/*
 *  ============LICENSE_START=======================================================
 *  Copyright (C) 2022-2024 Nordix Foundation
 *  ================================================================================
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  SPDX-License-Identifier: Apache-2.0
 *  ============LICENSE_END=========================================================
 */

package org.onap.cps.ncmp.api.impl.inventory.sync;

import static org.onap.cps.ncmp.api.impl.ncmppersistence.NcmpPersistence.NCMP_DATASPACE_NAME;
import static org.onap.cps.ncmp.api.impl.ncmppersistence.NcmpPersistence.NCMP_DMI_REGISTRY_ANCHOR;
import static org.onap.cps.ncmp.api.impl.ncmppersistence.NcmpPersistence.NCMP_DMI_REGISTRY_PARENT;
import static org.onap.cps.ncmp.api.impl.ncmppersistence.NcmpPersistence.NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME;

import java.time.OffsetDateTime;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.tuple.ImmutableTriple;
import org.onap.cps.api.CpsAnchorService;
import org.onap.cps.api.CpsDataService;
import org.onap.cps.api.CpsModuleService;
import org.onap.cps.ncmp.api.impl.inventory.CmHandleQueries;
import org.onap.cps.ncmp.api.impl.inventory.CmHandleState;
import org.onap.cps.ncmp.api.impl.operations.DmiModelOperations;
import org.onap.cps.ncmp.api.impl.utils.YangDataConverter;
import org.onap.cps.ncmp.api.impl.yangmodels.YangModelCmHandle;
import org.onap.cps.spi.CascadeDeleteAllowed;
import org.onap.cps.spi.FetchDescendantsOption;
import org.onap.cps.spi.exceptions.SchemaSetNotFoundException;
import org.onap.cps.spi.model.DataNode;
import org.onap.cps.spi.model.ModuleReference;
import org.onap.cps.utils.JsonObjectMapper;
import org.springframework.stereotype.Service;

@Slf4j
@Service
@RequiredArgsConstructor
public class ModuleSyncService {

    private final DmiModelOperations dmiModelOperations;
    private final CpsModuleService cpsModuleService;
    private final CmHandleQueries cmHandleQueries;
    private final CpsDataService cpsDataService;
    private final CpsAnchorService cpsAnchorService;
    private final JsonObjectMapper jsonObjectMapper;
    private static final Map<String, String> NO_NEW_MODULES = Collections.emptyMap();

    /**
     * This method registers a cm handle and initiates modules sync.
     *
     * @param yangModelCmHandle the yang model of cm handle.
     */
    public void syncAndCreateOrUpgradeSchemaSetAndAnchor(final YangModelCmHandle yangModelCmHandle) {

        final boolean inUpgrade = ModuleOperationsUtils.inUpgradeOrUpgradeFailed(yangModelCmHandle.getCompositeState());

        final ImmutableTriple<String, Map<String, String>, Collection<ModuleReference>>
                allModuleReferencesAndNewModuleNameByModuleSetTag
                = getAllModuleReferencesAndNewYangResourcesByModuleSetTag(yangModelCmHandle, inUpgrade);

        final String moduleSetTag = allModuleReferencesAndNewModuleNameByModuleSetTag.getLeft();
        final Map<String, String> newYangResources = allModuleReferencesAndNewModuleNameByModuleSetTag.getMiddle();
        final Collection<ModuleReference> allModuleReferences
                = allModuleReferencesAndNewModuleNameByModuleSetTag.getRight();
        final String cmHandleId = yangModelCmHandle.getId();

        if (inUpgrade) {
            cpsModuleService.upgradeSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId,
                    newYangResources, allModuleReferences);
            setCmHandleModuleSetTag(yangModelCmHandle, moduleSetTag);
        } else {
            cpsModuleService.createSchemaSetFromModules(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId,
                    newYangResources, allModuleReferences);
            cpsAnchorService.createAnchor(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleId, cmHandleId);
        }
    }

