main.cpp

#include<iostream>
#include<vector>
#include<map>
#include <functional>
#include <sstream>

using namespace std;

enum child {
	left,
	right
};

//Available Commands
const string ENCODE_COMMAND = "encode";
const string DECODE_COMMAND = "decode";
const string HELP_COMMAND = "--help";

void decode(string input) {
	map<string, vector<string>> morseTree = { 
        {"ROOT", {"E", "T"}}, 
        {"E", {"I", "A"}}, 
        {"T", {"N", "M"}}, 
        {"I", {"S", "U"}}, 
        {"A", {"R", "W"}}, 
        {"N", {"D", "K"}}, 
        {"M", {"G", "O"}}, 
        {"S", {"H", "V"}}, 
        {"U", {"F", "NIL"}}, 
        {"R", {"L", "NIL"}}, 
        {"W", {"P", "J"}}, 
        {"D", {"B", "X"}}, 
        {"K", {"C", "Y"}}, 
        {"G", {"Z", "Q"}} 
    };
	string output = "", cur = "ROOT";
	int spcount = 0;
	for (auto C : input) {
		if (C == ' ') {
			if (!spcount) { if (cur != "ROOT") output += cur; spcount++; }
			else { output += " "; spcount = 0; }
			cur = "ROOT";
		}
		else {
			spcount = 0;
			if (C == '.')cur = morseTree[cur][child::left];
			else        cur = morseTree[cur][child::right];
		}
	}
	if (cur != "ROOT") output += cur;
	cout << "Decoded Text: " << output << endl;
}

void encode(string input) {
	map<char, string> dec = {
		{'A', ".-"},
		{'B', "-..."},
		{'C', "-.-."},
		{'D', "-.."},
		{'E', "."},
		{'F', "..-."},
		{'G', "--."},
		{'H', "...."},
		{'I', ".."},
		{'J', ".---"},
		{'K', "-.-"},
		{'L', ".-.."},
		{'M', "--"},
		{'N', "-."},
		{'O', "---"},
		{'P', ".--."},
		{'Q', "--.-"},
		{'R', ".-."},
		{'S', "..."},
		{'T', "-"},
		{'U', "..-"},
		{'V', "...-"},
		{'W', ".--"},
		{'X', "-..-"},
		{'Y', "-.--"},
		{'Z', "--.."}
	};
	string output = "";
	for (auto i : input) {
		if (i != ' ') {
			output += dec[toupper(i)] + " ";
		}
		else {
			output += "  ";
		}
	}
	cout << "Encoded Text: " << output << endl;
}

void printHelp() {

	const string helpText(
		"usage: morseconverter\t[decode <text>] Use one space to seperate letters and two spaces to seperate words.\n"
		"\t\t\t[encode <text>] Only alphabet conversion supported. Example: encode 'HeY'\n"	
	);

	std::cout << helpText << endl;
}

//Map to bind commands to functions
map<string, function<void(string)>>  funcMap =
{ { ENCODE_COMMAND, encode},
 { DECODE_COMMAND, decode}
};

int main(int argc, char** argv) {

	if (argc > 1)
	{
		string operation = argv[1];

		if (operation == ENCODE_COMMAND || operation == DECODE_COMMAND)
		{
			if (argc < 3)
			{
				cout << "Too few arguments!\n";
				exit(0);
			}
			else {
				string input = argv[2];
				funcMap[operation](input);
			}
		}
		else if (operation == HELP_COMMAND) printHelp();
		else cout << "Operation not identified! Use --help for more information" << endl;
	}
	else cout << "Not command found, use --help for more information" << endl;
	return 0;
}