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import java.util.*;

import java.io.*;

public class HuffmanTree implements HuffmanInterface{

public String alphabet = "muckd!ap,.re ";

public ArrayList<alphabits> symbols = new ArrayList<alphabits>();

public alphabits[] letters = new alphabits[13];

public BinaryTree<alphabits> root = null;

public int age = 0;

public static void main(String args[]){

HuffmanTree temp = new HuffmanTree();

temp.createTree("EEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEmud!ap. r mkucd!ap,.reemk e");

System.out.println(temp.encodeMessage("eEeEeE"));

}

public void createTree(String sampleText){

for(int i = 0; i < sampleText.length(); i++){

char inspect = Character.toLowerCase(sampleText.charAt(i));

if(alphabet.indexOf(inspect) != -1){

addToHuff(inspect);

}

}

for(int i=0; i<symbols.size(); i++){

letters[i] = symbols.get(i);

}

buildTree(letters);

}

private int findInSymbols(char letter){

int index = -1;

for(int j=0; j < symbols.size(); j++){

if(symbols.get(j).symbol.equals(letter)){

return j;

}

}

return index;

}

private void addToHuff(char letter){

if(symbols.isEmpty())

symbols.add(new alphabits(1, letter));

else {

if(findInSymbols(letter) != -1)

symbols.get(findInSymbols(letter)).weight++;

else

symbols.add(new alphabits(1, letter));

}

}

private void buildTree(alphabits[] symbols){

Queue<BinaryTree<alphabits>> theQueue = new PriorityQueue<BinaryTree<alphabits>>(symbols.length, new CompareHuffmanTrees());

for(alphabits nextSymbol : symbols){

BinaryTree<alphabits> aBinaryTree = new BinaryTree<alphabits>(nextSymbol, null, null, age++);

theQueue.offer(aBinaryTree);

}

while(theQueue.size() > 1){

BinaryTree<alphabits> left = theQueue.poll();

BinaryTree<alphabits> right = theQueue.poll();

double wl = left.getData().weight;

double wr = right.getData().weight;

alphabits sum = new alphabits(wl + wr, null);

BinaryTree<alphabits> newTree = new BinaryTree<alphabits>(sum, left, right, age++);

theQueue.offer(newTree);

}

root = theQueue.poll();

}

private boolean in(BinaryTree<alphabits> root, char symbol){

if(root.isLeaf()){

if(root.getData().symbol.equals(symbol))

return true;

else

return false;

}

else

return (in(root.getLeftSubtree(),symbol) || in(root.getRightSubtree(), symbol));

}

private String code(char symbol){

BinaryTree<alphabits> currentTree = root;

StringBuilder binary = new StringBuilder();

while(!currentTree.isLeaf()){

if(in(currentTree.getLeftSubtree(), symbol)){

binary.append("0");

currentTree = currentTree.getLeftSubtree();

}

else if(in(currentTree.getRightSubtree(), symbol)){

binary.append("1");

currentTree = currentTree.getRightSubtree();

}

}

return binary.toString();

}

public String encodeMessage(String message){

StringBuilder result = new StringBuilder();

message = message.toLowerCase();

for(int i=0; i < message.length(); i++){

if(findInSymbols(message.charAt(i)) != -1){

result.append(code(message.charAt(i)));

}

}

return result.toString();

}

public String decodeMessage(String encodedMessage){

StringBuilder result = new StringBuilder();

BinaryTree<alphabits> currentTree = root;

for(int i = 0; i < encodedMessage.length(); i++){

if(encodedMessage.charAt(i) == '1')

currentTree = currentTree.getRightSubtree();

else

currentTree = currentTree.getLeftSubtree();

if(currentTree.isLeaf()){

alphabits theData = currentTree.getData();

result.append(theData.symbol);

currentTree = root;

}

}

return result.toString();

}

private static class alphabits implements Serializable {

private double weight;

public Character symbol;

public alphabits(double weight, Character symbol){

this.weight = weight;

this.symbol = symbol;

}

}

private static class CompareHuffmanTrees implements Comparator<BinaryTree<alphabits>> {

public int compare(BinaryTree<alphabits> treeLeft, BinaryTree<alphabits> treeRight) {

double wLeft = treeLeft.getData().weight;

double wRight = treeRight.getData().weight;

if(Double.compare(wLeft, wRight) == 0){

if(treeLeft.isLeaf() && !treeRight.isLeaf())

return -1;

else if(!treeLeft.isLeaf() && treeRight.isLeaf())

return 1;

else if(treeLeft.isLeaf() && treeRight.isLeaf()){

if(treeLeft.getData().symbol < treeRight.getData().symbol)

return -1;

else if(treeLeft.getData().symbol > treeRight.getData().symbol)

return 1;

}

else if(!treeLeft.isLeaf() && !treeRight.isLeaf()){

if(treeLeft.age < treeRight.age)

return -1;

else if (treeLeft.age > treeRight.age)

return 1;

}

}

return Double.compare(wLeft, wRight);

}

}

}