/*
 * Copyright 2005 the original author or authors.
 * 
 * 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 org.wamblee.io;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;

import junit.framework.Assert;

/**
 * TestData provides a convenient interface for managing test output files.  
 * 
 * @author Erik Brakkee
 */
public final class TestData {

	private Object _testcase;
	private File _root;

	/**
	 * Test data to be constructed in the setUp of a test.
	 * {@link #clean()} must be called to make sure that this 
	 * directory is empty before executing a test. 
	 */
	public TestData(Object aTestcase) {
		_testcase = aTestcase;
		_root = getTestRootDir(aTestcase);
	}

	/**
	 * Obtain root directory of JUnit tests.
	 * 
	 * @return Directory name.
	 */
	private static File getTestRootDir(Object aTestcase) {
		return FileSystemUtils.getTestOutputDir(aTestcase.getClass());
	}

	/**
	 * Returns a temporary directory.
	 * 
	 * @return Temporary directory.
	 */
	public File getTmpDir() {
		return new File(_root, "tmpdir");
	}

	/**
	 * Cleans up the test output directory.
	 */
	public void clean() {
		FileSystemUtils.deleteDirRecursively(_root);
	}

	/**
	 * Recursively copy a directory contents to the test output directory.
	 * 
	 * @param sSrc
	 *            Source directory to copy.
	 */
	public void copyDir(File aSrc) {
		FileSystemUtils.copyDir(aSrc, _root);
	}
	
	/**
	 * Copies a classpath resource to a relative path in the test output
	 * directory.
	 * 
	 * @param aResource
	 *            Resource to copy.
	 * @param aRelativePath
	 *            Relative path.
	 */
	public void copyResource(String aResource, String aRelativePath) {
		try {
			InputStream is = new ClassPathResource(aResource).getInputStream();
			FileOutputStream fos = new FileOutputStream(new File(_root,
					aRelativePath));
			FileSystemUtils.copyStream(is, fos);
		} catch (IOException e) {
			e.printStackTrace();
			Assert.fail(e.getMessage());
		}
	}

	/**
	 * Copies a resource to the root directory of the test output.
	 * @param aResource Resource.
	 */
	public void copyResource(String aResource) {
		String basename = new File(aResource).getName();
		copyResource(aResource, basename);
	}

	/**
	 * Deletes a file or directory relative to the test output root.
	 * 
	 * @param aRelative
	 *            Relative path. The testcase will fail if the file or directory
	 *            cannot be removed.
	 */
	public void delete(String aRelative) {
		FileSystemUtils.delete(new File(_root, aRelative));
	}

	/**
	 * Deletes a directory including its contents. 
	 * @param aRelative Relative path. 
	 */
	public void deleteDir(String aRelative) { 
		FileSystemUtils.deleteDir(new File(_root, aRelative));
	}

	/**
	 * Deletes a directory recursively. 
	 * @param aRelative Relative path. 
	 */
	public void deleteDirRecursively(String aRelative) { 
		FileSystemUtils.deleteDir(new File(_root, aRelative));
	}
	
	/**
	 * Gets a file object for a relative path. 
	 */
	public File getFile(String aRelative) { 
		return new File(_root, aRelative); 
	}
}