public void Encode()
{
var map = CountChars();
var tree = new HTree(map.OrderBy(pair => pair.Value).ThenByDescending(pair => pair.Key));
var table = tree.Table;
Encrypt(map, table);
}
public void Decode()
{
var stream = new FileStream(_path, FileMode.Open, FileAccess.Read);
var map = CreateCountMap(stream);
var tree = new HTree(map.OrderBy(pair => pair.Value).ThenByDescending(pair => pair.Key));
var table = tree.Table;
var path = Path.GetFullPath(_path);
var destination = Path.GetDirectoryName(path) + "/" + Path.GetFileNameWithoutExtension(Path.GetFileNameWithoutExtension(path)) +
"_decoded" + Path.GetExtension(Path.GetFileNameWithoutExtension(path));
int size = (int)(stream.Length - stream.Position);
var outputStream = new BinaryWriter(new FileStream(destination, FileMode.Create, FileAccess.Write));
StringBuilder builder = new StringBuilder();
for (long remaining = stream.Length - stream.Position; remaining > 0; remaining -= size)
{
size = (int)Math.Min(size, remaining);
var buffer = new byte[size];
stream.Read(buffer, 0, size);
HNode node;
for (int i = 0; i < size; i++) // idx in buffer in block
{
var bits = new BitSet(buffer[i]);
for (int j = 0; j < 8;) // idx in byte
{
for (node = tree.Root; !node.IsLeaf;)
{
if (j >= 8 && !node.IsLeaf)
{
j = 0;
if (i + 1 >= size)
{
break;
}
bits = new BitSet(buffer[++i]);
}
if (bits[j] == 0)
{
node = node.Left;
}
else if (bits[j] == 1)
{
node = node.Right;
}
j++;
}
outputStream.Write(node.Data);
map[node.Data]--;
if (map[node.Data] == 0)
{
map.Remove(node.Data);
}
if (map.Count == 0)
{
outputStream.Close();
return;
}
}
}
}
outputStream.Close();
}