// serverFileUtils.java 
// -------------------------------------------
// (C) by Michael Peter Christen; mc@yacy.net
// first published on http://www.anomic.de
// Frankfurt, Germany, 2004
// last major change: 05.08.2004
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

package de.anomic.server;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.io.Reader;
import java.io.Serializable;
import java.io.Writer;
import java.nio.charset.Charset;
import java.util.Comparator;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Map;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.TreeSet;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;

import de.anomic.kelondro.kelondroRow;
import de.anomic.kelondro.kelondroRowSet;
import de.anomic.server.logging.serverLog;
import de.anomic.tools.nxTools;

public final class serverFileUtils {

    private static final int DEFAULT_BUFFER_SIZE = 1024; // this is also the maximum chunk size
    
    public static long copy(final InputStream source, final OutputStream dest) throws IOException {
        return copy(source, dest, -1);
    }
    
    /**
     * Copies an InputStream to an OutputStream.
     * 
     * @param source InputStream
     * @param dest OutputStream
     * @param count the total amount of bytes to copy (-1 for all, else must be greater than zero)
     * @return Total number of bytes copied.
     * @throws IOException 
     * 
     * @see #copy(InputStream source, File dest)
     * @see #copyRange(File source, OutputStream dest, int start)
     * @see #copy(File source, OutputStream dest)
     * @see #copy(File source, File dest)
     */
    public static long copy(final InputStream source, final OutputStream dest, final long count) throws IOException {
        assert count == -1 || count > 0 : "precondition violated: count == -1 || count > 0 (nothing to copy)";
        if(count == 0) {
            // no bytes to copy
            return 0;
        }
        
        final byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];                
        int chunkSize = (int) ((count > 0) ? Math.min(count, DEFAULT_BUFFER_SIZE) : DEFAULT_BUFFER_SIZE);
        
        int c; long total = 0;
        while ((c = source.read(buffer, 0, chunkSize)) > 0) {
            dest.write(buffer, 0, c);
            dest.flush();
            total += c;
            
            if (count > 0) {
                chunkSize = (int) Math.min(count-total, DEFAULT_BUFFER_SIZE);
                if (chunkSize == 0) break;
            }
            
        }
        dest.flush();
        
        return total;
    }
    
    public static int copy(final File source, final Charset inputCharset, final Writer dest) throws IOException {
        InputStream fis = null;
        try {
            fis = new FileInputStream(source);
            return copy(fis, dest, inputCharset);
        } finally {
            if (fis != null) try { fis.close(); } catch (final Exception e) {}
        }
    }    
    
    public static int copy(final InputStream source, final Writer dest, final Charset inputCharset) throws IOException {
        final InputStreamReader reader = new InputStreamReader(source,inputCharset);
        return copy(reader,dest);
    }
    
    public static int copy(final String source, final Writer dest) throws IOException {
        dest.write(source);
        dest.flush();
        return source.length();
    }
    
    public static int copy(final Reader source, final Writer dest) throws IOException {        
        final char[] buffer = new char[DEFAULT_BUFFER_SIZE];
        int count = 0;
        int n = 0;
        try {
            while (-1 != (n = source.read(buffer))) {
                dest.write(buffer, 0, n);
                count += n;
            }
            dest.flush();
        } catch (final Exception e) {
            // an "sun.io.MalformedInputException: Missing byte-order mark" - exception may occur here
            throw new IOException(e.getMessage());
        }
        return count;
    }
    
    public static void copy(final InputStream source, final File dest) throws IOException {
        copy(source,dest,-1);
    }
    
    /**
     * Copies an InputStream to a File.
     * 
     * @param source    InputStream
     * @param dest    File
     * @param count the amount of bytes to copy
     * @throws IOException 
     * @see #copy(InputStream source, OutputStream dest)
     * @see #copyRange(File source, OutputStream dest, int start)
     * @see #copy(File source, OutputStream dest)
     * @see #copy(File source, File dest)
     */
    public static void copy(final InputStream source, final File dest, final long count) throws IOException {
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(dest);
            copy(source, fos, count);
        } finally {
            if (fos != null) try {fos.close();} catch (final Exception e) { serverLog.logWarning("FileUtils", "cannot close FileOutputStream for "+ dest +"! "+ e.getMessage()); }
        }
    }

