/*
    * This file is part of Waarp Project (named also Waarp or GG).
    *
    *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
    *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
    * individual contributors.
    *
    *  All Waarp Project is free software: you can redistribute it and/or
    * modify it under the terms of the GNU General Public License as published by
   * the Free Software Foundation, either version 3 of the License, or (at your
   * option) any later version.
   *
   * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
   * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License along with
   * Waarp . If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.waarp.openr66.protocol.http.restv2.dbhandlers;
  
  import com.fasterxml.jackson.databind.node.ObjectNode;
  import io.cdap.http.HttpResponder;
  import io.netty.handler.codec.http.DefaultHttpHeaders;
  import io.netty.handler.codec.http.HttpHeaders;
  import io.netty.handler.codec.http.HttpMethod;
  import io.netty.handler.codec.http.HttpRequest;
  import org.waarp.openr66.dao.DAOFactory;
  import org.waarp.openr66.dao.LimitDAO;
  import org.waarp.openr66.dao.exception.DAOConnectionException;
  import org.waarp.openr66.dao.exception.DAONoDataException;
  import org.waarp.openr66.pojo.Limit;
  import org.waarp.openr66.protocol.http.restv2.converters.LimitsConverter;
  import org.waarp.openr66.protocol.http.restv2.errors.RestErrorException;
  import org.waarp.openr66.protocol.http.restv2.utils.JsonUtils;
  
  import javax.ws.rs.Consumes;
  import javax.ws.rs.DELETE;
  import javax.ws.rs.GET;
  import javax.ws.rs.InternalServerErrorException;
  import javax.ws.rs.OPTIONS;
  import javax.ws.rs.POST;
  import javax.ws.rs.PUT;
  import javax.ws.rs.Path;
  import java.util.ArrayList;
  import java.util.List;
  
  import static io.netty.handler.codec.http.HttpResponseStatus.*;
  import static javax.ws.rs.core.HttpHeaders.*;
  import static javax.ws.rs.core.MediaType.*;
  import static org.waarp.common.role.RoleDefault.ROLE.*;
  import static org.waarp.openr66.protocol.configuration.Configuration.*;
  import static org.waarp.openr66.protocol.http.restv2.RestConstants.*;
  import static org.waarp.openr66.protocol.http.restv2.errors.RestErrors.*;
  
  /**
   * This is the {@link AbstractRestDbHandler} handling all requests made on the
   * bandwidth limits REST entry
   * point.
   */
  @Path(LIMITS_HANDLER_URI)
  public class LimitsHandler extends AbstractRestDbHandler {
  
    /**
     * The content of the 'Allow' header sent when an 'OPTIONS' request is made
     * on the handler.
     */
    private static final HttpHeaders OPTIONS_HEADERS;
  
    static {
      OPTIONS_HEADERS = new DefaultHttpHeaders();
      final List<HttpMethod> allow = new ArrayList<HttpMethod>();
      allow.add(HttpMethod.GET);
      allow.add(HttpMethod.POST);
      allow.add(HttpMethod.PUT);
      allow.add(HttpMethod.DELETE);
      allow.add(HttpMethod.OPTIONS);
      OPTIONS_HEADERS.add(ALLOW, allow);
    }
  
    /**
     * Initializes the handler with the given CRUD mask.
     *
     * @param crud the CRUD mask for this handler
     */
    public LimitsHandler(final byte crud) {
      super(crud);
    }
  
    /**
     * Method called to obtain a description of the host's current bandwidth
     * limits.
     *
     * @param request the HttpRequest made on the resource
     * @param responder the HttpResponder which sends the reply to the
     *     request
     */
    @GET
   @Consumes(WILDCARD)
   @RequiredRole(LIMIT)
   public final void getLimits(final HttpRequest request,
                               final HttpResponder responder) {
     LimitDAO limitDAO = null;
     try {
       limitDAO = DAO_FACTORY.getLimitDAO(true);
       final String host = serverName();
       if (limitDAO.exist(host)) {
         final Limit limits = limitDAO.select(host);
         final ObjectNode responseObject = LimitsConverter.limitToNode(limits);
         final String responseText = JsonUtils.nodeToString(responseObject);
         responder.sendJson(OK, responseText);
       } else {
         responder.sendStatus(NOT_FOUND);
       }
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } catch (final DAONoDataException e) {
       responder.sendStatus(NOT_FOUND);
     } finally {
       DAOFactory.closeDAO(limitDAO);
     }
   }
 
