text: /*
   * $Id: rawdeflate.js,v 0.4 2013/02/23 01:55:59 dankogai Exp dankogai $
   *
   * Original:
   *   http://www.onicos.com/staff/iz/amuse/javascript/expert/deflate.txt
   */
  
  (function(){
  
      /* Copyright (C) 1999 Masanao Izumo <iz@onicos.co.jp>
       * Version: 1.0.1
       * LastModified: Dec 25 1999
       */
      
      /* Interface:
       * data = zip_deflate(src);
       */
      
      /* constant parameters */
      var zip_WSIZE = 32768;		// Sliding Window size
      var zip_STORED_BLOCK = 0;
      var zip_STATIC_TREES = 1;
      var zip_DYN_TREES    = 2;
      
      /* for deflate */
      var zip_DEFAULT_LEVEL = 6;
      var zip_FULL_SEARCH = true;
      var zip_INBUFSIZ = 32768;	// Input buffer size
      var zip_INBUF_EXTRA = 64;	// Extra buffer
      var zip_OUTBUFSIZ = 1024 * 8;
      var zip_window_size = 2 * zip_WSIZE;
      var zip_MIN_MATCH = 3;
      var zip_MAX_MATCH = 258;
      var zip_BITS = 16;
      // for SMALL_MEM
      var zip_LIT_BUFSIZE = 0x2000;
      var zip_HASH_BITS = 13;
      // for MEDIUM_MEM
      // var zip_LIT_BUFSIZE = 0x4000;
      // var zip_HASH_BITS = 14;
      // for BIG_MEM
      // var zip_LIT_BUFSIZE = 0x8000;
      // var zip_HASH_BITS = 15;
      if(zip_LIT_BUFSIZE > zip_INBUFSIZ)
          alert("error: zip_INBUFSIZ is too small");
      if((zip_WSIZE<<1) > (1<<zip_BITS))
          alert("error: zip_WSIZE is too large");
      if(zip_HASH_BITS > zip_BITS-1)
          alert("error: zip_HASH_BITS is too large");
      if(zip_HASH_BITS < 8 || zip_MAX_MATCH != 258)
          alert("error: Code too clever");
      var zip_DIST_BUFSIZE = zip_LIT_BUFSIZE;
      var zip_HASH_SIZE = 1 << zip_HASH_BITS;
      var zip_HASH_MASK = zip_HASH_SIZE - 1;
      var zip_WMASK = zip_WSIZE - 1;
      var zip_NIL = 0; // Tail of hash chains
      var zip_TOO_FAR = 4096;
      var zip_MIN_LOOKAHEAD = zip_MAX_MATCH + zip_MIN_MATCH + 1;
      var zip_MAX_DIST = zip_WSIZE - zip_MIN_LOOKAHEAD;
      var zip_SMALLEST = 1;
      var zip_MAX_BITS = 15;
      var zip_MAX_BL_BITS = 7;
      var zip_LENGTH_CODES = 29;
      var zip_LITERALS =256;
      var zip_END_BLOCK = 256;
      var zip_L_CODES = zip_LITERALS + 1 + zip_LENGTH_CODES;
      var zip_D_CODES = 30;
      var zip_BL_CODES = 19;
      var zip_REP_3_6 = 16;
      var zip_REPZ_3_10 = 17;
      var zip_REPZ_11_138 = 18;
      var zip_HEAP_SIZE = 2 * zip_L_CODES + 1;
      var zip_H_SHIFT = parseInt((zip_HASH_BITS + zip_MIN_MATCH - 1) /
                     zip_MIN_MATCH);
      
      /* variables */
      var zip_free_queue;
      var zip_qhead, zip_qtail;
      var zip_initflag;
      var zip_outbuf = null;
      var zip_outcnt, zip_outoff;
      var zip_complete;
      var zip_window;
      var zip_d_buf;
      var zip_l_buf;
      var zip_prev;
      var zip_bi_buf;
      var zip_bi_valid;
      var zip_block_start;
      var zip_ins_h;
      var zip_hash_head;
      var zip_prev_match;
      var zip_match_available;
      var zip_match_length;
      var zip_prev_length;
      var zip_strstart;
      var zip_match_start;
      var zip_eofile;
      var zip_lookahead;
      var zip_max_chain_length;
      var zip_max_lazy_match;
      var zip_compr_level;
      var zip_good_match;
      var zip_nice_match;
      var zip_dyn_ltree;
      var zip_dyn_dtree;
      var zip_static_ltree;
      var zip_static_dtree;
      var zip_bl_tree;
      var zip_l_desc;
      var zip_d_desc;
      var zip_bl_desc;
      var zip_bl_count;
      var zip_heap;
      var zip_heap_len;
      var zip_heap_max;
      var zip_depth;
      var zip_length_code;
      var zip_dist_code;
      var zip_base_length;
      var zip_base_dist;
      var zip_flag_buf;
      var zip_last_lit;
      var zip_last_dist;
      var zip_last_flags;
      var zip_flags;
      var zip_flag_bit;
      var zip_opt_len;
      var zip_static_len;
      var zip_deflate_data;
      var zip_deflate_pos;
      
      /* objects (deflate) */
      
      var zip_DeflateCT = function() {
          this.fc = 0; // frequency count or bit string
          this.dl = 0; // father node in Huffman tree or length of bit string
      }
      
      var zip_DeflateTreeDesc = function() {
          this.dyn_tree = null;	// the dynamic tree
          this.static_tree = null;	// corresponding static tree or NULL
          this.extra_bits = null;	// extra bits for each code or NULL
          this.extra_base = 0;	// base index for extra_bits
          this.elems = 0;		// max number of elements in the tree
          this.max_length = 0;	// max bit length for the codes
          this.max_code = 0;		// largest code with non zero frequency
      }
      
      /* Values for max_lazy_match, good_match and max_chain_length, depending on
       * the desired pack level (0..9). The values given below have been tuned to
       * exclude worst case performance for pathological files. Better values may be
       * found for specific files.
       */
      var zip_DeflateConfiguration = function(a, b, c, d) {
          this.good_length = a; // reduce lazy search above this match length
          this.max_lazy = b;    // do not perform lazy search above this match length
          this.nice_length = c; // quit search above this match length
          this.max_chain = d;
      }
      
      var zip_DeflateBuffer = function() {
          this.next = null;
          this.len = 0;
          this.ptr = new Array(zip_OUTBUFSIZ);
          this.off = 0;
      }
      
      /* constant tables */
      var zip_extra_lbits = new Array(
          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);
      var zip_extra_dbits = new Array(
          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);
      var zip_extra_blbits = new Array(
          0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,2,3,7);
      var zip_bl_order = new Array(
          16,17,18,0,8,7,9,6,10,5,11,4,12,3,13,2,14,1,15);
      var zip_configuration_table = new Array(
          new zip_DeflateConfiguration(0,    0,   0,    0),
          new zip_DeflateConfiguration(4,    4,   8,    4),
          new zip_DeflateConfiguration(4,    5,  16,    8),
          new zip_DeflateConfiguration(4,    6,  32,   32),
          new zip_DeflateConfiguration(4,    4,  16,   16),
          new zip_DeflateConfiguration(8,   16,  32,   32),
          new zip_DeflateConfiguration(8,   16, 128,  128),
          new zip_DeflateConfiguration(8,   32, 128,  256),
          new zip_DeflateConfiguration(32, 128, 258, 1024),
          new zip_DeflateConfiguration(32, 258, 258, 4096));
      
