/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
/*
Copyright (c) 2000,2001,2002,2003 ymnk, JCraft,Inc. All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

  1. Redistributions of source code must retain the above copyright notice,
     this list of conditions and the following disclaimer.

  2. Redistributions in binary form must reproduce the above copyright 
     notice, this list of conditions and the following disclaimer in 
     the documentation and/or other materials provided with the distribution.

  3. The names of the authors may not be used to endorse or promote products
     derived from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/*
 * This program is based on zlib-1.1.3, so all credit should go authors
 * Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
 * and contributors of zlib.
 */

package com.jcraft.jzlib;

final class InfTree{

  static final private int MANY=1440;

  static final private int Z_OK=0;
//  static final private int Z_STREAM_END=1;
//  static final private int Z_NEED_DICT=2;
//  static final private int Z_ERRNO=-1;
//  static final private int Z_STREAM_ERROR=-2;
  static final private int Z_DATA_ERROR=-3;
  static final private int Z_MEM_ERROR=-4;
  static final private int Z_BUF_ERROR=-5;
//  static final private int Z_VERSION_ERROR=-6;

  static final int fixed_bl = 9;
  static final int fixed_bd = 5;

  static final int[] fixed_tl = {
    96,7,256, 0,8,80, 0,8,16, 84,8,115,
    82,7,31, 0,8,112, 0,8,48, 0,9,192,
    80,7,10, 0,8,96, 0,8,32, 0,9,160,
    0,8,0, 0,8,128, 0,8,64, 0,9,224,
    80,7,6, 0,8,88, 0,8,24, 0,9,144,
    83,7,59, 0,8,120, 0,8,56, 0,9,208,
    81,7,17, 0,8,104, 0,8,40, 0,9,176,
    0,8,8, 0,8,136, 0,8,72, 0,9,240,
    80,7,4, 0,8,84, 0,8,20, 85,8,227,
    83,7,43, 0,8,116, 0,8,52, 0,9,200,
    81,7,13, 0,8,100, 0,8,36, 0,9,168,
    0,8,4, 0,8,132, 0,8,68, 0,9,232,
    80,7,8, 0,8,92, 0,8,28, 0,9,152,
    84,7,83, 0,8,124, 0,8,60, 0,9,216,
    82,7,23, 0,8,108, 0,8,44, 0,9,184,
    0,8,12, 0,8,140, 0,8,76, 0,9,248,
    80,7,3, 0,8,82, 0,8,18, 85,8,163,
    83,7,35, 0,8,114, 0,8,50, 0,9,196,
    81,7,11, 0,8,98, 0,8,34, 0,9,164,
    0,8,2, 0,8,130, 0,8,66, 0,9,228,
    80,7,7, 0,8,90, 0,8,26, 0,9,148,
    84,7,67, 0,8,122, 0,8,58, 0,9,212,
    82,7,19, 0,8,106, 0,8,42, 0,9,180,
    0,8,10, 0,8,138, 0,8,74, 0,9,244,
    80,7,5, 0,8,86, 0,8,22, 192,8,0,
    83,7,51, 0,8,118, 0,8,54, 0,9,204,
    81,7,15, 0,8,102, 0,8,38, 0,9,172,
    0,8,6, 0,8,134, 0,8,70, 0,9,236,
    80,7,9, 0,8,94, 0,8,30, 0,9,156,
    84,7,99, 0,8,126, 0,8,62, 0,9,220,
    82,7,27, 0,8,110, 0,8,46, 0,9,188,
    0,8,14, 0,8,142, 0,8,78, 0,9,252,
    96,7,256, 0,8,81, 0,8,17, 85,8,131,
    82,7,31, 0,8,113, 0,8,49, 0,9,194,
    80,7,10, 0,8,97, 0,8,33, 0,9,162,
    0,8,1, 0,8,129, 0,8,65, 0,9,226,
    80,7,6, 0,8,89, 0,8,25, 0,9,146,
    83,7,59, 0,8,121, 0,8,57, 0,9,210,
    81,7,17, 0,8,105, 0,8,41, 0,9,178,
    0,8,9, 0,8,137, 0,8,73, 0,9,242,
    80,7,4, 0,8,85, 0,8,21, 80,8,258,
    83,7,43, 0,8,117, 0,8,53, 0,9,202,
    81,7,13, 0,8,101, 0,8,37, 0,9,170,
    0,8,5, 0,8,133, 0,8,69, 0,9,234,
    80,7,8, 0,8,93, 0,8,29, 0,9,154,
    84,7,83, 0,8,125, 0,8,61, 0,9,218,
    82,7,23, 0,8,109, 0,8,45, 0,9,186,
    0,8,13, 0,8,141, 0,8,77, 0,9,250,
    80,7,3, 0,8,83, 0,8,19, 85,8,195,
    83,7,35, 0,8,115, 0,8,51, 0,9,198,
    81,7,11, 0,8,99, 0,8,35, 0,9,166,
    0,8,3, 0,8,131, 0,8,67, 0,9,230,
    80,7,7, 0,8,91, 0,8,27, 0,9,150,
    84,7,67, 0,8,123, 0,8,59, 0,9,214,
    82,7,19, 0,8,107, 0,8,43, 0,9,182,
    0,8,11, 0,8,139, 0,8,75, 0,9,246,
    80,7,5, 0,8,87, 0,8,23, 192,8,0,
    83,7,51, 0,8,119, 0,8,55, 0,9,206,
    81,7,15, 0,8,103, 0,8,39, 0,9,174,
    0,8,7, 0,8,135, 0,8,71, 0,9,238,
    80,7,9, 0,8,95, 0,8,31, 0,9,158,
    84,7,99, 0,8,127, 0,8,63, 0,9,222,
    82,7,27, 0,8,111, 0,8,47, 0,9,190,
    0,8,15, 0,8,143, 0,8,79, 0,9,254,
    96,7,256, 0,8,80, 0,8,16, 84,8,115,
    82,7,31, 0,8,112, 0,8,48, 0,9,193,

