/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 io.milton.servlet;

import java.io.File;
import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

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

public class StaticResourceFilter implements Filter {
    
    private final Logger log = LoggerFactory.getLogger(StaticResourceFilter.class);
    
    private FilterConfig filterConfig = null;
    
    public void doFilter(ServletRequest request, ServletResponse response,FilterChain chain)throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) request;
        String s = MiltonUtils.stripContext(req);
        log.debug("url: " + s);
        s = "WEB-INF/static/" + s;
        log.debug("check path: " + s);
        String path = filterConfig.getServletContext().getRealPath(s);
        log.debug("real path: " + path);
        File f = null; 
        if( path != null && path.length() > 0 ) {
            f = new File(path);
        }
        if( f != null && f.exists() && !f.isDirectory() ) {  // can't forward to a folder
            log.debug("static file exists. forwarding..");
            req.getRequestDispatcher(s).forward(request,response);
        } else {
            log.debug("static file does not exist, continuing chain..");
            chain.doFilter(request,response);
        }
    }
    
    
    public FilterConfig getFilterConfig() {
        return (this.filterConfig);
    }
    
    public void destroy() {
    }
    
    public void init(FilterConfig filterConfig) {
        this.filterConfig = filterConfig;
    }
    
}