package org.jboss.resteasy.client.core.extractors;



import org.jboss.resteasy.annotations.Body;

import org.jboss.resteasy.annotations.LinkHeaderParam;

import org.jboss.resteasy.annotations.Status;

import org.jboss.resteasy.client.ClientExecutor;

import org.jboss.resteasy.client.ClientRequest;

import org.jboss.resteasy.client.ProxyFactory;

import org.jboss.resteasy.spi.Link;

import org.jboss.resteasy.spi.LinkHeader;

import org.jboss.resteasy.spi.ResteasyProviderFactory;

import org.jboss.resteasy.util.IsHttpMethod;



import javax.ws.rs.HeaderParam;

import javax.ws.rs.core.Response;

import java.lang.reflect.Method;

import java.net.MalformedURLException;

import java.net.URI;

import java.net.URISyntaxException;

import java.net.URL;

import java.util.Set;



/**

 * This class represents the method level creation of a "rich response object"

 * that has the @ResponseObject annotation. These EntityExtractors will be used

 * to implment methods of ResponseObject via ResponseObjectEntityExtractor

 *

 * @author <a href="mailto:sduskis@gmail.com">Solomon Duskis</a>

 * @version $Revision: 1 $

 * @see EntityExtractor, ResponseObjectEntityExtractor

 */

public class ResponseObjectEntityExtractorFactory extends DefaultEntityExtractorFactory

{



   @SuppressWarnings("unchecked")

   public EntityExtractor createExtractor(final Method method)

   {

      final Class<?> returnType = method.getReturnType();

      if (method.isAnnotationPresent(Status.class))

      {

         if (returnType == Integer.class || returnType == int.class)

         {



            return new EntityExtractor<Integer>()

            {

               public Integer extractEntity(ClientRequestContext context, Object... args)

               {

                  return context.getClientResponse().getStatus();

               }

            };

         }

         else if (returnType == Response.Status.class)

         {

            return createStatusExtractor(false);

         }

      }



      if (method.isAnnotationPresent(Body.class))

      {

         return new BodyEntityExtractor(method);

      }



      final HeaderParam headerParam = method.getAnnotation(HeaderParam.class);

      if (headerParam != null)

      {

         return new EntityExtractor()

         {

            public Object extractEntity(ClientRequestContext context, Object... args)

            {

               return context.getClientResponse().getHeaders().getFirst(headerParam.value());

            }

         };

      }



      final LinkHeaderParam link = method.getAnnotation(LinkHeaderParam.class);

      if (link != null)

      {

         return processLinkHeader(method, returnType, link);

      }



      if (returnType == ClientRequest.class)

      {

         return new EntityExtractor()

         {

            public Object extractEntity(ClientRequestContext context, Object... args)

            {

               return context.getRequest();

            }

         };

      }



      if (Response.class.isAssignableFrom(returnType))

      {

         return createResponseTypeEntityExtractor(method);

      }



      if (returnType == LinkHeader.class)

      {

         return new EntityExtractor()

         {

            public Object extractEntity(ClientRequestContext context, Object... args)

            {

               return context.getClientResponse().getLinkHeader();

            }

         };

      }



      return null;

   }



   private EntityExtractor processLinkHeader(final Method method, final Class<?> returnType,

                                             final LinkHeaderParam link)

   {

      if ("".equals(link.rel()) && "".equals(link.title()))

      {

         throw new RuntimeException(String.format(

                 "You must set either LinkHeaderParam.rel() or LinkHeaderParam.title() for on %s.%s",

                 method.getClass().getName(), method.getName()));

      }

      if (!"".equals(link.rel()) && !"".equals(link.title()))

      {

         throw new RuntimeException(

                 String

                         .format(

                                 "You can only set one of  LinkHeaderParam.rel() and LinkHeaderParam.title() for on %s.%s",

                                 method.getClass().getName(), method.getName()));

      }



      if (returnType == Link.class)

      {

         return new EntityExtractor()

         {

            public Object extractEntity(ClientRequestContext context, Object... args)

            {

               return getLink(link, context);

            }

         };

      }



      if (isInvokerMethod(method))

      {

         return new EntityExtractor()

         {

            public Object extractEntity(ClientRequestContext context, Object... args)

            {

               URI uri = getURI(method, link, context);

               if (uri == null)

                  return null;



               ClientRequest request = context.getRequest();

               EntityExtractorFactory extractor = context.getExtractorFactory();

               ResteasyProviderFactory provider = request.getProviderFactory();

               ClientExecutor executor = request.getExecutor();

               return ProxyFactory.createClientInvoker(method.getClass(), method, uri,

                       executor, provider, extractor).invoke(args);

            }

         };

      }



      if (returnType == String.class)

      {

         return new EntityExtractor<String>()

         {

            public String extractEntity(ClientRequestContext context, Object... args)

            {

               Link link2 = getLink(link, context);

               return link2 == null ? null : link2.getHref();

            }

         };

      }



      if (returnType == URL.class)

      {

         return new EntityExtractor<URL>()

         {

            public URL extractEntity(ClientRequestContext context, Object... args)

            {

               return getURL(method, link, context);

            }

         };

      }

      if (returnType == URI.class)

      {

         return new EntityExtractor<URI>()

         {

            public URI extractEntity(ClientRequestContext context, Object... args)

            {

               return getURI(method, link, context);

            }

         };

      }



      if (returnType.equals(ClientRequest.class))

      {

         return new EntityExtractor<ClientRequest>()

         {

            public ClientRequest extractEntity(ClientRequestContext context, Object... args)

            {

               URI uri = getURI(method, link, context);

               return uri == null ? null : context.getRequest().createSubsequentRequest(uri);

            }

         };

      }



      return null;

   }



   private static boolean isInvokerMethod(Method method)

   {

      Set<String> httpMethods = IsHttpMethod.getHttpMethods(method);

      return httpMethods != null && httpMethods.size() == 1;

   }



   private Link getLink(final LinkHeaderParam link, ClientRequestContext context)

   {

      LinkHeader linkHeader = context.getClientResponse().getLinkHeader();

      if (!"".equals(link.rel()))

         return linkHeader.getLinkByRelationship(link.rel());

      else

         return linkHeader.getLinkByTitle(link.title());

   }



   private URI getURI(final Method method, Link link)

   {

      if (link == null)

      {

         return null;

      }

      try

      {

         return new URI(link.getHref());

      }

      catch (URISyntaxException e)

      {

         throw new RuntimeException(String.format("Could not create a URI for %s in %s.%s", link

                 .getHref(), method.getClass().getName(), method.getName()), e);

      }

   }



   private URI getURI(final Method method, final LinkHeaderParam link, ClientRequestContext context)

   {

      return getURI(method, getLink(link, context));

   }



   private URL getURL(final Method method, final LinkHeaderParam link, ClientRequestContext context)

   {

      URI uri = getURI(method, link, context);

      try

      {

         return uri == null ? null : uri.toURL();

      }

      catch (MalformedURLException e)

      {

         throw new RuntimeException(String.format("Could not create a URL for %s in %s.%s", uri

                 .toASCIIString(), method.getClass().getName(), method.getName()), e);

      }

   }

}