/*

 * Copyright (c) 2003, 2013, 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

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package com.sun.java.util.jar.pack;

import java.io.BufferedInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.nio.ByteBuffer;

import java.util.jar.JarOutputStream;

import java.util.jar.Pack200;

import java.util.zip.CRC32;

import java.util.zip.Deflater;

import java.util.zip.ZipEntry;

import java.util.zip.ZipOutputStream;

class NativeUnpack {

    // Pointer to the native unpacker obj

    private long unpackerPtr;

    // Input stream.

    private BufferedInputStream in;

    private static synchronized native void initIDs();

    // Starts processing at the indicated position in the buffer.

    // If the buffer is null, the readInputFn callback is used to get bytes.

    // Returns (s<<32|f), the number of following segments and files.

    private synchronized native long start(ByteBuffer buf, long offset);

    // Returns true if there's another, and fills in the parts.

    private synchronized native boolean getNextFile(Object[] parts);

    private synchronized native ByteBuffer getUnusedInput();

    // Resets the engine and frees all resources.

    // Returns total number of bytes consumed by the engine.

    private synchronized native long finish();

    // Setting state in the unpacker.

    protected  synchronized native boolean setOption(String opt, String value);

    protected  synchronized native String getOption(String opt);

    private  int _verbose;

    // State for progress bar:

    private  long _byteCount;      // bytes read in current segment

    private  int  _segCount;       // number of segs scanned

    private  int  _fileCount;      // number of files written

    private  long _estByteLimit;   // estimate of eventual total

    private  int  _estSegLimit;    // ditto

    private  int  _estFileLimit;   // ditto

    private  int  _prevPercent = -1; // for monotonicity

    private final CRC32   _crc32 = new CRC32();

    private       byte[]  _buf   = new byte[1<<14];

    private  UnpackerImpl _p200;

    private  PropMap _props;

    static {

        // If loading from stand alone build uncomment this.

        // System.loadLibrary("unpack");

        java.security.AccessController.doPrivileged(

            new java.security.PrivilegedAction<Void>() {

                public Void run() {

                    System.loadLibrary("unpack");

                    return null;

                }

            });

        initIDs();

    }

    NativeUnpack(UnpackerImpl p200) {

        super();

        _p200  = p200;

        _props = p200.props;

        p200._nunp = this;

    }

    // for JNI callbacks

    static private Object currentInstance() {

        UnpackerImpl p200 = (UnpackerImpl) Utils.getTLGlobals();

        return (p200 == null)? null: p200._nunp;

    }

    private synchronized long getUnpackerPtr() {

        return unpackerPtr;

    }

    // Callback from the unpacker engine to get more data.

    private long readInputFn(ByteBuffer pbuf, long minlen) throws IOException {

        if (in == null)  return 0;  // nothing is readable

        long maxlen = pbuf.capacity() - pbuf.position();

        assert(minlen <= maxlen);  // don't talk nonsense

        long numread = 0;

        int steps = 0;

        while (numread < minlen) {

            steps++;

            // read available input, up to buf.length or maxlen

            int readlen = _buf.length;

            if (readlen > (maxlen - numread))

                readlen = (int)(maxlen - numread);

            int nr = in.read(_buf, 0, readlen);

            if (nr <= 0)  break;

            numread += nr;

            assert(numread <= maxlen);

            // %%% get rid of this extra copy by using nio?

            pbuf.put(_buf, 0, nr);

        }

        if (_verbose > 1)

            Utils.log.fine("readInputFn("+minlen+","+maxlen+") => "+numread+" steps="+steps);

        if (maxlen > 100) {

            _estByteLimit = _byteCount + maxlen;

        } else {

            _estByteLimit = (_byteCount + numread) * 20;

        }

        _byteCount += numread;

        updateProgress();

        return numread;

    }

    private void updateProgress() {

        // Progress is a combination of segment reading and file writing.

        final double READ_WT  = 0.33;

        final double WRITE_WT = 0.67;

        double readProgress = _segCount;

        if (_estByteLimit > 0 && _byteCount > 0)

            readProgress += (double)_byteCount / _estByteLimit;

        double writeProgress = _fileCount;

        double scaledProgress

            = READ_WT  * readProgress  / Math.max(_estSegLimit,1)

            + WRITE_WT * writeProgress / Math.max(_estFileLimit,1);

        int percent = (int) Math.round(100*scaledProgress);

        if (percent > 100)  percent = 100;

        if (percent > _prevPercent) {

            _prevPercent = percent;

            _props.setInteger(Pack200.Unpacker.PROGRESS, percent);

            if (_verbose > 0)

                Utils.log.info("progress = "+percent);

        }

    }

    private void copyInOption(String opt) {

        String val = _props.getProperty(opt);

        if (_verbose > 0)

            Utils.log.info("set "+opt+"="+val);

        if (val != null) {

            boolean set = setOption(opt, val);

            if (!set)

                Utils.log.warning("Invalid option "+opt+"="+val);

        }

    }

    void run(InputStream inRaw, JarOutputStream jstream,

             ByteBuffer presetInput) throws IOException {

        BufferedInputStream in0 = new BufferedInputStream(inRaw);

        this.in = in0;    // for readInputFn to see

        _verbose = _props.getInteger(Utils.DEBUG_VERBOSE);

        // Fix for BugId: 4902477, -unpack.modification.time = 1059010598000

        // TODO eliminate and fix in unpack.cpp

        final int modtime = Pack200.Packer.KEEP.equals(_props.getProperty(Utils.UNPACK_MODIFICATION_TIME, "0")) ?

