/*
 * Copyright (c) 2004-2022, University of Oslo
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * Neither the name of the HISP project nor the names of its contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.hisp.dhis.dxf2.deprecated.tracker.event;

import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.stream.Collectors;
import lombok.RequiredArgsConstructor;
import org.apache.commons.lang3.tuple.Pair;
import org.hisp.dhis.common.IdentifiableObject;
import org.hisp.dhis.dxf2.deprecated.tracker.report.EventRow;
import org.hisp.dhis.dxf2.deprecated.tracker.trackedentity.TrackedEntityInstanceService;
import org.hisp.dhis.dxf2.deprecated.tracker.trackedentity.TrackedEntityOuInfo;
import org.hisp.dhis.dxf2.deprecated.tracker.trackedentity.TrackedEntityProgramOwnerIds;
import org.hisp.dhis.organisationunit.OrganisationUnit;
import org.hisp.dhis.organisationunit.OrganisationUnitService;
import org.hisp.dhis.program.Program;
import org.hisp.dhis.program.ProgramService;
import org.hisp.dhis.trackedentity.TrackedEntityProgramOwnerService;
import org.springframework.stereotype.Service;

@Service
@RequiredArgsConstructor
public class EventServiceContextBuilder {

  private final TrackedEntityInstanceService entityInstanceService;

  private final ProgramService programService;

  private final TrackedEntityProgramOwnerService trackedEntityProgramOwnerService;

  private final OrganisationUnitService organisationUnitService;

  public EventContext build(List<EventRow> eventRowList) {
    Map<String, List<EventRow>> eventsByProgramUid =
        eventRowList.stream().collect(Collectors.groupingBy(EventRow::getProgram));

    List<String> trackedEntityInstanceUids =
        eventRowList.stream()
            .map(EventRow::getTrackedEntityInstance)
            .filter(Objects::nonNull)
            .distinct()
            .collect(Collectors.toList());

    Map<String, TrackedEntityOuInfo> trackedEntityInstanceByUid =
        entityInstanceService.getTrackedEntityOuInfoByUid(trackedEntityInstanceUids).stream()
            .collect(
                Collectors.toMap(
                    TrackedEntityOuInfo::trackedEntityUid,
                    trackedEntityOuInfo -> trackedEntityOuInfo));

    Map<String, Program> programsByUid =
        programService
            .getPrograms(
                eventRowList.stream().map(EventRow::getProgram).collect(Collectors.toSet()))
            .stream()
            .collect(Collectors.toMap(IdentifiableObject::getUid, program -> program));

    Map<Pair<String, String>, String> orgUnitByTeiUidAndProgramUidPairs =
        eventsByProgramUid.keySet().stream()
            .flatMap(
                programUid ->
                    entityInstanceService
                        .getTrackedEntityProgramOwnersUidsUsingId(
                            eventsByProgramUid.get(programUid).stream()
                                .map(EventRow::getTrackedEntityInstance)
                                .filter(Objects::nonNull)
                                .map(trackedEntityInstanceByUid::get)
                                .map(TrackedEntityOuInfo::trackerEntityId)
                                .distinct()
                                .collect(Collectors.toList()),
                            programsByUid.get(programUid))
                        .stream())
            .collect(
                Collectors.toMap(
                    trackedEntityProgramOwnerIds ->
                        Pair.of(
                            trackedEntityProgramOwnerIds.getTrackedEntityUid(),
                            trackedEntityProgramOwnerIds.getProgramUid()),
                    TrackedEntityProgramOwnerIds::getOrgUnitUid));

    Map<String, OrganisationUnit> orgUnitsByUid =
        organisationUnitService
            .getOrganisationUnitsByUid(orgUnitByTeiUidAndProgramUidPairs.values())
            .stream()
            .collect(Collectors.toMap(IdentifiableObject::getUid, ou -> ou));

    return new EventContext(
        trackedEntityInstanceByUid,
        programsByUid,
        orgUnitByTeiUidAndProgramUidPairs,
        orgUnitsByUid);
  }
}
