/*
 * Copyright 2003,2004 The Apache Software Foundation.
 * 
 * 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.apache.commons.io;

import java.io.File;
import java.util.Date;

import org.apache.commons.io.testtools.*;

/**
 * This is used to test FileUtils for correctness.
 *
 * @author Alban Peignier
 */
public class FileUtilsFileNewerTestCase extends FileBasedTestCase {

    // Test data
    private static final int FILE1_SIZE = 1;
    private static final int FILE2_SIZE = 1024 * 4 + 1;

    private File m_testFile1;
    private File m_testFile2;

    public FileUtilsFileNewerTestCase(String name) {
        super(name);
        
        m_testFile1 = new File(getTestDirectory(), "file1-test.txt");
        m_testFile2 = new File(getTestDirectory(), "file2-test.txt");
    }

    /** @see junit.framework.TestCase#setUp() */
    protected void setUp() throws Exception {
        getTestDirectory().mkdirs();
        createFile(m_testFile1, FILE1_SIZE);
        createFile(m_testFile2, FILE2_SIZE);
    }

    /** @see junit.framework.TestCase#tearDown() */
    protected void tearDown() throws Exception {
        m_testFile1.delete();
        m_testFile2.delete();
    }

    /**
     * Tests the isFileNewer(File, *) methods which a "normal" file.
     *
     * @see FileUtils#isFileNewer(File, long)
     * @see FileUtils#isFileNewer(File, Date)
     * @see FileUtils#isFileNewer(File, File)
     */
    public void testIsFileNewer() {
        if (!m_testFile1.exists())
            throw new IllegalStateException("The m_testFile1 should exist");

        long fileLastModified = m_testFile1.lastModified();
        final long ONE_SECOND = 1000;

        testIsFileNewer("one second earlier is not newer" , m_testFile1, fileLastModified + ONE_SECOND, false);
        testIsFileNewer("same time is not newer" , m_testFile1, fileLastModified, false);
        testIsFileNewer("one second later is newer" , m_testFile1, fileLastModified - ONE_SECOND, true);
    }

    /**
     * Tests the isFileNewer(File, *) methods which a not existing file.
     *
     * @see FileUtils#isFileNewer(File, long)
     * @see FileUtils#isFileNewer(File, Date)
     * @see FileUtils#isFileNewer(File, File)
     */
    public void testIsFileNewerImaginaryFile() {
        File imaginaryFile = new File(getTestDirectory(), "imaginaryFile");
        if (imaginaryFile.exists())
            throw new IllegalStateException("The imaginary File exists");

        testIsFileNewer("imaginary file can be newer" , imaginaryFile, 0, false);
    }

    /**
     * Tests the isFileNewer(File, *) methods which the specified conditions.
     * 

     * Creates :
     * 

     * 
a Date which represents the time reference
     * 
a temporary file with the same last modification date than the time reference
     * 
     * Then compares (with the needed isFileNewer method) the last modification date of 
     * the specified file with the specified time reference, the created Date and the temporary 
     * file.
     * 

     * The test is successfull if the three comparaisons return the specified wanted result.
     *
     * @param description describes the tested situation
     * @param file the file of which the last modification date is compared
     * @param timeMillis the time reference measured in milliseconds since the epoch 
     *
     * @see FileUtils#isFileNewer(File, long)
     * @see FileUtils#isFileNewer(File, Date)
     * @see FileUtils#isFileNewer(File, File)
     */
    protected void testIsFileNewer(String description, File file, long time, boolean wantedResult)  {
        assertEquals(description + " - time", wantedResult, FileUtils.isFileNewer(file, time));
        assertEquals(description + " - date", wantedResult, FileUtils.isFileNewer(file, new Date(time)));
        
        File temporaryFile = m_testFile2;

        temporaryFile.setLastModified(time);
        if (temporaryFile.lastModified() != time)
            throw new IllegalStateException("The temporary file hasn't the right last modification date");
        assertEquals(description + " - file", wantedResult, FileUtils.isFileNewer(file, temporaryFile));
    }

    /**
     * Tests the isFileNewer(File, long) method without specifying a File.
     * 

     * The test is successfull if the method throws an IllegalArgumentException. 
     */
    public void testIsFileNewerNoFile() {
        try {
            FileUtils.isFileNewer(null,0);
            fail("File not specified");
        } catch (IllegalArgumentException e) {}
    }

    /**
     * Tests the isFileNewer(File, Date) method without specifying a Date.
     * 

     * The test is successfull if the method throws an IllegalArgumentException. 
     */
    public void testIsFileNewerNoDate() {
        try {
            FileUtils.isFileNewer(m_testFile1, (Date) null);
            fail("Date not specified");
        } catch (IllegalArgumentException e) {}
    }

    /**
     * Tests the isFileNewer(File, File) method without specifying a reference File.
     * 

     * The test is successfull if the method throws an IllegalArgumentException. 
     */
    public void testIsFileNewerNoFileReference() {
        try {
            FileUtils.isFileNewer(m_testFile1, (File) null);
            fail("Reference file not specified");
        } catch (IllegalArgumentException e) {}
    }
}