public class Binnenmajuskel extends MiniJava {

	public static void main(String[] args) {
		String startCase = "";
		String upperCase = "";
		String snakeCase = "";
		String pascalCase = "";
				
		
		// ask user for next term, check if it's valid, modify it in the
		// given manner (startcase, uppercase, ...) and append it to variables:
		while (true) {
			String input = readString("Begriff eingeben:");
			
			// empty string -> done
			if (input.length() == 0)
				break;  // exit loop
			
			// check if input is valid; and save it all lowercase
			String lowerInput = "";
			boolean valid = true;
			for (int i = 0; i < input.length(); ++i) {
				char c = input.charAt(i);
				if (c >= 'A' && c <= 'Z')  // A-Z
					lowerInput += (char) (c+32);
				else if (c >= 'a' && c <= 'z')  // a-z
					lowerInput += c;
				else {  // invalid
					valid = false;
					break;  // exit loop (not required)
				}
			}
			if (!valid) { // not valid = (valid == false)
				write("Diese Eingabe ist unültig (nur Buchstaben und Unterstriche)!");
				continue;  // continue loop (wait for next input)
			}
			
			// append modified string to the variables:

			if (snakeCase.length() > 0)  // is not first word
				snakeCase += '_';
			
			for (int i = 0; i < lowerInput.length(); ++i) {
				char c = lowerInput.charAt(i);
				
				upperCase += (char) (c-32);  // UPPERCASE
				snakeCase += c;  // snake_case
				
				// PascalCase
				if (i >= 1)
					pascalCase += c;
				else  // -> upper char if at first char (and is not underscore)
					pascalCase += (char) (c-32);
				
				// Startcase:
				if (i > 0 || startCase.length() > 0)
					startCase += c;
				else  // -> upper char if at first char in first word (and is not underscore)
					startCase += (char) (c-32);
			}			
		}
		
		write("Startcase:  " + startCase + "\n"
		    + "UPPERCASE:  " + upperCase + "\n"
		    + "snake_case: " + snakeCase + "\n"
		    + "PascalCase: " + pascalCase + "\n");
	}
	
}