using namespace std;
#include <iostream>
#include <vector>
#include <fstream>
#include <string>
#include <ctime>

const string data = "Data.txt";
void ReadData(vector<string> & BigList);
void PrintVector(const vector<string> & V);
void GenerateChallenge(vector<string> & SmallList, const vector<string> & BigList, int wordLn);
int CheckAnswer(const string & word, const string & guess);
void StartGame(const string & word);

int main()
{
    srand(time(NULL));
    vector<string> BigList, SmallList;
    string word;
    int diff;
    ReadData(BigList);
    cout << "Difficulty (1-5)? ";
    cin >> diff;

    GenerateChallenge(SmallList, BigList, diff*3);
    PrintVector(SmallList);
    word = SmallList[rand() % SmallList.size()];
    StartGame(word);
    return 0;
}

void StartGame(const string & word) {
    int attempts = 4;
    string guess;

    while (attempts != 0) {
        cout << "Guess (" << attempts << " left) ? ";
        cin >> guess;
        cout << CheckAnswer(word, guess) << "/" << word.length() << " correct" << endl;
        attempts--;
        if (CheckAnswer(word, guess) == word.length()) {
            cout << "You win!" << endl;
            break;
        }
    }
}

void ReadData(vector<string> & BigList) {
    ifstream fd(data);
    string word;
    while (!fd.eof()) {
        fd >> word;
        BigList.push_back(word);
    }
    fd.close();
}

bool Exists(const vector<string> & SmallList, const string & word) {
    for (size_t i = 0; i < SmallList.size();  i++)
        if (SmallList[i] == word)
            return true;
    return false;
}

void GenerateChallenge(vector<string> & SmallList, const vector<string> & BigList, int wordLn) {
    unsigned long rndNumber;
    while (SmallList.size() != 7) {

        int divideRnd = rand() % (BigList.size() / RAND_MAX + 1);
        if (divideRnd == BigList.size() / RAND_MAX)
            rndNumber = (rand() % (BigList.size() - divideRnd * RAND_MAX)) + (divideRnd * RAND_MAX);
        else
            rndNumber = rand() + divideRnd * RAND_MAX;

        for (unsigned long i = rndNumber; i < BigList.size(); i++) {
            if (BigList[i].length() == wordLn && !Exists(SmallList, BigList[i])) {
                SmallList.push_back(BigList[i]);
                break;
            }
        }
    }
}

int CheckAnswer(const string & word, const string & guess) {
    int count = 0;
    for (size_t i = 0; i < word.length(); i++)
        if (toupper(word[i]) == toupper(guess[i]))
            count++;

    return count;
}

void PrintVector(const vector<string> & V) {
    for (size_t i = 0; i < V.size(); i++) {
        cout << V[i] << endl;
    }
}