D-Net

package eu.dnetlib.data.transform;

import java.util.Collection;

import java.util.List;

import java.util.Map;

import java.util.Set;

import java.util.stream.Collectors;

import java.util.stream.Stream;

import com.google.common.base.Functions;

import com.google.common.base.Predicate;

import com.google.common.collect.Iterables;

import com.google.common.collect.Lists;

import com.google.common.collect.Maps;

import com.google.common.collect.Sets;

import com.google.protobuf.Descriptors.FieldDescriptor;

import com.google.protobuf.Message.Builder;

import eu.dnetlib.data.proto.FieldTypeProtos;

import eu.dnetlib.data.proto.FieldTypeProtos.KeyValue;

import eu.dnetlib.data.proto.FieldTypeProtos.Qualifier;

import eu.dnetlib.data.proto.FieldTypeProtos.StringField;

import eu.dnetlib.data.proto.FieldTypeProtos.StructuredProperty;

import eu.dnetlib.data.proto.KindProtos.Kind;

import eu.dnetlib.data.proto.OafProtos.Oaf;

import eu.dnetlib.data.proto.OafProtos.OafEntity;

import eu.dnetlib.data.proto.ResultProtos;

import eu.dnetlib.data.proto.ResultProtos.Result;

import eu.dnetlib.data.proto.ResultProtos.Result.Instance;

import eu.dnetlib.data.proto.SpecialTrustProtos.SpecialTrust;

import eu.dnetlib.data.proto.TypeProtos.Type;

import eu.dnetlib.pace.config.DedupConfig;

import org.apache.commons.lang.StringUtils;

public class OafEntityMerger {

	private static final String DEDUP_CLASSID = "sysimport:dedup";

	private static final String DNET_PROVENANCE_SCHEME = "dnet:provenanceActions";

	private final Predicate<StringField> skipEmptyStringField = s -> (s != null) && (s.getValue() != null) && !s.getValue().isEmpty();

	private final Predicate<String> skipEmptyString = s -> StringUtils.isNotBlank(s);

	public static Oaf.Builder merge(final String id, final Iterable<Oaf> entities) {

		return merge(null, id, entities);

	}

	public static Oaf.Builder merge(final DedupConfig dedupConf, final String id, final Iterable<Oaf> entities) {

		return new OafEntityMerger().mergeEntities(dedupConf, id, entities);

	}

	public static Oaf.Builder merge(final Oaf.Builder builder) {

		return new OafEntityMerger().doMergeEntities(builder);

	}

	public Oaf.Builder mergeEntities(final DedupConfig dedupConf, final String id, final Iterable<Oaf> entities) {

		Oaf.Builder builder = Oaf.newBuilder();

		String trust = "0.0";

		for (final Oaf oaf : TrustOrdering.sort(entities)) {

			// doublecheck we're dealing only with main entities

			if (!oaf.getKind().equals(Kind.entity)) throw new IllegalArgumentException("expected OafEntity!");

			final String currentTrust = oaf.getDataInfo().getTrust();

			if (!currentTrust.equals(SpecialTrust.NEUTRAL.toString())) {

				trust = currentTrust;

			}

			builder.mergeFrom(oaf);

			if (oaf.getEntity().getType().equals(Type.result)) {

				builder.getEntityBuilder().getResultBuilder().getMetadataBuilder().clearAuthor();

				builder.getEntityBuilder().getResultBuilder().getMetadataBuilder().addAllAuthor(oaf.getEntity().getResult().getMetadata().getAuthorList());

			}

		}

		builder = doMergeEntities(builder);

		builder.getEntityBuilder().setId(id);

		builder.getDataInfoBuilder()

				.setInvisible(false)

				.setInferred(true)

				.setDeletedbyinference(false)

				.setTrust(trust)

				.setInferenceprovenance(dedupConf != null ? dedupConf.getWf().getConfigurationId() : "")

				.setProvenanceaction(getProvenanceAction());

		if ((dedupConf != null) && dedupConf.getWf().isIncludeChildren()) {

			for (final Oaf oaf : Iterables.limit(entities, dedupConf.getWf().getMaxChildren())) {

				builder.getEntityBuilder().addChildren(oaf.getEntity());

