/*
 * 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.juneau;


import static org.apache.juneau.collections.JsonMap.*;
import static org.apache.juneau.common.utils.Utils.*;

import java.lang.annotation.*;
import java.util.*;

import org.apache.juneau.collections.*;
import org.apache.juneau.internal.*;
import org.apache.juneau.utils.*;

/**
 * Parent class for all classes that traverse POJOs.
 *
 * <h5 class='topic'>Description</h5>
 * <p>
 * Base class that serves as the parent class for all serializers and other classes that traverse POJOs.
 *
 * <h5 class='section'>Notes:</h5><ul>
 *    <li class='note'>This class is thread safe and reusable.
 * </ul>
 *
 * <h5 class='section'>See Also:</h5><ul>

 * </ul>
 */
public abstract class BeanTraverseContext extends BeanContextable {

   //-------------------------------------------------------------------------------------------------------------------
   // Builder
   //-------------------------------------------------------------------------------------------------------------------

   /**
    * Builder class.
    */
   public abstract static class Builder extends BeanContextable.Builder {

      boolean detectRecursions, ignoreRecursions;
      int initialDepth, maxDepth;

      /**
       * Constructor, default settings.
       */
      protected Builder() {
         detectRecursions = env("BeanTraverseContext.detectRecursions", false);
         ignoreRecursions = env("BeanTraverseContext.ignoreRecursions", false);
         initialDepth = env("BeanTraverseContext.initialDepth", 0);
         maxDepth = env("BeanTraverseContext.maxDepth", 100);
      }

      /**
       * Copy constructor.
       *
       * @param copyFrom The bean to copy from.
       */
      protected Builder(BeanTraverseContext copyFrom) {
         super(copyFrom);
         detectRecursions = copyFrom.detectRecursions;
         ignoreRecursions = copyFrom.ignoreRecursions;
         initialDepth = copyFrom.initialDepth;
         maxDepth = copyFrom.maxDepth;
      }

      /**
       * Copy constructor.
       *
       * @param copyFrom The builder to copy from.
       */
      protected Builder(Builder copyFrom) {
         super(copyFrom);
         detectRecursions = copyFrom.detectRecursions;
         ignoreRecursions = copyFrom.ignoreRecursions;
         initialDepth = copyFrom.initialDepth;
         maxDepth = copyFrom.maxDepth;
      }

      @Override /* Context.Builder */
      public abstract Builder copy();

      @Override /* Context.Builder */
      public HashKey hashKey() {
         return HashKey.of(
            super.hashKey(),
            detectRecursions,
            ignoreRecursions,
            initialDepth,
            maxDepth
         );
      }

      //-----------------------------------------------------------------------------------------------------------------
      // Properties
      //-----------------------------------------------------------------------------------------------------------------

      /**
       * Automatically detect POJO recursions.
       *
       * <p>
       * When enabled, specifies that recursions should be checked for during traversal.
       *
       * <p>
       * Recursions can occur when traversing models that aren't true trees but rather contain loops.
       * <br>In general, unchecked recursions cause stack-overflow-errors.
       * <br>These show up as {@link BeanRecursionException BeanRecursionException} with the message <js>"Depth too deep.  Stack overflow occurred."</js>.
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>
       *       Checking for recursion can cause a small performance penalty.
       * </ul>
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that automatically checks for recursions.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .detectRecursions()
       *       .build();
       *
       *    <jc>// Create a POJO model with a recursive loop.</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> Object <jf>f</jf>;
       *    }
       *    MyBean <jv>bean</jv> = <jk>new</jk> MyBean();
       *    <jv>bean</jv>.<jf>f</jf> = <jv>bean</jv>;
       *
       *    <jc>// Throws a SerializeException and not a StackOverflowError</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.serialize(<jv>bean</jv>);
       * </p>
       *
       * @return This object.
       */
      public Builder detectRecursions() {
         return detectRecursions(true);
      }

      /**
       * Same as {@link #detectRecursions()} but allows you to explicitly specify the value.
       *
       * @param value The value for this setting.
       * @return This object.
       */
      public Builder detectRecursions(boolean value) {
         detectRecursions = value;
         return this;
      }

