/*-
 * ============LICENSE_START=======================================================
 * Copyright (C) 2019 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.
 *
 * SPDX-License-Identifier: Apache-2.0
 * ============LICENSE_END=========================================================
 */

package org.onap.policy.pdpx.main.rest.provider;

import javax.ws.rs.core.Response.Status;

import org.onap.policy.models.decisions.concepts.DecisionException;
import org.onap.policy.models.decisions.concepts.DecisionRequest;
import org.onap.policy.models.decisions.concepts.DecisionResponse;
import org.onap.policy.pdp.xacml.application.common.XacmlApplicationServiceProvider;
import org.onap.policy.pdpx.main.rest.XacmlPdpApplicationManager;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


public class DecisionProvider {
    private static final Logger LOGGER = LoggerFactory.getLogger(DecisionProvider.class);

    /**
     * Retrieves the policy decision for the specified parameters.
     * @param body
     *
     * @return the Decision object
     */
    public DecisionResponse fetchDecision(DecisionRequest request) {
        LOGGER.debug("Fetching decision {}", request);
        //
        // Find application for this decision
        //
        XacmlApplicationServiceProvider application = findApplication(request);
        //
        // Cannot find application for action
        //
        return application.makeDecision(request);
    }

    private XacmlApplicationServiceProvider findApplication(DecisionRequest request) {
        XacmlApplicationServiceProvider application = XacmlPdpApplicationManager.findApplication(request);
        if (application != null) {
            return application;
        }
        throw new DecisionException(Status.BAD_REQUEST, "No application for action " + request.getAction());
    }

}