/*
   Wotonomy: OpenStep design patterns for pure Java applications.
   Copyright (C) 2001 Michael Powers
   
   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, see http://www.gnu.org
  */
  
  package net.wotonomy.control;
  
  import net.wotonomy.foundation.NSKeyValueCoding;
  import net.wotonomy.foundation.NSMutableDictionary;
  import net.wotonomy.foundation.NSSelector;
  import net.wotonomy.foundation.internal.WotonomyException;
  
  /***
  * EOKeyValueQualifier performs a property-based
  * comparison against a specified value.  The comparison 
  * is specified in the form of a NSSelector.  The
  * selector is expected to take two arguments, the
  * property value on an object and the comparison value, 
  * and return a Boolean indicating whether the object
  * is qualified.  EOQualifier defines selectors that 
  * may be used in creating EOKeyValueQualifiers.
  *
  * @author michael@mpowers.net
  * @author yjcheung@intersectsoft.com
  * @author $Author: cgruber $
  * @version $Revision: 894 $
  */
  public class EOKeyValueQualifier extends EOQualifier
  	implements EOKeyValueArchiving, EOQualifierEvaluation
  {
      private String key;
      private NSSelector selector;
      private Object value;
  
      /***
      * Constructor specifying a property key, a selector,
      * and a value for comparison.  The selector may be
      * one of the constant selectors defined on EOQualifier.
      */
      public EOKeyValueQualifier(
          String aKey,
          NSSelector aSelector,
          Object aValue )
      {
          key = aKey;
          selector = aSelector;
          value = aValue;
      }
  
      /***
      * Returns the key for this qualifier.
      */
      public String key()
      {
          return key;
      }
  
      /***
      * Returns the selector for this qualifier.
      */
      public NSSelector selector()
      {
          return selector;
      }
  
      /***
      * Returns the value for this qualifier.
      */
      public Object value()
      {
          return value;
      }
  
      /***
      * Evaluates this qualifier for the specified object,
      * and returns whether the object is qualified.
      * selector() is invoked on the value for key() on the
      * specified object, with value() as the parameter.
      */
      public boolean evaluateWithObject( Object anObject )
      {
          try
          {
              Object value;
              if ( anObject instanceof EOKeyValueCoding )
              {
                 value = ((EOKeyValueCoding)anObject).valueForKey( key() );
             }
             else
             {
                 value = EOKeyValueCodingSupport.valueForKey( anObject, key() );
             }
             return ((Boolean)selector.invoke( value(), value)).booleanValue();
         }
         catch ( Exception exc )
         {
             throw new WotonomyException( exc );
         }
     }
 
     /***
     * Returns a string representation of this qualifier.
     */
     public String toString()
     {
         return "( " + key + " " + selector + " " + value + " )";
     }
 
 	public void encodeWithKeyValueArchiver(EOKeyValueArchiver arch) {
 		arch.encodeObject("EOKeyValueQualifier", "class");
 		arch.encodeObject(key, "key");
 		NSMutableDictionary d = new NSMutableDictionary(2);
 		if (value instanceof String)
 			d.setObjectForKey("NSString", "class");
 		else if (value instanceof java.math.BigDecimal)
 			d.setObjectForKey("NSDecimalNumber", "class");
 		else if (value instanceof Number)
 			d.setObjectForKey("NSNumber", "class");
 		else if (value instanceof NSKeyValueCoding.Null)
 			d.setObjectForKey("EONull", "class");
 		if (value != null && !(value instanceof NSKeyValueCoding.Null))
 			d.setObjectForKey(value.toString(), "value");
 		arch.encodeObject(d, "value");
 		String selname = null;
 		if (selector.equals(EOQualifier.QualifierOperatorCaseInsensitiveLike))
 			selname = "caseInsensitiveLike:";
 		else if (selector.equals(EOQualifier.QualifierOperatorContains))
 			selname = "contains:";
 		else if (selector.equals(EOQualifier.QualifierOperatorEqual))
 			selname = "isEqualTo:";
 		else if (selector.equals(EOQualifier.QualifierOperatorGreaterThan))
 			selname = "greaterThan:";
 		else if (selector.equals(EOQualifier.QualifierOperatorGreaterThanOrEqualTo))
 			selname = "greaterThanOrEqualTo:";
 		else if (selector.equals(EOQualifier.QualifierOperatorLessThan))
 			selname = "lessThan:";
 		else if (selector.equals(EOQualifier.QualifierOperatorLessThanOrEqualTo))
 			selname = "lessThanOrEqualTo:";
 		else if (selector.equals(EOQualifier.QualifierOperatorLike))
 			selname = "like:";
 		else if (selector.equals(EOQualifier.QualifierOperatorNotEqual))
 			selname = "isNotEqualTo:";
 		else
 			selname = selector.name() + ":";
 		arch.encodeObject(selname, "selectorName");
 	}
 
