/******************************************************************************


*******************************************************************************/
#include <iostream>
#include <time.h>
using namespace std;

bool stringCheck(string userInput){
    int userInputLength = userInput.size();
    for(int i = 0; i < userInputLength; ++i){
        if((userInput.at(i) != '+') && (userInput.at(i) != '-') &&  (userInput.at(i) != '/') && (userInput.at(i) != '*' )){
            return false;
        }
    }
    return true;
}

int reverseOperator(char userOperator){
    if (userOperator == '+'){
        return 1;
    }
    else if (userOperator == '-'){
        return 2;
    }
    else if (userOperator == '/'){
        return 3;
    }
    else if (userOperator == '*'){
        return 4;
    }
}


float calculateNumbers(int op, int a, int b){
    float answer;
    if (op == 1){
        answer = a + b;
    }
    else if(op == 2){
        answer = a - b;
    }
    else if(op == 3){
        answer = a / b;
    }
    else if(op == 4){
        answer = a * b;
    }
    return answer;
}

string changeOperator(int number){
    string operatorSign;
    if (number == 1){
        operatorSign = "+";
    }
    else if (number == 2){
        operatorSign = "-";
    }
    else if (number == 3){
        operatorSign = "/";
    }
    else if (number == 4){
        operatorSign = "*";
    }
    return operatorSign;
}


int main()
{
    int startValue;
    int endingValue;
    int counter = 1;
    srand(time(nullptr));
    int puzzleChosen = rand() % 3185 + 1;

    cout << "**** Begin Debug Display ****" << endl;
    cout << "Enter the beginning solution to be printed:";
    cin >> startValue;
    cout << endl;
    cout << "Enter the end solution to be printed:";
    cin >> endingValue;
    cout << endl;

    for(float a = 1; a <= 9; ++a){
        for(float b = 1; b <= 9; ++b){
            for(float c = 1; c <= 9; ++c){
                for(float d = 1; d <= 9; ++d){
                    for( int operator1 = 1; operator1 <= 4; ++operator1 ){
                        for( int operator2 = 1; operator2 <= 4; ++operator2){
                            for( int operator3 = 1; operator3 <= 4; ++operator3){
                                string displayChar1 = changeOperator(operator1);
                                string displayChar2 = changeOperator(operator2);
                                string displayChar3 = changeOperator(operator3);
                                float result1 = calculateNumbers(operator1, a, b);
                                float result2 = calculateNumbers(operator2, result1, c);
                                float result3 = calculateNumbers(operator3, result2, d);
                                if (result3 == 24){
                                        if(counter >= startValue && counter <= endingValue){
                                        cout << counter << ":" << a <<  displayChar1 <<  b <<  displayChar2 <<  c << displayChar3 << d;
                                        cout << "=" << result3;
                                        cout << endl;
                                        }
                                    if (counter == puzzleChosen)
                                    {
                                        cout << "Puzzle chosen is #" << counter << ":" << a << displayChar1 << b << displayChar2 << c << displayChar3 << d;
                                        cout << endl;
                                        cout << "***End of the Debug Display***" << endl;
                                        cout << "The numbers to use are " << a << " " << b << " " << c << " " << d << endl;
                                        cout << "Enter the three operators to be used (+, -, * or / ):" << endl;
                                        bool isInvalidUserInput = false;
                                        while (true){
                                        string userOperators;
                                        cin >> userOperators;
                                        int sizeOfUserInput = userOperators.size();
                                        if(sizeOfUserInput!= 3){
                                            cout << endl;
                                            cout << "invalid number of characters entered, please try again";
                                            cout << endl;
                                        }
                                        if(stringCheck(userOperators) == false){
                                            cout << endl;
                                            cout << "invalid characters entered, please try again" << endl;

                                        }

                                        else if((displayChar1[0] != userOperators.at(0) || displayChar2[0] != userOperators.at(1) || displayChar3[0] != userOperators.at(2)) && (sizeOfUserInput == 3 && stringCheck(userOperators) == true)) {
                                                isInvalidUserInput = true;
                                                float res1 = calculateNumbers(reverseOperator(userOperators.at(0)), a , b);
                                                float res2 = calculateNumbers(reverseOperator(userOperators.at(1)), res1, c);
                                                float res3 = calculateNumbers(reverseOperator(userOperators.at(2)), res2, d);
                                                cout << a << " " << userOperators.at(0) << " " << b << " = " << res1 << endl;
                                                cout << res1 << " " << userOperators.at(1) << " " << c << " = " << res2 << endl;
                                                cout << res2 << " " << userOperators.at(2) << " " << d << " = " << res3 << endl;
                                                cout << "incorrect: The correct answer was:" << endl;
                                                cout << a << displayChar1[0] << b << displayChar2[0] << c << displayChar3[0] << d << endl;
                                                break;
                                        }
                                        if (displayChar1[0] == userOperators.at(0) && displayChar2[0] == userOperators.at(1) && displayChar3[0] == userOperators.at(2)){
                                            isInvalidUserInput = true;
                                            cout << a << displayChar1[0] << b << " = " << result1 << endl;
                                            cout << result1 << displayChar2[0] << c << " = " << result2 << endl;
                                            cout << result2 << displayChar3[0] << d << " = " << result3 << endl;
                                            cout << "Well done!" << endl;
                                            break;
                                            }

                                        }


                                    }
                                    ++counter;

                                }

                            }
                        }
                    }
                }
        }
    }

}
return 0;
}