/*******************************************************************************
 * ============LICENSE_START==================================================
 * * org.onap.dmaap
 * * ===========================================================================
 * * Copyright © 2017 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====================================================
 * *
 * * ECOMP is a trademark and service mark of AT&T Intellectual Property.
 * *
 ******************************************************************************/


package org.onap.dmaap.datarouter.provisioning;

import java.io.IOException;
import java.io.InvalidObjectException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.json.JSONException;
import org.json.JSONObject;
import org.onap.dmaap.datarouter.authz.AuthorizationResponse;
import org.onap.dmaap.datarouter.provisioning.beans.EventLogRecord;
import org.onap.dmaap.datarouter.provisioning.beans.Feed;
import org.onap.dmaap.datarouter.provisioning.eelf.EelfMsgs;

import com.att.eelf.configuration.EELFLogger;
import com.att.eelf.configuration.EELFManager;

import static org.onap.dmaap.datarouter.provisioning.utils.HttpServletUtils.sendResponseError;

/**
 * This servlet handles provisioning for the <feedURL> which is generated by the provisioning
 * server to handle a particular feed. It supports DELETE to mark the feed as deleted,
 * and GET to retrieve information about the feed, and PUT to modify the feed.
 *
 * @author Robert Eby
 * @version $Id$
 */
@SuppressWarnings("serial")
public class FeedServlet extends ProxyServlet {

    //Adding EELF Logger Rally:US664892
    private static EELFLogger eelflogger = EELFManager.getInstance().getLogger("org.onap.dmaap.datarouter.provisioning.FeedServlet");

    /**
     * Delete the Feed at the address /feed/<feednumber>.
     * See the <i>Deleting a Feed</i> section in the <b>Provisioning API</b>
     * document for details on how this method should be invoked.
     */
    @Override
    public void doDelete(HttpServletRequest req, HttpServletResponse resp) {
        setIpAndFqdnForEelf("doDelete");
        eelflogger.info(EelfMsgs.MESSAGE_WITH_BEHALF_AND_FEEDID, req.getHeader(BEHALF_HEADER),getIdFromPath(req)+"");
        EventLogRecord elr = new EventLogRecord(req);
        String message = isAuthorizedForProvisioning(req);
        if (message != null) {
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }
        if (isProxyServer()) {
            super.doDelete(req, resp);
            return;
        }
        String bhdr = req.getHeader(BEHALF_HEADER);
        if (bhdr == null) {
            message = "Missing "+BEHALF_HEADER+" header.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        int feedid = getIdFromPath(req);
        if (feedid < 0) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        Feed feed = Feed.getFeedById(feedid);
        if (feed == null || feed.isDeleted()) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_NOT_FOUND);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_NOT_FOUND, message, eventlogger);
            return;
        }
        // Check with the Authorizer
        AuthorizationResponse aresp = authz.decide(req);
        if (! aresp.isAuthorized()) {
            message = "Policy Engine disallows access.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }

        // Delete FEED table entry (set DELETED flag)
        feed.setDeleted(true);
        if (doUpdate(feed)) {
            activeFeeds--;
            // send response
            elr.setResult(HttpServletResponse.SC_NO_CONTENT);
            eventlogger.info(elr);
            resp.setStatus(HttpServletResponse.SC_NO_CONTENT);
            provisioningDataChanged();
        } else {
            // Something went wrong with the UPDATE
            elr.setResult(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, DB_PROBLEM_MSG, eventlogger);
        }
    }
    /**
     * Get information on the feed at the address /feed/&lt;feednumber&gt;.
     * See the <i>Retrieving Information about a Feed</i> section in the <b>Provisioning API</b>
     * document for details on how this method should be invoked.
     */
    @Override
    public void doGet(HttpServletRequest req, HttpServletResponse resp) {
        setIpAndFqdnForEelf("doGet");
        eelflogger.info(EelfMsgs.MESSAGE_WITH_BEHALF_AND_FEEDID, req.getHeader(BEHALF_HEADER),getIdFromPath(req)+"");
        EventLogRecord elr = new EventLogRecord(req);
        String message = isAuthorizedForProvisioning(req);
        if (message != null) {
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }
        if (isProxyServer()) {
            super.doGet(req, resp);
            return;
        }
        String bhdr = req.getHeader(BEHALF_HEADER);
        if (bhdr == null) {
            message = "Missing "+BEHALF_HEADER+" header.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        int feedid = getIdFromPath(req);
        if (feedid < 0) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        Feed feed = Feed.getFeedById(feedid);
        if (feed == null || feed.isDeleted()) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_NOT_FOUND);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_NOT_FOUND, message, eventlogger);
            return;
        }
        // Check with the Authorizer
        AuthorizationResponse aresp = authz.decide(req);
        if (! aresp.isAuthorized()) {
            message = "Policy Engine disallows access.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }

