/*
 * Copyright 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.wamblee.photos.security;

import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;

import org.wamblee.photos.wicket.BasePage;
import org.wamblee.security.authorization.AllOperation;
import org.wamblee.security.authorization.AuthorizationResult;
import org.wamblee.security.authorization.IsaOperationCondition;
import org.wamblee.security.authorization.RegexpPathCondition;
import org.wamblee.security.authorization.UrlAuthorizationRule;
import org.wamblee.security.authorization.UserCondition;

/**
 * AUthorization rule for pages.
 */
@Entity
@DiscriminatorValue("PAGE")
public class PageAuthorizationRule extends UrlAuthorizationRule {

    /**
     * Type-safe construction of page authorization rule.
     * 
     * @param aResult
     *            Result.
     * @param aUserCondition
     *            User condition.
     * @param aPageList
     *            A list of page names.
     */
    public PageAuthorizationRule(AuthorizationResult aResult,
        UserCondition aUserCondition, Class<? extends BasePage>... aPageList) {
        super(aResult, aUserCondition, new RegexpPathCondition(
            getPageRegex(aPageList)), BasePage.class,
            new IsaOperationCondition(AllOperation.class));
    }

    /**
     * Converts a list of page names into a regular expression for the pages.
     * 
     * @param aPageList
     *            List of pages.
     * @return Regexp matching any of the given pagenames.
     */
    private static String getPageRegex(Class<? extends BasePage>[] aPageList) {
        String result = "";
        for (int i = 0; i < aPageList.length; i++) {
            if (result.length() == 0) {
                result = "/" + aPageList[i].getSimpleName();
            } else {
                result = result + "|/" + aPageList[i].getSimpleName();
            }
        }
        return result;
    }

    /**
     * Constructor for OR mapping.
     */
    protected PageAuthorizationRule() {
        super();
    }

    /* (non-Javadoc)
     * @see org.wamblee.security.authorization.UrlAuthorizationRule#getResourcePath(java.lang.Object)
     */
    @Override
    protected String getResourcePath(Object aResource) {
        BasePage page = (BasePage) aResource;
        return "/" + page.getClass().getSimpleName();
    }
}