/*
    * 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 com.addthis.codec.binary;
  
  import java.io.ByteArrayOutputStream;
  import java.io.IOException;
  import java.io.OutputStream;
  
  import java.util.Stack;
  
  import com.addthis.basis.util.Bytes;
  
  final class BufferOut {
  
      ByteArrayOutputStream        out;
      Stack<ByteArrayOutputStream> stack;
  
      BufferOut() {
          stack = new Stack<>();
          push();
      }
  
      public OutputStream out() {
          return out;
      }
  
      public void push() {
          stack.push(new ByteArrayOutputStream());
          out = stack.peek();
      }
  
      public void pop() throws IOException {
          ByteArrayOutputStream last = stack.pop();
          out = stack.peek();
          Bytes.writeLength(last.size(), out());
          last.writeTo(out());
      }
  
      @Override
      public String toString() {
          return "BufferOut:" + (out != null ? out.size() : -1);
      }
  }