/* Copyright 2004-2005 the original author or authors.
 * 
 * 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.
 */ 
package org.codehaus.groovy.grails.orm.hibernate.validation;

import groovy.lang.GroovyObject;
import org.codehaus.groovy.grails.commons.GrailsDomainClass;
import org.codehaus.groovy.grails.metaclass.DomainClassMethods;
import org.codehaus.groovy.runtime.InvokerHelper;
import org.hibernate.SessionFactory;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.BeanWrapperImpl;
import org.springframework.orm.hibernate3.HibernateTemplate;
import org.springframework.validation.Errors;
import org.springframework.validation.Validator;

import java.util.Collection;
import java.util.Iterator;

/**
 * A validator that validates a domain class based on the applied constraints 
 * 
 * @author Graeme Rocher
 * @since 07-Nov-2005
 */
public class GrailsDomainClassValidator implements Validator {

    private Collection constrainedProperties;
    private Class targetClass;
    private HibernateTemplate template;
    private GrailsDomainClass domainClass;
    private SessionFactory sessionFactory;

    public boolean supports(Class clazz) {
        return this.targetClass.equals( clazz );
    }


    /**
     * @param domainClass The domainClass to set.
     */
    public void setDomainClass(GrailsDomainClass domainClass) {
        this.domainClass = domainClass;
        this.domainClass.setValidator(this);
        this.targetClass = this.domainClass.getClazz();
        this.constrainedProperties = domainClass.getConstrainedProperties().values();
    }

    /**
     * @param sessionFactory The sessionFactory to set.
     */
    public void setSessionFactory(SessionFactory sessionFactory) {
        this.sessionFactory = sessionFactory;
        this.template = new HibernateTemplate(this.sessionFactory);
    }

    public void validate(Object obj, Errors errors) {
        if(!domainClass.getClazz().isInstance(obj))
            throw new IllegalArgumentException("Argument ["+obj+"] is not an instance of ["+domainClass.getClazz()+"] which this validator is configured for");

        BeanWrapper bean = new BeanWrapperImpl(obj);

        for (Iterator i = constrainedProperties.iterator(); i.hasNext();) {
            ConstrainedPersistentProperty c = (ConstrainedPersistentProperty)i.next();
            c.setHibernateTemplate(this.template);
            c.validate(bean.getPropertyValue( c.getPropertyName() ),errors);
        }

         if(obj instanceof GroovyObject) {
            ((GroovyObject)obj).setProperty(DomainClassMethods.ERRORS_PROPERTY, errors);
         }
         else {
            InvokerHelper.setProperty(obj,DomainClassMethods.ERRORS_PROPERTY,errors);
         }
    }

    public void setHibernateTemplate(HibernateTemplate template) {
        this.template = template;
    }

}