/*==========================================================================*\
 |  $Id: AdvancedQueryCriterion.java,v 1.1 2010/05/11 14:51:59 aallowat Exp $
 |*-------------------------------------------------------------------------*|
 |  Copyright (C) 2006-2008 Virginia Tech
 |
 |  This file is part of Web-CAT.
 |
 |  Web-CAT is free software; you can redistribute it and/or modify
 |  it under the terms of the GNU Affero General Public License as published
 |  by the Free Software Foundation; either version 3 of the License, or
 |  (at your option) any later version.
 |
 |  Web-CAT 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 General Public License for more details.
 |
 |  You should have received a copy of the GNU Affero General Public License
 |  along with Web-CAT; if not, see <http://www.gnu.org/licenses/>.
\*==========================================================================*/

package org.webcat.core.objectquery;

import com.webobjects.foundation.NSKeyValueCoding;

//-------------------------------------------------------------------------
/**
 * Represents the criterion used in an {@link AdvancedQueryComparison}, where
 * a KVC path can be compared against a literal value, or another KVC
 * value.
 *
 * @author aallowat
 * @version $Id: AdvancedQueryCriterion.java,v 1.1 2010/05/11 14:51:59 aallowat Exp $
 */
public class AdvancedQueryCriterion implements NSKeyValueCoding
{
    //~ Constructor ...........................................................

    // ----------------------------------------------------------
    public AdvancedQueryComparison comparison()
    {
        return comparison;
    }


    //~ Public Constants ......................................................

    public static final int COMPARAND_LITERAL = 0;
    public static final int COMPARAND_KEYPATH = 1;


    //~ Public Methods ........................................................

    // ----------------------------------------------------------
    public String keyPath()
    {
        return keyPath;
    }


    // ----------------------------------------------------------
    public void setKeyPath(String kp)
    {
        keyPath = kp;
    }


    // ----------------------------------------------------------
    public Class<?> castType()
    {
        return castType;
    }


    // ----------------------------------------------------------
    public void setCastType(Class<?> ct)
    {
        castType = ct;
    }


    // ----------------------------------------------------------
    public void setComparison(AdvancedQueryComparison c)
    {
        comparison = c;
    }


    // ----------------------------------------------------------
    public int comparandType()
    {
        return comparandType;
    }


    // ----------------------------------------------------------
    public void setComparandType(int ct)
    {
        comparandType = ct;
    }


    // ----------------------------------------------------------
    public Object value()
    {
        if (value == NSKeyValueCoding.NullValue)
        {
            return null;
        }
        else
        {
            return value;
        }
    }


    // ----------------------------------------------------------
    public void setValue(Object v)
    {
        value = v;
    }


    // ----------------------------------------------------------
    public void appendHumanReadableDescription(StringBuffer buffer)
    {
        buffer.append(keyPath);
        // TODO finish
    }


    // ----------------------------------------------------------
    public String toString()
    {
        StringBuffer buffer = new StringBuffer();

        buffer.append("AdvancedQueryCriterion = { ");
        buffer.append("keyPath = " + keyPath);
        buffer.append(", comparison = " + comparison);
        buffer.append(", comparandType = ");

        if (comparandType == COMPARAND_LITERAL)
        {
            buffer.append("LITERAL");
        }
        else if(comparandType == COMPARAND_KEYPATH)
        {
            buffer.append("KEYPATH");
        }

        buffer.append(", value = " + value);
        buffer.append(" }");

        return buffer.toString();
    }


    // ----------------------------------------------------------
    public void takeValueForKey(Object value, String key)
    {
        NSKeyValueCoding.DefaultImplementation.takeValueForKey(
            this, value, key);
    }


    // ----------------------------------------------------------
    public Object valueForKey(String key)
    {
        return NSKeyValueCoding.DefaultImplementation.valueForKey(this, key);
    }


    //~ Instance/static variables .............................................

    /*
     * The type of the right hand side of the comparison (keypath or literal).
     * The term "comparand" is derived from the gerundive of the Latin
     * "comparare" in the sense of "that which is to be compared"; this is
     * analogous to such mathematical terms as "addend", "minuend", and
     * "subtrahend".
     */
    private int comparandType;

    private String keyPath;
    private Class<?> castType;
    private AdvancedQueryComparison comparison;
    private Object value;
}