    /**
     * Copies a part of a File to an OutputStream.
     * @param source    File
     * @param dest    OutputStream
     * @param start Number of bytes to skip from the beginning of the File
     * @throws IOException 
     * @see #copy(InputStream source, OutputStream dest)
     * @see #copy(InputStream source, File dest)
     * @see #copy(File source, OutputStream dest)
     * @see #copy(File source, File dest)
     */
    public static void copyRange(final File source, final OutputStream dest, final int start) throws IOException {
        InputStream fis = null;
        try {
            fis = new FileInputStream(source);
            final long skipped = fis.skip(start);
            if (skipped != start) throw new IllegalStateException("Unable to skip '" + start + "' bytes. Only '" + skipped + "' bytes skipped.");
            copy(fis, dest, -1);
        } finally {
            if (fis != null) try { fis.close(); } catch (final Exception e) {}
        }
    }

    /**
     * Copies a File to an OutputStream.
     * @param source    File
     * @param dest    OutputStream
     * @throws IOException 
     * @see #copy(InputStream source, OutputStream dest)
     * @see #copy(InputStream source, File dest)
     * @see #copyRange(File source, OutputStream dest, int start)
     * @see #copy(File source, File dest)
     */
    public static void copy(final File source, final OutputStream dest) throws IOException {
        InputStream fis = null;
        try {
            fis = new FileInputStream(source);
            copy(fis, dest, -1);
        } finally {
            if (fis != null) try { fis.close(); } catch (final Exception e) {}
        }
    }

    /**
     * Copies a File to a File.
     * @param source    File
     * @param dest    File
     * @param count the amount of bytes to copy
     * @throws IOException 
     * @see #copy(InputStream source, OutputStream dest)
     * @see #copy(InputStream source, File dest)
     * @see #copyRange(File source, OutputStream dest, int start)
     * @see #copy(File source, OutputStream dest)
     */
    public static void copy(final File source, final File dest) throws IOException {
        FileInputStream fis = null;
        FileOutputStream fos = null;
        try {
            fis = new FileInputStream(source);
            fos = new FileOutputStream(dest);
            copy(fis, fos, -1);
        } finally {
            if (fis != null) try {fis.close();} catch (final Exception e) {}
            if (fos != null) try {fos.close();} catch (final Exception e) {}
        }
    }

    public static void copy(final byte[] source, final OutputStream dest) throws IOException {
        dest.write(source, 0, source.length);
        dest.flush();
    }
    
    public static void copy(final byte[] source, final File dest) throws IOException {
        copy(new ByteArrayInputStream(source), dest);
    }

    public static byte[] read(final InputStream source) throws IOException {
        return read(source,-1);
    }
    
    public static byte[] read(final InputStream source, final int count) throws IOException {
        if (count > 0) {
            byte[] b = new byte[count];
            source.read(b, 0, count);
            return b;
        } else {
            final ByteArrayOutputStream baos = new ByteArrayOutputStream(512);
            copy(source, baos, count);
            baos.close();
            return baos.toByteArray();
        }
    }

    public static byte[] read(final File source) throws IOException {
        final byte[] buffer = new byte[(int) source.length()];
        InputStream fis = null;
        try {
            fis = new FileInputStream(source);
            int p = 0, c;
            while ((c = fis.read(buffer, p, buffer.length - p)) > 0) p += c;
        } finally {
            if (fis != null) try { fis.close(); } catch (final Exception e) {}
        }
        return buffer;
    }