    80,7,10, 0,8,96, 0,8,32, 0,9,161,
    0,8,0, 0,8,128, 0,8,64, 0,9,225,
    80,7,6, 0,8,88, 0,8,24, 0,9,145,
    83,7,59, 0,8,120, 0,8,56, 0,9,209,
    81,7,17, 0,8,104, 0,8,40, 0,9,177,
    0,8,8, 0,8,136, 0,8,72, 0,9,241,
    80,7,4, 0,8,84, 0,8,20, 85,8,227,
    83,7,43, 0,8,116, 0,8,52, 0,9,201,
    81,7,13, 0,8,100, 0,8,36, 0,9,169,
    0,8,4, 0,8,132, 0,8,68, 0,9,233,
    80,7,8, 0,8,92, 0,8,28, 0,9,153,
    84,7,83, 0,8,124, 0,8,60, 0,9,217,
    82,7,23, 0,8,108, 0,8,44, 0,9,185,
    0,8,12, 0,8,140, 0,8,76, 0,9,249,
    80,7,3, 0,8,82, 0,8,18, 85,8,163,
    83,7,35, 0,8,114, 0,8,50, 0,9,197,
    81,7,11, 0,8,98, 0,8,34, 0,9,165,
    0,8,2, 0,8,130, 0,8,66, 0,9,229,
    80,7,7, 0,8,90, 0,8,26, 0,9,149,
    84,7,67, 0,8,122, 0,8,58, 0,9,213,
    82,7,19, 0,8,106, 0,8,42, 0,9,181,
    0,8,10, 0,8,138, 0,8,74, 0,9,245,
    80,7,5, 0,8,86, 0,8,22, 192,8,0,
    83,7,51, 0,8,118, 0,8,54, 0,9,205,
    81,7,15, 0,8,102, 0,8,38, 0,9,173,
    0,8,6, 0,8,134, 0,8,70, 0,9,237,
    80,7,9, 0,8,94, 0,8,30, 0,9,157,
    84,7,99, 0,8,126, 0,8,62, 0,9,221,
    82,7,27, 0,8,110, 0,8,46, 0,9,189,
    0,8,14, 0,8,142, 0,8,78, 0,9,253,
    96,7,256, 0,8,81, 0,8,17, 85,8,131,
    82,7,31, 0,8,113, 0,8,49, 0,9,195,
    80,7,10, 0,8,97, 0,8,33, 0,9,163,
    0,8,1, 0,8,129, 0,8,65, 0,9,227,
    80,7,6, 0,8,89, 0,8,25, 0,9,147,
    83,7,59, 0,8,121, 0,8,57, 0,9,211,
    81,7,17, 0,8,105, 0,8,41, 0,9,179,
    0,8,9, 0,8,137, 0,8,73, 0,9,243,
    80,7,4, 0,8,85, 0,8,21, 80,8,258,
    83,7,43, 0,8,117, 0,8,53, 0,9,203,
    81,7,13, 0,8,101, 0,8,37, 0,9,171,
    0,8,5, 0,8,133, 0,8,69, 0,9,235,
    80,7,8, 0,8,93, 0,8,29, 0,9,155,
    84,7,83, 0,8,125, 0,8,61, 0,9,219,
    82,7,23, 0,8,109, 0,8,45, 0,9,187,
    0,8,13, 0,8,141, 0,8,77, 0,9,251,
    80,7,3, 0,8,83, 0,8,19, 85,8,195,
    83,7,35, 0,8,115, 0,8,51, 0,9,199,
    81,7,11, 0,8,99, 0,8,35, 0,9,167,
    0,8,3, 0,8,131, 0,8,67, 0,9,231,
    80,7,7, 0,8,91, 0,8,27, 0,9,151,
    84,7,67, 0,8,123, 0,8,59, 0,9,215,
    82,7,19, 0,8,107, 0,8,43, 0,9,183,
    0,8,11, 0,8,139, 0,8,75, 0,9,247,
    80,7,5, 0,8,87, 0,8,23, 192,8,0,
    83,7,51, 0,8,119, 0,8,55, 0,9,207,
    81,7,15, 0,8,103, 0,8,39, 0,9,175,
    0,8,7, 0,8,135, 0,8,71, 0,9,239,
    80,7,9, 0,8,95, 0,8,31, 0,9,159,
    84,7,99, 0,8,127, 0,8,63, 0,9,223,
    82,7,27, 0,8,111, 0,8,47, 0,9,191,
    0,8,15, 0,8,143, 0,8,79, 0,9,255
  };
  static final int[] fixed_td = {
    80,5,1, 87,5,257, 83,5,17, 91,5,4097,
    81,5,5, 89,5,1025, 85,5,65, 93,5,16385,
    80,5,3, 88,5,513, 84,5,33, 92,5,8193,
    82,5,9, 90,5,2049, 86,5,129, 192,5,24577,
    80,5,2, 87,5,385, 83,5,25, 91,5,6145,
    81,5,7, 89,5,1537, 85,5,97, 93,5,24577,
    80,5,4, 88,5,769, 84,5,49, 92,5,12289,
    82,5,13, 90,5,3073, 86,5,193, 192,5,24577
  };

