/*-
 * ============LICENSE_START=======================================================
 *  Copyright (C) 2019 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.policy.models.tosca.authorative.provider;

import java.util.ArrayList;
import java.util.Collections;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

import lombok.NonNull;

import org.onap.policy.models.base.PfConceptKey;
import org.onap.policy.models.base.PfModelException;
import org.onap.policy.models.dao.PfDao;
import org.onap.policy.models.tosca.authorative.concepts.ToscaEntity;
import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicy;
import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicyFilter;
import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicyType;
import org.onap.policy.models.tosca.authorative.concepts.ToscaPolicyTypeFilter;
import org.onap.policy.models.tosca.authorative.concepts.ToscaServiceTemplate;
import org.onap.policy.models.tosca.simple.concepts.JpaToscaServiceTemplate;
import org.onap.policy.models.tosca.simple.provider.SimpleToscaProvider;

/**
 * This class provides the provision of information on TOSCA concepts in the database to callers.
 *
 * @author Liam Fallon (liam.fallon@est.tech)
 */
public class AuthorativeToscaProvider {
    /**
     * Get policy types.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy type to get.
     * @param version the version of the policy type to get.
     * @return the policy types found
     * @throws PfModelException on errors getting policy types
     */
    public ToscaServiceTemplate getPolicyTypes(@NonNull final PfDao dao, final String name, final String version)
            throws PfModelException {

        return new SimpleToscaProvider().getPolicyTypes(dao, name, version).toAuthorative();
    }

    /**
     * Get policy types.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy type to get, set to null to get all policy types
     * @param version the version of the policy type to get, set to null to get all versions
     * @return the policy types found
     * @throws PfModelException on errors getting policy types
     */
    public List<ToscaPolicyType> getPolicyTypeList(@NonNull final PfDao dao, final String name, final String version)
            throws PfModelException {

        return (asConceptList(
                new SimpleToscaProvider().getPolicyTypes(dao, name, version).toAuthorative().getPolicyTypes()));
    }

    /**
     * Get filtered policy types.
     *
     * @param dao the DAO to use to access the database
     * @param filter the filter for the policy types to get
     * @return the policy types found
     * @throws PfModelException on errors getting policy types
     */
    public ToscaServiceTemplate getFilteredPolicyTypes(@NonNull final PfDao dao,
            @NonNull final ToscaPolicyTypeFilter filter) throws PfModelException {

        ToscaServiceTemplate serviceTemplate =
                new SimpleToscaProvider().getPolicyTypes(dao, null, null).toAuthorative();

        List<ToscaPolicyType> filteredPolicyTypes = asConceptList(serviceTemplate.getPolicyTypes());
        filteredPolicyTypes = filter.filter(filteredPolicyTypes);

        serviceTemplate.setPolicyTypes(asConceptMap(filteredPolicyTypes));

        return serviceTemplate;
    }

    /**
     * Get filtered policy types.
     *
     * @param dao the DAO to use to access the database
     * @param filter the filter for the policy types to get
     * @return the policy types found
     * @throws PfModelException on errors getting policy types
     */
    public List<ToscaPolicyType> getFilteredPolicyTypeList(@NonNull final PfDao dao,
            @NonNull final ToscaPolicyTypeFilter filter) throws PfModelException {

        return filter.filter(getPolicyTypeList(dao, null, null));
    }

    /**
     * Create policy types.
     *
     * @param dao the DAO to use to access the database
     * @param serviceTemplate the service template containing the definition of the policy types to be created
     * @return the TOSCA service template containing the created policy types
     * @throws PfModelException on errors creating policy types
     */
    public ToscaServiceTemplate createPolicyTypes(@NonNull final PfDao dao,
            @NonNull final ToscaServiceTemplate serviceTemplate) throws PfModelException {

        return new SimpleToscaProvider().createPolicyTypes(dao, new JpaToscaServiceTemplate(serviceTemplate))
                .toAuthorative();
    }

    /**
     * Update policy types.
     *
     * @param dao the DAO to use to access the database
     * @param serviceTemplate the service template containing the definition of the policy types to be modified
     * @return the TOSCA service template containing the modified policy types
     * @throws PfModelException on errors updating policy types
     */
    public ToscaServiceTemplate updatePolicyTypes(@NonNull final PfDao dao,
            @NonNull final ToscaServiceTemplate serviceTemplate) throws PfModelException {

        return new SimpleToscaProvider().updatePolicyTypes(dao, new JpaToscaServiceTemplate(serviceTemplate))
                .toAuthorative();
    }

    /**
     * Delete policy type.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy type to delete.
     * @param version the version of the policy type to delete.
     * @return the TOSCA service template containing the policy type that was deleted
     * @throws PfModelException on errors deleting policy types
     */
    public ToscaServiceTemplate deletePolicyType(@NonNull final PfDao dao, @NonNull final String name,
            @NonNull final String version) throws PfModelException {

        return new SimpleToscaProvider().deletePolicyType(dao, new PfConceptKey(name, version)).toAuthorative();
    }

