# WopiSettings.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.util;

    import org.silverpeas.core.util.URLUtil;
    import org.silverpeas.kernel.SilverpeasRuntimeException;
    import org.silverpeas.kernel.bundle.ResourceLocator;
    import org.silverpeas.kernel.bundle.SettingBundle;
    import org.silverpeas.kernel.util.Pair;
    import org.silverpeas.kernel.util.StringUtil;

    import javax.ws.rs.core.UriBuilder;
    import java.net.URI;
    import java.util.Optional;

    import static java.util.Optional.ofNullable;
    import static org.silverpeas.kernel.util.StringUtil.isDefined;

    /**
     * @author silveryocha
     */
    public class WopiSettings {

      private static final String SETTINGS_PATH = "org.silverpeas.wbe.wopi.wopiSettings";

      private WopiSettings() {
      }

      /**
       * Indicates if WOPI is enabled.
       * @return true if enabled, false otherwise.
       */
      public static boolean isEnabled() {
        return getSettings().getBoolean("wopi.enabled", false);
      }

      /**
       * Indicates if WOPI lock capability is enabled.
       * @return true if enabled, false otherwise.
       */
      public static boolean isLockCapabilityEnabled() {
        return isEnabled() && getSettings().getBoolean("wopi.lock.enabled", false);
      }

      /**
       * Gets the elements for timestamp verification feature on put file operation.
       * @return an optional pair containing on left the timestamp request header name and on right
       * the JSON response in case of conflict.
       */
      public static Optional<Pair<String, String>> getTimestampVerificationElements() {
        return Optional.of(isEnabled())
            .filter(b -> b)
            .map(b -> Pair.of(
                getSettings().getString("wopi.putFile.timestamp.field", ""),
                getSettings().getString("wopi.putFile.timestamp.conflict.json.response", "{}")))
            .filter(p -> isDefined(p.getFirst()));
      }

      /**
       * Gets the field name to check in order to detected an editor close.
       * @return an optional string.
       */
      public static Optional<String> getExitFieldNameDetection() {
        return Optional.of(isEnabled())
            .filter(b -> b)
            .map(b -> getSettings().getString("wopi.client.exit.field", ""))
            .filter(StringUtil::isDefined);
      }

      /**
       * Gets the base URL of the WOPI host.
       * @return an string.
       */
      public static String getWopiHostServiceBaseUrl() {
        return getSettings().getString("wopi.host.service.baseUrl",
            URLUtil.getAbsoluteApplicationURL() + "/services/wbe/wopi/files");
      }

      /**
       * Gets the base URL of the WOPI client if any.
       * @return an optional string.
       */
      public static Optional<String> getWopiClientBaseUrl() {
        return Optional.of(WopiSettings.isEnabled())
            .filter(b -> b)
            .map(b -> getSettings().getString("wopi.client.baseUrl", null))
            .filter(StringUtil::isDefined);
      }

      /**
       * Gets the WOPI client discovery URL.
       * @return a string.
       */
      public static String getWopiClientDiscoveryUrl() {
        return getWopiClientBaseUrl()
            .map(UriBuilder::fromUri)
            .map(b -> b.path(getSettings().getString("wopi.client.discovery.path")))
            .map(UriBuilder::build)
            .map(URI::toString)
            .orElseThrow(() -> new SilverpeasRuntimeException(
                "wopi is not enabled or wopi.client.baseUrl or wopi.client.discovery.path are not " +
                    "defined"));
      }

      /**
       * Gets the time to live in hours of the discovery cache.
       * <p>
       *   12 hours by default.
       * </p>
       * @return a number of hours as long.
       */
      public static long getWopiClientDiscoveryTimeToLive() {
        return getSettings().getLong("wopi.client.discovery.timeToLive", 12);
      }

      /**
       * Gets the WOPI client administration URL.
       * @return a string.
       */
      public static String getWopiClientAdministrationUrl() {
        return getWopiClientBaseUrl()
            .map(UriBuilder::fromUri)
            .map(b -> b.path(getSettings().getString("wopi.client.admin.path")))
            .map(UriBuilder::build)
            .map(URI::toString)
            .orElseThrow(() -> new SilverpeasRuntimeException(
                "wopi is not enabled or wopi.client.baseUrl or wopi.client.admin.path are not " +
                    "defined"));
      }

      /**
       * Gets the UI defaults.
       * @return a {@link Pair} containing the hidden parameter name on left and the UI defaults
       * string on right.
       */
      public static Optional<Pair<String, String>> getUIDefaults() {
        return ofNullable(getSettings().getString("wopi.ui.defaults.param.name", null))
            .filter(StringUtil::isDefined)
            .flatMap(n -> ofNullable(getSettings().getString("wopi.ui.defaults", null))
                .filter(StringUtil::isDefined)
                .map(d -> Pair.of(n, d)));
      }

      private static SettingBundle getSettings() {
        return ResourceLocator.getSettingBundle(SETTINGS_PATH);
      }
    }