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
   *
   *     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 accord.impl.list;
  
  import java.util.Arrays;
  import java.util.Map;
  import java.util.TreeMap;
  import java.util.function.Function;
  import java.util.stream.Collectors;
  
  import accord.api.Data;
  import accord.api.Key;
  import accord.api.Update;
  import accord.local.CommandStore;
  import accord.primitives.Keys;
  import accord.primitives.Participants;
  import accord.primitives.Ranges;
  import accord.primitives.Seekables;
  import accord.primitives.Timestamp;
  import accord.utils.Invariants;
  import accord.api.AsyncExecutor;
  import accord.utils.Timestamped;
  
  public class ListUpdate extends TreeMap<Key, Integer> implements Update
  {
      private final Function<? super CommandStore, AsyncExecutor> executor;
  
      public ListUpdate(Function<? super CommandStore, AsyncExecutor> executor)
      {
          this.executor = executor;
      }
  
      @Override
      public Seekables<?, ?> keys()
      {
          return new Keys(navigableKeySet());
      }
  
      @Override
      public ListWrite apply(Timestamp executeAt, Data read)
      {
          ListWrite write = new ListWrite(executor);
          Map<Key, Timestamped<int[]>> data = (ListData)read;
          for (Map.Entry<Key, Integer> e : entrySet())
          {
              Timestamped<int[]> prev = data.get(e.getKey());
              Invariants.require(prev != null && prev.timestamp.compareTo(executeAt) < 0);
              write.put(e.getKey(), append(prev.data, e.getValue()));
          }
          return write;
      }
  
      @Override
      public Update slice(Ranges ranges)
      {
          ListUpdate result = new ListUpdate(executor);
          for (Map.Entry<Key, Integer> e : entrySet())
          {
              if (ranges.contains(e.getKey()))
                  result.put(e.getKey(), e.getValue());
          }
          return result;
      }
  
      @Override
      public Update intersecting(Participants<?> participants)
      {
          ListUpdate result = new ListUpdate(executor);
          for (Map.Entry<Key, Integer> e : entrySet())
          {
              if (participants.contains(e.getKey().toUnseekable()))
                  result.put(e.getKey(), e.getValue());
          }
          return result;
      }
  
      @Override
      public Update merge(Update other)
      {
          ListUpdate result = new ListUpdate(executor);
          result.putAll(this);
          result.putAll((ListUpdate) other);
          return result;
      }
  
      private static int[] append(int[] to, int append)
      {
          to = Arrays.copyOf(to, to.length + 1);
          to[to.length - 1] = append;
          return to;
      }
  
      @Override
      public String toString()
      {
          return entrySet().stream()
                           .map(e -> e.getKey() + ":" + e.getValue())
                           .collect(Collectors.joining(", ", "{", "}"));
      }
  }
  