Huffman.cpp

#include "Huffman.H"

#include <iostream>

void Huffman::generateBitMapHelper(std::shared_ptr<Node> curr, std::string bin){
    if(curr->isLeaf()){
		_bitMap[curr->letter] = bin;
    }
    else{
        generateBitMapHelper(curr->left,bin+"0");
        generateBitMapHelper(curr->right,bin+"1");
    }		
}

void Huffman::generateBitMap(){ //Wrapper class to recursively call enumerateTreeHelper with DFS
	generateBitMapHelper(_tree,"");
}

void Huffman::printBitMap(){
	cout << "MAP TABLE BEGIN\n" << endl;
	for (auto it = _bitMap.begin();it != _bitMap.end();it++){
		cout << it->first  << " : " << it->second << endl; 	
	}
	cout << "MAP TABLE END\n" << endl;
}

string convertToBits(string uncompressed){ //Converts the string format bits into char
	string compressed = "";
	int index = 0;
	char comp;
	for (char c : uncompressed){
		if (!index){
			comp = 0x0;
		}	

		comp = comp | atoi(&c);

		if (index == 7){
			compressed += comp;
		}
		else{
			comp = comp << 1; // Shift over one bit
		}
		index = (index + 1) % 8;
	}

	if(index){ // If body is not a multiple of 8, then the last few bits need to be copied into compressed
		comp = comp << (7-index);
		compressed += comp;
	}
	
	return compressed;
}

string convertToString(string compressed){//converts from binary form to string form.
	string total = "";
	for (char c : compressed){
		string tmp = "";
		for (int i = 0; i < 8;i++){
			tmp = to_string(c & 0x1) + tmp;
			c = c >> 1;
		}
		total += tmp;
	}
	return total;
}

template <class Ptr>
string preOrder(Ptr curr, string & letters){
    if (curr->isLeaf()){
        letters += string(1,curr->letter);
        return "1";
    }
    return "0" + preOrder(curr->left,letters) + preOrder(curr->right,letters);
}

void Huffman::printPreorder(){
    string letts = "";
    cout << preOrder(_tree,letts) << endl;
}