/**

  * Copyright 2005-2013 Dozer Project

  *

  * 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.dozer.util;

 import org.dozer.fieldmap.HintContainer;

 import org.dozer.propertydescriptor.DozerPropertyDescriptor;

 import org.dozer.propertydescriptor.PropertyDescriptorFactory;

 import java.util.Collection;

 import java.util.StringTokenizer;

 /**

  * @author Dmitry Spikhalskiy

  */

 public class DeepHierarchyUtils {

   // Copy-paste from GetterSetterPropertyDescriptor

   public static Object getDeepFieldValue(Object srcObj, String fieldName, boolean isIndexed, int index, HintContainer srcDeepIndexHintContainer) {

     // follow deep field hierarchy. If any values are null along the way, then return null

     Object parentObj = srcObj;

     Object hierarchyValue = parentObj;

     DozerPropertyDescriptor[] hierarchy = getDeepFieldHierarchy(srcObj.getClass(), fieldName, srcDeepIndexHintContainer);

     for (DozerPropertyDescriptor hierarchyElement : hierarchy) {

       hierarchyValue = hierarchyElement.getPropertyValue(parentObj);

       parentObj = hierarchyValue;

       if (hierarchyValue == null) {

         break;

       }

     }

     if (isIndexed) {

       hierarchyValue = MappingUtils.getIndexedValue(hierarchyValue, index);

     }

     return hierarchyValue;

   }

   public static Class<?> getDeepFieldType(Class<?> clazz, String fieldName, HintContainer deepIndexHintContainer) {

     // follow deep field hierarchy. If any values are null along the way, then return null

     DozerPropertyDescriptor[] hierarchy = getDeepFieldHierarchy(clazz, fieldName, deepIndexHintContainer);

     return hierarchy[hierarchy.length - 1].getPropertyType();

   }

   public static Class<?> getDeepGenericType(Class<?> clazz, String fieldName, HintContainer deepIndexHintContainer) {

     // follow deep field hierarchy. If any values are null along the way, then return null

     DozerPropertyDescriptor[] hierarchy = getDeepFieldHierarchy(clazz, fieldName, deepIndexHintContainer);

     return hierarchy[hierarchy.length - 1].genericType();

   }

   private static DozerPropertyDescriptor[] getDeepFieldHierarchy(Class<?> parentClass, String field, HintContainer deepIndexHintContainer) {

     if (!MappingUtils.isDeepMapping(field)) {

       MappingUtils.throwMappingException("Field does not contain deep field delimiter");

     }

     StringTokenizer toks = new StringTokenizer(field, DozerConstants.DEEP_FIELD_DELIMITER);

     Class<?> latestClass = parentClass;

     DozerPropertyDescriptor[] hierarchy = new DozerPropertyDescriptor[toks.countTokens()];

     int index = 0;

     int hintIndex = 0;

     while (toks.hasMoreTokens()) {

       String aFieldName = toks.nextToken();

       String theFieldName = aFieldName;

       int collectionIndex = -1;

       if (aFieldName.contains("[")) {

         theFieldName = aFieldName.substring(0, aFieldName.indexOf("["));

         collectionIndex = Integer.parseInt(aFieldName.substring(aFieldName.indexOf("[") + 1, aFieldName.indexOf("]")));

       }

       DozerPropertyDescriptor propDescriptor = PropertyDescriptorFactory.getPropertyDescriptor(latestClass, null, null, null, null, false,

               collectionIndex > -1, collectionIndex, theFieldName, null,

               false, null, null, null, null); //we can pass null as a hint container - if genericType return null - we will use hintContainer in the underlying if

       if (propDescriptor == null) {

         MappingUtils.throwMappingException("Exception occurred determining deep field hierarchy for Class --> "

                 + parentClass.getName() + ", Field --> " + field + ".  Unable to determine property descriptor for Class --> "

                 + latestClass.getName() + ", Field Name: " + aFieldName);

       }

       latestClass = propDescriptor.getPropertyType();

       if (toks.hasMoreTokens()) {

         if (latestClass.isArray()) {

           latestClass = latestClass.getComponentType();

         } else if (Collection.class.isAssignableFrom(latestClass)) {

           Class<?> genericType = propDescriptor.genericType();

           if (genericType == null && deepIndexHintContainer == null) {

             MappingUtils

                     .throwMappingException("Hint(s) or Generics not specified.  Hint(s) or Generics must be specified for deep mapping with indexed field(s). Exception occurred determining deep field hierarchy for Class --> "

                             + parentClass.getName()

                             + ", Field --> "

                             + field

                             + ".  Unable to determine property descriptor for Class --> "

                             + latestClass.getName() + ", Field Name: " + aFieldName);

           }

           if (genericType != null) {

             latestClass = genericType;

           } else {

             latestClass = deepIndexHintContainer.getHint(hintIndex);

             hintIndex += 1;

           }

         }

       }

       hierarchy[index++] = propDescriptor;

     }

     return hierarchy;

   }

 }