    public static byte[] readAndZip(final File source) throws IOException {
        ByteArrayOutputStream byteOut = null;
        GZIPOutputStream zipOut = null;
        try {
            byteOut = new ByteArrayOutputStream((int)(source.length()/2));
            zipOut = new GZIPOutputStream(byteOut);
            copy(source, zipOut);
            zipOut.close();
            return byteOut.toByteArray();
        } finally {
            if (zipOut != null) try { zipOut.close(); } catch (final Exception e) {}
            if (byteOut != null) try { byteOut.close(); } catch (final Exception e) {}
        }
    }

    public static void writeAndGZip(final byte[] source, final File dest) throws IOException {
        FileOutputStream fos = null;
        try {
            fos = new FileOutputStream(dest);
            writeAndGZip(source, fos);
        } finally {
            if (fos != null) try {fos.close();} catch (final Exception e) {}
        }
    }

    public static void writeAndGZip(final byte[] source, final OutputStream dest) throws IOException {
        GZIPOutputStream zipOut = null;
        try {
            zipOut = new GZIPOutputStream(dest);
            copy(source, zipOut);
            zipOut.close();
        } finally {
            if (zipOut != null) try { zipOut.close(); } catch (final Exception e) {}
        }
    }
    
    /**
     * This function determines if a byte array is gzip compressed and uncompress it
     * @param source properly gzip compressed byte array
     * @return uncompressed byte array
     * @throws IOException
     */
    public static byte[] uncompressGZipArray(byte[] source) throws IOException {
    	if (source == null) return null;
    	
        // support of gzipped data (requested by roland)
		/* "Bitwise OR of signed byte value
		 * 
		 * [...] Values loaded from a byte array are sign extended to 32 bits before
		 * any any bitwise operations are performed on the value. Thus, if b[0]
		 * contains the value 0xff, and x is initially 0, then the code ((x <<
		 * 8) | b[0]) will sign extend 0xff to get 0xffffffff, and thus give the
		 * value 0xffffffff as the result. [...]" findbugs description of BIT_IOR_OF_SIGNED_BYTE
		 */
        if ((source.length > 1) && (((source[1] << 8) | (source[0] & 0xff)) == GZIPInputStream.GZIP_MAGIC)) {
            System.out.println("DEBUG: uncompressGZipArray - uncompressing source");
            try {
                final ByteArrayInputStream byteInput = new ByteArrayInputStream(source);
                final ByteArrayOutputStream byteOutput = new ByteArrayOutputStream(source.length / 5);
                final GZIPInputStream zippedContent = new GZIPInputStream(byteInput);
                final byte[] data = new byte[1024];
                int read = 0;
                
                // reading gzip file and store it uncompressed
                while((read = zippedContent.read(data, 0, 1024)) != -1) {
                    byteOutput.write(data, 0, read);
                }
                zippedContent.close();
                byteOutput.close();   
                
                source = byteOutput.toByteArray();
            } catch (final Exception e) {
                if (!e.getMessage().equals("Not in GZIP format")) {
                    throw new IOException(e.getMessage());
                }
            }
        }    
        
        return source;
    }

    public static HashSet<String> loadList(final File file) {
        final HashSet<String> set = new HashSet<String>();
        BufferedReader br = null;
        try {
            br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
            String line;
            while ((line = br.readLine()) != null) {
                line = line.trim();
                if ((line.length() > 0) && (!(line.startsWith("#")))) set.add(line.trim().toLowerCase());
            }
            br.close();
        } catch (final IOException e) {
        } finally {
            if (br != null) try { br.close(); } catch (final Exception e) {}
        }
        return set;
    }

    public static Map<String, String> loadHashMap(final File f) {
        // load props
        try {
            final byte[] b = read(f);
            return nxTools.table(nxTools.strings(b));
        } catch (final IOException e2) {
            System.err.println("ERROR: " + f.toString() + " not found in settings path");
            return null;
        }
    }
    