      
      /* routines (deflate) */
      
      var zip_deflate_start = function(level) {
          var i;
      
          if(!level)
          level = zip_DEFAULT_LEVEL;
          else if(level < 1)
          level = 1;
          else if(level > 9)
          level = 9;
      
          zip_compr_level = level;
          zip_initflag = false;
          zip_eofile = false;
          if(zip_outbuf != null)
          return;
      
          zip_free_queue = zip_qhead = zip_qtail = null;
          zip_outbuf = new Array(zip_OUTBUFSIZ);
          zip_window = new Array(zip_window_size);
          zip_d_buf = new Array(zip_DIST_BUFSIZE);
          zip_l_buf = new Array(zip_INBUFSIZ + zip_INBUF_EXTRA);
          zip_prev = new Array(1 << zip_BITS);
          zip_dyn_ltree = new Array(zip_HEAP_SIZE);
          for(i = 0; i < zip_HEAP_SIZE; i++)
          zip_dyn_ltree[i] = new zip_DeflateCT();
          zip_dyn_dtree = new Array(2*zip_D_CODES+1);
          for(i = 0; i < 2*zip_D_CODES+1; i++)
          zip_dyn_dtree[i] = new zip_DeflateCT();
          zip_static_ltree = new Array(zip_L_CODES+2);
          for(i = 0; i < zip_L_CODES+2; i++)
          zip_static_ltree[i] = new zip_DeflateCT();
          zip_static_dtree = new Array(zip_D_CODES);
          for(i = 0; i < zip_D_CODES; i++)
          zip_static_dtree[i] = new zip_DeflateCT();
          zip_bl_tree = new Array(2*zip_BL_CODES+1);
          for(i = 0; i < 2*zip_BL_CODES+1; i++)
          zip_bl_tree[i] = new zip_DeflateCT();
          zip_l_desc = new zip_DeflateTreeDesc();
          zip_d_desc = new zip_DeflateTreeDesc();
          zip_bl_desc = new zip_DeflateTreeDesc();
          zip_bl_count = new Array(zip_MAX_BITS+1);
          zip_heap = new Array(2*zip_L_CODES+1);
          zip_depth = new Array(2*zip_L_CODES+1);
          zip_length_code = new Array(zip_MAX_MATCH-zip_MIN_MATCH+1);
          zip_dist_code = new Array(512);
          zip_base_length = new Array(zip_LENGTH_CODES);
          zip_base_dist = new Array(zip_D_CODES);
          zip_flag_buf = new Array(parseInt(zip_LIT_BUFSIZE / 8));
      }
      
      var zip_deflate_end = function() {
          zip_free_queue = zip_qhead = zip_qtail = null;
          zip_outbuf = null;
          zip_window = null;
          zip_d_buf = null;
          zip_l_buf = null;
          zip_prev = null;
          zip_dyn_ltree = null;
          zip_dyn_dtree = null;
          zip_static_ltree = null;
          zip_static_dtree = null;
          zip_bl_tree = null;
          zip_l_desc = null;
          zip_d_desc = null;
          zip_bl_desc = null;
          zip_bl_count = null;
          zip_heap = null;
          zip_depth = null;
          zip_length_code = null;
          zip_dist_code = null;
          zip_base_length = null;
          zip_base_dist = null;
          zip_flag_buf = null;
      }
      
      var zip_reuse_queue = function(p) {
          p.next = zip_free_queue;
          zip_free_queue = p;
      }
      
      var zip_new_queue = function() {
          var p;
      
          if(zip_free_queue != null)
          {
          p = zip_free_queue;
          zip_free_queue = zip_free_queue.next;
          }
          else
          p = new zip_DeflateBuffer();
          p.next = null;
          p.len = p.off = 0;
      
          return p;
      }
      
      var zip_head1 = function(i) {
          return zip_prev[zip_WSIZE + i];
      }
      
      var zip_head2 = function(i, val) {
          return zip_prev[zip_WSIZE + i] = val;
      }
      
      /* put_byte is used for the compressed output, put_ubyte for the
       * uncompressed output. However unlzw() uses window for its
       * suffix table instead of its output buffer, so it does not use put_ubyte
       * (to be cleaned up).
       */
      var zip_put_byte = function(c) {
          zip_outbuf[zip_outoff + zip_outcnt++] = c;
          if(zip_outoff + zip_outcnt == zip_OUTBUFSIZ)
          zip_qoutbuf();
      }
      
      /* Output a 16 bit value, lsb first */
      var zip_put_short = function(w) {
          w &= 0xffff;
          if(zip_outoff + zip_outcnt < zip_OUTBUFSIZ - 2) {
          zip_outbuf[zip_outoff + zip_outcnt++] = (w & 0xff);
          zip_outbuf[zip_outoff + zip_outcnt++] = (w >>> 8);
          } else {
          zip_put_byte(w & 0xff);
          zip_put_byte(w >>> 8);
          }
      }
      
      /* ==========================================================================
       * Insert string s in the dictionary and set match_head to the previous head
       * of the hash chain (the most recent string with same hash key). Return
       * the previous length of the hash chain.
       * IN  assertion: all calls to to INSERT_STRING are made with consecutive
       *    input characters and the first MIN_MATCH bytes of s are valid
       *    (except for the last MIN_MATCH-1 bytes of the input file).
       */
      var zip_INSERT_STRING = function() {
          zip_ins_h = ((zip_ins_h << zip_H_SHIFT)
               ^ (zip_window[zip_strstart + zip_MIN_MATCH - 1] & 0xff))
          & zip_HASH_MASK;
          zip_hash_head = zip_head1(zip_ins_h);
          zip_prev[zip_strstart & zip_WMASK] = zip_hash_head;
          zip_head2(zip_ins_h, zip_strstart);
      }
      
      /* Send a code of the given tree. c and tree must not have side effects */
      var zip_SEND_CODE = function(c, tree) {
          zip_send_bits(tree[c].fc, tree[c].dl);
      }
      
      /* Mapping from a distance to a distance code. dist is the distance - 1 and
       * must not have side effects. dist_code[256] and dist_code[257] are never
       * used.
       */
      var zip_D_CODE = function(dist) {
          return (dist < 256 ? zip_dist_code[dist]
              : zip_dist_code[256 + (dist>>7)]) & 0xff;
      }
      
      /* ==========================================================================
       * Compares to subtrees, using the tree depth as tie breaker when
       * the subtrees have equal frequency. This minimizes the worst case length.
       */
      var zip_SMALLER = function(tree, n, m) {
          return tree[n].fc < tree[m].fc ||
            (tree[n].fc == tree[m].fc && zip_depth[n] <= zip_depth[m]);
      }
      
      /* ==========================================================================
       * read string data
       */
      var zip_read_buff = function(buff, offset, n) {
          var i;
          for(i = 0; i < n && zip_deflate_pos < zip_deflate_data.length; i++)
          buff[offset + i] =
              zip_deflate_data.charCodeAt(zip_deflate_pos++) & 0xff;
          return i;
      }
      
      /* ==========================================================================
       * Initialize the "longest match" routines for a new file
       */
      var zip_lm_init = function() {
          var j;
      
          /* Initialize the hash table. */
          for(j = 0; j < zip_HASH_SIZE; j++)
      //	zip_head2(j, zip_NIL);
          zip_prev[zip_WSIZE + j] = 0;
          /* prev will be initialized on the fly */
      
          /* Set the default configuration parameters:
           */
          zip_max_lazy_match = zip_configuration_table[zip_compr_level].max_lazy;
          zip_good_match     = zip_configuration_table[zip_compr_level].good_length;
          if(!zip_FULL_SEARCH)
          zip_nice_match = zip_configuration_table[zip_compr_level].nice_length;
          zip_max_chain_length = zip_configuration_table[zip_compr_level].max_chain;
      
          zip_strstart = 0;
          zip_block_start = 0;
      
          zip_lookahead = zip_read_buff(zip_window, 0, 2 * zip_WSIZE);
          if(zip_lookahead <= 0) {
          zip_eofile = true;
          zip_lookahead = 0;
          return;
          }
          zip_eofile = false;
          /* Make sure that we always have enough lookahead. This is important
           * if input comes from a device such as a tty.
           */
          while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
          zip_fill_window();
      
