/*******************************************************************************
 * Copyright (c) 2010 Robert "Unlogic" Olofsson (unlogic@unlogic.se).
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Lesser Public License v3
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/lgpl-3.0-standalone.html
 ******************************************************************************/
package se.unlogic.standardutils.string;

import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Set;


public class BeanTagSource<T> implements TagSource{

   private final T bean;
   private final Set<String> tagSet;
   private final HashMap<String,Method> tagMethodMap;
   private final HashMap<String,Field> tagFieldMap;

   public BeanTagSource(final T bean, final HashMap<String, Method> tagMethodMap, final HashMap<String, Field> tagFieldMap, final Set<String> tagSet) {

      super();
      this.bean = bean;
      this.tagMethodMap = tagMethodMap;
      this.tagFieldMap = tagFieldMap;
      this.tagSet = tagSet;
   }

   public String getTagValue(String tag) {

      Field field = this.tagFieldMap.get(tag);

      if(field != null){

         try {
            Object value = field.get(bean);

            if(value != null){

               return value.toString();
            }

            return null;

         } catch (IllegalArgumentException e) {

            throw new RuntimeException(e);

         } catch (IllegalAccessException e) {

            throw new RuntimeException(e);
         }
      }

      Method method = tagMethodMap.get(tag);

      if(method != null){

         try {
            Object value = method.invoke(bean);

            if(value != null){

               return value.toString();
            }

            return null;

         } catch (IllegalArgumentException e) {

            throw new RuntimeException(e);

         } catch (IllegalAccessException e) {

            throw new RuntimeException(e);

         } catch (InvocationTargetException e) {

            throw new RuntimeException(e);
         }
      }

      return null;
   }

   public Set<String> getTags() {

      return this.tagSet;
   }
}