			}

		}

		return builder;

	}

	private Qualifier.Builder getProvenanceAction() {

		return Qualifier.newBuilder().setClassid(DEDUP_CLASSID).setClassname(DEDUP_CLASSID).setSchemeid(DNET_PROVENANCE_SCHEME)

				.setSchemename(DNET_PROVENANCE_SCHEME);

	}

	public Oaf.Builder doMergeEntities(final Oaf.Builder builder) {

		for (final String field : OafUtils.getFieldNames(OafEntity.getDescriptor(), OafEntity.COLLECTEDFROM_FIELD_NUMBER)) {

			setKeyValues(builder.getEntityBuilder(), field);

		}

		for (final String field : OafUtils.getFieldNames(OafEntity.getDescriptor(), OafEntity.PID_FIELD_NUMBER)) {

			setStructuredProperty(builder.getEntityBuilder(), field);

		}

		for (final String field : OafUtils.getFieldNames(OafEntity.getDescriptor(), OafEntity.ORIGINALID_FIELD_NUMBER)) {

			setUniqueString(builder.getEntityBuilder(), field);

		}

		switch (builder.getEntity().getType()) {

		case datasource:

			break;

		case organization:

			break;

		case project:

			break;

		case result:

			final Result.Metadata.Builder result = builder.getEntityBuilder().getResultBuilder().getMetadataBuilder();

			setTitle(result);

			mergeInstances(builder.getEntityBuilder().getResultBuilder());

			// for (String field : Lists.newArrayList("subject", "relevantdate")) {

			for (final String field : OafUtils.getFieldNames(Result.Metadata.getDescriptor(), Result.Metadata.SUBJECT_FIELD_NUMBER,

					Result.Metadata.RELEVANTDATE_FIELD_NUMBER)) {

				setStructuredProperty(result, field);

			}

			for (final String field : OafUtils.getFieldNames(Result.Metadata.getDescriptor(), Result.Metadata.DESCRIPTION_FIELD_NUMBER)) {

				setLongestStringField(result, field);

			}

			for (final String field : OafUtils.getFieldNames(Result.Metadata.getDescriptor(), Result.Metadata.SOURCE_FIELD_NUMBER)) {

				setUniqueStringField(result, field);

			}

			mergeContexts(result);

			mergeCountries(result);

			break;

		default:

			break;

		}

		return builder;

	}

	private void mergeCountries(Result.Metadata.Builder result) {

		final Map<String, Qualifier.Builder> cMap = Maps.newHashMap();

		for(Qualifier country : result.getCountryList()) {

			if (!cMap.containsKey(country.getClassid())) {

				cMap.put(country.getClassid(), Qualifier.newBuilder(country));

			}

		}

		if (!cMap.isEmpty()) {

			result.clearCountry();

			for(Qualifier.Builder country : cMap.values()) {

				result.addCountry(country.build());

			}

		}

	}

	private void mergeContexts(Result.Metadata.Builder result) {

		final Map<String, Result.Context.Builder> cMap = Maps.newHashMap();

		for(Result.Context c : result.getContextList()) {

			if (!cMap.containsKey(c.getId())) {

				//TODO merge DataInfo

				cMap.put(c.getId(), Result.Context.newBuilder(c));

			}

		}

		if (!cMap.isEmpty()) {

			result.clearContext();

			for (Result.Context.Builder b : cMap.values()) {

				result.addContext(b.build());

			}

		}

	}

	private void mergeInstances(final Result.Builder builder) {

		final Map<String, Instance.Builder> map = Maps.newHashMap();

		for(Instance i : builder.getInstanceList()) {

			final String key = i.getHostedby().getKey() + i.getAccessright().getClassid() + i.getInstancetype().getClassid();

			if (!map.containsKey(key)) {

				map.put(key, Instance.newBuilder().mergeFrom(i));

				continue;

			}

			map.get(key).addAllUrl(i.getUrlList());

		}

		for(Instance.Builder i : map.values()) {

			final Set<String> urls = Sets.newHashSet();

			urls.addAll(i.getUrlList());

			i.clearUrl().addAllUrl(urls);

