Write to the interactions collection
		// Add in relationshiptype and subtype (which can be manually changed later)
		final Document interactionObject = new Document()
			.append("relationshipType", interaction.getType())
			.append("relationSubType", interaction.getSubType())
			.append("value", alternatives);
		
		interactions.insertOne(interactionObject);

		// Write out to the relationship constraints
		final Document relationTypeObject = new Document()
			.append("source", interaction.getSource())
			.append("target", interaction.getTarget())
			.append("type", interaction.getType())
			.append("subType", interaction.getSubType())
			.append("pos", interaction.getWord().getPos().getLabel())
			.append("value", alternatives);

		relationTypes.insertOne(relationTypeObject);
	}

	/**
	 * Clear all collections.
	 */
	public void clear() {
		interactions.deleteMany(new Document());
		relationTypes.deleteMany(new Document());
	}
}