          /* If lookahead < MIN_MATCH, ins_h is garbage, but this is
           * not important since only literal bytes will be emitted.
           */
          zip_ins_h = 0;
          for(j = 0; j < zip_MIN_MATCH - 1; j++) {
      //      UPDATE_HASH(ins_h, window[j]);
          zip_ins_h = ((zip_ins_h << zip_H_SHIFT) ^ (zip_window[j] & 0xff)) & zip_HASH_MASK;
          }
      }
      
      /* ==========================================================================
       * Set match_start to the longest match starting at the given string and
       * return its length. Matches shorter or equal to prev_length are discarded,
       * in which case the result is equal to prev_length and match_start is
       * garbage.
       * IN assertions: cur_match is the head of the hash chain for the current
       *   string (strstart) and its distance is <= MAX_DIST, and prev_length >= 1
       */
      var zip_longest_match = function(cur_match) {
          var chain_length = zip_max_chain_length; // max hash chain length
          var scanp = zip_strstart; // current string
          var matchp;		// matched string
          var len;		// length of current match
          var best_len = zip_prev_length;	// best match length so far
      
          /* Stop when cur_match becomes <= limit. To simplify the code,
           * we prevent matches with the string of window index 0.
           */
          var limit = (zip_strstart > zip_MAX_DIST ? zip_strstart - zip_MAX_DIST : zip_NIL);
      
          var strendp = zip_strstart + zip_MAX_MATCH;
          var scan_end1 = zip_window[scanp + best_len - 1];
          var scan_end  = zip_window[scanp + best_len];
      
          /* Do not waste too much time if we already have a good match: */
          if(zip_prev_length >= zip_good_match)
          chain_length >>= 2;
      
      //  Assert(encoder->strstart <= window_size-MIN_LOOKAHEAD, "insufficient lookahead");
      
          do {
      //    Assert(cur_match < encoder->strstart, "no future");
          matchp = cur_match;
      
          /* Skip to next match if the match length cannot increase
              * or if the match length is less than 2:
          */
          if(zip_window[matchp + best_len]	!= scan_end  ||
             zip_window[matchp + best_len - 1]	!= scan_end1 ||
             zip_window[matchp]			!= zip_window[scanp] ||
             zip_window[++matchp]			!= zip_window[scanp + 1]) {
              continue;
          }
      
          /* The check at best_len-1 can be removed because it will be made
               * again later. (This heuristic is not always a win.)
               * It is not necessary to compare scan[2] and match[2] since they
               * are always equal when the other bytes match, given that
               * the hash keys are equal and that HASH_BITS >= 8.
               */
          scanp += 2;
          matchp++;
      
          /* We check for insufficient lookahead only every 8th comparison;
               * the 256th check will be made at strstart+258.
               */
          do {
          } while(zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              zip_window[++scanp] == zip_window[++matchp] &&
              scanp < strendp);
      
            len = zip_MAX_MATCH - (strendp - scanp);
            scanp = strendp - zip_MAX_MATCH;
      
            if(len > best_len) {
            zip_match_start = cur_match;
            best_len = len;
            if(zip_FULL_SEARCH) {
                if(len >= zip_MAX_MATCH) break;
            } else {
                if(len >= zip_nice_match) break;
            }
      
            scan_end1  = zip_window[scanp + best_len-1];
            scan_end   = zip_window[scanp + best_len];
            }
          } while((cur_match = zip_prev[cur_match & zip_WMASK]) > limit
              && --chain_length != 0);
      
          return best_len;
      }
      
      /* ==========================================================================
       * Fill the window when the lookahead becomes insufficient.
       * Updates strstart and lookahead, and sets eofile if end of input file.
       * IN assertion: lookahead < MIN_LOOKAHEAD && strstart + lookahead > 0
       * OUT assertions: at least one byte has been read, or eofile is set;
       *    file reads are performed for at least two bytes (required for the
       *    translate_eol option).
       */
      var zip_fill_window = function() {
          var n, m;
      
          // Amount of free space at the end of the window.
          var more = zip_window_size - zip_lookahead - zip_strstart;
      
          /* If the window is almost full and there is insufficient lookahead,
           * move the upper half to the lower one to make room in the upper half.
           */
          if(more == -1) {
          /* Very unlikely, but possible on 16 bit machine if strstart == 0
               * and lookahead == 1 (input done one byte at time)
               */
          more--;
          } else if(zip_strstart >= zip_WSIZE + zip_MAX_DIST) {
          /* By the IN assertion, the window is not empty so we can't confuse
               * more == 0 with more == 64K on a 16 bit machine.
               */
      //	Assert(window_size == (ulg)2*WSIZE, "no sliding with BIG_MEM");
      
      //	System.arraycopy(window, WSIZE, window, 0, WSIZE);
          for(n = 0; n < zip_WSIZE; n++)
              zip_window[n] = zip_window[n + zip_WSIZE];
            
          zip_match_start -= zip_WSIZE;
          zip_strstart    -= zip_WSIZE; /* we now have strstart >= MAX_DIST: */
          zip_block_start -= zip_WSIZE;
      
          for(n = 0; n < zip_HASH_SIZE; n++) {
              m = zip_head1(n);
              zip_head2(n, m >= zip_WSIZE ? m - zip_WSIZE : zip_NIL);
          }
          for(n = 0; n < zip_WSIZE; n++) {
              /* If n is not on any hash chain, prev[n] is garbage but
               * its value will never be used.
               */
              m = zip_prev[n];
              zip_prev[n] = (m >= zip_WSIZE ? m - zip_WSIZE : zip_NIL);
          }
          more += zip_WSIZE;
          }
          // At this point, more >= 2
          if(!zip_eofile) {
          n = zip_read_buff(zip_window, zip_strstart + zip_lookahead, more);
          if(n <= 0)
              zip_eofile = true;
          else
              zip_lookahead += n;
          }
      }
      
      /* ==========================================================================
       * Processes a new input file and return its compressed length. This
       * function does not perform lazy evaluationof matches and inserts
       * new strings in the dictionary only for unmatched strings or for short
       * matches. It is used only for the fast compression options.
       */
      var zip_deflate_fast = function() {
          while(zip_lookahead != 0 && zip_qhead == null) {
          var flush; // set if current block must be flushed
      
          /* Insert the string window[strstart .. strstart+2] in the
           * dictionary, and set hash_head to the head of the hash chain:
           */
          zip_INSERT_STRING();
      
          /* Find the longest match, discarding those <= prev_length.
           * At this point we have always match_length < MIN_MATCH
           */
          if(zip_hash_head != zip_NIL &&
             zip_strstart - zip_hash_head <= zip_MAX_DIST) {
              /* To simplify the code, we prevent matches with the string
               * of window index 0 (in particular we have to avoid a match
               * of the string with itself at the start of the input file).
               */
              zip_match_length = zip_longest_match(zip_hash_head);
              /* longest_match() sets match_start */
              if(zip_match_length > zip_lookahead)
              zip_match_length = zip_lookahead;
          }
          if(zip_match_length >= zip_MIN_MATCH) {
      //	    check_match(strstart, match_start, match_length);
      
              flush = zip_ct_tally(zip_strstart - zip_match_start,
                       zip_match_length - zip_MIN_MATCH);
              zip_lookahead -= zip_match_length;
      
              /* Insert new strings in the hash table only if the match length
               * is not too large. This saves time but degrades compression.
               */
              if(zip_match_length <= zip_max_lazy_match) {
              zip_match_length--; // string at strstart already in hash table
              do {
                  zip_strstart++;
                  zip_INSERT_STRING();
                  /* strstart never exceeds WSIZE-MAX_MATCH, so there are
                   * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
                   * these bytes are garbage, but it does not matter since
                   * the next lookahead bytes will be emitted as literals.
                   */
              } while(--zip_match_length != 0);
              zip_strstart++;
              } else {
              zip_strstart += zip_match_length;
              zip_match_length = 0;
              zip_ins_h = zip_window[zip_strstart] & 0xff;
      //		UPDATE_HASH(ins_h, window[strstart + 1]);
              zip_ins_h = ((zip_ins_h<<zip_H_SHIFT) ^ (zip_window[zip_strstart + 1] & 0xff)) & zip_HASH_MASK;
      
