/*
  Name: LetterFrequency
  Copyright: 2009
  Author: Yong Joseph Bakos
  Date: 24/10/09
  Description: https://csci261.mines.edu/csci261/MinesQuestion/LetterFrequencyByFunction
*/

#include <cstdlib>
#include <iostream>
#include <fstream>
#include <string>
#include "letterfrequencies.h"

using namespace std;

int main()
{
    const int ALPHA_LOWER = 'a';
    const int ALPHA_UPPER = 'z';
    const int ALPHA_RANGE = ALPHA_UPPER - ALPHA_LOWER + 1;
    
    char c;
    int frequencies[ALPHA_RANGE] = {0};
    string text;
    int idxleast(0), idxmost(0), idxsecond_to_most(0); 
    ifstream data_file("INPUT.TXT");

    if (!data_file) {
        cerr << "There was a problem opening the data file." << endl;
        system("PAUSE");
        exit(1);
    }

//    while (data_file >> c) {
//        if ((c < ALPHA_LOWER || c > ALPHA_UPPER)) {
//            continue;
//        }
//        frequencies[c - ALPHA_LOWER]++;
//    }

    if(!getline(data_file, text, char(0))) {
        exit(1);
    }

    for(int i = 0; i < text.length(); i++) {
        if( text[i] >= ALPHA_LOWER && text[i] <= ALPHA_UPPER ) {
            frequencies[text[i] - ALPHA_LOWER]++;
        }
    }
    
    for (int i = 0; i < ALPHA_RANGE; i++) {
        if (frequencies[i] < frequencies[idxleast]) {
            idxleast = i;
        }
    }
    
    for (int i = 0; i < ALPHA_RANGE; i++) {
        if (frequencies[i] > frequencies[idxmost]) {
            idxmost = i;
        }
    }
    
    int idxtmpmax(0);
    for (int i = 0; i < ALPHA_RANGE; i++) {
        if (i == idxmost) continue;
        if (frequencies[i] >= frequencies[idxtmpmax] &&
            frequencies[i] <= frequencies[idxmost]) {
            idxtmpmax = i;
            idxsecond_to_most = i;
        }
    }

    cout.width(25);
    cout << "Least frequent letter: ";
    cout.width(3);
    cout << char(idxleast + ALPHA_LOWER) << endl;
    cout.width(25);
    cout << "2nd to most frequent: ";
    cout.width(3);
    cout << char(idxsecond_to_most + ALPHA_LOWER) << endl;
    cout.width(25);
    cout << "Most frequent letter: ";
    cout.width(3);
    cout << char(idxmost + ALPHA_LOWER) << endl;

    system("PAUSE");
    return 0;
}