  // Tables for deflate from PKZIP's appnote.txt.
  static final int[] cplens = { // Copy lengths for literal codes 257..285
        3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 15, 17, 19, 23, 27, 31,
        35, 43, 51, 59, 67, 83, 99, 115, 131, 163, 195, 227, 258, 0, 0
  };

  // see note #13 above about 258
  static final int[] cplext = { // Extra bits for literal codes 257..285
        0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2, 2,
        3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0, 112, 112  // 112==invalid
  };

  static final int[] cpdist = { // Copy offsets for distance codes 0..29
        1, 2, 3, 4, 5, 7, 9, 13, 17, 25, 33, 49, 65, 97, 129, 193,
        257, 385, 513, 769, 1025, 1537, 2049, 3073, 4097, 6145,
        8193, 12289, 16385, 24577
  };

  static final int[] cpdext = { // Extra bits for distance codes
        0, 0, 0, 0, 1, 1, 2, 2, 3, 3, 4, 4, 5, 5, 6, 6,
        7, 7, 8, 8, 9, 9, 10, 10, 11, 11,
        12, 12, 13, 13};

  // If BMAX needs to be larger than 16, then h and x[] should be uLong.
  static final int BMAX=15;         // maximum bit length of any code

  int[] hn = null;  // hufts used in space
  int[] v = null;   // work area for huft_build 
  int[] c = null;   // bit length count table
  int[] r = null;   // table entry for structure assignment
  int[] u = null;   // table stack
  int[] x = null;   // bit offsets, then code stack

  private int huft_build(int[] b, // code lengths in bits (all assumed <= BMAX)
                         int bindex, 
                         int n,   // number of codes (assumed <= 288)
                         int s,   // number of simple-valued codes (0..s-1)
                         int[] d, // list of base values for non-simple codes
                         int[] e, // list of extra bits for non-simple codes
                         int[] t, // result: starting table
                         int[] m, // maximum lookup bits, returns actual
                         int[] hp,// space for trees
                         int[] hn,// hufts used in space
                         int[] v  // working area: values in order of bit length
                         ){
    // Given a list of code lengths and a maximum table size, make a set of
    // tables to decode that set of codes.  Return Z_OK on success, Z_BUF_ERROR
    // if the given code set is incomplete (the tables are still built in this
    // case), Z_DATA_ERROR if the input is invalid (an over-subscribed set of
    // lengths), or Z_MEM_ERROR if not enough memory.