      //#if MIN_MATCH != 3
      //		Call UPDATE_HASH() MIN_MATCH-3 more times
      //#endif
      
              }
          } else {
              /* No match, output a literal byte */
              flush = zip_ct_tally(0, zip_window[zip_strstart] & 0xff);
              zip_lookahead--;
              zip_strstart++;
          }
          if(flush) {
              zip_flush_block(0);
              zip_block_start = zip_strstart;
          }
      
          /* Make sure that we always have enough lookahead, except
           * at the end of the input file. We need MAX_MATCH bytes
           * for the next match, plus MIN_MATCH bytes to insert the
           * string following the next match.
           */
          while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
              zip_fill_window();
          }
      }
      
      var zip_deflate_better = function() {
          /* Process the input block. */
          while(zip_lookahead != 0 && zip_qhead == null) {
          /* Insert the string window[strstart .. strstart+2] in the
           * dictionary, and set hash_head to the head of the hash chain:
           */
          zip_INSERT_STRING();
      
          /* Find the longest match, discarding those <= prev_length.
           */
          zip_prev_length = zip_match_length;
          zip_prev_match = zip_match_start;
          zip_match_length = zip_MIN_MATCH - 1;
      
          if(zip_hash_head != zip_NIL &&
             zip_prev_length < zip_max_lazy_match &&
             zip_strstart - zip_hash_head <= zip_MAX_DIST) {
              /* To simplify the code, we prevent matches with the string
               * of window index 0 (in particular we have to avoid a match
               * of the string with itself at the start of the input file).
               */
              zip_match_length = zip_longest_match(zip_hash_head);
              /* longest_match() sets match_start */
              if(zip_match_length > zip_lookahead)
              zip_match_length = zip_lookahead;
      
              /* Ignore a length 3 match if it is too distant: */
              if(zip_match_length == zip_MIN_MATCH &&
                 zip_strstart - zip_match_start > zip_TOO_FAR) {
              /* If prev_match is also MIN_MATCH, match_start is garbage
               * but we will ignore the current match anyway.
               */
              zip_match_length--;
              }
          }
          /* If there was a match at the previous step and the current
           * match is not better, output the previous match:
           */
          if(zip_prev_length >= zip_MIN_MATCH &&
             zip_match_length <= zip_prev_length) {
              var flush; // set if current block must be flushed
      
      //	    check_match(strstart - 1, prev_match, prev_length);
              flush = zip_ct_tally(zip_strstart - 1 - zip_prev_match,
                       zip_prev_length - zip_MIN_MATCH);
      
              /* Insert in hash table all strings up to the end of the match.
               * strstart-1 and strstart are already inserted.
               */
              zip_lookahead -= zip_prev_length - 1;
              zip_prev_length -= 2;
              do {
              zip_strstart++;
              zip_INSERT_STRING();
              /* strstart never exceeds WSIZE-MAX_MATCH, so there are
               * always MIN_MATCH bytes ahead. If lookahead < MIN_MATCH
               * these bytes are garbage, but it does not matter since the
               * next lookahead bytes will always be emitted as literals.
               */
              } while(--zip_prev_length != 0);
              zip_match_available = 0;
              zip_match_length = zip_MIN_MATCH - 1;
              zip_strstart++;
              if(flush) {
              zip_flush_block(0);
              zip_block_start = zip_strstart;
              }
          } else if(zip_match_available != 0) {
              /* If there was no match at the previous position, output a
               * single literal. If there was a match but the current match
               * is longer, truncate the previous match to a single literal.
               */
              if(zip_ct_tally(0, zip_window[zip_strstart - 1] & 0xff)) {
              zip_flush_block(0);
              zip_block_start = zip_strstart;
              }
              zip_strstart++;
              zip_lookahead--;
          } else {
              /* There is no previous match to compare with, wait for
               * the next step to decide.
               */
              zip_match_available = 1;
              zip_strstart++;
              zip_lookahead--;
          }
      
          /* Make sure that we always have enough lookahead, except
           * at the end of the input file. We need MAX_MATCH bytes
           * for the next match, plus MIN_MATCH bytes to insert the
           * string following the next match.
           */
          while(zip_lookahead < zip_MIN_LOOKAHEAD && !zip_eofile)
              zip_fill_window();
          }
      }
      
      var zip_init_deflate = function() {
          if(zip_eofile)
          return;
          zip_bi_buf = 0;
          zip_bi_valid = 0;
          zip_ct_init();
          zip_lm_init();
      
          zip_qhead = null;
          zip_outcnt = 0;
          zip_outoff = 0;
          zip_match_available = 0;
      
          if(zip_compr_level <= 3)
          {
          zip_prev_length = zip_MIN_MATCH - 1;
          zip_match_length = 0;
          }
          else
          {
          zip_match_length = zip_MIN_MATCH - 1;
          zip_match_available = 0;
              zip_match_available = 0;
          }
      
          zip_complete = false;
      }
      
      /* ==========================================================================
       * Same as above, but achieves better compression. We use a lazy
       * evaluation for matches: a match is finally adopted only if there is
       * no better match at the next window position.
       */
      var zip_deflate_internal = function(buff, off, buff_size) {
          var n;
      
          if(!zip_initflag)
          {
          zip_init_deflate();
          zip_initflag = true;
          if(zip_lookahead == 0) { // empty
              zip_complete = true;
              return 0;
          }
          }
      
          if((n = zip_qcopy(buff, off, buff_size)) == buff_size)
          return buff_size;
      
          if(zip_complete)
          return n;
      
          if(zip_compr_level <= 3) // optimized for speed
          zip_deflate_fast();
          else
          zip_deflate_better();
          if(zip_lookahead == 0) {
          if(zip_match_available != 0)
              zip_ct_tally(0, zip_window[zip_strstart - 1] & 0xff);
          zip_flush_block(1);
          zip_complete = true;
          }
          return n + zip_qcopy(buff, n + off, buff_size - n);
      }
      
      var zip_qcopy = function(buff, off, buff_size) {
          var n, i, j;
      
          n = 0;
          while(zip_qhead != null && n < buff_size)
          {
          i = buff_size - n;
          if(i > zip_qhead.len)
              i = zip_qhead.len;
      //      System.arraycopy(qhead.ptr, qhead.off, buff, off + n, i);
          for(j = 0; j < i; j++)
              buff[off + n + j] = zip_qhead.ptr[zip_qhead.off + j];
          
          zip_qhead.off += i;
          zip_qhead.len -= i;
          n += i;
          if(zip_qhead.len == 0) {
              var p;
              p = zip_qhead;
              zip_qhead = zip_qhead.next;
              zip_reuse_queue(p);
          }
          }
      
          if(n == buff_size)
          return n;
      
          if(zip_outoff < zip_outcnt) {
          i = buff_size - n;
          if(i > zip_outcnt - zip_outoff)
              i = zip_outcnt - zip_outoff;
          // System.arraycopy(outbuf, outoff, buff, off + n, i);
          for(j = 0; j < i; j++)
              buff[off + n + j] = zip_outbuf[zip_outoff + j];
          zip_outoff += i;
          n += i;
          if(zip_outcnt == zip_outoff)
              zip_outcnt = zip_outoff = 0;
          }
          return n;
      }
      
