package top.infra.jackson2;
   
   import com.fasterxml.jackson.databind.BeanDescription;
   import com.fasterxml.jackson.databind.DeserializationConfig;
   import com.fasterxml.jackson.databind.DeserializationContext;
   import com.fasterxml.jackson.databind.JavaType;
   import com.fasterxml.jackson.databind.JsonDeserializer;
   import com.fasterxml.jackson.databind.JsonMappingException;
   import com.fasterxml.jackson.databind.deser.DeserializerFactory;
  import com.fasterxml.jackson.databind.deser.Deserializers;
  import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
  import com.fasterxml.jackson.databind.type.TypeFactory;
  
  import org.apache.commons.lang3.tuple.Pair;
  
  import top.infra.jackson2.deser.PairDeserializer;
  
  /**
   * {@link com.fasterxml.jackson.databind.deser.BasicDeserializerFactory#findDefaultDeserializer(DeserializationContext, JavaType, BeanDescription)}
   * {@link com.fasterxml.jackson.databind.deser.BeanDeserializerFactory}
   * com.fasterxml.jackson.datatype.guava.GuavaDeserializers
   */
  public class CommonsLangDeserializers extends Deserializers.Base {
  
      private final DeserializerFactory deserializerFactory;
  
      public CommonsLangDeserializers(final DeserializerFactory deserializerFactory) {
          this.deserializerFactory = deserializerFactory;
      }
  
      @Override
      public JsonDeserializer<?> findBeanDeserializer(
          final JavaType type, final DeserializationConfig config, final BeanDescription beanDesc
      ) throws JsonMappingException {
          if (type.hasRawClass(Pair.class)) {
              JavaType kt = type.containedType(0);
              if (kt == null) {
                  kt = TypeFactory.unknownType();
              }
              TypeDeserializer kts = (TypeDeserializer) kt.getTypeHandler();
              if (kts == null) {
                  kts = this.deserializerFactory.findTypeDeserializer(config, kt);
              }
  
              JavaType vt = type.containedType(1);
              if (vt == null) {
                  vt = TypeFactory.unknownType();
              }
              TypeDeserializer vts = (TypeDeserializer) vt.getTypeHandler();
              if (vts == null) {
                  vts = this.deserializerFactory.findTypeDeserializer(config, vt);
              }
              JsonDeserializer<Object> valueDeser = vt.getValueHandler();
              JsonDeserializer<Object> keyDes = kt.getValueHandler();
              return new PairDeserializer(type, keyDes, kts, valueDeser, vts);
          }
          return null;
      }
  }