/*
 *
 * Derby - Class org.apache.derbyTesting.junit.SupportFilesSetup
 *
 * 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.derbyTesting.junit;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;

import junit.extensions.TestSetup;
import junit.framework.Test;
import org.apache.derbyTesting.functionTests.util.PrivilegedFileOpsForTests;

/**
 * A decorator that copies test resources from the classpath
 * into the file system at setUp time. Resources are named
 * relative to org/apache/derbyTesting/, e.g. the name
 * passed into the constructor should be something like
 * funtionTests/test/lang/mytest.sql
 * <BR>
 * Read only resources are placed into ${user.dir}/extin/name
 * Read-write resources are placed into ${user.dir}/extinout/name
 * write only output files can be created in ${user.dir}/extout
 * 
 * These locations map to entries in the test policy file that
 * have restricted permissions granted.
 * 
 * All the three folders are created even if no files are
 * copied into them.
 * 
 * In each case the name of a file is the base name of the resource,
 * no package structure is retained.
 * 
 * A test may access such a resource using either files or URLs.
 * The static utility methods must be used to obtain the location
 * of any resource. In the future this decorator may create sub-folders
 * to ensure that tests run in paralled do not interfere with each other.
 * 
 * tearDown removes the three folders and their contents.
 * 
 */
public class SupportFilesSetup extends TestSetup {

    public  static  final   String  EXTIN = "extin";
    public  static  final   String  EXTINOUT = "extinout";
    public  static  final   String  EXTOUT = "extout";
    
    private String[] readOnly;
    private String[] readWrite;
    private String[] readOnlyTargetFileNames;
    private String[] readWriteTargetFileNames;

    /**
     * Create all the folders but don't copy any resources.
     */
    public SupportFilesSetup(Test test)
    {
        this(test, (String[]) null, (String[]) null);
    }

    /**
     * Create all the folders and copy a set of resources into
     * the read only folder.
     */
    public SupportFilesSetup(Test test, String[] readOnly)
    {
        this(test, readOnly, (String[]) null, (String[]) null, (String[]) null);
    }
    
    /**
     * Create all the folders, copy a set of resources into
     * the read only folder and copy a set of resources into
     * the read write folder.
   */
    public SupportFilesSetup(Test test, String[] readOnly, String[] readWrite)
    {
        this(test, readOnly, readWrite, (String[]) null, (String[]) null);
    }
    
    /**
     * Create all the folders, copy a set of resources into
     * the read only folder and copy a set of resources into
     * the read write folder. If specified, use the specific target file
     * supplied by the caller.
     */
    public SupportFilesSetup
        (Test test, String[] readOnly, String[] readWrite, String[] readOnlyTargetFileNames, String[] readWriteTargetFileNames)
    {
        super(test);
        this.readOnly = readOnly;
        this.readWrite = readWrite;
        this.readOnlyTargetFileNames = readOnlyTargetFileNames;
        this.readWriteTargetFileNames = readWriteTargetFileNames;
    }
    
    protected void setUp() throws PrivilegedActionException, IOException
    {
        privCopyFiles(EXTIN, readOnly, readOnlyTargetFileNames);
        privCopyFiles(EXTINOUT, readWrite, readWriteTargetFileNames);
        privCopyFiles(EXTOUT, (String[]) null, (String[]) null);
    }
    
    protected void tearDown()
    {
        DropDatabaseSetup.removeDirectory(EXTIN);
        DropDatabaseSetup.removeDirectory(EXTINOUT);
        DropDatabaseSetup.removeDirectory(EXTOUT);
    }
    
    public  static   void privCopyFiles(final String dirName, final String[] resources, final String[] targetNames)
    throws PrivilegedActionException
    {
        AccessController.doPrivileged(new PrivilegedExceptionAction<Void>() {
            public Void run() throws IOException, PrivilegedActionException {
              copyFiles(dirName, resources, targetNames);
              return null;
            }
        });

