TP02E04

import java.util.Scanner;
import java.util.Stack;

public class PuntoCuatro {

    Scanner scanner = new Scanner(System.in);
    public static void main(String[] args) {
        new PuntoCuatro().run();

    }

    void proccess(Stack<Character> stack, char newChar)
    {
        Stack<Character> backupSort = new Stack<Character>();
        while(!stack.isEmpty() && Character.toLowerCase(stack.peek()) > Character.toLowerCase(newChar))
        {
            backupSort.push(stack.pop());
        }
        stack.push(newChar);
        while(!backupSort.isEmpty()) stack.push(backupSort.pop());
    }

    boolean isValidLetter(char xCh)
    {
        return Character.isAlphabetic(xCh);
    }

    char forceReadAnLetter()
    {
        System.out.println("Introduzca una letra (si desea terminar la carga ingrese @):");
        char x =' ';
        String piv;
        try
        {
            while((piv=scanner.next()).length() > 1 || !isValidLetter(x=piv.charAt(0)) && x!= '@') System.out.println("Debe introducir una letra.\nIntroduzca letra:");
        }
        catch(Exception ex)
        {
            System.out.println("Error en la carga.");
        }
        return x;
    }

    boolean isVowel(char xCh)
    {
        xCh = Character.toLowerCase(xCh);
        return xCh == 'a' || xCh == 'e' || xCh == 'i' || xCh == 'o' || xCh == 'u';
    }
    void showStackValues(Stack<Character> stack)
    {
        int countConsonants = stack.size();
        System.out.print("Elementos de la pila:");
        Stack<Character> showStack = new Stack<Character>();
        while(!stack.isEmpty())
        {
            char popped = stack.pop();
            if(isVowel(popped)) countConsonants--;
            showStack.push(popped);
        }
        while(!showStack.isEmpty()) System.out.print(showStack.pop() + (stack.isEmpty() ? "" : ","));
        System.out.println("\nConsonantes:" + countConsonants);

    }

    boolean isRandom()
    {
        char x = '\0';
        while(true)
        {
            try
            {
                System.out.println("¿Generar valores aleatorios? (S/N)");
                x =Character.toUpperCase(scanner.next().charAt(0));
                if(x == 'S' || x == 'N') return x == 'S';
                System.out.println("Opción inválida, reintente.");
            }catch (Exception e) {
                System.out.println("Opción inválida, reintente.");
            }
        }
    }
    static int getRandomIntBetweenRange(double min, double max){
        int x = (int) ((int)(Math.random()*((max-min)+1))+min);
        return x;
    }
    char generateRandomLetter()
    {
        return ((getRandomIntBetweenRange(0,17)%16 == 2) ? '@' : (char) (getRandomIntBetweenRange(0, 25)+65));
    }

    void run()
    {
        char newChar;
        Stack<Character> stackLetters = new Stack<Character>();
        boolean random = isRandom();
        while((!random && (newChar = forceReadAnLetter()) != '@') || random && (newChar = generateRandomLetter()) != '@')
        {
            proccess(stackLetters, newChar);
        }
        showStackValues(stackLetters);
    }

}