/**
 * This file Copyright (c) 2003-2012 Magnolia International
 * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
 *
 *
 * This file is dual-licensed under both the Magnolia
 * Network Agreement and the GNU General Public License.
 * You may elect to use one or the other of these licenses.
 *
 * This file is distributed in the hope that it will be
 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
 * implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
 * Redistribution, except as permitted by whichever of the GPL
 * or MNA you select, is prohibited.
 *
 * 1. For the GPL license (GPL), you can redistribute and/or
 * modify this file under the terms of the GNU General
 * Public License, Version 3, as published by the Free Software
 * Foundation.  You should have received a copy of the GNU
 * General Public License, Version 3 along with this program;
 * if not, write to the Free Software Foundation, Inc., 51
 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * 2. For the Magnolia Network Agreement (MNA), this file
 * and the accompanying materials are made available under the
 * terms of the MNA which accompanies this distribution, and
 * is available at http://www.magnolia-cms.com/mna.html
 *
 * Any modifications to this file must keep this entire header
 * intact.
 *
 */
package info.magnolia.cms.security;

import info.magnolia.context.MgnlContext;

import java.io.IOException;

import javax.jcr.Session;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/**
 * This Filter protects URI as defined by ROLE(s)/GROUP(s) ACL.
 *
 * @version $Id$
 */
public class URISecurityFilter extends BaseSecurityFilter {

    private static final Logger log = LoggerFactory.getLogger(URISecurityFilter.class);

    public static final String URI_REPOSITORY = "uri";

    public static final String URI_WORKSPACE = "default";

    /**
     * Checks access from Listener / Authenticator / AccessLock.
     * @param request HttpServletRequest as received by the service method
     * @param response HttpServletResponse as received by the service method
     * @return boolean <code>true</code> if access to the resource is allowed
     * @throws IOException can be thrown when the servlet is unable to write to the response stream
     */
    @Override
    public boolean isAllowed(HttpServletRequest request, HttpServletResponse response) throws IOException {
        // todo MAGNOLIA-1617 move this to separate filter
        final IPSecurityManager ipSecurityManager = IPSecurityManager.Factory.getInstance();
        if (!ipSecurityManager.isAllowed(request)) {
            response.setStatus(HttpServletResponse.SC_FORBIDDEN);
            return false;
        }

        if (Lock.isSystemLocked()) {
            // todo - move Lock checks to separate filter
            response.setStatus(HttpServletResponse.SC_SERVICE_UNAVAILABLE);
            return false;
        }

        final boolean authorized = isAuthorized(request);
        if (!authorized) {
            final int statusCode = SecurityUtil.isAnonymous() ? HttpServletResponse.SC_UNAUTHORIZED : HttpServletResponse.SC_FORBIDDEN;
            response.setStatus(statusCode);
        }
        return authorized;
    }

    /**
     * Validates user permissions on URI.
     *
     * @deprecated since 4.5 use {@link #isAuthorized(HttpServletRequest)} instead.
     */
    @Deprecated
    protected boolean isAuthorized(AccessManager accessManager, HttpServletRequest request) {
        return isAuthorized(request);
    }

    /**
     * Validates user permissions on URI.
     */
    protected boolean isAuthorized(HttpServletRequest request) {
        String permission;
        if (request.getMethod().equalsIgnoreCase("HEAD") || request.getMethod().equalsIgnoreCase("GET")) {
            permission = Session.ACTION_READ;
        } else {
            permission = Session.ACTION_ADD_NODE;
        }

        final String uri = MgnlContext.getAggregationState().getCurrentURI();

        boolean grant = PermissionUtil.isGranted("uri", uri, permission);
        log.debug("user {} has " + (grant ? "" : "NOT ") + "been granted permission {} to access uri {}", new Object[] { MgnlContext.getUser().getName(), permission, uri });
        return grant;
    }

}