package eu.dnetlib.dhp.actionmanager.createunresolvedentities;

import static eu.dnetlib.dhp.actionmanager.Constants.*;
import static eu.dnetlib.dhp.common.SparkSessionSupport.runWithSparkSession;

import java.io.Serializable;
import java.util.*;
import java.util.stream.Collectors;

import org.apache.commons.io.IOUtils;
import org.apache.spark.SparkConf;
import org.apache.spark.api.java.function.MapFunction;
import org.apache.spark.api.java.function.MapGroupsFunction;
import org.apache.spark.sql.Dataset;
import org.apache.spark.sql.Encoders;
import org.apache.spark.sql.SaveMode;
import org.apache.spark.sql.SparkSession;
import org.jetbrains.annotations.NotNull;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import eu.dnetlib.dhp.actionmanager.createunresolvedentities.model.FOSDataModel;
import eu.dnetlib.dhp.application.ArgumentApplicationParser;
import eu.dnetlib.dhp.schema.common.ModelConstants;
import eu.dnetlib.dhp.schema.common.ModelSupport;
import eu.dnetlib.dhp.schema.oaf.Result;
import eu.dnetlib.dhp.schema.oaf.StructuredProperty;
import eu.dnetlib.dhp.schema.oaf.Subject;
import eu.dnetlib.dhp.schema.oaf.utils.OafMapperUtils;
import eu.dnetlib.dhp.utils.DHPUtils;

public class PrepareFOSSparkJob implements Serializable {
	private static final Logger log = LoggerFactory.getLogger(PrepareFOSSparkJob.class);

	public static void main(String[] args) throws Exception {

		String jsonConfiguration = IOUtils
			.toString(
				PrepareFOSSparkJob.class
					.getResourceAsStream(
						"/eu/dnetlib/dhp/actionmanager/createunresolvedentities/prepare_parameters.json"));

		final ArgumentApplicationParser parser = new ArgumentApplicationParser(jsonConfiguration);

		parser.parseArgument(args);

		Boolean isSparkSessionManaged = isSparkSessionManaged(parser);
		log.info("isSparkSessionManaged: {}", isSparkSessionManaged);

		String sourcePath = parser.get("sourcePath");
		log.info("sourcePath: {}", sourcePath);

		final String outputPath = parser.get("outputPath");
		log.info("outputPath: {}", outputPath);

		final Boolean distributeDOI = Optional
			.ofNullable(parser.get("distributeDoi"))
			.map(Boolean::valueOf)
			.orElse(Boolean.TRUE);

		SparkConf conf = new SparkConf();
		runWithSparkSession(
			conf,
			isSparkSessionManaged,
			spark -> {
				if (distributeDOI)
					distributeFOSdois(
						spark,
						sourcePath,

						outputPath);
				else
					distributeFOSoaid(spark, sourcePath, outputPath);
			});
	}

	private static void distributeFOSoaid(SparkSession spark, String sourcePath, String outputPath) {
		Dataset<FOSDataModel> fosDataset = readPath(spark, sourcePath, FOSDataModel.class);

		fosDataset
			.groupByKey((MapFunction<FOSDataModel, String>) v -> v.getOaid().toLowerCase(), Encoders.STRING())
			.mapGroups((MapGroupsFunction<String, FOSDataModel, Result>) (k, it) -> {
				return getResult(ModelSupport.getIdPrefix(Result.class) + "|" + k, it);
			}, Encoders.bean(Result.class))
			.write()
			.mode(SaveMode.Overwrite)
			.option("compression", "gzip")
			.json(outputPath + "/fos");
	}

	@NotNull
	private static Result getResult(String k, Iterator<FOSDataModel> it) {
		Result r = new Result();
		FOSDataModel first = it.next();
		r.setId(k);

		HashSet<String> level1 = new HashSet<>();
		HashSet<String> level2 = new HashSet<>();
		HashSet<String> level3 = new HashSet<>();
		HashSet<String> level4 = new HashSet<>();
		addLevels(level1, level2, level3, level4, first);
		it.forEachRemaining(v -> addLevels(level1, level2, level3, level4, v));
		List<Subject> sbjs = new ArrayList<>();
		level1
			.forEach(l -> add(sbjs, getSubject(l, FOS_CLASS_ID, FOS_CLASS_NAME, UPDATE_SUBJECT_FOS_CLASS_ID)));
		level2
			.forEach(l -> add(sbjs, getSubject(l, FOS_CLASS_ID, FOS_CLASS_NAME, UPDATE_SUBJECT_FOS_CLASS_ID)));
		level3
			.forEach(
				l -> add(sbjs, getSubject(l, FOS_CLASS_ID, FOS_CLASS_NAME, UPDATE_SUBJECT_FOS_CLASS_ID, true)));
		level4
			.forEach(
				l -> add(sbjs, getSubject(l, FOS_CLASS_ID, FOS_CLASS_NAME, UPDATE_SUBJECT_FOS_CLASS_ID, true)));
		r.setSubject(sbjs);
		r
			.setDataInfo(
				OafMapperUtils
					.dataInfo(
						false, null, true,
						false,
						OafMapperUtils
							.qualifier(
								ModelConstants.PROVENANCE_ENRICH,
								null,
								ModelConstants.DNET_PROVENANCE_ACTIONS,
								ModelConstants.DNET_PROVENANCE_ACTIONS),
						null));
		return r;
	}

	private static void distributeFOSdois(SparkSession spark, String sourcePath, String outputPath) {
		Dataset<FOSDataModel> fosDataset = readPath(spark, sourcePath, FOSDataModel.class);

		fosDataset
			.groupByKey((MapFunction<FOSDataModel, String>) v -> v.getDoi().toLowerCase(), Encoders.STRING())
			.mapGroups(
				(MapGroupsFunction<String, FOSDataModel, Result>) (k,
					it) -> getResult(DHPUtils.generateUnresolvedIdentifier(k, DOI), it),
				Encoders.bean(Result.class))
			.write()
			.mode(SaveMode.Overwrite)
			.option("compression", "gzip")
			.json(outputPath + "/fos");
	}

	private static void add(List<Subject> sbsjs, Subject sbj) {
		if (sbj != null)
			sbsjs.add(sbj);
	}

	private static void addLevels(HashSet<String> level1, HashSet<String> level2, HashSet<String> level3,
		HashSet<String> level4,
		FOSDataModel first) {
		level1.add(first.getLevel1());
		level2.add(first.getLevel2());
		if (Optional.ofNullable(first.getLevel3()).isPresent() &&
			!first.getLevel3().equalsIgnoreCase(NA) && !first.getLevel3().equalsIgnoreCase(NULL)
			&& first.getLevel3() != null)
			level3.add(first.getLevel3() + "@@" + first.getScoreL3());
		else
			level3.add(NULL);
		if (Optional.ofNullable(first.getLevel4()).isPresent() &&
			!first.getLevel4().equalsIgnoreCase(NA) &&
			!first.getLevel4().equalsIgnoreCase(NULL) &&
			first.getLevel4() != null)
			level4.add(first.getLevel4() + "@@" + first.getScoreL4());
		else
			level4.add(NULL);
	}

}