      /* ==========================================================================
       * Allocate the match buffer, initialize the various tables and save the
       * location of the internal file attribute (ascii/binary) and method
       * (DEFLATE/STORE).
       */
      var zip_ct_init = function() {
          var n;	// iterates over tree elements
          var bits;	// bit counter
          var length;	// length value
          var code;	// code value
          var dist;	// distance index
      
          if(zip_static_dtree[0].dl != 0) return; // ct_init already called
      
          zip_l_desc.dyn_tree		= zip_dyn_ltree;
          zip_l_desc.static_tree	= zip_static_ltree;
          zip_l_desc.extra_bits	= zip_extra_lbits;
          zip_l_desc.extra_base	= zip_LITERALS + 1;
          zip_l_desc.elems		= zip_L_CODES;
          zip_l_desc.max_length	= zip_MAX_BITS;
          zip_l_desc.max_code		= 0;
      
          zip_d_desc.dyn_tree		= zip_dyn_dtree;
          zip_d_desc.static_tree	= zip_static_dtree;
          zip_d_desc.extra_bits	= zip_extra_dbits;
          zip_d_desc.extra_base	= 0;
          zip_d_desc.elems		= zip_D_CODES;
          zip_d_desc.max_length	= zip_MAX_BITS;
          zip_d_desc.max_code		= 0;
      
          zip_bl_desc.dyn_tree	= zip_bl_tree;
          zip_bl_desc.static_tree	= null;
          zip_bl_desc.extra_bits	= zip_extra_blbits;
          zip_bl_desc.extra_base	= 0;
          zip_bl_desc.elems		= zip_BL_CODES;
          zip_bl_desc.max_length	= zip_MAX_BL_BITS;
          zip_bl_desc.max_code	= 0;
      
          // Initialize the mapping length (0..255) -> length code (0..28)
          length = 0;
          for(code = 0; code < zip_LENGTH_CODES-1; code++) {
          zip_base_length[code] = length;
          for(n = 0; n < (1<<zip_extra_lbits[code]); n++)
              zip_length_code[length++] = code;
          }
          // Assert (length == 256, "ct_init: length != 256");
      
          /* Note that the length 255 (match length 258) can be represented
           * in two different ways: code 284 + 5 bits or code 285, so we
           * overwrite length_code[255] to use the best encoding:
           */
          zip_length_code[length-1] = code;
      
          /* Initialize the mapping dist (0..32K) -> dist code (0..29) */
          dist = 0;
          for(code = 0 ; code < 16; code++) {
          zip_base_dist[code] = dist;
          for(n = 0; n < (1<<zip_extra_dbits[code]); n++) {
              zip_dist_code[dist++] = code;
          }
          }
          // Assert (dist == 256, "ct_init: dist != 256");
          dist >>= 7; // from now on, all distances are divided by 128
          for( ; code < zip_D_CODES; code++) {
          zip_base_dist[code] = dist << 7;
          for(n = 0; n < (1<<(zip_extra_dbits[code]-7)); n++)
              zip_dist_code[256 + dist++] = code;
          }
          // Assert (dist == 256, "ct_init: 256+dist != 512");
      
          // Construct the codes of the static literal tree
          for(bits = 0; bits <= zip_MAX_BITS; bits++)
          zip_bl_count[bits] = 0;
          n = 0;
          while(n <= 143) { zip_static_ltree[n++].dl = 8; zip_bl_count[8]++; }
          while(n <= 255) { zip_static_ltree[n++].dl = 9; zip_bl_count[9]++; }
          while(n <= 279) { zip_static_ltree[n++].dl = 7; zip_bl_count[7]++; }
          while(n <= 287) { zip_static_ltree[n++].dl = 8; zip_bl_count[8]++; }
          /* Codes 286 and 287 do not exist, but we must include them in the
           * tree construction to get a canonical Huffman tree (longest code
           * all ones)
           */
          zip_gen_codes(zip_static_ltree, zip_L_CODES + 1);
      
          /* The static distance tree is trivial: */
          for(n = 0; n < zip_D_CODES; n++) {
          zip_static_dtree[n].dl = 5;
          zip_static_dtree[n].fc = zip_bi_reverse(n, 5);
          }
      
          // Initialize the first block of the first file:
          zip_init_block();
      }
      
      /* ==========================================================================
       * Initialize a new block.
       */
      var zip_init_block = function() {
          var n; // iterates over tree elements
      
          // Initialize the trees.
          for(n = 0; n < zip_L_CODES;  n++) zip_dyn_ltree[n].fc = 0;
          for(n = 0; n < zip_D_CODES;  n++) zip_dyn_dtree[n].fc = 0;
          for(n = 0; n < zip_BL_CODES; n++) zip_bl_tree[n].fc = 0;
      
          zip_dyn_ltree[zip_END_BLOCK].fc = 1;
          zip_opt_len = zip_static_len = 0;
          zip_last_lit = zip_last_dist = zip_last_flags = 0;
          zip_flags = 0;
          zip_flag_bit = 1;
      }
      
      /* ==========================================================================
       * Restore the heap property by moving down the tree starting at node k,
       * exchanging a node with the smallest of its two sons if necessary, stopping
       * when the heap property is re-established (each father smaller than its
       * two sons).
       */
      var zip_pqdownheap = function(
          tree,	// the tree to restore
          k) {	// node to move down
          var v = zip_heap[k];
          var j = k << 1;	// left son of k
      
          while(j <= zip_heap_len) {
          // Set j to the smallest of the two sons:
          if(j < zip_heap_len &&
             zip_SMALLER(tree, zip_heap[j + 1], zip_heap[j]))
              j++;
      
          // Exit if v is smaller than both sons
          if(zip_SMALLER(tree, v, zip_heap[j]))
              break;
      
          // Exchange v with the smallest son
          zip_heap[k] = zip_heap[j];
          k = j;
      
          // And continue down the tree, setting j to the left son of k
          j <<= 1;
          }
          zip_heap[k] = v;
      }
      
      /* ==========================================================================
       * Compute the optimal bit lengths for a tree and update the total bit length
       * for the current block.
       * IN assertion: the fields freq and dad are set, heap[heap_max] and
       *    above are the tree nodes sorted by increasing frequency.
       * OUT assertions: the field len is set to the optimal bit length, the
       *     array bl_count contains the frequencies for each bit length.
       *     The length opt_len is updated; static_len is also updated if stree is
       *     not null.
       */
      var zip_gen_bitlen = function(desc) { // the tree descriptor
          var tree		= desc.dyn_tree;
          var extra		= desc.extra_bits;
          var base		= desc.extra_base;
          var max_code	= desc.max_code;
          var max_length	= desc.max_length;
          var stree		= desc.static_tree;
          var h;		// heap index
          var n, m;		// iterate over the tree elements
          var bits;		// bit length
          var xbits;		// extra bits
          var f;		// frequency
          var overflow = 0;	// number of elements with bit length too large
      
          for(bits = 0; bits <= zip_MAX_BITS; bits++)
          zip_bl_count[bits] = 0;
      
          /* In a first pass, compute the optimal bit lengths (which may
           * overflow in the case of the bit length tree).
           */
          tree[zip_heap[zip_heap_max]].dl = 0; // root of the heap
      
          for(h = zip_heap_max + 1; h < zip_HEAP_SIZE; h++) {
          n = zip_heap[h];
          bits = tree[tree[n].dl].dl + 1;
          if(bits > max_length) {
              bits = max_length;
              overflow++;
          }
          tree[n].dl = bits;
          // We overwrite tree[n].dl which is no longer needed
      
          if(n > max_code)
              continue; // not a leaf node
      
          zip_bl_count[bits]++;
          xbits = 0;
          if(n >= base)
              xbits = extra[n - base];
          f = tree[n].fc;
          zip_opt_len += f * (bits + xbits);
          if(stree != null)
              zip_static_len += f * (stree[n].dl + xbits);
          }
          if(overflow == 0)
          return;
      
