From 816548386eba184821e8a48f812bca0055eaaf73 Mon Sep 17 00:00:00 2001
From: Denis Molony <dmolony@iinet.net.au>
Date: Wed, 17 Aug 2016 12:20:00 +1000
Subject: [PATCH] added walk()

---
 .../diskbrowser/wizardry/Huffman.java         | 44 +++++++++++++++++--
 .../wizardry/Wizardry4BootDisk.java           |  6 +--
 2 files changed, 43 insertions(+), 7 deletions(-)

diff --git a/src/com/bytezone/diskbrowser/wizardry/Huffman.java b/src/com/bytezone/diskbrowser/wizardry/Huffman.java
index a05b589..6426a65 100644
--- a/src/com/bytezone/diskbrowser/wizardry/Huffman.java
+++ b/src/com/bytezone/diskbrowser/wizardry/Huffman.java
@@ -1,8 +1,10 @@
 package com.bytezone.diskbrowser.wizardry;
 
+import com.bytezone.diskbrowser.applefile.AbstractFile;
+
 // Based on a pascal routine by Tom Ewers
 
-public class Huffman
+public class Huffman extends AbstractFile
 {
   private final byte[] tree;
   private final byte[] left;
@@ -13,8 +15,12 @@ public class Huffman
   private int currentByte;
   private byte[] message;
 
-  public Huffman (byte[] buffer)
+  private String treeContents;
+
+  public Huffman (String name, byte[] buffer)
   {
+    super (name, buffer);
+
     tree = new byte[256];
     left = new byte[256];
     right = new byte[256];
@@ -47,7 +53,7 @@ public class Huffman
     {
       if (bitNo-- == 0)
       {
-        bitNo = 7;
+        bitNo += 8;
         currentByte = message[msgPtr++] & 0xFF;
       }
 
@@ -68,4 +74,36 @@ public class Huffman
       }
     }
   }
+
+  @Override
+  public String getText ()
+  {
+    if (treeContents == null)
+    {
+      StringBuilder text = new StringBuilder ();
+      walk (0, "", text);
+      treeContents = text.toString ();
+    }
+    return treeContents;
+  }
+
+  private void walk (int treePtr, String path, StringBuilder text)
+  {
+    if ((tree[treePtr] & 0x01) == 0)
+      walk (left[treePtr] & 0xFF, path + "1", text);
+    else
+      print (path + "1", left[treePtr], text);
+
+    if ((tree[treePtr] & 0x02) == 0)
+      walk (right[treePtr] & 0xFF, path + "0", text);
+    else
+      print (path + "0", right[treePtr], text);
+  }
+
+  private void print (String path, byte value, StringBuilder text)
+  {
+    int val = value & 0xFF;
+    char c = val < 32 || val >= 127 ? ' ' : (char) val;
+    text.append (String.format ("%3d  %1.1s  %s%n", val, c, path));
+  }
 }
\ No newline at end of file
diff --git a/src/com/bytezone/diskbrowser/wizardry/Wizardry4BootDisk.java b/src/com/bytezone/diskbrowser/wizardry/Wizardry4BootDisk.java
index 06b3ebb..8aab2fc 100644
--- a/src/com/bytezone/diskbrowser/wizardry/Wizardry4BootDisk.java
+++ b/src/com/bytezone/diskbrowser/wizardry/Wizardry4BootDisk.java
@@ -94,11 +94,9 @@ public class Wizardry4BootDisk extends PascalDisk
 
       byte[] buffer = fileEntry.getDataSource ().buffer;
 
-      Huffman huffman = new Huffman (buffer);
+      Huffman huffman = new Huffman ("Huffman tree", buffer);
       messageBlock.setHuffman (huffman);
-
-      //      for (int msg = 2043; msg <= 2045; msg++)
-      //        System.out.println (huffman.getMessage (messageBlock.getMessage (msg)));
+      fileEntry.setFile (huffman);
     }
   }