    /**
     * Deletes the SchemaSet for schema set id if the SchemaSet Exists.
     *
     * @param schemaSetId the schema set id to be deleted
     */
    public void deleteSchemaSetIfExists(final String schemaSetId) {
        try {
            cpsModuleService.deleteSchemaSet(NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, schemaSetId,
                CascadeDeleteAllowed.CASCADE_DELETE_ALLOWED);
            log.debug("SchemaSet for {} has been deleted. Ready to be recreated.", schemaSetId);
        } catch (final SchemaSetNotFoundException e) {
            log.debug("No SchemaSet for {}. Assuming CmHandle has not been previously Module Synced.", schemaSetId);
        }
    }

    private ImmutableTriple<String, Map<String, String>, Collection<ModuleReference>>
        getAllModuleReferencesAndNewYangResourcesByModuleSetTag(final YangModelCmHandle yangModelCmHandle,
                                                                final boolean inUpgrade) {
        final String moduleSetTag = getModuleSetTag(yangModelCmHandle, inUpgrade);
        final Collection<ModuleReference> allModuleReferences;
        final Map<String, String> newYangResources;

        final YangModelCmHandle cmHandleWithSameModuleSetTag = getAnyReadyCmHandleByModuleSetTag(moduleSetTag);
        if (cmHandleWithSameModuleSetTag == null) {
            allModuleReferences = dmiModelOperations.getModuleReferences(yangModelCmHandle);
            newYangResources = getNewModuleNameToContentMap(yangModelCmHandle, allModuleReferences);
        } else {
            log.info("Found other cm handle having same module set tag: {}", moduleSetTag);
            allModuleReferences = cpsModuleService.getYangResourcesModuleReferences(
                    NFP_OPERATIONAL_DATASTORE_DATASPACE_NAME, cmHandleWithSameModuleSetTag.getId());
            newYangResources = NO_NEW_MODULES;
        }
        return ImmutableTriple.of(moduleSetTag, newYangResources, allModuleReferences);
    }

    private YangModelCmHandle getAnyReadyCmHandleByModuleSetTag(final String moduleSetTag) {
        if (StringUtils.isBlank(moduleSetTag)) {
            return null;
        }
        final String escapedModuleSetTag = moduleSetTag.replace("'", "''");
        final List<DataNode> dataNodes = cmHandleQueries.queryNcmpRegistryByCpsPath(
                NCMP_DMI_REGISTRY_PARENT + "/cm-handles[@module-set-tag='" + escapedModuleSetTag + "']",
                FetchDescendantsOption.DIRECT_CHILDREN_ONLY);
        return dataNodes.stream().map(YangDataConverter::convertCmHandleToYangModel)
                .filter(cmHandle -> cmHandle.getCompositeState().getCmHandleState() == CmHandleState.READY)
                .findFirst().orElse(null);
    }

    private void setCmHandleModuleSetTag(final YangModelCmHandle upgradedCmHandle, final String moduleSetTag) {
        final Map<String, Map<String, String>> dmiRegistryProperties = new HashMap<>(1);
        final Map<String, String> cmHandleProperties = new HashMap<>(2);
        cmHandleProperties.put("id", upgradedCmHandle.getId());
        cmHandleProperties.put("module-set-tag", moduleSetTag);
        dmiRegistryProperties.put("cm-handles", cmHandleProperties);
        cpsDataService.updateNodeLeaves(NCMP_DATASPACE_NAME, NCMP_DMI_REGISTRY_ANCHOR, NCMP_DMI_REGISTRY_PARENT,
                jsonObjectMapper.asJsonString(dmiRegistryProperties), OffsetDateTime.now());
    }

    private Map<String, String> getNewModuleNameToContentMap(final YangModelCmHandle yangModelCmHandle,
                                                             final Collection<ModuleReference> moduleReferences) {
        final Collection<ModuleReference> identifiedNewModuleReferences = cpsModuleService
                .identifyNewModuleReferences(moduleReferences);
        return dmiModelOperations.getNewYangResourcesFromDmi(yangModelCmHandle, identifiedNewModuleReferences);
    }

    private String getModuleSetTag(final YangModelCmHandle yangModelCmHandle, final boolean inUpgrade) {
        if (inUpgrade) {
            return ModuleOperationsUtils.getUpgradedModuleSetTagFromLockReason(
                    yangModelCmHandle.getCompositeState().getLockReason());
        }
        return yangModelCmHandle.getModuleSetTag();
    }

}