      /**
       * Ignore recursion errors.
       *
       * <p>
       * When enabled, when we encounter the same object when traversing a tree, we set the value to <jk>null</jk>.
       *
       * <p>
       * For example, if a model contains the links A-&gt;B-&gt;C-&gt;A, then the JSON generated will look like
       *    the following when this setting is <jk>true</jk>...
       *
       * <p class='bjson'>
       *    {A:{B:{C:<jk>null</jk>}}}
       * </p>
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>
       *       Checking for recursion can cause a small performance penalty.
       * </ul>
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer ignores recursions.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .ignoreRecursions()
       *       .build();
       *
       *    <jc>// Create a POJO model with a recursive loop.</jc>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> Object <jf>f</jf>;
       *    }
       *    MyBean <jv>bean</jv> = <jk>new</jk> MyBean();
       *    <jv>bean</jv>.<jf>f</jf> = <jv>bean</jv>;
       *
       *    <jc>// Produces "{f:null}"</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.serialize(<jv>bean</jv>);
       * </p>
       *
       * @return This object.
       */
      public Builder ignoreRecursions() {
         return ignoreRecursions(true);
      }

      /**
       * Same as {@link #ignoreRecursions()} but allows you to explicitly specify the value.
       *
       * @param value The value for this setting.
       * @return This object.
       */
      public Builder ignoreRecursions(boolean value) {
         ignoreRecursions = value;
         return this;
      }

      /**
       * Initial depth.
       *
       * <p>
       * The initial indentation level at the root.
       *
       * <p>
       * Useful when constructing document fragments that need to be indented at a certain level when whitespace is enabled.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer with whitespace enabled and an initial depth of 2.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .ws()
       *       .initialDepth(2)
       *       .build();
       *
       *    <jc>// Produces "\t\t{\n\t\t\t'foo':'bar'\n\t\t}\n"</jc>
       *    String <jv>json</jv> = <jv>serializer</jv>.serialize(<jk>new</jk> MyBean());
       * </p>
       *
       * @param value
       *    The new value for this setting.
       *    <br>The default is <c>0</c>.
       * @return This object.
       */
      public Builder initialDepth(int value) {
         initialDepth = value;
         return this;
      }

