/**
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided
 * that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright
 *    statements and notices.  Redistributions must also contain a
 *    copy of this document.
 *
 * 2. Redistributions in binary form must reproduce the
 *    above copyright notice, this list of conditions and the
 *    following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. The name "Exolab" must not be used to endorse or promote
 *    products derived from this Software without prior written
 *    permission of Intalio, Inc.  For written permission,
 *    please contact info@exolab.org.
 *
 * 4. Products derived from this Software may not be called "Exolab"
 *    nor may "Exolab" appear in their names without prior written
 *    permission of Intalio, Inc. Exolab is a registered
 *    trademark of Intalio, Inc.
 *
 * 5. Due credit should be given to the Exolab Project
 *    (http://www.exolab.org/).
 *
 * THIS SOFTWARE IS PROVIDED BY INTALIO, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
 * INTALIO, INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 1999 (C) Intalio, Inc. All Rights Reserved.
 *
 * $Id: SimpleTypeValidator.java,v 1.2 2004/10/01 13:25:13 snyder Exp $
 */

package org.exolab.castor.xml;

import java.lang.reflect.Array;
import java.util.Enumeration;
import java.util.Vector;


/**
 * A class for defining simple rules used for validating a content model
 * @author <a href="mailto:kvisco@intalio.com">Keith Visco</a>
 * @version $Revision: 1.2 $ $Date: 2004/10/01 13:25:13 $
**/
public class SimpleTypeValidator implements TypeValidator {
    
    /**
     * The minimum occurance that the node must appear
    **/
    private int minOccurs = 0;
    
    /**
     * The maximum occurance that the node must appear
    **/
    private int maxOccurs = -1;
    
    /**
     * The type validate to delegate validation to
    **/
    private TypeValidator validator = null;
    
    /**
     * Creates a default SimpleTypeValidator
    **/
    public SimpleTypeValidator() {
        super();
    } //-- SimpleTypeValidator
    
    /**
     * Creates a SimpleTypeValidator using the given TypeValidator for
     * delegating validation
    **/
    public SimpleTypeValidator(TypeValidator validator) {
        super();
        this.validator = validator;
    } //-- SimpleTypeValidator

    /**
     * Sets the maximum occurance that the described field may occur
     * @param maxOccurs the maximum occurance that the descibed field 
     * may occur.
    **/
    public void setMaxOccurs(int maxOccurs) {
        this.maxOccurs = maxOccurs;
    } //-- setMaxOccurs

    /**
     * Sets the minimum occurance that the described field may occur
     * @param minOccurs the minimum occurance that the descibed field 
     * may occur.
    **/
    public void setMinOccurs(int minOccurs) {
        this.minOccurs = minOccurs;
    } //-- setMinOccurs
    
    /**
     * Sets the TypeValidator to delegate validation to
     * @param validator the TypeValidator to delegate validation to
    **/
    public void setValidator(TypeValidator validator) {
        this.validator = validator;
    } //-- setValidator
    
    /**
     * Validates the given Object
     *
     * @param object the Object to validate
     * @param context the ValidationContext
     */
    public void validate(Object object, ValidationContext context)
        throws ValidationException 
    {
        
        boolean required = (minOccurs > 0);
        
        if ((object == null) && (required)) {
            String err = "This field is required and cannot be null.";
            throw new ValidationException(err);
        }
        
        if (object != null) {
            Class type = object.getClass();
            
            int size = 1;
            boolean byteArray = false;
            if (type.isArray()) {
                byteArray = (type.getComponentType() == Byte.TYPE);
                if (!byteArray) size = Array.getLength(object);
            }
            
            //-- check minimum
            if (size < minOccurs) {
                String err = "A minimum of " + minOccurs
                    + " instance(s) of this field are required.";
                throw new ValidationException(err);
            }
            
            //-- check maximum
            if ((maxOccurs >= 0) && (size > maxOccurs)) {
                String err = "A maximum of " + maxOccurs + 
                    " instance(s) of this field are required.";
                throw new ValidationException(err);
            }
            
            if (validator == null) return;
            
            //-- check type
            if (isPrimitive(type) || (type == String.class)) {
                validator.validate(object, context);
            }
            else if (byteArray) { 
                //-- do nothing for now
            }
            else if (type.isArray()) {
                size = Array.getLength(object);
                for (int i = 0; i < size; i++) {
                    validator.validate(Array.get(object, i), context);
                }
            }
            else if (object instanceof java.util.Enumeration) {
                Enumeration enumeration = (Enumeration)object;
                while (enumeration.hasMoreElements())
                    validator.validate(enumeration.nextElement(), context);
            }
            else if (object instanceof java.util.Vector) {
                Vector vector = (Vector)object;
                for (int i = 0; i < vector.size(); i++) {
                    validator.validate(vector.elementAt(i), context);
                }
            }
            else validator.validate(object, context);
        }
            
    } //-- validate
    
    //-------------------/
    //- Private Methods -/
    //-------------------/
    
    /**
     * Returns true if the given class type should be
     * treated as a primitive. Wrapper objects such
     * as java.lang.Integer, and java.lang.Float, will
     * be treated as primitives.
     * @param type the Class to check
     * @return true if the given class should be treated
     * as a primitive type.
    **/
    private boolean isPrimitive(Class type) {
        
        if (type.isPrimitive()) return true;
        
        if ((type == Boolean.class)   ||
            (type == Byte.class)      ||
            (type == Character.class) ||
            (type == Double.class)    ||
            (type == Float.class)     ||
            (type == Integer.class)   ||
            (type == Long.class)      ||
            (type == Short.class)) 
            return true;
            
       return false;
       
    } //-- isPrimitive
    
} //-- SimpleTypeValidator