#include <iostream>

using namespace std;

bool GetContinue();
bool GetContinue2();
string Lower(string word);
void  Lower2(string & word);

int GetShiftAmount();
void GetMessage(string & message);


int main() {
    bool keepAtIt{false};
    int shiftAmount{0};
    string plainText;

    keepAtIt = GetContinue2();
    while(keepAtIt) {

        shiftAmount = GetShiftAmount();
        GetMessage(plainText);
/*

     Encode the plain text message
     print the crypt text message
*/
        cout << "Encrypting a message " << plainText 
             << " with a shift of " << shiftAmount
             << endl;

        //Ask if they want to encrypt a message
        keepAtIt = GetContinue2();
    }
    return 0;
}



/*
GetContinue:
    This function asks the user if they wish to continue
    Input: no input from main
    Output: returns a bool  (yes continue -> true, no don't continue -> false)
*/
bool GetContinue2() {
    string answer;
    bool keepGoing{false};

    while( answer != "yes" and answer != "no") {
        cout << "Do you wish to encrypt a message (yes/no)? ";
        getline(cin, answer);
        cout << "answer =  " << answer << endl;
        Lower2(answer);
        cout << "answer =  " << answer << endl;
    }

    if (answer == "yes") {
       keepGoing = true;
    }

    return keepGoing;
}

bool GetContinue() {
    string input;
    string answer;
    bool keepGoing{false};

    while( answer != "yes" and answer != "no") {
        cout << "Do you wish to encrypt a message (yes/no)? ";
        getline(cin, input);
        cout << "input =  " << input << endl;
        cout << "answer =  " << answer << endl;
        answer = Lower(input);
        cout << "input =  " << input << endl;
        cout << "answer =  " << answer << endl;
    }

    if (answer == "yes") {
       keepGoing = true;
    }

    return keepGoing;
}

string Lower(string word){
   size_t i;
   cout << "Lower Got " << word << endl;

   for(i =0; i < word.size(); ++i) {
       word[i] = tolower(word[i]);
   }

   cout << "Lower Returning " << word << endl;

   return word;
}

void Lower2(string & word){
   size_t i;
   cout << "Lower Got " << word << endl;

   for(i =0; i < word.size(); ++i) {
       word[i] = tolower(word[i]);
   }

   cout << "Lower Returning " << word << endl;
}

int GetShiftAmount(){
    return 3;
}

void GetMessage(string & message){
     message = "Hello World";
}

int FixNumber(int number) {
    while (number < 0) {
        number += 26;
    }
    return number%26;
}

char ShiftLetter(char old, int shift) {
    int pos = static_cast<int>(old -'a');
    char result;
    pos += shift;
    pos = FixNumber(pos);

    result = static_cast<char>('a' + pos);
    return result;
}