/**
    * This file Copyright (c) 2013-2015 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.dam.asset.model;
  
  import java.util.Collection;
  import java.util.Map;
  import java.util.Set;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Map based <b>read only</b> representation of an Asset. This class is for
   * instance used in template scripts to allow notations like <code>asset.propName</code>. <br>
   * It read a property with name (key) and return his value. If not found an
   * empty string is returned. <br>
   * <b>Binary data will not be part of the AssetMap</b>.<br>
   * 
   * <pre>
   * Try to access the property name from the Asset object.
   *      key = fileName, returned value is Asset.getFileName().
   * If not found try to access the value based on the Metadata map.
   *      key = contributor, returned value is metadataMap.get('contributor').
   * If not part of the MetadataMap, return an empty String.
   * </pre>
   * 
   * By convenience <br>
   * We also support asset.metadata.dc or asset.metadata.mgnl call for metadata
   * property access.
   */
  public class AssetMap implements Map<String, Object> {
  
      private final static Logger log = LoggerFactory.getLogger(AssetMap.class);
  
      private final Map<String, Object> assetMap;
  
      public AssetMap(Map<String, Object> assetMap) {
          this.assetMap = assetMap;
      }
  
      @Override
      public boolean containsKey(Object key) {
          // Sanity check.
          String strKey = convertKey(key);
          if (!isValidKey(strKey)) {
              return false;
          }
          return assetMap.containsKey(strKey);
      }
  
      @Override
      public Object get(Object key) {
          Object value = StringUtils.EMPTY;
          if (!containsKey(key)) {
              return value;
          }
          String strKey = convertKey(key);
  
          return assetMap.get(strKey);
      }
  
      @Override
      public Set<String> keySet() {
          return assetMap.keySet();
      }
  
      @Override
     public int size() {
         return keySet().size();
     }
 
     private boolean isValidKey(String strKey) {
         return !StringUtils.isBlank(strKey);
     }
 
     private String convertKey(Object key) {
         if (key == null) {
             return null;
         }
         try {
             return (String) key;
         } catch (ClassCastException e) {
             log.debug("Invalid key. Expected String, but got {}.", key.getClass().getName());
         }
         return null;
     }
 
 
     @Override
     public Collection<Object> values() {
         throw new UnsupportedOperationException("Value collections are not supported");
     }
 
     @Override
     public Set<java.util.Map.Entry<String, Object>> entrySet() {
         throw new UnsupportedOperationException("Entry collections are not supported");
     }
 
     @Override
     public boolean containsValue(Object arg0) {
         throw new UnsupportedOperationException("Value checks are not supported");
     }
 
     @Override
     public boolean isEmpty() {
         // can never be empty because an asset has at least a Name.
         return false;
     }
 
     @Override
     public void clear() {
         // ignore, read only.
     }
 
     @Override
     public Object put(String arg0, Object arg1) {
         // ignore, read only.
         return null;
     }
 
     @Override
     public void putAll(Map<? extends String, ? extends Object> arg0) {
         // ignore, read only.
     }
 
     @Override
     public Object remove(Object arg0) {
         // ignore, read only.
         return null;
     }
 
 }