/* ======================================================================
   Parts Copyright 2006 University of Leeds, Oxford University, University of the Highlands and Islands.

   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.bodington.spring.easyedit;

import java.util.regex.Pattern;

import org.bodington.spring.UrlGenerator;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;

public class CreateValidator implements Validator
{

    public void validate(Object obj, Errors errors)
    {
        CreateCommand createCommand = (CreateCommand)obj;
        ValidationUtils.rejectIfEmptyOrWhitespace(errors, "title", "empty", "Title cannot be empty");
        
        if (createCommand.getUrl() == null) {
            String url = UrlGenerator.fromTitle(createCommand.getTitle());
            createCommand.setUrl(url);
            ValidationUtils.rejectIfEmpty(errors, "url", "url.generation.failed", "Failed to generate URL" );
        } else {
            String url = createCommand.getUrl();
            if (url == null || url.length() == 0) {
                errors.rejectValue("url", "url.empty", "URL cannot be empty");
            } else {
                if (url.length() > 12){
                    errors.rejectValue("url", "url.too.long", "URL is too long");
                }
                if (!Pattern.matches("[a-z0-9][_a-z0-9]*", url)) {
                    errors.rejectValue("url", "url.bad.characters", "URL can only contain a to z, 0-9 and underscore");
                }
            }
        }
    }



    public boolean supports(Class clazz)
    {
        return CreateCommand.class.isAssignableFrom(clazz);
    }
}