        // send response
        elr.setResult(HttpServletResponse.SC_OK);
        eventlogger.info(elr);
        resp.setStatus(HttpServletResponse.SC_OK);
        resp.setContentType(FEEDFULL_CONTENT_TYPE);
        try {
            resp.getOutputStream().print(feed.asJSONObject(true).toString());
        } catch (IOException ioe) {
            eventlogger.error("IOException" + ioe.getMessage());
        }
    }
    /**
     * PUT on the &lt;feedURL&gt; for a feed.
     * See the <i>Modifying a Feed</i> section in the <b>Provisioning API</b>
     * document for details on how this method should be invoked.
     */
    @Override
    public void doPut(HttpServletRequest req, HttpServletResponse resp) {
        setIpAndFqdnForEelf("doPut");
        eelflogger.info(EelfMsgs.MESSAGE_WITH_BEHALF_AND_FEEDID, req.getHeader(BEHALF_HEADER),getIdFromPath(req)+"");
        EventLogRecord elr = new EventLogRecord(req);
        String message = isAuthorizedForProvisioning(req);
        if (message != null) {
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }
        if (isProxyServer()) {
            super.doPut(req, resp);
            return;
        }
        String bhdr = req.getHeader(BEHALF_HEADER);
        if (bhdr == null) {
            message = "Missing "+BEHALF_HEADER+" header.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        int feedid = getIdFromPath(req);
        if (feedid < 0) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        Feed oldFeed = Feed.getFeedById(feedid);
        if (oldFeed == null || oldFeed.isDeleted()) {
            message = "Missing or bad feed number.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_NOT_FOUND);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_NOT_FOUND, message, eventlogger);
            return;
        }
        // check content type is FEED_CONTENT_TYPE, version 1.0
        ContentHeader ch = getContentHeader(req);
        String ver = ch.getAttribute("version");
        if (!ch.getType().equals(FEED_BASECONTENT_TYPE) || !(ver.equals("1.0") || ver.equals("2.0"))) {
            message = "Incorrect content-type";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_UNSUPPORTED_MEDIA_TYPE, message, eventlogger);
            return;
        }
        JSONObject jo = getJSONfromInput(req);
        if (jo == null) {
            message = "Badly formed JSON";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        if (intlogger.isDebugEnabled())
            intlogger.debug(jo.toString());
        Feed feed = null;
        try {
            feed = new Feed(jo);
        } catch (InvalidObjectException e) {
            message = e.getMessage();
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        feed.setFeedid(feedid);
        feed.setPublisher(bhdr);    // set from X-ATT-DR-ON-BEHALF-OF header

        String subjectgroup = (req.getHeader("X-ATT-DR-ON-BEHALF-OF-GROUP"));  //Adding for group feature:Rally US708115
        if (!oldFeed.getPublisher().equals(feed.getPublisher()) && subjectgroup == null) {
            message = "This feed must be modified by the same publisher that created it.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        if (!oldFeed.getName().equals(feed.getName())) {
            message = "The name of the feed may not be updated.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        if (!oldFeed.getVersion().equals(feed.getVersion())) {
            message = "The version of the feed may not be updated.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_BAD_REQUEST);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_BAD_REQUEST, message, eventlogger);
            return;
        }
        // Check with the Authorizer
        AuthorizationResponse aresp = authz.decide(req);
        if (! aresp.isAuthorized()) {
            message = "Policy Engine disallows access.";
            elr.setMessage(message);
            elr.setResult(HttpServletResponse.SC_FORBIDDEN);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_FORBIDDEN, message, eventlogger);
            return;
        }

        // Update FEEDS table entries
        if (doUpdate(feed)) {
            // send response
            elr.setResult(HttpServletResponse.SC_OK);
            eventlogger.info(elr);
            resp.setStatus(HttpServletResponse.SC_OK);
            resp.setContentType(FEEDFULL_CONTENT_TYPE);
            try {
                resp.getOutputStream().print(feed.asLimitedJSONObject().toString());
            } catch (IOException ioe) {
                eventlogger.error("IOException" + ioe.getMessage());
            }


            /**Change Owner ship of Feed //Adding for group feature:Rally US708115*/
            if (jo.has("changeowner") && subjectgroup != null) {
                try {
                    Boolean changeowner = (Boolean) jo.get("changeowner");
                    if (changeowner != null && changeowner.equals(true)) {
                        feed.setPublisher(req.getHeader(BEHALF_HEADER));
                        feed.changeOwnerShip();
                    }
                } catch (JSONException je) {
                    eventlogger.error("JSONException" + je.getMessage());
                }
            }
            /***End of change ownership*/

            provisioningDataChanged();
        } else {
            // Something went wrong with the UPDATE
            elr.setResult(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
            eventlogger.info(elr);
            sendResponseError(resp, HttpServletResponse.SC_INTERNAL_SERVER_ERROR, DB_PROBLEM_MSG, eventlogger);
        }
    }
    /**
     * POST on the &lt;feedURL&gt; -- not supported.
     */
    @Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp) {
        setIpAndFqdnForEelf("doPost");
        eelflogger.info(EelfMsgs.MESSAGE_WITH_BEHALF, req.getHeader(BEHALF_HEADER));
        String message = "POST not allowed for the feedURL.";
        EventLogRecord elr = new EventLogRecord(req);
        elr.setMessage(message);
        elr.setResult(HttpServletResponse.SC_METHOD_NOT_ALLOWED);
        eventlogger.info(elr);
        sendResponseError(resp, HttpServletResponse.SC_METHOD_NOT_ALLOWED, message, eventlogger);
    }
}