    }
    
    private static  void copyFiles(String dirName, String[] resources, String[] targetNames)
        throws PrivilegedActionException, IOException
    {
        File dir = new File(dirName);
        dir.mkdir();
        
        if (resources == null)
            return;

        for (int i = 0; i < resources.length; i++)
        {
            String name =
                "org/apache/derbyTesting/".concat(resources[i]);
            
            String baseName;

            if ( targetNames == null )
            {
                // by default, just the same file name as the source file
                baseName = name.substring(name.lastIndexOf('/') + 1);
            }
            else
            {
                // we let the caller override the target file name
                baseName = targetNames[ i ];
            }
            
                        URL url = BaseTestCase.getTestResource(name);
            assertNotNull(name, url);
            
            InputStream in = BaseTestCase.openTestResource(url);
            
            File copy = new File(dir, baseName);
            copy.delete();
            
            OutputStream out = new FileOutputStream(copy);
            
            byte[] buf = new byte[32*1024];
            
            for (;;) {
                int read = in.read(buf);
                if (read == -1)
                    break;
                out.write(buf, 0, read);
            }
            in.close();
            out.flush();
            out.close();
        }
    }
    
    /**
     * Obtain the URL to the local copy of a read-only resource.
     * @param name Base name for the resouce.
     */
    public static URL getReadOnlyURL(String name) throws MalformedURLException
    {
        return getURL(getReadOnly(name));
    }
    /**
     * Obtain the URL to the local copy of a read-write resource.
     * @param name Base name for the resouce.
     */
    public static URL getReadWriteURL(String name) throws MalformedURLException
    {
        return getURL(getReadWrite(name));
    }
    /**
     * Obtain the URL to the local copy of a write-only resource.
     * @param name Base name for the resouce.
     */
    public static URL getWriteOnlyURL(String name) throws MalformedURLException
    {
        return getURL(getWriteOnly(name));
    }
    
    
    /**
     * Obtain a File for the local copy of a read-only resource.
     * @param name Base name for the resouce.
     */
    public static File getReadOnly(String name)
    {
        return getFile(EXTIN, name);
    }
    
    /**
     * Get the full name of the file.
     * @param name Base name for the resource.
     */
    public static String getReadOnlyFileName(final String name)
    {
        return AccessController.doPrivileged(
                new PrivilegedAction<String>() {
            public String run() {
                return getReadOnly(name).getAbsolutePath();
            }
        });
    }
    
    /**
     * Get the full name of the file.
     * @param name short name of file
     * @return absolute path of file in EXTINOUT
     */
    public static String getReadWriteFileName(final String name)
    {
        return AccessController.doPrivileged(
                new PrivilegedAction<String>() {
            public String run() {
                return getReadWrite(name).getAbsolutePath();
            }
        });
    }
    
    /**
     * Obtain a File for the local copy of a read-write resource.
     * @param name Base name for the resource.
     */
    public static File getReadWrite(String name)
    {
        return getFile(EXTINOUT, name);
    }
    /**
     * Obtain a File for the local copy of a write-only resource.
     * @param name Base name for the resouce.
     */
    public static File getWriteOnly(String name)
    {
        return getFile(EXTOUT, name);
    }
    
    private static File getFile(String dirName, String name)
    {
        File dir = new File(dirName);
        return new File(dir, name);
    }
    
    private static URL getURL(final File file) throws MalformedURLException
    {
        try {
            return AccessController.doPrivileged(
                    new PrivilegedExceptionAction<URL>() {
                public URL run() throws MalformedURLException {
                    return file.toURI().toURL();
                }
            });
        } catch (PrivilegedActionException e) {
            throw (MalformedURLException) e.getException();
        } 
    }


    public static void deleteFile(final String fileName) 
    {
        deleteFile( new File(fileName) );
    }

    public static void deleteFile(final File file ) 
    {
        if (PrivilegedFileOpsForTests.exists(file)) {
            assertTrue(PrivilegedFileOpsForTests.delete(file));
        }
    }
}