content: /*
   *  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
   *
   *      https://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.ivy.osgi.repo;
  
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.List;
  import java.util.NoSuchElementException;
  import java.util.Set;
  
  public class AggregatedRepoDescriptor extends RepoDescriptor {
  
      private List<RepoDescriptor> repos;
  
      public AggregatedRepoDescriptor(List<RepoDescriptor> repos) {
          this.repos = repos;
      }
  
      @Override
      public Iterator<ModuleDescriptorWrapper> getModules() {
          final Iterator<RepoDescriptor> itRepos = repos.iterator();
          return new Iterator<ModuleDescriptorWrapper>() {
  
              private Iterator<ModuleDescriptorWrapper> current = null;
  
              private ModuleDescriptorWrapper next = null;
  
              public boolean hasNext() {
                  while (next == null) {
                      if (current == null) {
                          if (!itRepos.hasNext()) {
                              return false;
                          }
                          RepoDescriptor repo = itRepos.next();
                          current = repo.getModules();
                      }
                      if (current.hasNext()) {
                          next = current.next();
                      } else {
                          current = null;
                      }
                  }
                  return true;
              }
  
              public ModuleDescriptorWrapper next() {
                  if (!hasNext()) {
                      throw new NoSuchElementException();
                  }
                  ModuleDescriptorWrapper ret = next;
                  next = null;
                  return ret;
              }
  
              public void remove() {
                  throw new UnsupportedOperationException();
              }
          };
      }
  
      @Override
      public Set<String> getCapabilities() {
          Set<String> ret = new HashSet<>();
          for (RepoDescriptor repo : repos) {
              Set<String> capabilities = repo.getCapabilities();
              if (capabilities != null) {
                  ret.addAll(capabilities);
              }
          }
          return ret;
      }
  
      @Override
      public Set<ModuleDescriptorWrapper> findModules(String requirement, String value) {
          Set<ModuleDescriptorWrapper> ret = new HashSet<>();
          for (RepoDescriptor repo : repos) {
              Set<ModuleDescriptorWrapper> modules = repo.findModules(requirement, value);
              if (modules != null) {
                  ret.addAll(modules);
              }
          }
          return ret;
      }
  
      @Override
      public Set<String> getCapabilityValues(String capabilityName) {
          Set<String> ret = new HashSet<>();
          for (RepoDescriptor repo : repos) {
              Set<String> capabilityValues = repo.getCapabilityValues(capabilityName);
              if (capabilityValues != null) {
                  ret.addAll(capabilityValues);
              }
          }
          return ret;
      }
  
  }
  