////////////////////////////////////////////////////////////////////////////////
   // checkstyle: Checks Java source code for adherence to a set of rules.
   // Copyright (C) 2001-2019 the original author or authors.
   //
   // This library is free software; you can redistribute it and/or
   // modify it under the terms of the GNU Lesser General Public
   // License as published by the Free Software Foundation; either
   // version 2.1 of the License, or (at your option) any later version.
   //
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ////////////////////////////////////////////////////////////////////////////////
  
  package com.puppycrawl.tools.checkstyle.api;
  
  import java.beans.PropertyDescriptor;
  import java.lang.reflect.InvocationTargetException;
  import java.net.URI;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.List;
  import java.util.Locale;
  import java.util.StringTokenizer;
  import java.util.regex.Pattern;
  
  import org.apache.commons.beanutils.BeanUtilsBean;
  import org.apache.commons.beanutils.ConversionException;
  import org.apache.commons.beanutils.ConvertUtilsBean;
  import org.apache.commons.beanutils.Converter;
  import org.apache.commons.beanutils.PropertyUtils;
  import org.apache.commons.beanutils.PropertyUtilsBean;
  import org.apache.commons.beanutils.converters.ArrayConverter;
  import org.apache.commons.beanutils.converters.BooleanConverter;
  import org.apache.commons.beanutils.converters.ByteConverter;
  import org.apache.commons.beanutils.converters.CharacterConverter;
  import org.apache.commons.beanutils.converters.DoubleConverter;
  import org.apache.commons.beanutils.converters.FloatConverter;
  import org.apache.commons.beanutils.converters.IntegerConverter;
  import org.apache.commons.beanutils.converters.LongConverter;
  import org.apache.commons.beanutils.converters.ShortConverter;
  
  import com.puppycrawl.tools.checkstyle.checks.naming.AccessModifier;
  import com.puppycrawl.tools.checkstyle.utils.CommonUtil;
  
  /**
   * A Java Bean that implements the component lifecycle interfaces by
   * calling the bean's setters for all configuration attributes.
   */
  // -@cs[AbstractClassName] We can not brake compatibility with previous versions.
  public abstract class AutomaticBean
      implements Configurable, Contextualizable {
  
      /**
       * Enum to specify behaviour regarding ignored modules.
       */
      public enum OutputStreamOptions {
  
          /**
           * Close stream in the end.
           */
          CLOSE,
  
          /**
           * Do nothing in the end.
           */
          NONE,
  
      }
  
      /** Comma separator for StringTokenizer. */
      private static final String COMMA_SEPARATOR = ",";
  
      /** The configuration of this bean. */
      private Configuration configuration;
  
      /**
       * Provides a hook to finish the part of this component's setup that
       * was not handled by the bean introspection.
       * <p>
       * The default implementation does nothing.
       * </p>
       * @throws CheckstyleException if there is a configuration error.
       */
      protected abstract void finishLocalSetup() throws CheckstyleException;
  
      /**
       * Creates a BeanUtilsBean that is configured to use
       * type converters that throw a ConversionException
       * instead of using the default value when something
       * goes wrong.
       *
       * @return a configured BeanUtilsBean
       */
     private static BeanUtilsBean createBeanUtilsBean() {
         final ConvertUtilsBean cub = new ConvertUtilsBean();
 
         registerIntegralTypes(cub);
         registerCustomTypes(cub);
 
