/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.
   */
  package org.apache.syncope.ext.opensearch.client;
  
  import com.fasterxml.jackson.databind.JsonNode;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Optional;
  import java.util.Set;
  import java.util.stream.Collectors;
  import org.apache.commons.lang3.ArrayUtils;
  import org.apache.syncope.common.lib.types.AnyTypeKind;
  import org.apache.syncope.core.persistence.api.dao.AnyObjectDAO;
  import org.apache.syncope.core.persistence.api.dao.GroupDAO;
  import org.apache.syncope.core.persistence.api.dao.UserDAO;
  import org.apache.syncope.core.persistence.api.entity.Any;
  import org.apache.syncope.core.persistence.api.entity.AnyTypeClass;
  import org.apache.syncope.core.persistence.api.entity.PlainAttr;
  import org.apache.syncope.core.persistence.api.entity.PlainAttrValue;
  import org.apache.syncope.core.persistence.api.entity.Privilege;
  import org.apache.syncope.core.persistence.api.entity.Realm;
  import org.apache.syncope.core.persistence.api.entity.anyobject.AnyObject;
  import org.apache.syncope.core.persistence.api.entity.group.Group;
  import org.apache.syncope.core.persistence.api.entity.user.User;
  import org.springframework.transaction.annotation.Transactional;
  
  /**
   * Utility methods for usage with OpenSearch.
   */
  public class OpenSearchUtils {
  
      public static String getAnyIndex(final String domain, final AnyTypeKind kind) {
          return domain.toLowerCase() + '_' + kind.name().toLowerCase();
      }
  
      public static String getRealmIndex(final String domain) {
          return domain.toLowerCase() + "_realm";
      }
  
      public static String getAuditIndex(final String domain) {
          return domain.toLowerCase() + "_audit";
      }
  
      protected static final char[] ELASTICSEARCH_REGEX_CHARS = new char[] {
          '.', '?', '+', '*', '|', '{', '}', '[', ']', '(', ')', '"', '\\', '&' };
  
      public static String escapeForLikeRegex(final char c) {
          StringBuilder output = new StringBuilder();
  
          if (ArrayUtils.contains(ELASTICSEARCH_REGEX_CHARS, c)) {
              output.append('\\');
          }
  
          output.append(c);
  
          return output.toString();
      }
  
      protected final UserDAO userDAO;
  
      protected final GroupDAO groupDAO;
  
      protected final AnyObjectDAO anyObjectDAO;
  
      public OpenSearchUtils(
              final UserDAO userDAO,
              final GroupDAO groupDAO,
              final AnyObjectDAO anyObjectDAO) {
  
          this.userDAO = userDAO;
          this.groupDAO = groupDAO;
          this.anyObjectDAO = anyObjectDAO;
      }
  
      /**
       * Returns the document specialized with content from the provided any.
       *
       * @param any user, group or any object to index
      * @return document specialized with content from the provided any
      */
     @Transactional
     public Map<String, Object> document(final Any<?> any) {
         Collection<String> resources = any instanceof User
                 ? userDAO.findAllResourceKeys(any.getKey())
                 : any instanceof AnyObject
                         ? anyObjectDAO.findAllResourceKeys(any.getKey())
                         : groupDAO.findAllResourceKeys(any.getKey());
         Collection<String> dynRealms = any instanceof User
                 ? userDAO.findDynRealms(any.getKey())
                 : any instanceof AnyObject
                         ? anyObjectDAO.findDynRealms(any.getKey())
                         : groupDAO.findDynRealms(any.getKey());
 
         Map<String, Object> builder = new HashMap<>();
         builder.put("id", any.getKey());
         builder.put("realm", any.getRealm().getKey());
         builder.put("anyType", any.getType().getKey());
         builder.put("creationDate", any.getCreationDate());
         builder.put("creationContext", any.getCreationContext());
         builder.put("creator", any.getCreator());
         builder.put("lastChangeDate", any.getLastChangeDate());
         builder.put("lastModifier", any.getLastModifier());
         builder.put("lastChangeContext", any.getLastChangeContext());
         builder.put("status", any.getStatus());
         builder.put("auxClasses", any.getAuxClasses().stream().map(AnyTypeClass::getKey).collect(Collectors.toList()));
         builder.put("resources", resources);
         builder.put("dynRealms", dynRealms);
 
         if (any instanceof AnyObject) {
             AnyObject anyObject = ((AnyObject) any);
             builder.put("name", anyObject.getName());
 
             builder.put("memberships", anyObjectDAO.findAllGroupKeys(anyObject));
 