          // This happens for example on obj2 and pic of the Calgary corpus
      
          // Find the first bit length which could increase:
          do {
          bits = max_length - 1;
          while(zip_bl_count[bits] == 0)
              bits--;
          zip_bl_count[bits]--;		// move one leaf down the tree
          zip_bl_count[bits + 1] += 2;	// move one overflow item as its brother
          zip_bl_count[max_length]--;
          /* The brother of the overflow item also moves one step up,
           * but this does not affect bl_count[max_length]
           */
          overflow -= 2;
          } while(overflow > 0);
      
          /* Now recompute all bit lengths, scanning in increasing frequency.
           * h is still equal to HEAP_SIZE. (It is simpler to reconstruct all
           * lengths instead of fixing only the wrong ones. This idea is taken
           * from 'ar' written by Haruhiko Okumura.)
           */
          for(bits = max_length; bits != 0; bits--) {
          n = zip_bl_count[bits];
          while(n != 0) {
              m = zip_heap[--h];
              if(m > max_code)
              continue;
              if(tree[m].dl != bits) {
              zip_opt_len += (bits - tree[m].dl) * tree[m].fc;
              tree[m].fc = bits;
              }
              n--;
          }
          }
      }
      
        /* ==========================================================================
         * Generate the codes for a given tree and bit counts (which need not be
         * optimal).
         * IN assertion: the array bl_count contains the bit length statistics for
         * the given tree and the field len is set for all tree elements.
         * OUT assertion: the field code is set for all tree elements of non
         *     zero code length.
         */
      var zip_gen_codes = function(tree,	// the tree to decorate
                 max_code) {	// largest code with non zero frequency
          var next_code = new Array(zip_MAX_BITS+1); // next code value for each bit length
          var code = 0;		// running code value
          var bits;			// bit index
          var n;			// code index
      
          /* The distribution counts are first used to generate the code values
           * without bit reversal.
           */
          for(bits = 1; bits <= zip_MAX_BITS; bits++) {
          code = ((code + zip_bl_count[bits-1]) << 1);
          next_code[bits] = code;
          }
      
          /* Check that the bit counts in bl_count are consistent. The last code
           * must be all ones.
           */
      //    Assert (code + encoder->bl_count[MAX_BITS]-1 == (1<<MAX_BITS)-1,
      //	    "inconsistent bit counts");
      //    Tracev((stderr,"\ngen_codes: max_code %d ", max_code));
      
          for(n = 0; n <= max_code; n++) {
          var len = tree[n].dl;
          if(len == 0)
              continue;
          // Now reverse the bits
          tree[n].fc = zip_bi_reverse(next_code[len]++, len);
      
      //      Tracec(tree != static_ltree, (stderr,"\nn %3d %c l %2d c %4x (%x) ",
      //	  n, (isgraph(n) ? n : ' '), len, tree[n].fc, next_code[len]-1));
          }
      }
      
      /* ==========================================================================
       * Construct one Huffman tree and assigns the code bit strings and lengths.
       * Update the total bit length for the current block.
       * IN assertion: the field freq is set for all tree elements.
       * OUT assertions: the fields len and code are set to the optimal bit length
       *     and corresponding code. The length opt_len is updated; static_len is
       *     also updated if stree is not null. The field max_code is set.
       */
      var zip_build_tree = function(desc) { // the tree descriptor
          var tree	= desc.dyn_tree;
          var stree	= desc.static_tree;
          var elems	= desc.elems;
          var n, m;		// iterate over heap elements
          var max_code = -1;	// largest code with non zero frequency
          var node = elems;	// next internal node of the tree
      
          /* Construct the initial heap, with least frequent element in
           * heap[SMALLEST]. The sons of heap[n] are heap[2*n] and heap[2*n+1].
           * heap[0] is not used.
           */
          zip_heap_len = 0;
          zip_heap_max = zip_HEAP_SIZE;
      
          for(n = 0; n < elems; n++) {
          if(tree[n].fc != 0) {
              zip_heap[++zip_heap_len] = max_code = n;
              zip_depth[n] = 0;
          } else
              tree[n].dl = 0;
          }
      
          /* The pkzip format requires that at least one distance code exists,
           * and that at least one bit should be sent even if there is only one
           * possible code. So to avoid special checks later on we force at least
           * two codes of non zero frequency.
           */
          while(zip_heap_len < 2) {
          var xnew = zip_heap[++zip_heap_len] = (max_code < 2 ? ++max_code : 0);
          tree[xnew].fc = 1;
          zip_depth[xnew] = 0;
          zip_opt_len--;
          if(stree != null)
              zip_static_len -= stree[xnew].dl;
          // new is 0 or 1 so it does not have extra bits
          }
          desc.max_code = max_code;
      
          /* The elements heap[heap_len/2+1 .. heap_len] are leaves of the tree,
           * establish sub-heaps of increasing lengths:
           */
          for(n = zip_heap_len >> 1; n >= 1; n--)
          zip_pqdownheap(tree, n);
      
          /* Construct the Huffman tree by repeatedly combining the least two
           * frequent nodes.
           */
          do {
          n = zip_heap[zip_SMALLEST];
          zip_heap[zip_SMALLEST] = zip_heap[zip_heap_len--];
          zip_pqdownheap(tree, zip_SMALLEST);
      
          m = zip_heap[zip_SMALLEST];  // m = node of next least frequency
      
          // keep the nodes sorted by frequency
          zip_heap[--zip_heap_max] = n;
          zip_heap[--zip_heap_max] = m;
      
          // Create a new node father of n and m
          tree[node].fc = tree[n].fc + tree[m].fc;
      //	depth[node] = (char)(MAX(depth[n], depth[m]) + 1);
          if(zip_depth[n] > zip_depth[m] + 1)
              zip_depth[node] = zip_depth[n];
          else
              zip_depth[node] = zip_depth[m] + 1;
          tree[n].dl = tree[m].dl = node;
      
          // and insert the new node in the heap
          zip_heap[zip_SMALLEST] = node++;
          zip_pqdownheap(tree, zip_SMALLEST);
      
          } while(zip_heap_len >= 2);
      
          zip_heap[--zip_heap_max] = zip_heap[zip_SMALLEST];
      
          /* At this point, the fields freq and dad are set. We can now
           * generate the bit lengths.
           */
          zip_gen_bitlen(desc);
      
          // The field len is now set, we can generate the bit codes
          zip_gen_codes(tree, max_code);
      }
      
      /* ==========================================================================
       * Scan a literal or distance tree to determine the frequencies of the codes
       * in the bit length tree. Updates opt_len to take into account the repeat
       * counts. (The contribution of the bit length codes will be added later
       * during the construction of bl_tree.)
       */
      var zip_scan_tree = function(tree,// the tree to be scanned
                     max_code) {  // and its largest code of non zero frequency
          var n;			// iterates over all tree elements
          var prevlen = -1;		// last emitted length
          var curlen;			// length of current code
          var nextlen = tree[0].dl;	// length of next code
          var count = 0;		// repeat count of the current code
          var max_count = 7;		// max repeat count
          var min_count = 4;		// min repeat count
      
          if(nextlen == 0) {
          max_count = 138;
          min_count = 3;
          }
          tree[max_code + 1].dl = 0xffff; // guard
      
          for(n = 0; n <= max_code; n++) {
          curlen = nextlen;
          nextlen = tree[n + 1].dl;
          if(++count < max_count && curlen == nextlen)
              continue;
          else if(count < min_count)
              zip_bl_tree[curlen].fc += count;
          else if(curlen != 0) {
              if(curlen != prevlen)
              zip_bl_tree[curlen].fc++;
              zip_bl_tree[zip_REP_3_6].fc++;
          } else if(count <= 10)
              zip_bl_tree[zip_REPZ_3_10].fc++;
          else
              zip_bl_tree[zip_REPZ_11_138].fc++;
          count = 0; prevlen = curlen;
          if(nextlen == 0) {
              max_count = 138;
              min_count = 3;
          } else if(curlen == nextlen) {
              max_count = 6;
              min_count = 3;
          } else {
              max_count = 7;
              min_count = 4;
          }
          }
      }
      
