package com.linkedin.datahub.graphql.resolvers.query;

import com.datahub.authentication.Authentication;
import com.linkedin.common.urn.Urn;
import com.linkedin.common.urn.UrnUtils;
import com.linkedin.datahub.graphql.QueryContext;
import com.linkedin.datahub.graphql.authorization.AuthorizationUtils;
import com.linkedin.datahub.graphql.exception.AuthorizationException;
import com.linkedin.metadata.service.QueryService;
import com.linkedin.query.QuerySubject;
import com.linkedin.query.QuerySubjects;
import graphql.schema.DataFetcher;
import graphql.schema.DataFetchingEnvironment;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.CompletableFuture;
import java.util.stream.Collectors;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;


@Slf4j
@RequiredArgsConstructor
public class DeleteQueryResolver implements DataFetcher<CompletableFuture<Boolean>> {

  private final QueryService _queryService;

  @Override
  public CompletableFuture<Boolean> get(final DataFetchingEnvironment environment) throws Exception {
    final QueryContext context = environment.getContext();
    final Urn queryUrn = UrnUtils.getUrn(environment.getArgument("urn"));
    final Authentication authentication = context.getAuthentication();

    return CompletableFuture.supplyAsync(() -> {

      final QuerySubjects existingSubjects = _queryService.getQuerySubjects(queryUrn, authentication);
      final List<Urn> subjectUrns = existingSubjects != null
          ? existingSubjects.getSubjects().stream().map(QuerySubject::getEntity).collect(Collectors.toList())
          : Collections.emptyList();

      if (!AuthorizationUtils.canDeleteQuery(queryUrn, subjectUrns, context)) {
        throw new AuthorizationException(
            "Unauthorized to delete Query. Please contact your DataHub administrator if this needs corrective action.");
      }

      try {
        _queryService.deleteQuery(queryUrn, authentication);
        return true;
      } catch (Exception e) {
        throw new RuntimeException("Failed to delete Query", e);
      }
    });
  }
}