		}

		builder.clearInstance();

		builder.addAllInstance(Iterables.transform(map.values(), b -> b.build()));

	}

	/**

	 * Helper method, avoid duplicated StructuredProperties in the given builder for the given fieldName

	 *

	 * @param builder

	 * @param fieldName

	 */

	@SuppressWarnings("unchecked")

	private void setStructuredProperty(final Builder builder, final String fieldName) {

		final Map<String, StructuredProperty> map = Maps.newHashMap();

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<StructuredProperty> sps = (List<StructuredProperty>) builder.getField(fd);

		if ((sps != null) && !sps.isEmpty()) {

			for (final StructuredProperty sp : sps) {

				if (StringUtils.isNotBlank(sp.getValue())) {

					map.put(sp.getValue().toLowerCase(), sp);

				}

			}

			if (!map.isEmpty()) {

				builder.clearField(fd).setField(fd, Lists.newArrayList(map.values()));

			}

		}

	}

	/**

	 * Helper method, avoid duplicated KeyValues in the given builder for the given fieldName

	 *

	 * @param builder

	 * @param fieldName

	 */

	@SuppressWarnings("unchecked")

	private void setKeyValues(final Builder builder, final String fieldName) {

		final Map<String, KeyValue> map = Maps.newHashMap();

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<KeyValue> kvs = (List<KeyValue>) builder.getField(fd);

		if ((kvs != null) && !kvs.isEmpty()) {

			for (final KeyValue sp : kvs) {

				map.put(sp.getKey(), sp);

			}

			if (!map.isEmpty()) {

				builder.clearField(fd).setField(fd, Lists.newArrayList(map.values()));

			}

		}

	}

	@SuppressWarnings("unchecked")

	private void setSingleString(final Builder builder, final String fieldName) {

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<StringField> field = (List<StringField>) builder.getField(fd);

		if ((field != null) && !field.isEmpty()) {

			final StringField s = (StringField) Iterables.getLast(Iterables.filter(field, skipEmptyStringField), "");

			if ((s != null) && (s.getValue() != null) && !s.getValue().isEmpty()) {

				builder.clearField(fd).setField(fd, Lists.newArrayList(s));

			}

		}

	}

	@SuppressWarnings("unchecked")

	private void setLongestStringField(final Builder builder, final String fieldName) {

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<StringField> field = (List<StringField>) builder.getField(fd);

		if ((field != null) && !field.isEmpty()) {

			final StringField.Builder max = StringField.newBuilder().setValue("");

			int maxLength = 0;

			for (final StringField sf : field) {

				if (sf.getValue().length() > maxLength) {

					maxLength = sf.getValue().length();

					max.clear();

					max.mergeFrom(sf);

				}

			}

			builder.clearField(fd).setField(fd, Lists.newArrayList(max.build()));

		}

	}

	@SuppressWarnings("unchecked")

	private void setUniqueStringField(final Builder builder, final String fieldName) {

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<StringField> field = (List<StringField>) builder.getField(fd);

		final Map<String, StringField> map = Maps.newHashMap();

		if ((field != null) && !field.isEmpty()) {

			for (final StringField s : Iterables.filter(field, skipEmptyStringField)) {

				map.put(s.getValue(), s);

			}

			builder.clearField(fd).setField(fd, Lists.newArrayList(map.values()));

		}

	}

	@SuppressWarnings("unchecked")

	private void setUniqueString(final Builder builder, final String fieldName) {

		final FieldDescriptor fd = builder.getDescriptorForType().findFieldByName(fieldName);

		final List<String> field = (List<String>) builder.getField(fd);

		final Set<String> set = Sets.newHashSet();

		if ((field != null) && !field.isEmpty()) {

			for (final String s : Iterables.filter(field, skipEmptyString)) {

				set.add(s);

			}

			builder.clearField(fd).setField(fd, Lists.newArrayList(set));

		}

	}

	private void setTitle(final Result.Metadata.Builder metadata) {

		final Iterable<StructuredProperty> filtered = Iterables.filter(metadata.getTitleList(), OafUtils.mainTitleFilter());

		if (!Iterables.isEmpty(filtered)) {

			metadata.clearTitle().addTitle(Iterables.getLast(filtered));

		}

	}

}