    public static void saveMap(final File file, final Map<String, String> props, final String comment) throws IOException {
        PrintWriter pw = null;
        final File tf = new File(file.toString() + "." + (System.currentTimeMillis() % 1000));
        pw = new PrintWriter(new BufferedOutputStream(new FileOutputStream(tf)));
        pw.println("# " + comment);
        String key, value;
        for (final Map.Entry<String, String> entry: props.entrySet()) {
            key = entry.getKey();
            if (entry.getValue() == null) {
                value = "";
            } else {
                value = entry.getValue().replaceAll("\n", "\\\\n");
            }
            pw.println(key + "=" + value);
        }
        pw.println("# EOF");
        pw.close();
        forceMove(tf, file);
    }

    public static Set<String> loadSet(final File file, final int chunksize, final boolean tree) throws IOException {
        final Set<String> set = (tree) ? (Set<String>) new TreeSet<String>() : (Set<String>) new HashSet<String>();
        final byte[] b = read(file);
        for (int i = 0; (i + chunksize) <= b.length; i++) {
            set.add(new String(b, i, chunksize));
        }
        return set;
    }

    public static Set<String> loadSet(final File file, final String sep, final boolean tree) throws IOException {
        final Set<String> set = (tree) ? (Set<String>) new TreeSet<String>() : (Set<String>) new HashSet<String>();
        final byte[] b = read(file);
        final StringTokenizer st = new StringTokenizer(new String(b, "UTF-8"), sep);
        while (st.hasMoreTokens()) {
            set.add(st.nextToken());
        }
        return set;
    }

    public static void saveSet(final File file, final String format, final Set<String> set, final String sep) throws IOException {
        final File tf = new File(file.toString() + ".tmp" + (System.currentTimeMillis() % 1000));
        OutputStream os = null;
        if ((format == null) || (format.equals("plain"))) {
            os = new BufferedOutputStream(new FileOutputStream(tf));
        } else if (format.equals("gzip")) {
            os = new GZIPOutputStream(new FileOutputStream(tf));
        } else if (format.equals("zip")) {
            final ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(file));
            String name = file.getName();
            if (name.endsWith(".zip")) name = name.substring(0, name.length() - 4);
            zos.putNextEntry(new ZipEntry(name + ".txt"));
            os = zos;
        }
        if(os != null) {
            for (final Iterator<String> i = set.iterator(); i.hasNext(); ) {
                os.write((i.next()).getBytes());
                if (sep != null) os.write(sep.getBytes());
            }
            os.close();
        }
        forceMove(tf, file);
    }

    public static void saveSet(final File file, final String format, final kelondroRowSet set, final String sep) throws IOException {
        final File tf = new File(file.toString() + ".tmp" + (System.currentTimeMillis() % 1000));
        OutputStream os = null;
        if ((format == null) || (format.equals("plain"))) {
            os = new BufferedOutputStream(new FileOutputStream(tf));
        } else if (format.equals("gzip")) {
            os = new GZIPOutputStream(new FileOutputStream(tf));
        } else if (format.equals("zip")) {
            final ZipOutputStream zos = new ZipOutputStream(new FileOutputStream(file));
            String name = file.getName();
            if (name.endsWith(".zip")) name = name.substring(0, name.length() - 4);
            zos.putNextEntry(new ZipEntry(name + ".txt"));
            os = zos;
        }
        if(os != null) {
            final Iterator<kelondroRow.Entry> i = set.iterator();
            String key;
            if (i.hasNext()) {
                key = new String(i.next().getColBytes(0));
                os.write(key.getBytes());
            }
            while (i.hasNext()) {
                key = new String((i.next()).getColBytes(0));
                if (sep != null) os.write(sep.getBytes());
                os.write(key.getBytes());
            }
            os.close();
        }
        forceMove(tf, file);
    }

    /**
     * @param from
     * @param to
     * @throws IOException
     */
    private static void forceMove(final File from, final File to) throws IOException {
        if(!(to.delete() && from.renameTo(to))) {
            // do it manually
            copy(from, to);
            if(!from.delete())
                from.deleteOnExit();
        }
    }
    
