public Tree(SortedSet <Symbol> symbols)
{
// Initialize nodes list
SortedSet <TreeNode> nodes = new SortedSet <TreeNode>();
foreach (Symbol symbol in symbols)
{
nodes.Add(new TreeNodeLeaf(symbol));
}
// Special case because merge won't work
if (nodes.Count == 1)
{
root = new TreeNodeInternal();
root.next[0] = nodes.First();
root.next[1] = new TreeNodeLeaf(new CharSymbol(0, 0)); // TODO: Terrible but I do not care
return;
}
// Create tree from Nodes
while (nodes.Count > 1)
{
// Merge 2 nodes together
TreeNode node0 = nodes.Min();
nodes.Remove(node0);
TreeNode node1 = nodes.Min();
nodes.Remove(node1);
TreeNodeInternal mergedNode = new TreeNodeInternal(node0, node1);
nodes.Add(mergedNode);
}
root = nodes.First() as TreeNodeInternal;
}
public DecodeState(BinaryWriter output, Tree tree)
{
this.output = output;
this.tree = tree;
writtenBytes = 0;
node = tree.root;
}
public void ParseBit(bool bit)
{
TreeNode next = node.next[bit ? 1 : 0];
// Continue parsing
if (next is TreeNodeInternal inter)
{
node = inter;
}
// Output byte from leaf, run away
else if (next is TreeNodeLeaf leaf)
{
leaf.symbol.Write(output);
node = tree.root;
writtenBytes++;
}
}
public Tree(Dictionary <BinaryCode, Symbol> codes)
{
root = new TreeNodeInternal();
// Recreate Tree from provided BinaryCodes
foreach (KeyValuePair <BinaryCode, Symbol> entry in codes)
{
BinaryCode code = entry.Key;
Symbol sym = entry.Value;
TreeNodeInternal node = root;
TreeNodeInternal prev = null;
// Traverse the tree and create necessary internal nodes on fly
// FIXME: Dirty but idk how to fix
int bitint = 0;
foreach (bool bit in code)
{
prev = node;
bitint = bit ? 1 : 0;
if (node.next[bitint] == null)
{
node.next[bitint] = new TreeNodeInternal();
}
if (node.next[bitint] is TreeNodeInternal inter)
{
node = inter;
}
else
{
throw new ArgumentException("Invalid Code!");
}
}
prev.next[bitint] = new TreeNodeLeaf(sym);
}
}