package Week9_Lab;

public class RandomCharacter {

    public static char getRandomLowerCaseLetter(){
        return (char)('a' + Math.random() * ('z' - 'a' + 1));
    }
    public static char getRandomUpperCaseLetter(){
        return (char)('A' + Math.random() * ('Z' - 'A' + 1));
    }
    public static char getRandomDigitCharacter(){
        return (char)('0' + Math.random() * ('9' - '0' + 1));
    }
    public static char getRandomCharacter(){
        int num = (int)(Math.random() * 3);
        return switch (num) {
            case 0 -> getRandomLowerCaseLetter();
            case 1 -> getRandomUpperCaseLetter();
            case 2 -> getRandomDigitCharacter();
            default -> ' ';
        };
    }

    public int genPrime() {
        int num;
        do {
            num = 0;
            for (int i = 0; i < 10; i++) {
                num = num * 10 + (getRandomDigitCharacter() - '0');
            }
        } while (!isPrime(num) || (int) (Math.log10(num) + 1) != 10);
        return num;
    }

    public boolean isPrime(int inputNum){
        if (inputNum <= 3 || inputNum % 2 == 0)
            return inputNum == 2 || inputNum == 3;

        int divisor = 3;
        while ((divisor <= Math.sqrt(inputNum)) && (inputNum % divisor != 0))
            divisor += 2;
        return inputNum % divisor != 0;
    }

    public static void main(String[] args) {
        for (int i = 0; i < 15; i++){
            System.out.print(getRandomLowerCaseLetter() + " ");
        }
        System.out.println();

        for (int i = 0; i < 15; i++){
            System.out.print(getRandomUpperCaseLetter() + " ");
        }
        System.out.println();

        for (int i = 0; i < 15; i++){
            System.out.print(getRandomDigitCharacter() + " ");
        }
        System.out.println();

        for (int i = 0; i < 15; i++){
            System.out.print(getRandomCharacter() + " ");
        }
        System.out.println();

        System.out.println(new RandomCharacter().genPrime());

    }
}