         return new BeanUtilsBean(cub, new PropertyUtilsBean());
     }
 
     /**
      * Register basic types of JDK like boolean, int, and String to use with BeanUtils. All these
      * types are found in the {@code java.lang} package.
      * @param cub
      *            Instance of {@link ConvertUtilsBean} to register types with.
      */
     private static void registerIntegralTypes(ConvertUtilsBean cub) {
         cub.register(new BooleanConverter(), Boolean.TYPE);
         cub.register(new BooleanConverter(), Boolean.class);
         cub.register(new ArrayConverter(
             boolean[].class, new BooleanConverter()), boolean[].class);
         cub.register(new ByteConverter(), Byte.TYPE);
         cub.register(new ByteConverter(), Byte.class);
         cub.register(new ArrayConverter(byte[].class, new ByteConverter()),
             byte[].class);
         cub.register(new CharacterConverter(), Character.TYPE);
         cub.register(new CharacterConverter(), Character.class);
         cub.register(new ArrayConverter(char[].class, new CharacterConverter()),
             char[].class);
         cub.register(new DoubleConverter(), Double.TYPE);
         cub.register(new DoubleConverter(), Double.class);
         cub.register(new ArrayConverter(double[].class, new DoubleConverter()),
             double[].class);
         cub.register(new FloatConverter(), Float.TYPE);
         cub.register(new FloatConverter(), Float.class);
         cub.register(new ArrayConverter(float[].class, new FloatConverter()),
             float[].class);
         cub.register(new IntegerConverter(), Integer.TYPE);
         cub.register(new IntegerConverter(), Integer.class);
         cub.register(new ArrayConverter(int[].class, new IntegerConverter()),
             int[].class);
         cub.register(new LongConverter(), Long.TYPE);
         cub.register(new LongConverter(), Long.class);
         cub.register(new ArrayConverter(long[].class, new LongConverter()),
             long[].class);
         cub.register(new ShortConverter(), Short.TYPE);
         cub.register(new ShortConverter(), Short.class);
         cub.register(new ArrayConverter(short[].class, new ShortConverter()),
             short[].class);
         cub.register(new RelaxedStringArrayConverter(), String[].class);
 
         // BigDecimal, BigInteger, Class, Date, String, Time, TimeStamp
         // do not use defaults in the default configuration of ConvertUtilsBean
     }
 
     /**
      * Register custom types of JDK like URI and Checkstyle specific classes to use with BeanUtils.
      * None of these types should be found in the {@code java.lang} package.
      * @param cub
      *            Instance of {@link ConvertUtilsBean} to register types with.
      */
     private static void registerCustomTypes(ConvertUtilsBean cub) {
         cub.register(new PatternConverter(), Pattern.class);
         cub.register(new SeverityLevelConverter(), SeverityLevel.class);
         cub.register(new ScopeConverter(), Scope.class);
         cub.register(new UriConverter(), URI.class);
         cub.register(new RelaxedAccessModifierArrayConverter(), AccessModifier[].class);
     }
 
     /**
      * Implements the Configurable interface using bean introspection.
      *
      * <p>Subclasses are allowed to add behaviour. After the bean
      * based setup has completed first the method
      * {@link #finishLocalSetup finishLocalSetup}
      * is called to allow completion of the bean's local setup,
      * after that the method {@link #setupChild setupChild}
      * is called for each {@link Configuration#getChildren child Configuration}
      * of {@code configuration}.
      *
      * @see Configurable
      */
     @Override
     public final void configure(Configuration config)
             throws CheckstyleException {
         configuration = config;
 
         final String[] attributes = config.getAttributeNames();
 
         for (final String key : attributes) {
             final String value = config.getAttribute(key);
 
             tryCopyProperty(key, value, true);
         }
 
         finishLocalSetup();
 
         final Configuration[] childConfigs = config.getChildren();
         for (final Configuration childConfig : childConfigs) {
             setupChild(childConfig);
         }
     }
 
     /**
      * Recheck property and try to copy it.
      * @param key key of value
      * @param value value
      * @param recheck whether to check for property existence before copy
      * @throws CheckstyleException when property defined incorrectly
      */
     private void tryCopyProperty(String key, Object value, boolean recheck)
             throws CheckstyleException {
         final BeanUtilsBean beanUtils = createBeanUtilsBean();
 
         try {
             if (recheck) {
                 // BeanUtilsBean.copyProperties silently ignores missing setters
                 // for key, so we have to go through great lengths here to
                 // figure out if the bean property really exists.
                 final PropertyDescriptor descriptor =
                         PropertyUtils.getPropertyDescriptor(this, key);
                 if (descriptor == null) {
                     final String message = String.format(Locale.ROOT, "Property '%s' "
                             + "does not exist, please check the documentation", key);
                     throw new CheckstyleException(message);
                 }
             }
             // finally we can set the bean property
             beanUtils.copyProperty(this, key, value);
         }
         catch (final InvocationTargetException | IllegalAccessException
                 | NoSuchMethodException ex) {
             // There is no way to catch IllegalAccessException | NoSuchMethodException
             // as we do PropertyUtils.getPropertyDescriptor before beanUtils.copyProperty
             // so we have to join these exceptions with InvocationTargetException
             // to satisfy UTs coverage
             final String message = String.format(Locale.ROOT,
                     "Cannot set property '%s' to '%s'", key, value);
             throw new CheckstyleException(message, ex);
         }
         catch (final IllegalArgumentException | ConversionException ex) {
             final String message = String.format(Locale.ROOT, "illegal value '%s' for property "
                     + "'%s'", value, key);
             throw new CheckstyleException(message, ex);
         }
     }
 