 	public static Object decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver arch) {
 		String k = (String)arch.decodeObjectForKey("key");
 		Object v = arch.decodeObjectForKey("value");
 		NSSelector sel = null;
 		String sname = (String)arch.decodeObjectForKey("selectorName");
 		if (sname.equals("isEqualTo:"))
 			sel = EOQualifier.QualifierOperatorEqual;
 		else if (sname.equals("isNotEqualTo:"))
 			sel = EOQualifier.QualifierOperatorNotEqual;
 		else if (sname.equals("caseInsensitiveLike:"))
 			sel = EOQualifier.QualifierOperatorCaseInsensitiveLike;
 		else if (sname.equals("contains:"))
 			sel = EOQualifier.QualifierOperatorContains;
 		else if (sname.equals("greaterThan:"))
 			sel = EOQualifier.QualifierOperatorGreaterThan;
 		else if (sname.equals("greaterThanOrEqualTo:"))
 			sel = EOQualifier.QualifierOperatorGreaterThanOrEqualTo;
 		else if (sname.equals("lessThan:"))
 			sel = EOQualifier.QualifierOperatorLessThan;
 		else if (sname.equals("lessThanOrEqualTo:"))
 			sel = EOQualifier.QualifierOperatorLessThanOrEqualTo;
 		else if (sname.equals("like:"))
 			sel = EOQualifier.QualifierOperatorLike;
 		EOKeyValueQualifier q = new EOKeyValueQualifier(k, sel, v);
 		return q;
 	}
 
 }
 
 /*
  * $Log$
  * Revision 1.2  2006/02/16 16:47:14  cgruber
  * Move some classes in to "internal" packages and re-work imports, etc.
  *
  * Also use UnsupportedOperationExceptions where appropriate, instead of WotonomyExceptions.
  *
  * Revision 1.1  2006/02/16 13:19:57  cgruber
  * Check in all sources in eclipse-friendly maven-enabled packages.
  *
  * Revision 1.10  2003/08/12 01:43:04  chochos
  * formally implement EOQualifierEvaluation
  *
  * Revision 1.9  2003/08/11 19:39:30  chochos
  * special conditions for NSKeyValueCoding.NullValue -> EONull
  *
  * Revision 1.8  2003/08/09 01:22:51  chochos
  * qualifiers implement EOKeyValueArchiving
  *
  * Revision 1.7  2003/08/06 23:07:52  chochos
  * general code cleanup (mostly, removing unused imports)
  *
  * Revision 1.6  2001/10/31 15:26:06  mpowers
  * Fixed typo.
  *
  * Revision 1.5  2001/10/31 15:25:14  mpowers
  * Cleanup of qualifiers.
  *
  * Revision 1.4  2001/10/30 22:57:28  mpowers
  * EOQualifier framework is now working.
  *
  * Revision 1.3  2001/09/13 15:25:56  mpowers
  * Started implementation of the EOQualifier framework.
  *
  * Revision 1.2  2001/03/29 03:29:49  mpowers
  * Now using KeyValueCoding and Support instead of Introspector.
  *
  * Revision 1.1  2001/02/27 03:33:04  mpowers
  * Initial draft of the key-value qualifier.
  *
  *
  */