/*
    * Copyright 2011 the original author or authors.
    *
    * Licensed 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.openehealth.ipf.commons.ihe.xds.core.requests.query;
  
  import javax.xml.bind.annotation.XmlAccessType;
  import javax.xml.bind.annotation.XmlAccessorType;
  import javax.xml.bind.annotation.XmlTransient;
  import javax.xml.bind.annotation.XmlType;
  import javax.xml.bind.annotation.adapters.XmlAdapter;
  import java.util.List;
  import java.util.stream.Collectors;
  
  /**
   * A JAXB {@link XmlAdapter} that helps serialize generic lists of lists. This sort of thing is used by the
   * IPF {@link QueryList} class but is not handled naturally by JAXB. It takes a little effort here to get a
   * reasonable serialization.
   *
   * @param <T> The type of object contained in the inner list
   */
  @XmlTransient
  public class ListOfListAdapter<T> extends XmlAdapter<ListOfListAdapter.ListOfListWrapper<T>, List<List<T>>> {
      @Override
      public List<List<T>> unmarshal(ListOfListWrapper<T> v) throws Exception {
          return v.getInnerList().stream()
                  .map(ListWrapper::getValue)
                  .collect(Collectors.toList());
      }
  
      @Override
      public ListOfListWrapper<T> marshal(List<List<T>> v) throws Exception {
          List<ListWrapper<T>> outerList = v.stream()
                  .map(ListWrapper::new)
                  .collect(Collectors.toList());
          return new ListOfListWrapper<>(outerList);
      }
  
      @XmlType(name = "ListOfListWrapper", namespace = "http://www.openehealth.org/ipf/xds")
      @XmlAccessorType(XmlAccessType.FIELD)
      public static class ListOfListWrapper<T> {
          private List<ListWrapper<T>> innerList;
  
          // Required for JAXB
          @SuppressWarnings({"UnusedDeclaration"})
          protected ListOfListWrapper() {
          }
  
          public ListOfListWrapper(List<ListWrapper<T>> list) {
              this.innerList = list;
          }
  
          public List<ListWrapper<T>> getInnerList() {
              return innerList;
          }
      }
  
      @XmlType(name = "ListWrapper", namespace = "http://www.openehealth.org/ipf/xds")
      @XmlAccessorType(XmlAccessType.FIELD)
      public static class ListWrapper<T> {
          private List<T> value;
  
          // Required for JAXB
          @SuppressWarnings({"UnusedDeclaration"})
          protected ListWrapper() {
          }
  
          public ListWrapper(List<T> list) {
              this.value = list;
          }
  
          public List<T> getValue() {
              return value;
          }
      }
  }