     /**
      * Implements the Contextualizable interface using bean introspection.
      * @see Contextualizable
      */
     @Override
     public final void contextualize(Context context)
             throws CheckstyleException {
         final Collection<String> attributes = context.getAttributeNames();
 
         for (final String key : attributes) {
             final Object value = context.get(key);
 
             tryCopyProperty(key, value, false);
         }
     }
 
     /**
      * Returns the configuration that was used to configure this component.
      * @return the configuration that was used to configure this component.
      */
     protected final Configuration getConfiguration() {
         return configuration;
     }
 
     /**
      * Called by configure() for every child of this component's Configuration.
      * <p>
      * The default implementation throws {@link CheckstyleException} if
      * {@code childConf} is {@code null} because it doesn't support children. It
      * must be overridden to validate and support children that are wanted.
      * </p>
      *
      * @param childConf a child of this component's Configuration
      * @throws CheckstyleException if there is a configuration error.
      * @see Configuration#getChildren
      */
     protected void setupChild(Configuration childConf)
             throws CheckstyleException {
         if (childConf != null) {
             throw new CheckstyleException(childConf.getName() + " is not allowed as a child in "
                     + configuration.getName() + ". Please review 'Parent Module' section "
                     + "for this Check in web documentation if Check is standard.");
         }
     }
 
     /** A converter that converts strings to patterns. */
     private static class PatternConverter implements Converter {
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             return CommonUtil.createPattern(value.toString());
         }
 
     }
 
     /** A converter that converts strings to severity level. */
     private static class SeverityLevelConverter implements Converter {
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             return SeverityLevel.getInstance(value.toString());
         }
 
     }
 
     /** A converter that converts strings to scope. */
     private static class ScopeConverter implements Converter {
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             return Scope.getInstance(value.toString());
         }
 
     }
 
     /** A converter that converts strings to uri. */
     private static class UriConverter implements Converter {
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             final String url = value.toString();
             URI result = null;
 
             if (!CommonUtil.isBlank(url)) {
                 try {
                     result = CommonUtil.getUriByFilename(url);
                 }
                 catch (CheckstyleException ex) {
                     throw new IllegalArgumentException(ex);
                 }
             }
 
             return result;
         }
 
     }
 
     /**
      * A converter that does not care whether the array elements contain String
      * characters like '*' or '_'. The normal ArrayConverter class has problems
      * with this characters.
      */
     private static class RelaxedStringArrayConverter implements Converter {
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             // Convert to a String and trim it for the tokenizer.
             final StringTokenizer tokenizer = new StringTokenizer(
                 value.toString().trim(), COMMA_SEPARATOR);
             final List<String> result = new ArrayList<>();
 
             while (tokenizer.hasMoreTokens()) {
                 final String token = tokenizer.nextToken();
                 result.add(token.trim());
             }
 
             return result.toArray(CommonUtil.EMPTY_STRING_ARRAY);
         }
 
     }
 
     /**
      * A converter that converts strings to {@link AccessModifier}.
      * This implementation does not care whether the array elements contain characters like '_'.
      * The normal {@link ArrayConverter} class has problems with this character.
      */
     private static class RelaxedAccessModifierArrayConverter implements Converter {
 
         /** Constant for optimization. */
         private static final AccessModifier[] EMPTY_MODIFIER_ARRAY = new AccessModifier[0];
 
         @SuppressWarnings({"unchecked", "rawtypes"})
         @Override
         public Object convert(Class type, Object value) {
             // Converts to a String and trims it for the tokenizer.
             final StringTokenizer tokenizer = new StringTokenizer(
                 value.toString().trim(), COMMA_SEPARATOR);
             final List<AccessModifier> result = new ArrayList<>();
 
             while (tokenizer.hasMoreTokens()) {
                 final String token = tokenizer.nextToken();
                 result.add(AccessModifier.getInstance(token.trim()));
             }
 
             return result.toArray(EMPTY_MODIFIER_ARRAY);
         }
 
     }
 
 }