/**
    *
    * 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.rest.internal;
  
  import static com.google.common.collect.Sets.difference;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.delegationMap;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.getHttpMethods;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToBinderParamAnnotation;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToEndpointAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToEndpointParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToFormParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToHeaderParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToMatrixParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToParamParserAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToPartParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToPathParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToPostParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToQueryParamAnnotations;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexOfParamToWrapWithAnnotation;
  import static org.jclouds.rest.internal.RestAnnotationProcessor.methodToIndexesOfOptions;
  
  import java.lang.reflect.Method;
  
  import javax.annotation.Resource;
  import javax.inject.Named;
  import javax.inject.Singleton;
  import javax.ws.rs.Path;
  import javax.ws.rs.PathParam;
  
  import org.jclouds.http.HttpRequest;
  import org.jclouds.logging.Logger;
  import org.jclouds.rest.annotations.Delegate;
  import org.jclouds.rest.internal.RestAnnotationProcessor.MethodKey;
  
  import com.google.common.base.Function;
  import com.google.common.collect.ImmutableSet;
  import com.google.common.collect.Multimap;
  import com.google.inject.Inject;
  import com.google.inject.Injector;
  import com.google.inject.Key;
  import com.google.inject.Provides;
  
  /**
   * seeds the annotation cache
   * 
   * @author Adrian Cole
   */
  
  @Singleton
  public class SeedAnnotationCache implements Function<Class<?>, Boolean> {
     @Resource
     protected Logger logger = Logger.NULL;
  
     protected final Multimap<String, String> constants;
     protected final Injector injector;
  
     @Inject
     public SeedAnnotationCache(Injector injector, @Named("CONSTANTS") Multimap<String, String> constants) {
        this.injector = injector;
        this.constants = constants;
     }
  
     public void bindConstant(Method method) {
        String key = method.getAnnotation(PathParam.class).value();
        String value = injector.getInstance(Key.get(String.class, method.getAnnotation(Named.class)));
        constants.put(key, value);
     }
  
     public Boolean apply(Class<?> declaring) {
        for (Method method : difference(ImmutableSet.copyOf(declaring.getMethods()), ImmutableSet.copyOf(Object.class
                 .getMethods()))) {
           if (isHttpMethod(method) || method.isAnnotationPresent(Delegate.class)) {
              for (int index = 0; index < method.getParameterTypes().length; index++) {
                 methodToIndexOfParamToBinderParamAnnotation.get(method).get(index);
                 methodToIndexOfParamToWrapWithAnnotation.get(method).get(index);
                 methodToIndexOfParamToHeaderParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToMatrixParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToFormParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToQueryParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToEndpointAnnotations.get(method).get(index);
                 methodToIndexOfParamToEndpointParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToPathParamAnnotations.get(method).get(index);
                 methodToIndexOfParamToPostParamAnnotations.get(method).get(index);
                methodToIndexOfParamToParamParserAnnotations.get(method).get(index);
                methodToIndexOfParamToPartParamAnnotations.get(method).get(index);
                methodToIndexesOfOptions.get(method);
             }
             delegationMap.put(new MethodKey(method), method);
          } else if (isConstantDeclaration(method)) {
             bindConstant(method);
          } else if (!method.getDeclaringClass().equals(declaring)) {
             logger.trace("skipping potentially overridden method %s", method);
          } else if (method.isAnnotationPresent(Provides.class)) {
             logger.trace("skipping provider method %s", method);
          } else {
             logger.trace("Method is not annotated as either http or constant: %s", method);
          }
       }
       return true;
    }
 
    public static boolean isHttpMethod(Method method) {
       return method.isAnnotationPresent(Path.class) || getHttpMethods(method) != null
                || ImmutableSet.copyOf(method.getParameterTypes()).contains(HttpRequest.class);
    }
 
    public static boolean isConstantDeclaration(Method method) {
       return method.isAnnotationPresent(PathParam.class) && method.isAnnotationPresent(Named.class);
    }
 }