    int a;                       // counter for codes of length k
    int f;                       // i repeats in table every f entries
    int g;                       // maximum code length
    int h;                       // table level
    int i;                       // counter, current code
    int j;                       // counter
    int k;                       // number of bits in current code
    int l;                       // bits per table (returned in m)
    int mask;                    // (1 << w) - 1, to avoid cc -O bug on HP
    int p;                       // pointer into c[], b[], or v[]
    int q;                       // points to current table
    int w;                       // bits before this table == (l * h)
    int xp;                      // pointer into x
    int y;                       // number of dummy codes added
    int z;                       // number of entries in current table

    // Generate counts for each bit length

    p = 0; i = n;
    do {
      c[b[bindex+p]]++; p++; i--;   // assume all entries <= BMAX
    }while(i!=0);

    if(c[0] == n){                // null input--all zero length codes
      t[0] = -1;
      m[0] = 0;
      return Z_OK;
    }

    // Find minimum and maximum length, bound *m by those
    l = m[0];
    for (j = 1; j <= BMAX; j++)
      if(c[j]!=0) break;
    k = j;                        // minimum code length
    if(l < j){
      l = j;
    }
    for (i = BMAX; i!=0; i--){
      if(c[i]!=0) break;
    }
    g = i;                        // maximum code length
    if(l > i){
      l = i;
    }
    m[0] = l;

    // Adjust last length count to fill out codes, if needed
    for (y = 1 << j; j < i; j++, y <<= 1){
      if ((y -= c[j]) < 0){
        return Z_DATA_ERROR;
      }
    }
    if ((y -= c[i]) < 0){
      return Z_DATA_ERROR;
    }
    c[i] += y;

    // Generate starting offsets into the value table for each length
    x[1] = j = 0;
    p = 1;  xp = 2;
    while (--i!=0) {                 // note that i == g from above
      x[xp] = (j += c[p]);
      xp++;
      p++;
    }

    // Make a table of values in order of bit lengths
    i = 0; p = 0;
    do {
      if ((j = b[bindex+p]) != 0){
        v[x[j]++] = i;
      }
      p++;
    }
    while (++i < n);
    n = x[g];                     // set n to length of v

    // Generate the Huffman codes and for each, make the table entries
    x[0] = i = 0;                 // first Huffman code is zero
    p = 0;                        // grab values in bit order
    h = -1;                       // no tables yet--level -1
    w = -l;                       // bits decoded == (l * h)
    u[0] = 0;                     // just to keep compilers happy
    q = 0;                        // ditto
    z = 0;                        // ditto

    // go through the bit lengths (k already is bits in shortest code)
    for (; k <= g; k++){
      a = c[k];
      while (a--!=0){
	// here i is the Huffman code of length k bits for value *p
	// make tables up to required level
        while (k > w + l){
          h++;
          w += l;                 // previous table always l bits
	  // compute minimum size table less than or equal to l bits
          z = g - w;
          z = (z > l) ? l : z;        // table size upper limit
          if((f=1<<(j=k-w))>a+1){     // try a k-w bit table
                                      // too few codes for k-w bit table
            f -= a + 1;               // deduct codes from patterns left
            xp = k;
            if(j < z){
              while (++j < z){        // try smaller tables up to z bits
                if((f <<= 1) <= c[++xp])
                  break;              // enough codes to use up j bits
                f -= c[xp];           // else deduct codes from patterns
              }
	    }
          }
          z = 1 << j;                 // table entries for j-bit table

	  // allocate new table
          if (hn[0] + z > MANY){       // (note: doesn't matter for fixed)
            return Z_DATA_ERROR;       // overflow of MANY
          }
          u[h] = q = /*hp+*/ hn[0];   // DEBUG
          hn[0] += z;
 
	  // connect to last table, if there is one
	  if(h!=0){
            x[h]=i;           // save pattern for backing up
            r[0]=(byte)j;     // bits in this table
            r[1]=(byte)l;     // bits to dump before this table
            j=i>>>(w - l);
            r[2] = (q - u[h-1] - j);               // offset to this table
            System.arraycopy(r, 0, hp, (u[h-1]+j)*3, 3); // connect to last table
          }
          else{
            t[0] = q;               // first table is returned result
	  }
        }

	// set up table entry in r
        r[1] = (byte)(k - w);
        if (p >= n){
          r[0] = 128 + 64;      // out of values--invalid code
	}
        else if (v[p] < s){
          r[0] = (byte)(v[p] < 256 ? 0 : 32 + 64);  // 256 is end-of-block
          r[2] = v[p++];          // simple code is just the value
        }
        else{
          r[0]=(byte)(e[v[p]-s]+16+64); // non-simple--look up in lists
          r[2]=d[v[p++] - s];
        }