    /**
     * Get policies.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy to get.
     * @param version the version of the policy to get.
     * @return the policies found
     * @throws PfModelException on errors getting policies
     */
    public ToscaServiceTemplate getPolicies(@NonNull final PfDao dao, final String name, final String version)
            throws PfModelException {

        return new SimpleToscaProvider().getPolicies(dao, name, version).toAuthorative();
    }

    /**
     * Get policies.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy to get, null to get all policies
     * @param version the version of the policy to get, null to get all versions of a policy
     * @return the policies found
     * @throws PfModelException on errors getting policies
     */
    public List<ToscaPolicy> getPolicyList(@NonNull final PfDao dao, final String name, final String version)
            throws PfModelException {

        return asConceptList(new SimpleToscaProvider().getPolicies(dao, name, version).toAuthorative()
                .getToscaTopologyTemplate().getPolicies());
    }

    /**
     * Get filtered policies.
     *
     * @param dao the DAO to use to access the database
     * @param filter the filter for the policies to get
     * @return the policies found
     * @throws PfModelException on errors getting policies
     */
    public ToscaServiceTemplate getFilteredPolicies(@NonNull final PfDao dao, @NonNull final ToscaPolicyFilter filter)
            throws PfModelException {

        ToscaServiceTemplate serviceTemplate = new SimpleToscaProvider().getPolicies(dao, null, null).toAuthorative();

        List<ToscaPolicy> filteredPolicies = asConceptList(serviceTemplate.getToscaTopologyTemplate().getPolicies());
        filteredPolicies = filter.filter(filteredPolicies);

        serviceTemplate.getToscaTopologyTemplate().setPolicies(asConceptMap(filteredPolicies));

        return serviceTemplate;
    }

    /**
     * Get filtered policies.
     *
     * @param dao the DAO to use to access the database
     * @param filter the filter for the policies to get
     * @return the policies found
     * @throws PfModelException on errors getting policies
     */
    public List<ToscaPolicy> getFilteredPolicyList(@NonNull final PfDao dao, @NonNull final ToscaPolicyFilter filter)
            throws PfModelException {

        return filter.filter(getPolicyList(dao, null, null));
    }

    /**
     * Create policies.
     *
     * @param dao the DAO to use to access the database
     * @param serviceTemplate the service template containing the definitions of the new policies to be created.
     * @return the TOSCA service template containing the policy types that were created
     * @throws PfModelException on errors creating policies
     */
    public ToscaServiceTemplate createPolicies(@NonNull final PfDao dao,
            @NonNull final ToscaServiceTemplate serviceTemplate) throws PfModelException {

        return new SimpleToscaProvider().createPolicies(dao, new JpaToscaServiceTemplate(serviceTemplate))
                .toAuthorative();
    }

    /**
     * Update policies.
     *
     * @param dao the DAO to use to access the database
     * @param serviceTemplate the service template containing the definitions of the policies to be updated.
     * @return the TOSCA service template containing the policies that were updated
     * @throws PfModelException on errors updating policies
     */
    public ToscaServiceTemplate updatePolicies(@NonNull final PfDao dao,
            @NonNull final ToscaServiceTemplate serviceTemplate) throws PfModelException {

        return new SimpleToscaProvider().updatePolicies(dao, new JpaToscaServiceTemplate(serviceTemplate))
                .toAuthorative();
    }

    /**
     * Delete policy.
     *
     * @param dao the DAO to use to access the database
     * @param name the name of the policy to delete.
     * @param version the version of the policy to delete.
     * @return the TOSCA service template containing the policy that weas deleted
     * @throws PfModelException on errors deleting policies
     */
    public ToscaServiceTemplate deletePolicy(@NonNull final PfDao dao, @NonNull final String name,
            @NonNull final String version) throws PfModelException {

        return new SimpleToscaProvider().deletePolicy(dao, new PfConceptKey(name, version)).toAuthorative();
    }

    /**
     * Return the contents of a list of maps as a plain list.
     *
     * @param listOfMaps the list of maps
     * @return the plain list
     */
    private <T> List<T> asConceptList(final List<Map<String, T>> listOfMaps) {
        List<T> returnList = new ArrayList<>();
        for (Map<String, T> conceptMap : listOfMaps) {
            for (T concept : conceptMap.values()) {
                returnList.add(concept);
            }
        }

        return returnList;
    }

    /**
     * Return the contents of a list of concepts as a list of maps of concepts.
     *
     * @param comceptList the concept list
     * @return the concept map
     */
    private <T extends ToscaEntity> List<Map<String, T>> asConceptMap(List<T> conceptList) {
        Map<String, T> conceptMap = new LinkedHashMap<>();
        for (T concept : conceptList) {
            conceptMap.put(concept.getName(), concept);
        }

        return Collections.singletonList(conceptMap);
    }
}