/*
    * Copyright 2003 - 2013 The eFaps Team
    *
    * 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.
   *
   * Revision:        $Rev$
   * Last Changed:    $Date$
   * Last Changed By: $Author$
   */
  
  
  package org.efaps.db.search.compare;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.efaps.admin.datamodel.Classification;
  import org.efaps.admin.datamodel.Type;
  import org.efaps.db.AbstractObjectQuery;
  import org.efaps.db.search.AbstractQPart;
  import org.efaps.db.search.QAttribute;
  import org.efaps.db.search.value.AbstractQValue;
  import org.efaps.db.search.value.QClassValue;
  import org.efaps.db.wrapper.SQLPart;
  import org.efaps.db.wrapper.SQLSelect;
  import org.efaps.util.EFapsException;
  
  /**
   * Compare that a classification id is equal to the given value.
   *
   * @author The eFaps Team
   * @version $Id$
   */
  public class QClassEqual
      extends AbstractQAttrCompare
  {
  
     /**
      * The values the given attribute must be equal to.
      */
      private final List<QClassValue> values = new ArrayList<QClassValue>();
  
      /**
       * Constructor setting attribute and value.
       * @param _values    values as criteria
       */
      public QClassEqual(final QClassValue... _values)
      {
          super(new QAttribute("ID"), null);
          for (final QClassValue value : _values) {
              this.values.add(value);
          }
      }
  
      /**
       * Get the first value from the value list.
       *
       * @return null if list is empty else first value
       */
      @Override
      public AbstractQValue getValue()
      {
          return this.values.isEmpty() ? null : this.values.get(0);
      }
  
      /**
       * Getter method for the instance variable {@link #values}.
       *
       * @return value of instance variable {@link #values}
       */
      public List<QClassValue> getValues()
      {
          return this.values;
      }
  
      /**
       * Add a value to be included in the equal.
       * @param _value value to be include
       * @return this
       */
      public AbstractQPart addValue(final QClassValue _value)
      {
          this.values.add(_value);
          return this;
      }
  
      /**
       * {@inheritDoc}
       */
     @Override
     public QClassEqual prepare(final AbstractObjectQuery<?> _query,
                                  final AbstractQPart _part)
         throws EFapsException
     {
         getAttribute().prepare(_query, this);
         for (final QClassValue value : this.values) {
             value.prepare(_query, this);
         }
         return this;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public QClassEqual appendSQL(final SQLSelect _sql)
         throws EFapsException
     {
         getAttribute().appendSQL(_sql);
         final Classification clazz = this.values.get(0).getClassification();
         final Type relType = clazz.getClassifyRelationType();
         _sql.addPart(SQLPart.IN).addPart(SQLPart.PARENTHESIS_OPEN).addPart(SQLPart.SELECT)
             .addColumnPart(null, relType.getAttribute(clazz.getRelLinkAttributeName()).getSqlColNames().get(0))
             .addPart(SQLPart.FROM)
             .addTablePart(relType.getMainTable().getSqlTable(), null)
             .addPart(SQLPart.WHERE)
             .addColumnPart(null, relType.getAttribute(clazz.getRelTypeAttributeName()).getSqlColNames().get(0));
 
         if (this.values.size() > 1) {
             _sql.addPart(SQLPart.IN).addPart(SQLPart.PARENTHESIS_OPEN);
             boolean first = true;
             for (final QClassValue value : this.values) {
                 if (first) {
                     first = false;
                 } else {
                     _sql.addPart(SQLPart.COMMA);
                 }
                 value.appendSQL(_sql);
             }
             _sql.addPart(SQLPart.PARENTHESIS_CLOSE);
         } else {
             _sql.addPart(SQLPart.EQUAL);
             getValue().appendSQL(_sql);
         }
         _sql.addPart(SQLPart.PARENTHESIS_CLOSE);
         return this;
     }
 }