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.causeway.commons.io;
  
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.OutputStream;
  import java.nio.charset.Charset;
  import java.nio.charset.StandardCharsets;
  import java.util.function.Consumer;
  
  import org.springframework.util.function.ThrowingConsumer;
  import org.springframework.util.function.ThrowingSupplier;
  
  import org.apache.causeway.commons.functional.Try;
  
  import org.jspecify.annotations.NonNull;
  import lombok.SneakyThrows;
  
  /**
   * General purpose writable byte data sink.
   *
   * @since 2.0 {@index}
   */
  @FunctionalInterface
  public interface DataSink {
  
      /**
       * Offers this {@link DataSink}'s {@link OutputStream} to the caller,
       * so it can write data to it.
       */
      void writeAll(final @NonNull ThrowingConsumer<OutputStream> outputStreamConsumer);
  
      // -- FACTORIES
  
      /**
       * Acts as a no-op.
       */
      static DataSink none() {
          return consumingMapper -> {};
      }
  
      static DataSink ofOutputStreamSupplier(final @NonNull ThrowingSupplier<OutputStream> outputStreamSupplier) {
          return new DataSink() {
              @Override @SneakyThrows
              public void writeAll(final @NonNull ThrowingConsumer<OutputStream> outputStreamConsumer) {
                  try(final OutputStream os = outputStreamSupplier.get()) {
                      outputStreamConsumer.accept(os);
                  }
              }
          };
      }
  
      static DataSink ofByteArrayConsumer(final @NonNull ThrowingConsumer<byte[]> byteArrayConsumer, final int initalBufferSize) {
          return new DataSink() {
              @Override @SneakyThrows
              public void writeAll(final @NonNull ThrowingConsumer<OutputStream> outputStreamConsumer) {
                  try(final ByteArrayOutputStream bos = new ByteArrayOutputStream(initalBufferSize)) {
                      outputStreamConsumer.accept(bos);
                      byteArrayConsumer.accept(bos.toByteArray());
                  }
              }
          };
      }
  
      static DataSink ofByteArrayConsumer(final @NonNull ThrowingConsumer<byte[]> byteArrayConsumer) {
          // using the default initalBufferSize from constructor ByteArrayOutputStream()
          return ofByteArrayConsumer(byteArrayConsumer, 32);
      }
  
      static DataSink ofFile(final @NonNull File file) {
          return ofOutputStreamSupplier(()->Try.call(()->new FileOutputStream(file)).valueAsNonNullElseFail());
      }
  
      static DataSink ofStringConsumer(final @NonNull Consumer<String> stringConsumer, final @NonNull Charset charset) {
          return ofByteArrayConsumer(bytes->stringConsumer.accept(new String(bytes, charset)));
      }
  
      static DataSink ofStringUtf8Consumer(final @NonNull Consumer<String> stringUtf8Consumer) {
          return ofStringConsumer(stringUtf8Consumer, StandardCharsets.UTF_8);
      }
  
      static DataSink ofStringConsumer(final @NonNull StringBuilder stringConsumer, final @NonNull Charset charset) {
          return ofByteArrayConsumer(bytes->stringConsumer.append(new String(bytes, charset)));
      }
  
      /**
       * Example:
       * <pre>
       * var sb = new StringBuffer();
       * var dataSink = DataSink.ofStringUtf8Consumer(sb);
       * //... write to dataSink
       * String result = sb.toString(); // read the buffer
       * </pre>
       */
      static DataSink ofStringUtf8Consumer(final @NonNull StringBuilder stringUtf8Consumer) {
          return ofStringConsumer(stringUtf8Consumer, StandardCharsets.UTF_8);
      }
  
  }
  