/*
    * 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.common.lib.jackson;
  
  import com.fasterxml.jackson.core.JsonGenerator;
  import com.fasterxml.jackson.core.JsonProcessingException;
  import com.fasterxml.jackson.databind.SerializationFeature;
  import com.fasterxml.jackson.databind.json.JsonMapper;
  import java.io.File;
  import java.io.IOException;
  import java.io.OutputStream;
  import java.io.Writer;
  import java.util.Map;
  
  /**
   * Jackson ObjectMapper that unwraps singleton map values and enable default
   * typing for handling abstract types serialization.
   */
  public class SyncopeJsonMapper extends JsonMapper {
  
      private static final long serialVersionUID = -317191546835195103L;
  
      public SyncopeJsonMapper() {
          super();
  
          findAndRegisterModules();
  
          configure(SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
      }
  
      /**
       * Unwraps the given value if it implements the Map interface and contains only a single entry, otherwise the
       * value is returned unmodified.
       *
       * @param value the potential Map to unwrap
       * @return the unwrapped map or the original value
       */
      protected Object unwrapMap(final Object value) {
          if (value instanceof Map) {
              Map<?, ?> map = (Map<?, ?>) value;
              if (map.size() == 1) {
                  return map.values().iterator().next();
              }
          }
  
          return value;
      }
  
      @Override
      public void writeValue(final JsonGenerator jgen, final Object value) throws IOException {
          super.writeValue(jgen, unwrapMap(value));
      }
  
      @Override
      public void writeValue(final File resultFile, final Object value) throws IOException {
          super.writeValue(resultFile, unwrapMap(value));
      }
  
      @Override
      public void writeValue(final OutputStream out, final Object value) throws IOException {
          super.writeValue(out, unwrapMap(value));
      }
  
      @Override
      public void writeValue(final Writer writer, final Object value) throws IOException {
          super.writeValue(writer, unwrapMap(value));
      }
  
      @Override
      public byte[] writeValueAsBytes(final Object value) throws JsonProcessingException {
          return super.writeValueAsBytes(unwrapMap(value));
      }
  
      @Override
      public String writeValueAsString(final Object value) throws JsonProcessingException {
          return super.writeValueAsString(unwrapMap(value));
      }
  }