/**
 * 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 org.apache.camel.http.common;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;

import org.apache.camel.support.RestConsumerContextPathMatcher;

/**
 * A default implementation of {@link org.apache.camel.http.common.ServletResolveConsumerStrategy}.
 */
public class HttpServletResolveConsumerStrategy implements ServletResolveConsumerStrategy {

    @Override
    public HttpConsumer resolve(HttpServletRequest request, Map<String, HttpConsumer> consumers) {
        return doResolve(request, request.getMethod(), consumers);
    }

    @Override
    public boolean isHttpMethodAllowed(HttpServletRequest request, String method, Map<String, HttpConsumer> consumers) {
        return doResolve(request, method, consumers) != null;
    }

    protected HttpConsumer doResolve(HttpServletRequest request, String method, Map<String, HttpConsumer> consumers) {
        String path = request.getPathInfo();
        if (path == null) {
            return null;
        }
        HttpConsumer answer = consumers.get(path);

        List<HttpConsumer> candidates = resolveCandidates(request, method, consumers);
        if (candidates.size() == 1) {
            answer = candidates.get(0);
        } else {
            // extra filter by restrict
        	ArrayList<HttpConsumer> list = new ArrayList<HttpConsumer>();
        	for (Iterator iterator = candidates.iterator(); iterator.hasNext();) {
				HttpConsumer httpConsumer = (HttpConsumer) iterator.next();
				if (matchRestMethod(method, httpConsumer.getEndpoint().getHttpMethodRestrict())) {
					list.add(httpConsumer);
				}
			}
            if (list.size() == 1) {
                answer = candidates.get(0);
            }
        }

        return answer;
    }

    private List<HttpConsumer> resolveCandidates(HttpServletRequest request, String method, Map<String, HttpConsumer> consumers) {
        String path = request.getPathInfo();

        List<HttpConsumer> candidates = new ArrayList<>();
        for (String key : consumers.keySet()) {
            //We need to look up the consumer path here
            String consumerPath = consumers.get(key).getPath();
            HttpConsumer consumer = consumers.get(key);
            boolean matchOnUriPrefix = consumer.getEndpoint().isMatchOnUriPrefix();
            // Just make sure the we get the right consumer path first
            if (RestConsumerContextPathMatcher.matchPath(path, consumerPath, matchOnUriPrefix)) {
                candidates.add(consumer);
            }
        }
        return candidates;
    }

    private static boolean matchRestMethod(String method, String restrict) {
        return restrict == null || restrict.toLowerCase(Locale.ENGLISH).contains(method.toLowerCase(Locale.ENGLISH));
    }

}