      /**
       * Max traversal depth.
       *
       * <p>
       * When enabled, abort traversal if specified depth is reached in the POJO tree.
       *
       * <p>
       * If this depth is exceeded, an exception is thrown.
       *
       * <p>
       * This prevents stack overflows from occurring when trying to traverse models with recursive references.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jc>// Create a serializer that throws an exception if the depth reaches greater than 20.</jc>
       *    WriterSerializer <jv>serializer</jv> = JsonSerializer
       *       .<jsm>create</jsm>()
       *       .maxDepth(20)
       *       .build();
       * </p>
       *
       * <h5 class='section'>See Also:</h5><ul>
       *    <li class='jm'>{@link Builder#maxDepth(int)}
       * </ul>
       *
       * @param value
       *    The new value for this setting.
       *    <br>The default is <c>100</c>.
       * @return This object.
       */
      public Builder maxDepth(int value) {
         maxDepth = value;
         return this;
      }
      @Override /* Overridden from Builder */
      public Builder annotations(Annotation...values) {
         super.annotations(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder apply(AnnotationWorkList work) {
         super.apply(work);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder applyAnnotations(Object...from) {
         super.applyAnnotations(from);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder applyAnnotations(Class<?>...from) {
         super.applyAnnotations(from);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder cache(Cache<HashKey,? extends org.apache.juneau.Context> value) {
         super.cache(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder debug() {
         super.debug();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder debug(boolean value) {
         super.debug(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder impl(Context value) {
         super.impl(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder type(Class<? extends org.apache.juneau.Context> value) {
         super.type(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanClassVisibility(Visibility value) {
         super.beanClassVisibility(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanConstructorVisibility(Visibility value) {
         super.beanConstructorVisibility(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanContext(BeanContext value) {
         super.beanContext(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanContext(BeanContext.Builder value) {
         super.beanContext(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanDictionary(java.lang.Class<?>...values) {
         super.beanDictionary(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanFieldVisibility(Visibility value) {
         super.beanFieldVisibility(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanInterceptor(Class<?> on, Class<? extends org.apache.juneau.swap.BeanInterceptor<?>> value) {
         super.beanInterceptor(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanMapPutReturnsOldValue() {
         super.beanMapPutReturnsOldValue();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanMethodVisibility(Visibility value) {
         super.beanMethodVisibility(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanProperties(Map<String,Object> values) {
         super.beanProperties(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanProperties(Class<?> beanClass, String properties) {
         super.beanProperties(beanClass, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanProperties(String beanClassName, String properties) {
         super.beanProperties(beanClassName, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesExcludes(Map<String,Object> values) {
         super.beanPropertiesExcludes(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesExcludes(Class<?> beanClass, String properties) {
         super.beanPropertiesExcludes(beanClass, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesExcludes(String beanClassName, String properties) {
         super.beanPropertiesExcludes(beanClassName, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesReadOnly(Map<String,Object> values) {
         super.beanPropertiesReadOnly(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesReadOnly(Class<?> beanClass, String properties) {
         super.beanPropertiesReadOnly(beanClass, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesReadOnly(String beanClassName, String properties) {
         super.beanPropertiesReadOnly(beanClassName, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesWriteOnly(Map<String,Object> values) {
         super.beanPropertiesWriteOnly(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesWriteOnly(Class<?> beanClass, String properties) {
         super.beanPropertiesWriteOnly(beanClass, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beanPropertiesWriteOnly(String beanClassName, String properties) {
         super.beanPropertiesWriteOnly(beanClassName, properties);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beansRequireDefaultConstructor() {
         super.beansRequireDefaultConstructor();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beansRequireSerializable() {
         super.beansRequireSerializable();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder beansRequireSettersForGetters() {
         super.beansRequireSettersForGetters();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder dictionaryOn(Class<?> on, java.lang.Class<?>...values) {
         super.dictionaryOn(on, values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder disableBeansRequireSomeProperties() {
         super.disableBeansRequireSomeProperties();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder disableIgnoreMissingSetters() {
         super.disableIgnoreMissingSetters();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder disableIgnoreTransientFields() {
         super.disableIgnoreTransientFields();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder disableIgnoreUnknownNullBeanProperties() {
         super.disableIgnoreUnknownNullBeanProperties();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder disableInterfaceProxies() {
         super.disableInterfaceProxies();
         return this;
      }

      @Override /* Overridden from Builder */
      public <T> Builder example(Class<T> pojoClass, T o) {
         super.example(pojoClass, o);
         return this;
      }

      @Override /* Overridden from Builder */
      public <T> Builder example(Class<T> pojoClass, String json) {
         super.example(pojoClass, json);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder findFluentSetters() {
         super.findFluentSetters();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder findFluentSetters(Class<?> on) {
         super.findFluentSetters(on);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder ignoreInvocationExceptionsOnGetters() {
         super.ignoreInvocationExceptionsOnGetters();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder ignoreInvocationExceptionsOnSetters() {
         super.ignoreInvocationExceptionsOnSetters();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder ignoreUnknownBeanProperties() {
         super.ignoreUnknownBeanProperties();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder ignoreUnknownEnumValues() {
         super.ignoreUnknownEnumValues();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder implClass(Class<?> interfaceClass, Class<?> implClass) {
         super.implClass(interfaceClass, implClass);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder implClasses(Map<Class<?>,Class<?>> values) {
         super.implClasses(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder interfaceClass(Class<?> on, Class<?> value) {
         super.interfaceClass(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder interfaces(java.lang.Class<?>...value) {
         super.interfaces(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder locale(Locale value) {
         super.locale(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder mediaType(MediaType value) {
         super.mediaType(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder notBeanClasses(java.lang.Class<?>...values) {
         super.notBeanClasses(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder notBeanPackages(String...values) {
         super.notBeanPackages(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder propertyNamer(Class<? extends org.apache.juneau.PropertyNamer> value) {
         super.propertyNamer(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder propertyNamer(Class<?> on, Class<? extends org.apache.juneau.PropertyNamer> value) {
         super.propertyNamer(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder sortProperties() {
         super.sortProperties();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder sortProperties(java.lang.Class<?>...on) {
         super.sortProperties(on);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder stopClass(Class<?> on, Class<?> value) {
         super.stopClass(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public <T, S> Builder swap(Class<T> normalClass, Class<S> swappedClass, ThrowingFunction<T,S> swapFunction) {
         super.swap(normalClass, swappedClass, swapFunction);
         return this;
      }

