/*
 * $Id: ValidatorForm.java 54929 2004-10-16 16:38:42Z germuska $ 
 *
 * Copyright 2000-2004 The Apache Software Foundation.
 * 
 * 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.apache.struts.validator;

import java.io.Serializable;
import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.validator.Validator;
import org.apache.commons.validator.ValidatorException;
import org.apache.commons.validator.ValidatorResults;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;

/**
 * <p>This class extends <strong>ActionForm</strong> and provides
 * basic field validation based on an XML file.  The key passed into the
 * validator is the action element's 'name' attribute from the
 * struts-config.xml which should match the form element's name attribute
 * in the validation.xml.</p>
 *
 * <ul><li>See <code>ValidatorPlugin</code> definition in struts-config.xml
 * for validation rules.</li></ul>
 *
 * @version $Rev: 54929 $ $Date: 2004-10-16 17:38:42 +0100 (Sat, 16 Oct 2004) $
 * @see org.apache.struts.action.ActionForm
 * @since Struts 1.1
 */
public class ValidatorForm extends ActionForm implements Serializable {

    /**
     * Commons Logging instance.
     */
    private static Log log = LogFactory.getLog(ValidatorForm.class);

    /**
     * The results returned from the validation performed
     * by the <code>Validator</code>.
     */
    protected ValidatorResults validatorResults = null;

    /**
     * Used to indicate the current page of a multi-page form.
     */
    protected int page = 0;

    /**
     * Gets page.
     * @return page number
     */
    public int getPage() {
        return page;
    }

    /**
     * Sets page.
     * @param page page number
     */
    public void setPage(int page) {
        this.page = page;
    }

    /**
     * Validate the properties that have been set from this HTTP request,
     * and return an <code>ActionErrors</code> object that encapsulates any
     * validation errors that have been found.  If no errors are found, return
     * <code>null</code> or an <code>ActionErrors</code> object with no
     * recorded error messages.
     *
     * @param mapping The mapping used to select this instance
     * @param request The servlet request we are processing
     * @return  <code>ActionErrors</code> object that encapsulates any  validation errors

     */
    public ActionErrors validate(ActionMapping mapping,
                                 HttpServletRequest request) {

        ServletContext application = getServlet().getServletContext();
        ActionErrors errors = new ActionErrors();

        String validationKey = getValidationKey(mapping, request);

        Validator validator = Resources.initValidator(validationKey,
                             this,
                             application, request,
                             errors, page);

        try {
            validatorResults = validator.validate();
        } catch (ValidatorException e) {
            log.error(e.getMessage(), e);
        }

        return errors;
    }

    /**
     * Returns the Validation key.
     *
     * @param mapping The mapping used to select this instance
     * @param request The servlet request we are processing
     * @return validation key - the form element's name in this case
     */
    public String getValidationKey(ActionMapping mapping,
                                   HttpServletRequest request) {

        return mapping.getAttribute();
    }

    /**
     * Reset all properties to their default values.
     *
     * @param mapping The mapping used to select this instance
     * @param request The servlet request we are processing
     */
    public void reset(ActionMapping mapping, HttpServletRequest request) {
        super.reset(mapping, request);
        page = 0;
        validatorResults = null;
    }

    /**
     * Get results of the validation performed by the
     * <code>Validator</code>.
     * @return results of the validation
     */
    public ValidatorResults getValidatorResults() {
        return validatorResults;
    }

    /**
     * Set results of the validation performed by the
     * <code>Validator</code>.
     * @param validatorResults results of validation
     */
    public void setValidatorResults(ValidatorResults validatorResults) {
        this.validatorResults = validatorResults;
    }

    /**
     * Returns a <code>Map</code> of values returned
     * from any validation that returns a value other than
     * <code>null</code> or <code>Boolean</code> with the
     * key the full property path of the field.
     * @return  <code>Map</code> of non-null values
     */
    public Map getResultValueMap() {
        return (validatorResults != null ? validatorResults.getResultValueMap() : null);
    }
}