             List<String> relationships = new ArrayList<>();
             List<String> relationshipTypes = new ArrayList<>();
             anyObjectDAO.findAllRelationships(anyObject).forEach(relationship -> {
                 relationships.add(relationship.getRightEnd().getKey());
                 relationshipTypes.add(relationship.getType().getKey());
             });
             builder.put("relationships", relationships);
             builder.put("relationshipTypes", relationshipTypes);
 
             customizeDocument(builder, anyObject);
         } else if (any instanceof Group) {
             Group group = ((Group) any);
             builder.put("name", group.getName());
             Optional.ofNullable(group.getUserOwner()).ifPresent(uo -> builder.put("userOwner", uo.getKey()));
             Optional.ofNullable(group.getGroupOwner()).ifPresent(go -> builder.put("groupOwner", go.getKey()));
 
             Set<String> members = new HashSet<>();
             members.addAll(groupDAO.findUMemberships(group).stream().
                     map(membership -> membership.getLeftEnd().getKey()).collect(Collectors.toList()));
             members.addAll(groupDAO.findUDynMembers(group));
             members.addAll(groupDAO.findAMemberships(group).stream().
                     map(membership -> membership.getLeftEnd().getKey()).collect(Collectors.toList()));
             members.addAll(groupDAO.findADynMembers(group));
             builder.put("members", members);
 
             customizeDocument(builder, group);
         } else if (any instanceof User) {
             User user = ((User) any);
             builder.put("username", user.getUsername());
             builder.put("token", user.getToken());
             builder.put("tokenExpireTime", user.getTokenExpireTime());
             builder.put("changePwdDate", user.getChangePwdDate());
             builder.put("failedLogins", user.getFailedLogins());
             builder.put("lastLoginDate", user.getLastLoginDate());
             builder.put("suspended", user.isSuspended());
             builder.put("mustChangePassword", user.isMustChangePassword());
 
             List<String> roles = new ArrayList<>();
             Set<String> privileges = new HashSet<>();
             userDAO.findAllRoles(user).forEach(role -> {
                 roles.add(role.getKey());
                 privileges.addAll(role.getPrivileges().stream().map(Privilege::getKey).collect(Collectors.toSet()));
             });
             builder.put("roles", roles);
             builder.put("privileges", privileges);
 
             builder.put("memberships", userDAO.findAllGroupKeys(user));
 
             List<String> relationships = new ArrayList<>();
             Set<String> relationshipTypes = new HashSet<>();
             user.getRelationships().forEach(relationship -> {
                 relationships.add(relationship.getRightEnd().getKey());
                 relationshipTypes.add(relationship.getType().getKey());
             });
             builder.put("relationships", relationships);
             builder.put("relationshipTypes", relationshipTypes);
 
             customizeDocument(builder, user);
         }
 
         for (PlainAttr<?> plainAttr : any.getPlainAttrs()) {
             List<Object> values = plainAttr.getValues().stream().
                     map(PlainAttrValue::getValue).collect(Collectors.toList());
 
             Optional.ofNullable(plainAttr.getUniqueValue()).ifPresent(v -> values.add(v.getValue()));
 
             builder.put(plainAttr.getSchema().getKey(), values.size() == 1 ? values.get(0) : values);
         }
 
         return builder;
     }
 
     protected void customizeDocument(final Map<String, Object> builder, final AnyObject anyObject) {
     }
 
     protected void customizeDocument(final Map<String, Object> builder, final Group group) {
     }
 
     protected void customizeDocument(final Map<String, Object> builder, final User user) {
     }
 
     public Map<String, Object> document(final Realm realm) {
         Map<String, Object> builder = new HashMap<>();
         builder.put("id", realm.getKey());
         builder.put("name", realm.getName());
         builder.put("parent_id", realm.getParent() == null ? null : realm.getParent().getKey());
         builder.put("fullPath", realm.getFullPath());
 
         customizeDocument(builder, realm);
 
         return builder;
     }
 
     protected void customizeDocument(final Map<String, Object> builder, final Realm realm) {
     }
 
     public Map<String, Object> document(
             final long instant,
             final JsonNode message,
             final String domain) throws IOException {
 
         Map<String, Object> builder = new HashMap<>();
 
         builder.put("instant", instant);
         builder.put("message", message);
 
         customizeDocument(builder, instant, message, domain);
 
         return builder;
     }
 
     protected void customizeDocument(
             final Map<String, Object> builder,
             final long instant,
             final JsonNode message,
             final String domain)
             throws IOException {
     }
 }