package com.thealgorithms.strings;

/**
 * Vowel Count is a system whereby character strings are placed in order based
 * on the position of the characters in the conventional ordering of an
 * alphabet. Wikipedia: https://en.wikipedia.org/wiki/Alphabetical_order
 */
class CheckVowels {

    public static void main(String[] args) {
        assert !hasVowels("This is a strings");
        assert hasVowels("Hello World");
        assert hasVowels("Java is fun");
        assert !hasVowels("123hi");
        assert hasVowels("Coding vs Programming");
    }

    /**
     * Check if a string is has vowels or not
     *
     * @param input a string
     * @return {@code true} if given string has vowels, otherwise {@code false}
     */
    public static boolean hasVowels(String input) {
        if (input.matches("[AEIOUaeiou]")) {
            countVowels(input);
            return true;
        }
        return false;
    }

    /**
     * count the number of vowels
     *
     * @param input a string prints the count of vowels
     */
    public static void countVowels(String input) {
        input = input.toLowerCase();
        int count = 0;
        int i = 0;
        while (i < input.length()) {
            if (input.charAt(i) == 'a'
                    || input.charAt(i) == 'e'
                    || input.charAt(i) == 'i'
                    || input.charAt(i) == 'o'
                    || input.charAt(i) == 'u') {
                count++;
            }
            i++;
        }
        System.out.println(count);
    }
}