# WopiRequestDispatcher.java

    /*
     * Copyright (C) 2000 - 2021 Silverpeas
     *
     * This program is free software: you can redistribute it and/or modify
     * it under the terms of the GNU Affero General Public License as
     * published by the Free Software Foundation, either version 3 of the
     * License, or (at your option) any later version.
     *
     * As a special exception to the terms and conditions of version 3.0 of
     * the GPL, you may redistribute this Program in connection with Free/Libre
     * Open Source Software ("FLOSS") applications as described in Silverpeas's
     * FLOSS exception.  You should have received a copy of the text describing
     * the FLOSS exception, and it is also available here:
     * "https://www.silverpeas.org/legal/floss_exception.html"
     *
     * This program 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 Affero General Public License for more details.
     *
     * You should have received a copy of the GNU Affero General Public License
     * along with this program.  If not, see <http://www.gnu.org/licenses/>.
     */

    package org.silverpeas.wbe.wopi;

    import org.silverpeas.core.annotation.Service;
    import org.silverpeas.core.wbe.WbeEdition;
    import org.silverpeas.core.wbe.WbeFile;
    import org.silverpeas.core.wbe.WbeUser;
    import org.silverpeas.core.webapi.wbe.WbeFileEdition;

    import javax.servlet.http.HttpServletRequest;
    import javax.ws.rs.core.UriBuilder;
    import java.util.Optional;

    import static java.text.MessageFormat.format;
    import static java.util.Optional.of;
    import static javax.ws.rs.core.UriBuilder.fromUri;
    import static org.silverpeas.core.wbe.WbeLogger.logger;
    import static org.silverpeas.core.webapi.wbe.WbeFileEdition.ACCESS_TOKEN_PARAM;
    import static org.silverpeas.wbe.wopi.util.WopiSettings.getWopiHostServiceBaseUrl;

    /**
     * @author silveryocha
     */
    @Service
    public class WopiRequestDispatcher implements WbeFileEdition.ClientRequestDispatcher {

      private static final String WOPI_SRC_PARAM = "WOPISrc";

      @Override
      public boolean canHandle(final WbeEdition edition) {
        return edition instanceof WopiEdition;
      }

      @Override
      public Optional<String> dispatch(final HttpServletRequest request, final WbeEdition edition) {
        final WopiEdition wopiEdition = (WopiEdition) edition;
        final WbeUser editionUser = wopiEdition.getUser();
        final WbeFile editionFile = wopiEdition.getFile();
        final String fileId = editionFile.id();
        final UriBuilder hostUriBuilder = fromUri(getWopiHostServiceBaseUrl()).path(fileId);
        final UriBuilder uriBuilder = fromUri(wopiEdition.getClientBaseUrl())
            .queryParam(WOPI_SRC_PARAM, hostUriBuilder.build())
            .queryParam(ACCESS_TOKEN_PARAM, editionUser.getAccessToken());
        final String clientUrl = uriBuilder.build().toString();
        logger().debug(() -> format(
            "from {0} initializing WOPI edition for {1} and for user {2} with WOPI client URL {3}",
            editionUser.getSilverpeasSessionId(), editionFile, editionUser, clientUrl));
        return of(clientUrl).map(u -> {
          request.setAttribute("WopiClientUrl", u);
          request.setAttribute("WopiUser", editionUser);
          request.setAttribute("WopiFile", editionFile);
          return "/wbe/wopi/editor.jsp";
        });
      }
    }