content: /*
   * Copyright (c) 2009, 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.
   */
  
  package com.itsaky.androidide.zipfs2;
  
  import java.nio.ByteBuffer;
  import java.nio.CharBuffer;
  import java.nio.charset.Charset;
  import java.nio.charset.CharsetDecoder;
  import java.nio.charset.CharsetEncoder;
  import java.nio.charset.CoderResult;
  import java.nio.charset.CodingErrorAction;
  import java.util.Arrays;
  
  import static java.nio.charset.StandardCharsets.ISO_8859_1;
  import static java.nio.charset.StandardCharsets.UTF_8;
  
  /**
   * Utility class for zipfile name and comment decoding and encoding
   *
   * @author Xueming Shen
   */
  public class ZipCoder {
  
      static class UTF8 extends ZipCoder {
          UTF8() {
              super(UTF_8);
          }
  
          @Override
          byte[] getBytes(String s) {        // fast pass for ascii
              for (int i = 0; i < s.length(); i++) {
                  if (s.charAt(i) > 0x7f) return super.getBytes(s);
              }
              return s.getBytes(ISO_8859_1);
          }
  
          @Override
          String toString(byte[] ba) {
              for (byte b : ba) {
                  if (b < 0) return super.toString(ba);
              }
              return new String(ba, ISO_8859_1);
          }
      }
  
      private static final ZipCoder utf8 = new UTF8();
  
      public static ZipCoder get(String csn) {
          Charset cs = Charset.forName(csn);
          if (cs.name().equals("UTF-8")) {
              return utf8;
          }
          return new ZipCoder(cs);
      }
  
      String toString(byte[] ba) {
          CharsetDecoder cd = decoder().reset();
          int clen = (int)(ba.length * cd.maxCharsPerByte());
          char[] ca = new char[clen];
          if (clen == 0)
              return new String(ca);
          ByteBuffer bb = ByteBuffer.wrap(ba, 0, ba.length);
          CharBuffer cb = CharBuffer.wrap(ca);
          CoderResult cr = cd.decode(bb, cb, true);
          if (!cr.isUnderflow())
              throw new IllegalArgumentException(cr.toString());
          cr = cd.flush(cb);
          if (!cr.isUnderflow())
              throw new IllegalArgumentException(cr.toString());
          return new String(ca, 0, cb.position());
      }
  
      byte[] getBytes(String s) {
          CharsetEncoder ce = encoder().reset();
          char[] ca = s.toCharArray();
          int len = (int)(ca.length * ce.maxBytesPerChar());
          byte[] ba = new byte[len];
          if (len == 0)
              return ba;
          ByteBuffer bb = ByteBuffer.wrap(ba);
          CharBuffer cb = CharBuffer.wrap(ca);
          CoderResult cr = ce.encode(cb, bb, true);
          if (!cr.isUnderflow())
              throw new IllegalArgumentException(cr.toString());
          cr = ce.flush(bb);
          if (!cr.isUnderflow())
              throw new IllegalArgumentException(cr.toString());
          if (bb.position() == ba.length)  // defensive copy?
              return ba;
          else
              return Arrays.copyOf(ba, bb.position());
      }
  
      boolean isUTF8() {
          return cs == UTF_8;
      }
  
      private Charset cs;
  
      private ZipCoder(Charset cs) {
          this.cs = cs;
      }
  
      private final ThreadLocal<CharsetDecoder> decTL = new ThreadLocal<>();
      private final ThreadLocal<CharsetEncoder> encTL = new ThreadLocal<>();
  
      private CharsetDecoder decoder() {
          CharsetDecoder dec = decTL.get();
          if (dec == null) {
          dec = cs.newDecoder()
              .onMalformedInput(CodingErrorAction.REPORT)
              .onUnmappableCharacter(CodingErrorAction.REPORT);
          decTL.set(dec);
          }
          return dec;
      }
  
      private CharsetEncoder encoder() {
          CharsetEncoder enc = encTL.get();
          if (enc == null) {
          enc = cs.newEncoder()
              .onMalformedInput(CodingErrorAction.REPORT)
              .onUnmappableCharacter(CodingErrorAction.REPORT);
          encTL.set(enc);
          }
          return enc;
      }
  }
  