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 org.apache.kafka.snapshot;
  
  import org.apache.kafka.common.record.MemoryRecords;
  import org.apache.kafka.common.record.UnalignedMemoryRecords;
  import org.apache.kafka.common.utils.ByteBufferOutputStream;
  import org.apache.kafka.server.common.OffsetAndEpoch;
  
  import java.nio.ByteBuffer;
  import java.util.function.Consumer;
  
  public final class MockRawSnapshotWriter implements RawSnapshotWriter {
      private final ByteBufferOutputStream data = new ByteBufferOutputStream(0);
      private final OffsetAndEpoch snapshotId;
      private final Consumer<ByteBuffer> frozenHandler;
  
      private boolean frozen = false;
      private boolean closed = false;
  
      public MockRawSnapshotWriter(
          OffsetAndEpoch snapshotId,
          Consumer<ByteBuffer> frozenHandler
      ) {
          this.snapshotId = snapshotId;
          this.frozenHandler = frozenHandler;
      }
  
      @Override
      public OffsetAndEpoch snapshotId() {
          return snapshotId;
      }
  
      @Override
      public long sizeInBytes() {
          ensureOpen();
          return data.position();
      }
  
      @Override
      public void append(UnalignedMemoryRecords records) {
          ensureNotFrozenOrClosed();
          data.write(records.buffer());
      }
  
      @Override
      public void append(MemoryRecords records) {
          ensureNotFrozenOrClosed();
          data.write(records.buffer());
      }
  
      @Override
      public boolean isFrozen() {
          return frozen;
      }
  
      @Override
      public void freeze() {
          ensureNotFrozenOrClosed();
  
          frozen = true;
          ByteBuffer buffer = data.buffer();
          buffer.flip();
  
          frozenHandler.accept(buffer);
      }
  
      @Override
      public void close() {
          ensureOpen();
          closed = true;
      }
  
      @Override
      public String toString() {
          return String.format("MockRawSnapshotWriter(snapshotId=%s, data=%s)", snapshotId, data.buffer());
      }
  
      private void ensureNotFrozenOrClosed() {
          if (frozen) {
              throw new IllegalStateException("Snapshot is already frozen " + snapshotId);
          }
          ensureOpen();
      }
  
      private void ensureOpen() {
          if (closed) {
              throw new IllegalStateException("Snapshot is already closed " + snapshotId);
          }
      }
  }
  