/*

  * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH

  *

  * Licensed 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 de.smartics.properties.spi.core.metadata;

 import java.lang.reflect.Method;

 import java.util.HashMap;

 import java.util.Locale;

 import java.util.Map;

 import javax.annotation.concurrent.ThreadSafe;

 import org.apache.commons.lang.StringUtils;

 import org.apache.commons.lang.builder.ToStringBuilder;

 import de.smartics.projectdoc.annotations.Document;

 import de.smartics.properties.api.core.domain.DocumentName;

 import de.smartics.properties.api.core.domain.PropertiesContext;

 import de.smartics.properties.api.core.domain.PropertyDescriptor;

 import de.smartics.properties.api.core.domain.PropertyKey;

 import de.smartics.properties.api.core.domain.PropertyProjectdoc;

 import de.smartics.properties.api.core.domain.PropertySetProjectdoc;

 import de.smartics.properties.spi.core.metadata.projectdoc.AnnotationHelper;

 import de.smartics.properties.spi.core.metadata.projectdoc.ProjectdocAnnotationCollector;

 import de.smartics.properties.spi.core.metadata.projectdoc.ProjectdocAnnotationCollector.Defaults;

 import de.smartics.properties.spi.core.metadata.projectdoc.PropertyProjectdocParser;

 import de.smartics.properties.spi.core.metadata.projectdoc.PropertySetProjectdocParser;

 import de.smartics.properties.spi.core.util.SerializableMethod;

 import de.smartics.util.lang.Arg;

 /**

  * Allows to lazy load annotation information.

  */

 @ThreadSafe

 public final class MetaInfDocumentMetaDataProxy implements

     DocumentMetaDataProxy

 {

   // ********************************* Fields *********************************

   // --- constants ------------------------------------------------------------

   /**

    * The class version identifier.

    */

   private static final long serialVersionUID = 1L;

   // --- members --------------------------------------------------------------

   /**

    * The name of the document that identifies the document uniquely within the

    * context of the project. It is used to select the projectdoc document in the

    * <code>META-INF</code> folder.

    *

    * @serial

    */

   private final DocumentName documentName;

   /**

    * The properties context to fetch information from the <code>META-INF</code>

    * folder. May be <code>null</code>.

    *

    * @serial

    */

   private final PropertiesContext context;

   /**

    * The method to use to fetch annotations in case the context is not to be

    * used.

    *

    * @serial

    */

   private final SerializableMethod propertyMethod;

   /**

    * The cached property comments.

    *

    * @serial

    */

   private final Map<Locale, PropertyProjectdoc> metaData =

       new HashMap<Locale, PropertyProjectdoc>();

   /**

    * The cached property set comments.

    *

    * @serial

    */

   private final Map<Locale, PropertySetProjectdoc> propertySetMetaData =

       new HashMap<Locale, PropertySetProjectdoc>();

   // ****************************** Initializer *******************************

   // ****************************** Constructors ******************************

   /**

    * Default constructor.

    *

    * @param key the property key to the method.

    * @param context the properties context to fetch information from the

    *          <code>META-INF</code> folder. May be <code>null</code>.

    * @param propertyMethod the method to use to fetch annotations in case the

    *          context is not to be used.

    * @throws NullPointerException if {@code key} or {@code propertyMethod} is

    *           {@code null}.

    */

   public MetaInfDocumentMetaDataProxy(final PropertyKey key,

       final PropertiesContext context, final Method propertyMethod)

     throws NullPointerException

   {

     Arg.checkNotNull("key", key);

     this.context = context;

     this.propertyMethod =

         new SerializableMethod(Arg.checkNotNull("propertyMethod",

             propertyMethod));

     this.documentName = calculateDocumentName(key, propertyMethod);

   }

   // ****************************** Inner Classes *****************************

   // ********************************* Methods ********************************

   // --- init -----------------------------------------------------------------

   // --- get&set --------------------------------------------------------------

   private static DocumentName calculateDocumentName(final PropertyKey key,

       final Method propertyMethod)

   {

     final Document annotation = propertyMethod.getAnnotation(Document.class);

     String name = propertyMethod.getName();

     if (annotation != null)

     {

       final String value = annotation.name();

       if (value != null)

       {

         final AnnotationHelper helper = new AnnotationHelper();

         final String annName = helper.normalizeString(value);

         if (StringUtils.isNotBlank(annName)) // NOPMD

         {

           name = annName;

         }

       }

     }

     final String setName = key.getPropertySet();

     final String fqn = setName != null ? setName + '.' + name : name;

     final DocumentName documentName = new DocumentName(fqn);

     return documentName;

   }

   /**

    * Returns the name of the document that identifies the document uniquely

    * within the context of the project. It is used to select the projectdoc

    * document in the <code>META-INF</code> folder.

    *

    * @return the name of the document that identifies the document uniquely

    *         within the context of the project.

    */

   @Override

   public DocumentName getDocumentName()

   {

     return documentName;

   }

   // --- business -------------------------------------------------------------

   @Override

   public PropertySetProjectdoc getProjectdocPropertySet(

       final PropertyDescriptor descriptor, final Locale locale)

   {

     synchronized (propertySetMetaData)

     {

       PropertySetProjectdoc metaData = propertySetMetaData.get(locale);

       if (metaData == null)

       {

         final Method propertyMethod = this.propertyMethod.getMethod();

         ensureMethodPresent(propertyMethod);

         if (context != null)

         {

           final Defaults defaults =

               PropertyMetaDataDefaults.propertySet(propertyMethod);

           final PropertySetProjectdocParser parser =

               new PropertySetProjectdocParser(context, defaults);

           metaData = parser.parse(descriptor, locale);

         }

         if (metaData == null)

         {

           metaData = new PropertySetProjectdoc();

         }

         this.propertySetMetaData.put(locale, metaData);

       }

       return metaData;

     }

   }

   @Override

   public PropertyProjectdoc getProjectdocProperty(

       final PropertyDescriptor descriptor, final Locale locale)

   {

     synchronized (metaData)

     {

       PropertyProjectdoc metaData = this.metaData.get(locale);

       if (metaData == null)

       {

         final Method propertyMethod = this.propertyMethod.getMethod();

         ensureMethodPresent(propertyMethod);

         if (context != null)

         {

           final Defaults defaults =

               new PropertyMetaDataDefaults(propertyMethod);

           final PropertyProjectdocParser parser =

               new PropertyProjectdocParser(context, defaults);

           metaData = parser.parse(descriptor, locale);

         }

         if (metaData == null)

         {

           final Class<?> declaringType = propertyMethod.getDeclaringClass();

           final Defaults parentDefaults =

               new PropertyMetaDataDefaults(declaringType, propertyMethod);

           final Defaults defaults =

               new PropertyMetaDataDefaults(propertyMethod);

           final ProjectdocAnnotationCollector collector =

               new ProjectdocAnnotationCollector(declaringType, parentDefaults,

                   defaults);

           metaData =

               PropertyProjectdoc.upgrade(collector

                   .createMetaDataFromAnnotations(propertyMethod));

         }

         if (metaData != null)

         {

           this.metaData.put(locale, metaData);

         }

       }

       return metaData;

     }

   }

   private void ensureMethodPresent(final Method propertyMethod)

   {

     if (propertyMethod == null)

     {

       throw new IllegalStateException(

           "Cannot find documentation for method value 'null'.");

     }

   }

   // --- object basics --------------------------------------------------------

   /**

    * Returns the string representation of the object.

    *

    * @return the string representation of the object.

    */

   @Override

   public String toString()

   {

     return ToStringBuilder.reflectionToString(this);

   }

 }