/*
 * 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.urlencoding;

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

import java.lang.annotation.*;
import java.nio.charset.*;
import java.util.*;
import java.util.concurrent.*;

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

/**
 * Parses URL-encoded text into POJO models.
 *
 * <h5 class='topic'>Media types</h5>
 * <p>
 * Handles <c>Content-Type</c> types:  <bc>application/x-www-form-urlencoded</bc>
 *
 * <h5 class='topic'>Description</h5>
 * <p>
 * Parses URL-Encoded text (e.g. <js>"foo=bar&amp;baz=bing"</js>) into POJOs.
 *
 * <p>
 * Expects parameter values to be in UON notation.
 *
 * <p>
 * This parser uses a state machine, which makes it very fast and efficient.
 *
 * <h5 class='section'>Notes:</h5><ul>
 *    <li class='note'>This class is thread safe and reusable.
 * </ul>
 *
 * <h5 class='section'>See Also:</h5><ul>
 *    <li class='link'><a class="doclink" href="https://juneau.apache.org/docs/topics/UrlEncodingBasics">URL-Encoding Basics</a>
 * </ul>
 */
public class UrlEncodingParser extends UonParser implements UrlEncodingMetaProvider {

   //-------------------------------------------------------------------------------------------------------------------
   // Static
   //-------------------------------------------------------------------------------------------------------------------

   /** Reusable instance of {@link UrlEncodingParser}. */
   public static final UrlEncodingParser DEFAULT = new UrlEncodingParser(create());

   /**
    * Creates a new builder for this object.
    *
    * @return A new builder.
    */
   public static Builder create() {
      return new Builder();
   }

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

   /**
    * Builder class.
    */
   public static class Builder extends UonParser.Builder {

      private static final Cache<HashKey,UrlEncodingParser> CACHE = Cache.of(HashKey.class, UrlEncodingParser.class).build();

      boolean expandedParams;

      /**
       * Constructor, default settings.
       */
      protected Builder() {
         decoding();
         consumes("application/x-www-form-urlencoded");
         expandedParams = env("UrlEncoding.expandedParams", false);
      }

      /**
       * Copy constructor.
       *
       * @param copyFrom The bean to copy from.
       */
      protected Builder(UrlEncodingParser copyFrom) {
         super(copyFrom);
         expandedParams = copyFrom.expandedParams;
      }

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

      @Override /* Context.Builder */
      public Builder copy() {
         return new Builder(this);
      }

      @Override /* Context.Builder */
      public UrlEncodingParser build() {
         return cache(CACHE).build(UrlEncodingParser.class);
      }

      @Override /* Context.Builder */
      public HashKey hashKey() {
         return HashKey.of(
            super.hashKey(),
            expandedParams
         );
      }

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

      /**
       * Serialize bean property collections/arrays as separate key/value pairs.
       *
       * <p>
       * This is the parser-side equivalent of the {@link UrlEncodingSerializer.Builder#expandedParams()} setting.
       *
       * <p>
       * If <jk>false</jk>, serializing the array <c>[1,2,3]</c> results in <c>?key=$a(1,2,3)</c>.
       * <br>If <jk>true</jk>, serializing the same array results in <c>?key=1&amp;key=2&amp;key=3</c>.
       *
       * <h5 class='section'>Example:</h5>
       * <p class='bjava'>
       *    <jk>public class</jk> MyBean {
       *       <jk>public</jk> String[] <jf>f1</jf>;
       *       <jk>public</jk> List&lt;String&gt; <jf>f2</jf>;
       *    }
       *
       *    UrlEncodingParser <jv>parser1</jv> = UrlEncodingParser.<jsf>DEFAULT</jsf>;
       *    UrlEncodingParser <jv>parser2</jv> = UrlEncodingParser.<jsm>create</jsm>().expandedParams().build();
       *
       *    MyBean <jv>myBean1</jv> = <jv>parser1</jv>.parse(<js>"f1=@(a,b)&amp;f2=@(c,d)"</js>, A.<jk>class</jk>);
       *
       *    MyBean <jv>myBean2</jv> = <jv>parser2</jv>.parse(<js>"f1=a&amp;f1=b&amp;f2=c&amp;f2=d"</js>, A.<jk>class</jk>);
       * </p>
       *
       * <p>
       * This option only applies to beans.
       *
       * <h5 class='section'>Notes:</h5><ul>
       *    <li class='note'>
       *       If parsing multi-part parameters, it's highly recommended to use Collections or Lists
       *       as bean property types instead of arrays since arrays have to be recreated from scratch every time a value
       *       is added to it.
       * </ul>
       *
       * @return This object.
       */
      public Builder expandedParams() {
         return expandedParams(true);
      }

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

   final boolean expandedParams;

   private final Map<ClassMeta<?>,UrlEncodingClassMeta> urlEncodingClassMetas = new ConcurrentHashMap<>();
   private final Map<BeanPropertyMeta,UrlEncodingBeanPropertyMeta> urlEncodingBeanPropertyMetas = new ConcurrentHashMap<>();

   /**
    * Constructor.
    *
    * @param builder The builder for this object.
    */
   public UrlEncodingParser(Builder builder) {
      super(builder);
      expandedParams = builder.expandedParams;
   }

   @Override /* Context */
   public Builder copy() {
      return new Builder(this);
   }

   @Override /* Context */
   public UrlEncodingParserSession.Builder createSession() {
      return UrlEncodingParserSession.create(this);
   }

   @Override /* Context */
   public UrlEncodingParserSession getSession() {
      return createSession().build();
   }

   //-----------------------------------------------------------------------------------------------------------------
   // Extended metadata
   //-----------------------------------------------------------------------------------------------------------------

   @Override /* UrlEncodingMetaProvider */
   public UrlEncodingClassMeta getUrlEncodingClassMeta(ClassMeta<?> cm) {
      UrlEncodingClassMeta m = urlEncodingClassMetas.get(cm);
      if (m == null) {
         m = new UrlEncodingClassMeta(cm, this);
         urlEncodingClassMetas.put(cm, m);
      }
      return m;
   }

   @Override /* UrlEncodingMetaProvider */
   public UrlEncodingBeanPropertyMeta getUrlEncodingBeanPropertyMeta(BeanPropertyMeta bpm) {
      if (bpm == null)
         return UrlEncodingBeanPropertyMeta.DEFAULT;
      UrlEncodingBeanPropertyMeta m = urlEncodingBeanPropertyMetas.get(bpm);
      if (m == null) {
         m = new UrlEncodingBeanPropertyMeta(bpm.getDelegateFor(), this);
         urlEncodingBeanPropertyMetas.put(bpm, m);
      }
      return m;
   }

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

   /**
    * Parser bean property collections/arrays as separate key/value pairs.
    *
    * @see Builder#expandedParams()
    * @return
    * <jk>false</jk> if serializing the array <c>[1,2,3]</c> results in <c>?key=$a(1,2,3)</c>.
    * <br><jk>true</jk> if serializing the same array results in <c>?key=1&amp;key=2&amp;key=3</c>.
    */
   protected final boolean isExpandedParams() {
      return expandedParams;
   }

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

   @Override /* Context */
   protected JsonMap properties() {
      return filteredMap("expandedParams", expandedParams);
   }
}