/*-
 * ============LICENSE_START=======================================================
 * Copyright (C) 2019-2021 AT&T Intellectual Property. All rights reserved.
 * ================================================================================
 * 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.
 * ============LICENSE_END=========================================================
 */

package org.onap.policy.pdp.xacml.application.common.operationshistory;

import com.att.research.xacml.api.XACML3;
import com.att.research.xacml.api.pip.PIPException;
import com.att.research.xacml.api.pip.PIPFinder;
import com.att.research.xacml.api.pip.PIPRequest;
import com.att.research.xacml.api.pip.PIPResponse;
import com.att.research.xacml.std.pip.StdMutablePIPResponse;
import com.att.research.xacml.std.pip.StdPIPResponse;
import com.google.common.base.Strings;
import java.util.Arrays;
import java.util.Collection;
import javax.persistence.NoResultException;
import org.onap.policy.pdp.xacml.application.common.ToscaDictionary;
import org.onap.policy.pdp.xacml.application.common.std.StdOnapPip;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class GetOperationOutcomePip extends StdOnapPip {
    public static final String ISSUER_NAME = "get-operation-outcome";
    private static Logger logger = LoggerFactory.getLogger(GetOperationOutcomePip.class);

    public GetOperationOutcomePip() {
        super();
        this.issuer = ISSUER_NAME;
    }

    @Override
    public Collection<PIPRequest> attributesRequired() {
        return Arrays.asList(PIP_REQUEST_TARGET);
    }

    /**
     * getAttributes.
     *
     * @param pipRequest the request
     * @param pipFinder the pip finder
     * @return PIPResponse
     */
    @Override
    public PIPResponse getAttributes(PIPRequest pipRequest, PIPFinder pipFinder)
        throws PIPException {
        if (this.shutdown) {
            throw new PIPException("Engine is shutdown");
        }
        logger.debug("getAttributes requesting attribute {} of type {} for issuer {}",
            pipRequest.getAttributeId(), pipRequest.getDataTypeId(), pipRequest.getIssuer());
        //
        // Determine if the issuer is correct
        //
        if (Strings.isNullOrEmpty(pipRequest.getIssuer())) {
            logger.error("issuer is null - returning empty response");
            //
            // We only respond to ourself as the issuer
            //
            return StdPIPResponse.PIP_RESPONSE_EMPTY;
        }
        if (!pipRequest.getIssuer().startsWith(ToscaDictionary.GUARD_ISSUER_PREFIX)) {
            logger.error("Issuer does not start with guard");
            //
            // We only respond to ourself as the issuer
            //
            return StdPIPResponse.PIP_RESPONSE_EMPTY;
        }
        //
        // Parse out the issuer which denotes the time window
        // Eg: any-prefix:clname:some-controlloop-name
        //
        String[] s1 = pipRequest.getIssuer().split("clname:");
        String clname = s1[1];
        String target = null;
        target = getAttribute(pipFinder, PIP_REQUEST_TARGET);

        logger.debug("Going to query DB about: clname={}, target={}", clname, target);
        String outcome = doDatabaseQuery(clname);
        logger.info("Query result is: {}", outcome);

        var pipResponse = new StdMutablePIPResponse();
        this.addStringAttribute(pipResponse, XACML3.ID_ATTRIBUTE_CATEGORY_RESOURCE,
            ToscaDictionary.ID_RESOURCE_GUARD_OPERATIONOUTCOME, outcome, pipRequest);
        return new StdPIPResponse(pipResponse);
    }

    private String doDatabaseQuery(String clname) {
        logger.info("Querying operations history for {}", clname);
        //
        // Only can query if we have an EntityManager
        //
        if (em == null) {
            logger.error("No EntityManager available");
            return null;
        }
        //
        // Do the query
        //
        try {
            //
            // We are expecting a single result
            //
            String result = em
                .createQuery("select e.outcome from OperationsHistory e" + " where e.closedLoopName= ?1"
                    + " order by e.starttime desc", String.class)
                .setParameter(1, clname).setMaxResults(1).getSingleResult();

            // Check the value of result
            if (result.equalsIgnoreCase("Started")) {
                return ("In_Progress");
            } else {
                return ("Complete");
            }
        } catch (NoResultException e) {
            logger.trace("No results", e);
        } catch (Exception e) {
            logger.error("Typed query failed", e);
        }
        return null;
    }
}