/*
Copyright 2018 Red Hat, Inc.
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.jboss.as.controller.persistence;

import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;

/**
 *
 * @author <a href="padamec@redhat.com">Petr Adamec</a>
 */
public class ConfigurationFileUnitTestCase {
    private static final String BASE_CONFIGURATION_NAME = "standalone.xml";
    private static final String HISTORY_CONFIGURATION_NAME = "20180101-000000000standalone.xml";
    private static final String CONFIGURATION_DIR = "WFCORE-3513";
    private static final String HISTORY_DIRECTORY = "standalone_xml_history";
    private static final String SNAPSHOT_DIRECTORY = "snapshot";

    File configurationDir;
    File historyDirectory;
    File snapshotsDirectory;

    @Before
    public void createDirectoryAndFile(){
        File targetDir = new File("target");
        if (!targetDir.exists() ) {
            Assert.fail("The target directory does not exist.");
        }
        configurationDir = createDirectory(targetDir, CONFIGURATION_DIR);
        historyDirectory = createDirectory(configurationDir, HISTORY_DIRECTORY);
        snapshotsDirectory = createDirectory(historyDirectory, SNAPSHOT_DIRECTORY);
    }

    /**
     * Create directory in parent one.</br>
     * If parent directory does not exist set fail
     * @param parent parent directory
     * @param name name of new directory
     * @return new File of directory
     */
    private File createDirectory(File parent, String name) {
        checkDir(parent);
        File newDir = new File(parent, name);
        newDir.mkdir();
        if(!newDir.exists()){
            Assert.fail("Could not create directory "+name);
        }
        return newDir;
    }


    /**
     * Create file with content
     * @param dir parent directory
     * @param name name of file
     * @param contents content of file
     * @return new File with name and contents at the parent directory
     */
    private File createFile(File dir, String name, String contents){
        checkDir(dir);
        File newFile = new File(dir, name);
        if (contents != null) {
            try{
                Files.write(newFile.toPath(), contents.getBytes(StandardCharsets.UTF_8));
            }catch (IOException e){
                Assert.fail("Could not create new file "+name);
            }
        }
        return newFile;
    }

    private void checkDir(File dir){
        if(!dir.exists() || !dir.isDirectory()){
            Assert.fail("Directory for new file doesn't exist or isn't directory");
        }
    }

    /**
     * Test crating instance of ConfigurationFile. </br>
     * A configuration file that does not match the snapshot naming pattern is present in the snapshot directory.
     * Constructor should not throw an exception.</br>
     * For more information visit <a href="issues.jboss.org/browse/WFCORE-3513">https://issues.jboss.org/browse/WFCORE-3513</a>
     */
    @Test
    public void testConstructorWithCorrectFileAtSnapshot() {
        try{
            createFile(configurationDir, BASE_CONFIGURATION_NAME, "");
            createFile(snapshotsDirectory, BASE_CONFIGURATION_NAME, "");
            createFile(snapshotsDirectory, HISTORY_CONFIGURATION_NAME, "");
            new ConfigurationFile(configurationDir, BASE_CONFIGURATION_NAME, BASE_CONFIGURATION_NAME, true);
        } catch (StringIndexOutOfBoundsException e){
            Assert.fail("Could not create an instance of ConfigurationFile with standalone.xml in the snapshot directory.");
        }
    }

    /**
     * Delete file or directory recursively
     * @param f file or directory which should be deleted
     */
    private void  delete(File f){
        if (f.isDirectory()) {
            for (File c : f.listFiles())
                delete(c);
        }
        if (!f.delete()) {
            Assert.fail("Could not delete file "+f.getName());
        }
    }



    @After
    public void cleanUp(){
        if (configurationDir != null) {
            delete(configurationDir);
        }
    }
}

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