                Constants.NO_MODTIME : _props.getTime(Utils.UNPACK_MODIFICATION_TIME);

        copyInOption(Utils.DEBUG_VERBOSE);

        copyInOption(Pack200.Unpacker.DEFLATE_HINT);

        if (modtime == Constants.NO_MODTIME)  // Don't pass KEEP && NOW

            copyInOption(Utils.UNPACK_MODIFICATION_TIME);

        updateProgress();  // reset progress bar

        for (;;) {

            // Read the packed bits.

            long counts = start(presetInput, 0);

            _byteCount = _estByteLimit = 0;  // reset partial scan counts

            ++_segCount;  // just finished scanning a whole segment...

            int nextSeg  = (int)( counts >>> 32 );

            int nextFile = (int)( counts >>>  0 );

            // Estimate eventual total number of segments and files.

            _estSegLimit = _segCount + nextSeg;

            double filesAfterThisSeg = _fileCount + nextFile;

            _estFileLimit = (int)( (filesAfterThisSeg *

                                    _estSegLimit) / _segCount );

            // Write the files.

            int[] intParts = { 0,0, 0, 0 };

            //    intParts = {size.hi/lo, mod, defl}

            Object[] parts = { intParts, null, null, null };

            //       parts = { {intParts}, name, data0/1 }

            while (getNextFile(parts)) {

                //BandStructure.printArrayTo(System.out, intParts, 0, parts.length);

                String name = (String) parts[1];

                long   size = ( (long)intParts[0] << 32)

                            + (((long)intParts[1] << 32) >>> 32);

                long   mtime = (modtime != Constants.NO_MODTIME ) ?

                                modtime : intParts[2] ;

                boolean deflateHint = (intParts[3] != 0);

                ByteBuffer data0 = (ByteBuffer) parts[2];

                ByteBuffer data1 = (ByteBuffer) parts[3];

                writeEntry(jstream, name, mtime, size, deflateHint,

                           data0, data1);

                ++_fileCount;

                updateProgress();

            }

            presetInput = getUnusedInput();

            long consumed = finish();

            if (_verbose > 0)

                Utils.log.info("bytes consumed = "+consumed);

            if (presetInput == null &&

                !Utils.isPackMagic(Utils.readMagic(in0))) {

                break;

            }

            if (_verbose > 0 ) {

                if (presetInput != null)

                    Utils.log.info("unused input = "+presetInput);

            }

        }

    }

    void run(InputStream in, JarOutputStream jstream) throws IOException {

        run(in, jstream, null);

    }

    void run(File inFile, JarOutputStream jstream) throws IOException {

        // %%% maybe memory-map the file, and pass it straight into unpacker

        ByteBuffer mappedFile = null;

        try (FileInputStream fis = new FileInputStream(inFile)) {

            run(fis, jstream, mappedFile);

        }

        // Note:  caller is responsible to finish with jstream.

    }

    private void writeEntry(JarOutputStream j, String name,

                            long mtime, long lsize, boolean deflateHint,

                            ByteBuffer data0, ByteBuffer data1) throws IOException {

        int size = (int)lsize;

        if (size != lsize)

            throw new IOException("file too large: "+lsize);

        CRC32 crc32 = _crc32;

        if (_verbose > 1)

            Utils.log.fine("Writing entry: "+name+" size="+size

                             +(deflateHint?" deflated":""));

        if (_buf.length < size) {

            int newSize = size;

            while (newSize < _buf.length) {

                newSize <<= 1;

                if (newSize <= 0) {

                    newSize = size;

                    break;

                }

            }

            _buf = new byte[newSize];

        }

        assert(_buf.length >= size);

        int fillp = 0;

        if (data0 != null) {

            int size0 = data0.capacity();

            data0.get(_buf, fillp, size0);

            fillp += size0;

        }

        if (data1 != null) {

            int size1 = data1.capacity();

            data1.get(_buf, fillp, size1);

            fillp += size1;

        }

        while (fillp < size) {

            // Fill in rest of data from the stream itself.

            int nr = in.read(_buf, fillp, size - fillp);

            if (nr <= 0)  throw new IOException("EOF at end of archive");

            fillp += nr;

        }

        ZipEntry z = new ZipEntry(name);

        z.setTime(mtime * 1000);

        if (size == 0) {

            z.setMethod(ZipOutputStream.STORED);

            z.setSize(0);

            z.setCrc(0);

            z.setCompressedSize(0);

        } else if (!deflateHint) {

            z.setMethod(ZipOutputStream.STORED);

            z.setSize(size);

            z.setCompressedSize(size);

            crc32.reset();

            crc32.update(_buf, 0, size);

            z.setCrc(crc32.getValue());

        } else {

            z.setMethod(Deflater.DEFLATED);

            z.setSize(size);

        }

        j.putNextEntry(z);

        if (size > 0)

            j.write(_buf, 0, size);

        j.closeEntry();

        if (_verbose > 0) Utils.log.info("Writing " + Utils.zeString(z));

    }

}