/**
    * 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.creadur.tentacles;
  
  import org.apache.logging.log4j.*;
  import java.io.*;
  import java.net.URL;
  import java.nio.file.Files;
  import java.util.zip.ZipInputStream;
  
  public class IOSystem {
  	private static final Logger LOG = LogManager.getLogger(IOSystem.class);
  
  	public String slurp(final File file) throws IOException {
  		final ByteArrayOutputStream out = new ByteArrayOutputStream();
  		copy(file, out);
  		return out.toString();
  	}
  
  	public String slurp(final URL url) throws IOException {
  		final ByteArrayOutputStream out = new ByteArrayOutputStream();
  		copy(url.openStream(), out);
  		return out.toString();
  	}
  
  	public void writeString(final File file, final String string) throws IOException {
  		final FileWriter out = new FileWriter(file);
  		try {
  			final BufferedWriter bufferedWriter = new BufferedWriter(out);
  			try {
  				bufferedWriter.write(string);
  				bufferedWriter.newLine();
  			} finally {
  				close(bufferedWriter);
  			}
  		} finally {
  			close(out);
  		}
  	}
  
  	private void copy(final File from, final OutputStream to) throws IOException {
  		final InputStream read = read(from);
  		try {
  			copy(read, to);
  		} finally {
  			close(read);
  		}
  	}
  
  	public void copy(final InputStream from, final File to) throws IOException {
  		final OutputStream write = write(to);
  		try {
  			copy(from, write);
  		} finally {
  			close(write);
  		}
  	}
  
  	private void copy(final InputStream from, final OutputStream to) throws IOException {
  		final byte[] buffer = new byte[1024];
  		int length = 0;
  		while ((length = from.read(buffer)) != -1) {
  			to.write(buffer, 0, length);
  		}
  		to.flush();
  	}
  
  	public void copy(final byte[] from, final File to) throws IOException {
  		copy(new ByteArrayInputStream(from), to);
  	}
  
  	public ZipInputStream unzip(final File file) throws IOException {
  		final InputStream read = read(file);
  		return new ZipInputStream(read);
  	}
  
  	public void close(final Closeable closeable) {
  		if (closeable == null) {
  			return;
  		}
  		try {
  			if (closeable instanceof Flushable) {
  				((Flushable) closeable).flush();
  			}
  		} catch (final IOException e) {
             LOG.trace("Error when trying to flush before closing {}", closeable, e);
 		}
 		try {
 			closeable.close();
 		} catch (final IOException e) {
             LOG.trace("Error when trying to close {}", closeable, e);
 		}
 	}
 
 	public OutputStream write(final File destination) throws IOException {
 		final OutputStream out = Files.newOutputStream(destination.toPath());
 		return new BufferedOutputStream(out, 32768);
 	}
 
 	public InputStream read(final File source) throws IOException {
 		final InputStream in = Files.newInputStream(source.toPath());
 		return new BufferedInputStream(in, 32768);
 	}
 
 	public byte[] read(final InputStream in) throws IOException {
 		final ByteArrayOutputStream out = new ByteArrayOutputStream();
 		copy(in, out);
 		out.close();
 		return out.toByteArray();
 	}
 }