   /**
    * Method called to initiate the entry for this host in the bandwidth limits
    * database. If the host already has
    * limits set in its configuration, they will be replaced by these new
    * ones.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    */
   @POST
   @Consumes(APPLICATION_JSON)
   @RequiredRole(READONLY)
   public final void initializeLimits(final HttpRequest request,
                                      final HttpResponder responder) {
     LimitDAO limitDAO = null;
     try {
       limitDAO = DAO_FACTORY.getLimitDAO(false);
 
       if (!limitDAO.exist(serverName())) {
         final ObjectNode requestObject = JsonUtils.deserializeRequest(request);
         checkSanity(requestObject);
         final Limit limits = LimitsConverter.nodeToNewLimit(requestObject);
         limitDAO.insert(limits);
 
         configuration.changeNetworkLimit(limits.getReadGlobalLimit(),
                                          limits.getWriteGlobalLimit(),
                                          limits.getReadSessionLimit(),
                                          limits.getWriteSessionLimit(),
                                          limits.getDelayLimit());
 
         final ObjectNode responseObject = LimitsConverter.limitToNode(limits);
         final String responseText = JsonUtils.nodeToString(responseObject);
         responder.sendJson(CREATED, responseText);
       } else {
         throw new RestErrorException(ALREADY_EXISTING(serverName()));
       }
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } finally {
       DAOFactory.closeDAO(limitDAO);
     }
   }
 
   /**
    * Method called to update this host's bandwidth limits in the database and
    * configuration.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    */
   @PUT
   @Consumes(APPLICATION_JSON)
   @RequiredRole(LIMIT)
   public final void updateLimits(final HttpRequest request,
                                  final HttpResponder responder) {
     LimitDAO limitDAO = null;
     try {
       limitDAO = DAO_FACTORY.getLimitDAO(false);
 
       if (!limitDAO.exist(serverName())) {
         responder.sendStatus(NOT_FOUND);
         return;
       }
 
       final ObjectNode requestObject = JsonUtils.deserializeRequest(request);
       checkSanity(requestObject);
       final Limit oldLimits = limitDAO.select(serverName());
       final Limit newLimits =
           LimitsConverter.nodeToUpdatedLimit(requestObject, oldLimits);
 
       limitDAO.update(newLimits);
 
       configuration.changeNetworkLimit(newLimits.getReadGlobalLimit(),
                                        newLimits.getWriteGlobalLimit(),
                                        newLimits.getReadSessionLimit(),
                                        newLimits.getWriteSessionLimit(),
                                        newLimits.getDelayLimit());
 
       final ObjectNode responseObject = LimitsConverter.limitToNode(newLimits);
       final String responseText = JsonUtils.nodeToString(responseObject);
       responder.sendJson(CREATED, responseText);
 
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } catch (final DAONoDataException e) {
       responder.sendStatus(NOT_FOUND);
     } finally {
       DAOFactory.closeDAO(limitDAO);
     }
   }
 
   /**
    * Method called to remove any bandwidth limits in place on this host. Also
    * removes any limits set in the
    * configuration.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    */
   @DELETE
   @Consumes(WILDCARD)
   @RequiredRole(LIMIT)
   public final void deleteLimits(final HttpRequest request,
                                  final HttpResponder responder) {
     LimitDAO limitDAO = null;
     try {
       limitDAO = DAO_FACTORY.getLimitDAO(false);
 
       if (limitDAO.exist(serverName())) {
         limitDAO.delete(limitDAO.select(serverName()));
         configuration.changeNetworkLimit(0, 0, 0, 0, 0);
         responder.sendStatus(NO_CONTENT);
       } else {
         responder.sendStatus(NOT_FOUND);
       }
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } catch (final DAONoDataException e) {
       responder.sendStatus(NOT_FOUND);
     } finally {
       DAOFactory.closeDAO(limitDAO);
     }
   }
 
   /**
    * Method called to get a list of all allowed HTTP methods on this entry
    * point. The HTTP methods are sent as
    * an array in the reply's headers.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    */
   @OPTIONS
   @Consumes(WILDCARD)
   @RequiredRole(NOACCESS)
   public final void options(final HttpRequest request,
                             final HttpResponder responder) {
     responder.sendStatus(OK, OPTIONS_HEADERS);
   }
 }