        // fill code-like entries with r
        f=1<<(k-w);
        for (j=i>>>w;j<z;j+=f){
          System.arraycopy(r, 0, hp, (q+j)*3, 3);
	}

	// backwards increment the k-bit code i
        for (j = 1 << (k - 1); (i & j)!=0; j >>>= 1){
          i ^= j;
	}
        i ^= j;

	// backup over finished tables
        mask = (1 << w) - 1;      // needed on HP, cc -O bug
        while ((i & mask) != x[h]){
          h--;                    // don't need to update q
          w -= l;
          mask = (1 << w) - 1;
        }
      }
    }
    // Return Z_BUF_ERROR if we were given an incomplete table
    return y != 0 && g != 1 ? Z_BUF_ERROR : Z_OK;
  }

  int inflate_trees_bits(int[] c,  // 19 code lengths
                         int[] bb, // bits tree desired/actual depth
                         int[] tb, // bits tree result
                         int[] hp, // space for trees
                         ZStream z // for messages
                         ){
    int result;
    initWorkArea(19);
    hn[0]=0;
    result = huft_build(c, 0, 19, 19, null, null, tb, bb, hp, hn, v);

    if(result == Z_DATA_ERROR){
      z.msg = "oversubscribed dynamic bit lengths tree";
    }
    else if(result == Z_BUF_ERROR || bb[0] == 0){
      z.msg = "incomplete dynamic bit lengths tree";
      result = Z_DATA_ERROR;
    }
    return result;
  }

  int inflate_trees_dynamic(int nl,   // number of literal/length codes
                            int nd,   // number of distance codes
                            int[] c,  // that many (total) code lengths
                            int[] bl, // literal desired/actual bit depth
                            int[] bd, // distance desired/actual bit depth 
                            int[] tl, // literal/length tree result
                            int[] td, // distance tree result
                            int[] hp, // space for trees
                            ZStream z // for messages
                            ){
    int result;

    // build literal/length tree
    initWorkArea(288);
    hn[0]=0;
    result = huft_build(c, 0, nl, 257, cplens, cplext, tl, bl, hp, hn, v);
    if (result != Z_OK || bl[0] == 0){
      if(result == Z_DATA_ERROR){
        z.msg = "oversubscribed literal/length tree";
      }
      else if (result != Z_MEM_ERROR){
        z.msg = "incomplete literal/length tree";
        result = Z_DATA_ERROR;
      }
      return result;
    }

    // build distance tree
    initWorkArea(288);
    result = huft_build(c, nl, nd, 0, cpdist, cpdext, td, bd, hp, hn, v);

    if (result != Z_OK || (bd[0] == 0 && nl > 257)){
      if (result == Z_DATA_ERROR){
        z.msg = "oversubscribed distance tree";
      }
      else if (result == Z_BUF_ERROR) {
        z.msg = "incomplete distance tree";
        result = Z_DATA_ERROR;
      }
      else if (result != Z_MEM_ERROR){
        z.msg = "empty distance tree with lengths";
        result = Z_DATA_ERROR;
      }
      return result;
    }

    return Z_OK;
  }

  /**
   * @param bl 
   * @param bd 
   * @param tl 
   * @param td 
   * @param z  
   * @return Z_OK
   */
  static int inflate_trees_fixed(int[] bl,  //literal desired/actual bit depth
                                 int[] bd,  //distance desired/actual bit depth
                                 int[][] tl,//literal/length tree result
                                 int[][] td,//distance tree result 
                                 ZStream z  //for memory allocation
				 ){
    bl[0]=fixed_bl;
    bd[0]=fixed_bd;
    tl[0]=fixed_tl;
    td[0]=fixed_td;
    return Z_OK;
  }

  private void initWorkArea(int vsize){
    if(hn==null){
      hn=new int[1];
      v=new int[vsize];
      c=new int[BMAX+1];
      r=new int[3];
      u=new int[BMAX];
      x=new int[BMAX+1];
    }
    if(v.length<vsize){ v=new int[vsize]; }
    for(int i=0; i<vsize; i++){v[i]=0;}
    for(int i=0; i<BMAX+1; i++){c[i]=0;}
    for(int i=0; i<3; i++){r[i]=0;}
    System.arraycopy(c, 0, u, 0, BMAX);
    System.arraycopy(c, 0, x, 0, BMAX+1);
  }
}
