/*
 * Copyright 2004 Gunn Software Ltd. http://www.gunnsoft.com.au/
 *
 * 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 net.sf.tapestrypublisher;

import java.io.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

/**
 * @author Paul Stanton
 */
public class IOUtils
{
	/**
	 * copies a file creating parent directories for new file if necissary
	 * @param src
	 * @param dest
	 * @throws IOException
	 */
	public static void copy(File src, File dest) throws IOException
	{
		dest.getParentFile().mkdirs();
		FileInputStream in = null;
		FileOutputStream out = null;
		try
		{
			in = new FileInputStream(src);
			out = new FileOutputStream(dest);
			readInto(in, out);
		}
		finally
		{
			close(in);
			close(out);
		}
	}

	/**
	 * convenience method closes io resources
	 */
	public static void close(Object obj)
	{
		if (obj == null)
			return;

		if (obj instanceof OutputStream)
		{
			try
			{
				((OutputStream) obj).flush();
			}
			catch (Exception e)
			{}
			try
			{
				((OutputStream) obj).close();
			}
			catch (Exception e)
			{}
		}
		else if (obj instanceof InputStream)
		{
			try
			{
				((InputStream) obj).close();
			}
			catch (Exception e)
			{}
		}
		else if (obj instanceof Writer)
		{
			try
			{
				((Writer) obj).flush();
			}
			catch (Exception e)
			{}
			try
			{
				((Writer) obj).close();
			}
			catch (Exception e)
			{}
		}
		else if (obj instanceof Reader)
		{
			try
			{
				((Reader) obj).close();
			}
			catch (Exception e)
			{}
		}
		else
			throw new IllegalArgumentException("unhandled class : " + obj.getClass().getName());
	}

	/**
	 * @param in
	 * @return the content contained by in
	 * @throws IOException
	 */
	public static String istreamToString(InputStream in) throws IOException
	{
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		String message;
		try
		{
			IOUtils.readInto(in, out);
			message = out.toString();
		}
		finally
		{
			IOUtils.close(out);
		}
		return message;
	}

	/**
	 * reads from the input stream into the output stream
	 */
	private static void readInto(InputStream in, OutputStream out) throws IOException
	{
		byte[] buf = new byte[1024];
		int i = 0;
		while ((i = in.read(buf)) != -1)
			out.write(buf, 0, i);
	}

	/**
	 * @param url
	 * @return the document content represented by this url
	 * @throws MalformedURLException
	 * @throws IOException
	 */
	public static String getWebDocument(String url) throws MalformedURLException, IOException
	{
		URLConnection conn = new URL(url).openConnection();
		conn.connect();

		InputStream in = null;
		try
		{
			in = conn.getInputStream();
			return IOUtils.istreamToString(in);
		}
		finally
		{
			IOUtils.close(in);
		}
	}

	/**
	 * writes data to a file
	 * @param file
	 * @param bytes
	 * @throws IOException
	 */
	public static void writeToFile(File file, byte[] bytes) throws IOException
	{
		file.getParentFile().mkdirs();
		FileOutputStream out = new FileOutputStream(file);
		try
		{
			out.write(bytes);
		}
		finally
		{
			close(out);
		}
	}
}