/*
 * 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.jclouds.iam.functions;

import static com.google.common.base.Preconditions.checkNotNull;

import javax.inject.Inject;

import org.jclouds.collect.IterableWithMarker;
import org.jclouds.collect.internal.Arg0ToPagedIterable;
import org.jclouds.iam.IAMApi;
import org.jclouds.iam.domain.Role;
import org.jclouds.iam.features.RoleApi;

import com.google.common.annotations.Beta;
import com.google.common.base.Function;
import com.google.common.base.Optional;

@Beta
public class RolesToPagedIterable extends Arg0ToPagedIterable<Role, RolesToPagedIterable> {

   private final RoleApi api;

   @Inject
   protected RolesToPagedIterable(IAMApi api) {
      this.api = checkNotNull(api, "api").getRoleApi();
   }

   @Override
   protected Function<Object, IterableWithMarker<Role>> markerToNextForArg0(Optional<Object> pathPrefix) {
      if (pathPrefix.isPresent())
         return new ListRolesUnderPathPrefixAtMarker(api, pathPrefix.get().toString());
      return new ListRolesAtMarker(api);
   }

   private static class ListRolesUnderPathPrefixAtMarker implements Function<Object, IterableWithMarker<Role>> {
      private final RoleApi api;
      private final String pathPrefix;

      @Inject
      protected ListRolesUnderPathPrefixAtMarker(RoleApi api, String pathPrefix) {
         this.api = checkNotNull(api, "api");
         this.pathPrefix = checkNotNull(pathPrefix, "pathPrefix");
      }

      public IterableWithMarker<Role> apply(Object input) {
         return api.listPathPrefixAt(pathPrefix, input.toString());
      }

      public String toString() {
         return "ListRolesUnderPathPrefixAtMarker(" + pathPrefix + ")";
      }
   }

   private static class ListRolesAtMarker implements Function<Object, IterableWithMarker<Role>> {
      private final RoleApi api;

      @Inject
      protected ListRolesAtMarker(RoleApi api) {
         this.api = checkNotNull(api, "api");
      }

      public IterableWithMarker<Role> apply(Object input) {
         return api.listAt(input.toString());
      }

      public String toString() {
         return "listRolesAtMarker()";
      }
   }
}