        /* ==========================================================================
         * Send a literal or distance tree in compressed form, using the codes in
         * bl_tree.
         */
      var zip_send_tree = function(tree, // the tree to be scanned
                 max_code) { // and its largest code of non zero frequency
          var n;			// iterates over all tree elements
          var prevlen = -1;		// last emitted length
          var curlen;			// length of current code
          var nextlen = tree[0].dl;	// length of next code
          var count = 0;		// repeat count of the current code
          var max_count = 7;		// max repeat count
          var min_count = 4;		// min repeat count
      
          /* tree[max_code+1].dl = -1; */  /* guard already set */
          if(nextlen == 0) {
            max_count = 138;
            min_count = 3;
          }
      
          for(n = 0; n <= max_code; n++) {
          curlen = nextlen;
          nextlen = tree[n+1].dl;
          if(++count < max_count && curlen == nextlen) {
              continue;
          } else if(count < min_count) {
              do { zip_SEND_CODE(curlen, zip_bl_tree); } while(--count != 0);
          } else if(curlen != 0) {
              if(curlen != prevlen) {
              zip_SEND_CODE(curlen, zip_bl_tree);
              count--;
              }
              // Assert(count >= 3 && count <= 6, " 3_6?");
              zip_SEND_CODE(zip_REP_3_6, zip_bl_tree);
              zip_send_bits(count - 3, 2);
          } else if(count <= 10) {
              zip_SEND_CODE(zip_REPZ_3_10, zip_bl_tree);
              zip_send_bits(count-3, 3);
          } else {
              zip_SEND_CODE(zip_REPZ_11_138, zip_bl_tree);
              zip_send_bits(count-11, 7);
          }
          count = 0;
          prevlen = curlen;
          if(nextlen == 0) {
              max_count = 138;
              min_count = 3;
          } else if(curlen == nextlen) {
              max_count = 6;
              min_count = 3;
          } else {
              max_count = 7;
              min_count = 4;
          }
          }
      }
      
      /* ==========================================================================
       * Construct the Huffman tree for the bit lengths and return the index in
       * bl_order of the last bit length code to send.
       */
      var zip_build_bl_tree = function() {
          var max_blindex;  // index of last bit length code of non zero freq
      
          // Determine the bit length frequencies for literal and distance trees
          zip_scan_tree(zip_dyn_ltree, zip_l_desc.max_code);
          zip_scan_tree(zip_dyn_dtree, zip_d_desc.max_code);
      
          // Build the bit length tree:
          zip_build_tree(zip_bl_desc);
          /* opt_len now includes the length of the tree representations, except
           * the lengths of the bit lengths codes and the 5+5+4 bits for the counts.
           */
      
          /* Determine the number of bit length codes to send. The pkzip format
           * requires that at least 4 bit length codes be sent. (appnote.txt says
           * 3 but the actual value used is 4.)
           */
          for(max_blindex = zip_BL_CODES-1; max_blindex >= 3; max_blindex--) {
          if(zip_bl_tree[zip_bl_order[max_blindex]].dl != 0) break;
          }
          /* Update opt_len to include the bit length tree and counts */
          zip_opt_len += 3*(max_blindex+1) + 5+5+4;
      //    Tracev((stderr, "\ndyn trees: dyn %ld, stat %ld",
      //	    encoder->opt_len, encoder->static_len));
      
          return max_blindex;
      }
      
      /* ==========================================================================
       * Send the header for a block using dynamic Huffman trees: the counts, the
       * lengths of the bit length codes, the literal tree and the distance tree.
       * IN assertion: lcodes >= 257, dcodes >= 1, blcodes >= 4.
       */
      var zip_send_all_trees = function(lcodes, dcodes, blcodes) { // number of codes for each tree
          var rank; // index in bl_order
      
      //    Assert (lcodes >= 257 && dcodes >= 1 && blcodes >= 4, "not enough codes");
      //    Assert (lcodes <= L_CODES && dcodes <= D_CODES && blcodes <= BL_CODES,
      //	    "too many codes");
      //    Tracev((stderr, "\nbl counts: "));
          zip_send_bits(lcodes-257, 5); // not +255 as stated in appnote.txt
          zip_send_bits(dcodes-1,   5);
          zip_send_bits(blcodes-4,  4); // not -3 as stated in appnote.txt
          for(rank = 0; rank < blcodes; rank++) {
      //      Tracev((stderr, "\nbl code %2d ", bl_order[rank]));
          zip_send_bits(zip_bl_tree[zip_bl_order[rank]].dl, 3);
          }
      
          // send the literal tree
          zip_send_tree(zip_dyn_ltree,lcodes-1);
      
          // send the distance tree
          zip_send_tree(zip_dyn_dtree,dcodes-1);
      }
      
      /* ==========================================================================
       * Determine the best encoding for the current block: dynamic trees, static
       * trees or store, and output the encoded block to the zip file.
       */
      var zip_flush_block = function(eof) { // true if this is the last block for a file
          var opt_lenb, static_lenb; // opt_len and static_len in bytes
          var max_blindex;	// index of last bit length code of non zero freq
          var stored_len;	// length of input block
      
          stored_len = zip_strstart - zip_block_start;
          zip_flag_buf[zip_last_flags] = zip_flags; // Save the flags for the last 8 items
      
          // Construct the literal and distance trees
          zip_build_tree(zip_l_desc);
      //    Tracev((stderr, "\nlit data: dyn %ld, stat %ld",
      //	    encoder->opt_len, encoder->static_len));
      
          zip_build_tree(zip_d_desc);
      //    Tracev((stderr, "\ndist data: dyn %ld, stat %ld",
      //	    encoder->opt_len, encoder->static_len));
          /* At this point, opt_len and static_len are the total bit lengths of
           * the compressed block data, excluding the tree representations.
           */
      
          /* Build the bit length tree for the above two trees, and get the index
           * in bl_order of the last bit length code to send.
           */
          max_blindex = zip_build_bl_tree();
      
          // Determine the best encoding. Compute first the block length in bytes
          opt_lenb	= (zip_opt_len   +3+7)>>3;
          static_lenb = (zip_static_len+3+7)>>3;
      
      //    Trace((stderr, "\nopt %lu(%lu) stat %lu(%lu) stored %lu lit %u dist %u ",
      //	   opt_lenb, encoder->opt_len,
      //	   static_lenb, encoder->static_len, stored_len,
      //	   encoder->last_lit, encoder->last_dist));
      
          if(static_lenb <= opt_lenb)
          opt_lenb = static_lenb;
          if(stored_len + 4 <= opt_lenb // 4: two words for the lengths
             && zip_block_start >= 0) {
          var i;
      
          /* The test buf != NULL is only necessary if LIT_BUFSIZE > WSIZE.
           * Otherwise we can't have processed more than WSIZE input bytes since
           * the last block flush, because compression would have been
           * successful. If LIT_BUFSIZE <= WSIZE, it is never too late to
           * transform a block into a stored block.
           */
          zip_send_bits((zip_STORED_BLOCK<<1)+eof, 3);  /* send block type */
          zip_bi_windup();		 /* align on byte boundary */
          zip_put_short(stored_len);
          zip_put_short(~stored_len);
      
            // copy block
      /*
            p = &window[block_start];
            for(i = 0; i < stored_len; i++)
          put_byte(p[i]);
      */
          for(i = 0; i < stored_len; i++)
              zip_put_byte(zip_window[zip_block_start + i]);
      
