/*
    * 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.Filter;
  import org.waarp.openr66.dao.HostDAO;
  import org.waarp.openr66.dao.TransferDAO;
  import org.waarp.openr66.dao.exception.DAOConnectionException;
  import org.waarp.openr66.dao.exception.DAONoDataException;
  import org.waarp.openr66.database.data.DbTaskRunner.Columns;
  import org.waarp.openr66.pojo.Host;
  import org.waarp.openr66.protocol.configuration.Configuration;
  import org.waarp.openr66.protocol.http.restv2.converters.HostConverter;
  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.PUT;
  import javax.ws.rs.Path;
  import javax.ws.rs.PathParam;
  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.HOST;
  import static org.waarp.common.role.RoleDefault.ROLE.*;
  import static org.waarp.openr66.protocol.http.restv2.RestConstants.*;
  
  /**
   * This is the {@link AbstractRestDbHandler} handling all requests made on the
   * single host REST entry point.
   */
  @Path(HOST_ID_HANDLER_URI)
  public class HostIdHandler 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.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 HostIdHandler(final byte crud) {
      super(crud);
    }
  
    /**
     * Method called to retrieve a host entry from the database with the id in
     * the request URI.
     *
     * @param request the HttpRequest made on the resource
     * @param responder the HttpResponder which sends the reply to the
     *     request
     * @param id the requested host's name
     */
   @GET
   @Consumes(WILDCARD)
   @RequiredRole(READONLY)
   public final void getHost(final HttpRequest request,
                             final HttpResponder responder,
                             @PathParam(URI_ID) final String id) {
     checkSanity(id);
     HostDAO hostDAO = null;
     try {
       hostDAO = DAO_FACTORY.getHostDAO(true);
       final Host host = hostDAO.select(id);
       if (host == null) {
         responder.sendStatus(NOT_FOUND);
         return;
       }
       final ObjectNode responseObject = HostConverter.hostToNode(host);
       final String responseText = JsonUtils.nodeToString(responseObject);
       responder.sendJson(OK, responseText);
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } catch (final DAONoDataException e) {
       responder.sendStatus(NOT_FOUND);
     } finally {
       DAOFactory.closeDAO(hostDAO);
     }
   }
 
   /**
    * Method called to update the host entry with the given id. The entry is
    * replaced by the one in the request's
    * body.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    * @param id the requested host's name
    */
   @PUT
   @Consumes(APPLICATION_JSON)
   @RequiredRole(HOST)
   public final void updateHost(final HttpRequest request,
                                final HttpResponder responder,
                                @PathParam(URI_ID) final String id) {
     checkSanity(id);
     HostDAO hostDAO = null;
     try {
       hostDAO = DAO_FACTORY.getHostDAO(false);
       final Host oldHost = hostDAO.select(id);
 
       if (oldHost == null) {
         responder.sendStatus(NOT_FOUND);
         return;
       }
 
       final ObjectNode requestObject = JsonUtils.deserializeRequest(request);
       checkSanity(requestObject);
       final Host newHost =
           HostConverter.nodeToUpdatedHost(requestObject, oldHost);
 
       hostDAO.update(newHost);
 
       final ObjectNode responseObject = HostConverter.hostToNode(newHost);
       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(hostDAO);
     }
   }
 
   /**
    * Method called to delete a host entry from the database.
    * Note that if the host is used in any related Transfers, or if the host
    * is the current host, the delete
    * cannot be achieved and NOT_FOUND will be returned.
    *
    * @param request the HttpRequest made on the resource
    * @param responder the HttpResponder which sends the reply to the
    *     request
    * @param id the requested host's name
    */
   @DELETE
   @Consumes(WILDCARD)
   @RequiredRole(HOST)
   public final void deleteHost(final HttpRequest request,
                                final HttpResponder responder,
                                @PathParam(URI_ID) final String id) {
     checkSanity(id);
     HostDAO hostDAO = null;
     try {
       hostDAO = DAO_FACTORY.getHostDAO(false);
       final Host host = hostDAO.select(id);
       if (host == null) {
         responder.sendStatus(NOT_FOUND);
       } else {
         if (Configuration.configuration.getHostId().equals(id) ||
             Configuration.configuration.getHostSslId().equals(id)) {
           responder.sendStatus(NOT_FOUND);
         } else {
           TransferDAO transferDAO = null;
           try {
             transferDAO = DAO_FACTORY.getTransferDAO();
             final List<Filter> filters = new ArrayList<Filter>();
             Filter filter = new Filter(Columns.REQUESTED.name(), "=", id);
             filters.add(filter);
             long nb = transferDAO.count(filters);
             filters.clear();
             filter = new Filter(Columns.REQUESTER.name(), "=", id);
             filters.add(filter);
             nb += transferDAO.count(filters);
             if (nb > 0) {
               responder.sendStatus(NOT_FOUND);
             }
           } catch (final DAOConnectionException e) {
             throw new InternalServerErrorException(e);
           } finally {
             DAOFactory.closeDAO(transferDAO);
           }
         }
         hostDAO.delete(host);
         responder.sendStatus(NO_CONTENT);
       }
     } catch (final DAOConnectionException e) {
       throw new InternalServerErrorException(e);
     } catch (final DAONoDataException e) {
       responder.sendStatus(NOT_FOUND);
     } finally {
       DAOFactory.closeDAO(hostDAO);
     }
   }
 
   /**
    * 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
    * @param id the requested host's name
    */
   @OPTIONS
   @Consumes(WILDCARD)
   @RequiredRole(NOACCESS)
   public final void options(final HttpRequest request,
                             final HttpResponder responder,
                             @PathParam(URI_ID) final String id) {
     checkSanity(id);
     responder.sendStatus(OK, OPTIONS_HEADERS);
   }
 }