package com.lexicalscope.fluentreflection;

 import static java.util.Collections.unmodifiableList;

 import java.lang.reflect.Field;

 import java.util.ArrayList;

 import java.util.Collections;

 import java.util.List;

 import com.google.inject.TypeLiteral;

 final class ReflectedFieldsImpl<T> implements ReflectedFields<T> {

     private final ReflectedTypeFactory reflectedTypeFactory;

     private final ReflectedSuperclassesAndInterfaces<T> allTypes;

     private final TypeLiteral<T> typeLiteral;

     private List<FluentField> declaredFields;

     private List<FluentField> reflectedFields;

     ReflectedFieldsImpl(

             final ReflectedTypeFactory reflectedTypeFactory,

             final TypeLiteral<T> typeLiteral,

             final ReflectedSuperclassesAndInterfaces<T> allTypes) {

         this.reflectedTypeFactory = reflectedTypeFactory;

         this.typeLiteral = typeLiteral;

         this.allTypes = allTypes;

     }

     @Override public List<FluentField> fields() {

         if (reflectedFields == null) {

             final List<FluentField> result = new ArrayList<FluentField>();

             result.addAll(declaredFields());

             for (final FluentClass<?> klassToReflect : allTypes.superclassesAndInterfaces()) {

                 result.addAll(klassToReflect.declaredFields());

             }

             Collections.reverse(result);

             reflectedFields = unmodifiableList(result);

         }

         return reflectedFields;

     }

     private List<FluentField> getDeclaredFieldsOfClass(final TypeLiteral<?> typeLiteralToReflect) {

         final List<FluentField> result = new ArrayList<FluentField>();

         final Field[] declaredFields = typeLiteralToReflect.getRawType().getDeclaredFields();

         for (final Field method : declaredFields) {

             result.add(reflectedTypeFactory.field(typeLiteralToReflect, method));

         }

         return result;

     }

     @Override public List<FluentField> declaredFields() {

         if (declaredFields == null) {

             declaredFields = unmodifiableList(getDeclaredFieldsOfClass(typeLiteral));

         }

         return declaredFields;

     }

 }