/**
    *
    * Copyright (C) 2011 Cloud Conscious, LLC. <info@cloudconscious.com>
    *
    * ====================================================================
    * 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.jclouds.openstack.functions;
  
  import static com.google.common.base.Preconditions.checkNotNull;
  import static org.jclouds.http.HttpUtils.releasePayload;
  import static org.jclouds.openstack.reference.AuthHeaders.AUTH_TOKEN;
  import static org.jclouds.openstack.reference.AuthHeaders.URL_SUFFIX;
  
  import java.net.URI;
  import java.util.Map.Entry;
  
  import javax.annotation.Resource;
  import javax.inject.Inject;
  import javax.inject.Provider;
  import javax.ws.rs.core.UriBuilder;
  
  import org.jclouds.http.HttpRequest;
  import org.jclouds.http.HttpResponse;
  import org.jclouds.logging.Logger;
  import org.jclouds.openstack.OpenStackAuthAsyncClient.AuthenticationResponse;
  import org.jclouds.rest.InvocationContext;
  
  import com.google.common.annotations.VisibleForTesting;
  import com.google.common.base.Function;
  import com.google.common.collect.ImmutableMap;
  import com.google.common.collect.ImmutableMap.Builder;
  
  /**
   * This parses {@link AuthenticationResponse} from HTTP headers.
   * 
   * @author Adrian Cole
   */
  public class ParseAuthenticationResponseFromHeaders implements Function<HttpResponse, AuthenticationResponse>,
           InvocationContext<ParseAuthenticationResponseFromHeaders> {
  
     @Resource
     protected Logger logger = Logger.NULL;
  
     private final Provider<UriBuilder> uriBuilderProvider;
     private String hostToReplace;
  
     @Inject
     public ParseAuthenticationResponseFromHeaders(Provider<UriBuilder> uriBuilderProvider) {
        this.uriBuilderProvider = uriBuilderProvider;
     }
  
     /**
      * parses the http response headers to create a new {@link AuthenticationResponse} object.
      */
     public AuthenticationResponse apply(HttpResponse from) {
        releasePayload(from);
        Builder<String, URI> builder = ImmutableMap.<String, URI> builder();
        for (Entry<String, String> entry : from.getHeaders().entries()) {
           if (entry.getKey().endsWith(URL_SUFFIX))
              builder.put(entry.getKey(), getURI(entry.getValue()));
        }
        AuthenticationResponse response = new AuthenticationResponse(checkNotNull(from.getFirstHeaderOrNull(AUTH_TOKEN),
                 AUTH_TOKEN), builder.build());
        logger.debug("will connect to: ", response);
        return response;
     }
  
     // TODO: find the swift configuration or bug related to returning localhost
     protected URI getURI(String headerValue) {
        if (headerValue == null)
           return null;
        URI toReturn = URI.create(headerValue);
        if (!"127.0.0.1".equals(toReturn.getHost()))
           return toReturn;
        return uriBuilderProvider.get().uri(toReturn).host(hostToReplace).build();
     }
  
     @Override
     public ParseAuthenticationResponseFromHeaders setContext(HttpRequest request) {
        return setHostToReplace(request.getEndpoint().getHost());
     }
  
     @VisibleForTesting
     ParseAuthenticationResponseFromHeaders setHostToReplace(String hostToReplace) {
        this.hostToReplace = hostToReplace;
        return this;
     }
 }