    /**
    * Moves all files from a directory to another.
    * @param from_dir    Directory which contents will be moved.
    * @param to_dir    Directory to move into. It must exist already.
    */
    public static void moveAll(final File from_dir, final File to_dir) {
        if (!(from_dir.isDirectory())) return;
        if (!(to_dir.isDirectory())) return;
        final String[] list = from_dir.list();
        for (int i = 0; i < list.length; i++) {
        	if(!new File(from_dir, list[i]).renameTo(new File(to_dir, list[i])))
        		serverLog.logWarning("serverFileUtils", "moveAll(): could not move from "+ from_dir + list[i] +" to "+ to_dir + list[i]);
        }
    }
    

    public static class dirlistComparator implements Comparator<File>, Serializable {
        
        /**
		 * generated serial
		 */
		private static final long serialVersionUID = -5196490300039230135L;

		public int compare(final File file1, final File file2) {
            if (file1.isDirectory() && !file2.isDirectory()) {
                return -1;
            } else if (!file1.isDirectory() && file2.isDirectory()) {
                return 1;
            } else {
                return file1.getName().compareToIgnoreCase(file2.getName());
            }
        }
    }    

    public static void main(final String[] args) {
        try {
            writeAndGZip("ein zwei drei, Zauberei".getBytes(), new File("zauberei.txt.gz"));
        } catch (final IOException e) {
            e.printStackTrace();
        }
    }

    /**
     * copies the input stream to one output stream (byte per byte)
     * @param in
     * @param out
     * @return number of copies bytes
     * @throws IOException
     */
    public static int copyToStream(final BufferedInputStream in, final BufferedOutputStream out) throws IOException {
        int count = 0;
        // copy bytes
        int b;
        while ((b = in.read()) != -1) {
            count++;
            out.write(b);
        }
        out.flush();
        return count;
    }
    
    /**
     * copies the input stream to both output streams (byte per byte)
     * @param in
     * @param out0
     * @param out1
     * @return number of copies bytes
     * @throws IOException
     */
    public static int copyToStreams(final BufferedInputStream in, final BufferedOutputStream out0, final BufferedOutputStream out1) throws IOException {
        assert out0 != null;
        assert out1 != null;
        
        int count = 0;
        // copy bytes
        int b;
        while((b = in.read()) != -1) {
            count++;
            out0.write(b);
            out1.write(b);
        }
        out0.flush();
        out1.flush();
        return count;
    }

    /**
     * copies the input stream to all writers (byte per byte)
     * @param data
     * @param writer
     * @param charSet
     * @return
     * @throws IOException
     */
    public static int copyToWriter(final BufferedInputStream data, final BufferedWriter writer, final Charset charSet) throws IOException {
        // the docs say: "For top efficiency, consider wrapping an InputStreamReader within a BufferedReader."
        final Reader sourceReader = new InputStreamReader(data, charSet);
        
        int count = 0;
        // copy bytes
        int b;
        while((b = sourceReader.read()) != -1) {
            count++;
            writer.write(b);
        }
        writer.flush();
        return count;
    }
    
    public static int copyToWriters(final BufferedInputStream data, final BufferedWriter writer0, final BufferedWriter writer1, final Charset charSet) throws IOException {
        // the docs say: "For top efficiency, consider wrapping an InputStreamReader within a BufferedReader."
        assert writer0 != null;
        assert writer1 != null;
        final Reader sourceReader = new InputStreamReader(data, charSet);
        
        int count = 0;
        // copy bytes
        int b;
        while((b = sourceReader.read()) != -1) {
            count++;
            writer0.write(b);
            writer1.write(b);
        }
        writer0.flush();
        writer1.flush();
        return count;
    }
    
    /**
     * delete a directory
     * if the directory is not empty, delete also everything inside
     * @param directory
     */
    public static void deleteDirectory(final File directory) {
        final String[] list = directory.list();
        if (list != null) {
            File object;
            for (int i = list.length - 1; i >= 0; i--) {
                object = new File(directory, list[i]);
                if (object.isFile()) {
                    object.delete();
                } else {
                    deleteDirectory(object);
                }
            }
        }
        directory.delete();
    }
}