/*

 * Copyright (c) 2012, 2018, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.io.*;

import java.net.URL;

import java.util.Arrays;

import java.nio.channels.FileChannel;

import java.nio.file.FileVisitResult;

import java.nio.file.Files;

import java.nio.file.Path;

import java.nio.file.SimpleFileVisitor;

import java.nio.file.attribute.BasicFileAttributes;

import java.util.ArrayList;

import java.util.List;

/**

 * IOUtils

 *

 * A collection of static utility methods.

 */

public class IOUtils {

    public static void deleteRecursive(File path) throws IOException {

        if (!path.exists()) {

            return;

        }

        Path directory = path.toPath();

        Files.walkFileTree(directory, new SimpleFileVisitor<Path>() {

            @Override

            public FileVisitResult visitFile(Path file,

                            BasicFileAttributes attr) throws IOException {

                if (Platform.getPlatform() == Platform.WINDOWS) {

                    Files.setAttribute(file, "dos:readonly", false);

                }

                Files.delete(file);

                return FileVisitResult.CONTINUE;

            }

            @Override

            public FileVisitResult preVisitDirectory(Path dir,

                            BasicFileAttributes attr) throws IOException {

                if (Platform.getPlatform() == Platform.WINDOWS) {

                    Files.setAttribute(dir, "dos:readonly", false);

                }

                return FileVisitResult.CONTINUE;

            }

            @Override

            public FileVisitResult postVisitDirectory(Path dir, IOException e)

                            throws IOException {

                Files.delete(dir);

                return FileVisitResult.CONTINUE;

            }

        });

    }

    public static void copyRecursive(Path src, Path dest) throws IOException {

        Files.walkFileTree(src, new SimpleFileVisitor<Path>() {

            @Override

            public FileVisitResult preVisitDirectory(final Path dir,

                    final BasicFileAttributes attrs) throws IOException {

                Files.createDirectories(dest.resolve(src.relativize(dir)));

                return FileVisitResult.CONTINUE;

            }

            @Override

            public FileVisitResult visitFile(final Path file,

                    final BasicFileAttributes attrs) throws IOException {

                Files.copy(file, dest.resolve(src.relativize(file)));

                return FileVisitResult.CONTINUE;

            }

        });

    }

    public static void copyFromURL(URL location, File file) throws IOException {

        copyFromURL(location, file, false);

    }

    public static void copyFromURL(URL location, File file, boolean append)

            throws IOException {

        if (location == null) {

            throw new IOException("Missing input resource!");

        }

        if (file.exists() && !append) {

           file.delete();

        }

        InputStream in = location.openStream();

        FileOutputStream out = new FileOutputStream(file, append);

        byte[] buffer = new byte[1024];

        int len;

        while ((len = in.read(buffer)) != -1) {

            out.write(buffer, 0, len);

        }

        out.close();

        in.close();

        file.setReadOnly();

        file.setReadable(true, false);

    }

    public static void copyFile(File sourceFile, File destFile)

            throws IOException {

        destFile.getParentFile().mkdirs();

        //recreate the file as existing copy may have weird permissions

        destFile.delete();

        destFile.createNewFile();

        FileChannel source = null;

        FileChannel destination = null;

        source = new FileInputStream(sourceFile).getChannel();

        destination = new FileOutputStream(destFile).getChannel();

        if (destination != null && source != null) {

            destination.transferFrom(source, 0, source.size());

        }

        if (source != null) {

            source.close();

        }

        if (destination != null) {

            destination.close();

        }

        //preserve executable bit!

        if (sourceFile.canExecute()) {

            destFile.setExecutable(true, false);

        }

        if (!sourceFile.canWrite()) {

            destFile.setReadOnly();

        }

        destFile.setReadable(true, false);

    }

    public static long getFolderSize(File folder) {

        long foldersize = 0;

        File[] children = folder.listFiles();

        if (children != null) {

            for (File f : children) {

                if (f.isDirectory()) {

                    foldersize += getFolderSize(f);

                } else {

                    foldersize += f.length();

                }

            }

        }

        return foldersize;

    }

    // run "launcher paramfile" in the directory where paramfile is kept

    public static void run(String launcher, File paramFile, boolean verbose)

            throws IOException {

        if (paramFile != null && paramFile.exists()) {

            ProcessBuilder pb =

                    new ProcessBuilder(launcher, paramFile.getName());

            pb = pb.directory(paramFile.getParentFile());

            exec(pb, verbose);

        }

    }

    public static void exec(ProcessBuilder pb, boolean verbose)

            throws IOException {

        exec(pb, verbose, false);

    }

    public static void exec(ProcessBuilder pb, boolean verbose,

            boolean testForPresenseOnly) throws IOException {

        exec(pb, verbose, testForPresenseOnly, null);

    }

    public static void exec(ProcessBuilder pb, boolean verbose,

            boolean testForPresenseOnly, PrintStream consumer)

            throws IOException {

        pb.redirectErrorStream(true);

        Log.verbose("Running "

                + Arrays.toString(pb.command().toArray(new String[0]))

                + (pb.directory() != null ? (" in " + pb.directory()) : ""));

        Process p = pb.start();

        InputStreamReader isr = new InputStreamReader(p.getInputStream());

        BufferedReader br = new BufferedReader(isr);

        String lineRead;

        while ((lineRead = br.readLine()) != null) {

            if (consumer != null) {

                consumer.print(lineRead + '\n');

            } else {

               Log.verbose(lineRead);

            }

        }

        try {

            int ret = p.waitFor();

            if (ret != 0 && !(testForPresenseOnly && ret != 127)) {

                throw new IOException("Exec failed with code "

                        + ret + " command ["

                        + Arrays.toString(pb.command().toArray(new String[0]))

                        + " in " + (pb.directory() != null ?

                                pb.directory().getAbsolutePath() :

                                "unspecified directory"));

            }

        } catch (InterruptedException ex) {

        }

    }

    @SuppressWarnings("unchecked")

    private static Process startProcess(Object... args) throws IOException {

        final ArrayList<String> argsList = new ArrayList<>();

        for (Object a : args) {

            if (a instanceof List) {

                argsList.addAll((List)a);

            } else if (a instanceof String) {

                argsList.add((String)a);

            }

        }

        return Runtime.getRuntime().exec(

                argsList.toArray(new String[argsList.size()]));

    }

    private static void logErrorStream(Process p) {

        final BufferedReader err =

                new BufferedReader(new InputStreamReader(p.getErrorStream()));

        Thread t = new Thread(() -> {

            try {

                String line;

                while ((line = err.readLine()) != null) {

                    Log.error(line);

                }

            } catch (IOException ioe) {

                Log.verbose(ioe);

            }

        });

        t.setDaemon(true);

        t.start();

    }

    public static int getProcessOutput(List<String> result, Object... args)

            throws IOException, InterruptedException {

        final Process p = startProcess(args);

        List<String> list = new ArrayList<>();

        final BufferedReader in =

                new BufferedReader(new InputStreamReader(p.getInputStream()));

        Thread t = new Thread(() -> {

            try {

                String line;

                while ((line = in.readLine()) != null) {

                    list.add(line);

                }

            } catch (IOException ioe) {

            }

        });

        t.setDaemon(true);

        t.start();

        logErrorStream(p);

        int ret = p.waitFor();

        result.clear();

        result.addAll(list);

        return ret;

    }

}