          } else if(static_lenb == opt_lenb) {
          zip_send_bits((zip_STATIC_TREES<<1)+eof, 3);
          zip_compress_block(zip_static_ltree, zip_static_dtree);
          } else {
          zip_send_bits((zip_DYN_TREES<<1)+eof, 3);
          zip_send_all_trees(zip_l_desc.max_code+1,
                     zip_d_desc.max_code+1,
                     max_blindex+1);
          zip_compress_block(zip_dyn_ltree, zip_dyn_dtree);
          }
      
          zip_init_block();
      
          if(eof != 0)
          zip_bi_windup();
      }
      
      /* ==========================================================================
       * Save the match info and tally the frequency counts. Return true if
       * the current block must be flushed.
       */
      var zip_ct_tally = function(
          dist, // distance of matched string
          lc) { // match length-MIN_MATCH or unmatched char (if dist==0)
          zip_l_buf[zip_last_lit++] = lc;
          if(dist == 0) {
          // lc is the unmatched char
          zip_dyn_ltree[lc].fc++;
          } else {
          // Here, lc is the match length - MIN_MATCH
          dist--;		    // dist = match distance - 1
      //      Assert((ush)dist < (ush)MAX_DIST &&
      //	     (ush)lc <= (ush)(MAX_MATCH-MIN_MATCH) &&
      //	     (ush)D_CODE(dist) < (ush)D_CODES,  "ct_tally: bad match");
      
          zip_dyn_ltree[zip_length_code[lc]+zip_LITERALS+1].fc++;
          zip_dyn_dtree[zip_D_CODE(dist)].fc++;
      
          zip_d_buf[zip_last_dist++] = dist;
          zip_flags |= zip_flag_bit;
          }
          zip_flag_bit <<= 1;
      
          // Output the flags if they fill a byte
          if((zip_last_lit & 7) == 0) {
          zip_flag_buf[zip_last_flags++] = zip_flags;
          zip_flags = 0;
          zip_flag_bit = 1;
          }
          // Try to guess if it is profitable to stop the current block here
          if(zip_compr_level > 2 && (zip_last_lit & 0xfff) == 0) {
          // Compute an upper bound for the compressed length
          var out_length = zip_last_lit * 8;
          var in_length = zip_strstart - zip_block_start;
          var dcode;
      
          for(dcode = 0; dcode < zip_D_CODES; dcode++) {
              out_length += zip_dyn_dtree[dcode].fc * (5 + zip_extra_dbits[dcode]);
          }
          out_length >>= 3;
      //      Trace((stderr,"\nlast_lit %u, last_dist %u, in %ld, out ~%ld(%ld%%) ",
      //	     encoder->last_lit, encoder->last_dist, in_length, out_length,
      //	     100L - out_length*100L/in_length));
          if(zip_last_dist < parseInt(zip_last_lit/2) &&
             out_length < parseInt(in_length/2))
              return true;
          }
          return (zip_last_lit == zip_LIT_BUFSIZE-1 ||
              zip_last_dist == zip_DIST_BUFSIZE);
          /* We avoid equality with LIT_BUFSIZE because of wraparound at 64K
           * on 16 bit machines and because stored blocks are restricted to
           * 64K-1 bytes.
           */
      }
      
        /* ==========================================================================
         * Send the block data compressed using the given Huffman trees
         */
      var zip_compress_block = function(
          ltree,	// literal tree
          dtree) {	// distance tree
          var dist;		// distance of matched string
          var lc;		// match length or unmatched char (if dist == 0)
          var lx = 0;		// running index in l_buf
          var dx = 0;		// running index in d_buf
          var fx = 0;		// running index in flag_buf
          var flag = 0;	// current flags
          var code;		// the code to send
          var extra;		// number of extra bits to send
      
          if(zip_last_lit != 0) do {
          if((lx & 7) == 0)
              flag = zip_flag_buf[fx++];
          lc = zip_l_buf[lx++] & 0xff;
          if((flag & 1) == 0) {
              zip_SEND_CODE(lc, ltree); /* send a literal byte */
      //	Tracecv(isgraph(lc), (stderr," '%c' ", lc));
          } else {
              // Here, lc is the match length - MIN_MATCH
              code = zip_length_code[lc];
              zip_SEND_CODE(code+zip_LITERALS+1, ltree); // send the length code
              extra = zip_extra_lbits[code];
              if(extra != 0) {
              lc -= zip_base_length[code];
              zip_send_bits(lc, extra); // send the extra length bits
              }
              dist = zip_d_buf[dx++];
              // Here, dist is the match distance - 1
              code = zip_D_CODE(dist);
      //	Assert (code < D_CODES, "bad d_code");
      
              zip_SEND_CODE(code, dtree);	  // send the distance code
              extra = zip_extra_dbits[code];
              if(extra != 0) {
              dist -= zip_base_dist[code];
              zip_send_bits(dist, extra);   // send the extra distance bits
              }
          } // literal or match pair ?
          flag >>= 1;
          } while(lx < zip_last_lit);
      
          zip_SEND_CODE(zip_END_BLOCK, ltree);
      }
      
      /* ==========================================================================
       * Send a value on a given number of bits.
       * IN assertion: length <= 16 and value fits in length bits.
       */
      var zip_Buf_size = 16; // bit size of bi_buf
      var zip_send_bits = function(
          value,	// value to send
          length) {	// number of bits
          /* If not enough room in bi_buf, use (valid) bits from bi_buf and
           * (16 - bi_valid) bits from value, leaving (width - (16-bi_valid))
           * unused bits in value.
           */
          if(zip_bi_valid > zip_Buf_size - length) {
          zip_bi_buf |= (value << zip_bi_valid);
          zip_put_short(zip_bi_buf);
          zip_bi_buf = (value >> (zip_Buf_size - zip_bi_valid));
          zip_bi_valid += length - zip_Buf_size;
          } else {
          zip_bi_buf |= value << zip_bi_valid;
          zip_bi_valid += length;
          }
      }
      
      /* ==========================================================================
       * Reverse the first len bits of a code, using straightforward code (a faster
       * method would use a table)
       * IN assertion: 1 <= len <= 15
       */
      var zip_bi_reverse = function(
          code,	// the value to invert
          len) {	// its bit length
          var res = 0;
          do {
          res |= code & 1;
          code >>= 1;
          res <<= 1;
          } while(--len > 0);
          return res >> 1;
      }
      
      /* ==========================================================================
       * Write out any remaining bits in an incomplete byte.
       */
      var zip_bi_windup = function() {
          if(zip_bi_valid > 8) {
          zip_put_short(zip_bi_buf);
          } else if(zip_bi_valid > 0) {
          zip_put_byte(zip_bi_buf);
          }
          zip_bi_buf = 0;
          zip_bi_valid = 0;
      }
      
      var zip_qoutbuf = function() {
          if(zip_outcnt != 0) {
          var q, i;
          q = zip_new_queue();
          if(zip_qhead == null)
              zip_qhead = zip_qtail = q;
          else
              zip_qtail = zip_qtail.next = q;
          q.len = zip_outcnt - zip_outoff;
      //      System.arraycopy(zip_outbuf, zip_outoff, q.ptr, 0, q.len);
          for(i = 0; i < q.len; i++)
              q.ptr[i] = zip_outbuf[zip_outoff + i];
          zip_outcnt = zip_outoff = 0;
          }
      }
      
      var zip_deflate = function(str, level) {
          var i, j;
      
          zip_deflate_data = str;
          zip_deflate_pos = 0;
          if(typeof level == "undefined")
          level = zip_DEFAULT_LEVEL;
          zip_deflate_start(level);
      
          var buff = new Array(1024);
          var aout = [];
          while((i = zip_deflate_internal(buff, 0, buff.length)) > 0) {
          var cbuf = new Array(i);
          for(j = 0; j < i; j++){
              cbuf[j] = String.fromCharCode(buff[j]);
          }
          aout[aout.length] = cbuf.join("");
          }
          zip_deflate_data = null; // G.C.
          return aout.join("");
      }
      
      if (! window.RawDeflate) RawDeflate = {};
      RawDeflate.deflate = zip_deflate;
      
      })();
  