      @Override /* Overridden from Builder */
      public <T, S> Builder swap(Class<T> normalClass, Class<S> swappedClass, ThrowingFunction<T,S> swapFunction, ThrowingFunction<S,T> unswapFunction) {
         super.swap(normalClass, swappedClass, swapFunction, unswapFunction);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder swaps(Object...values) {
         super.swaps(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder swaps(Class<?>...values) {
         super.swaps(values);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder timeZone(TimeZone value) {
         super.timeZone(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder typeName(Class<?> on, String value) {
         super.typeName(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder typePropertyName(String value) {
         super.typePropertyName(value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder typePropertyName(Class<?> on, String value) {
         super.typePropertyName(on, value);
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder useEnumNames() {
         super.useEnumNames();
         return this;
      }

      @Override /* Overridden from Builder */
      public Builder useJavaBeanIntrospector() {
         super.useJavaBeanIntrospector();
         return this;
      }
   }

   //-------------------------------------------------------------------------------------------------------------------
   // Instance
   //-------------------------------------------------------------------------------------------------------------------

   final int initialDepth, maxDepth;
   final boolean
      detectRecursions,
      ignoreRecursions;

   private final boolean actualDetectRecursions;

   /**
    * Constructor
    *
    * @param builder The builder for this object.
    */
   protected BeanTraverseContext(Builder builder) {
      super(builder);

      maxDepth = builder.maxDepth;
      initialDepth = builder.initialDepth;
      ignoreRecursions = builder.ignoreRecursions;
      detectRecursions = builder.detectRecursions;

      actualDetectRecursions = detectRecursions || ignoreRecursions || super.isDebug();
   }

   @Override /* Context */
   public abstract Builder copy();

   //-----------------------------------------------------------------------------------------------------------------
   // Properties
   //-----------------------------------------------------------------------------------------------------------------

   /**
    * Automatically detect POJO recursions.
    *
    * @see Builder#detectRecursions()
    * @return
    *    <jk>true</jk> if recursions should be checked for during traversal.
    */
   public final boolean isDetectRecursions() {
      return actualDetectRecursions;
   }

   /**
    * Ignore recursion errors.
    *
    * @see Builder#ignoreRecursions()
    * @return
    *    <jk>true</jk> if when we encounter the same object when traversing a tree, we set the value to <jk>null</jk>.
    *    <br>Otherwise, an exception is thrown with the message <js>"Recursion occurred, stack=..."</js>.
    */
   public final boolean isIgnoreRecursions() {
      return ignoreRecursions;
   }

   /**
    * Initial depth.
    *
    * @see Builder#initialDepth(int)
    * @return
    *    The initial indentation level at the root.
    */
   public final int getInitialDepth() {
      return initialDepth;
   }

   /**
    * Max traversal depth.
    *
    * @see Builder#maxDepth(int)
    * @return
    *    The depth at which traversal is aborted if depth is reached in the POJO tree.
    * <br>If this depth is exceeded, an exception is thrown.
    */
   public final int getMaxDepth() {
      return maxDepth;
   }

   //-----------------------------------------------------------------------------------------------------------------
   // Other methods
   //-----------------------------------------------------------------------------------------------------------------

   @Override /* Context */
   protected JsonMap properties() {
      return filteredMap("detectRecursions", detectRecursions, "maxDepth", maxDepth, "ignoreRecursions", ignoreRecursions, "initialDepth", initialDepth);
   }
}