/*
	- Password validator
	- Ensures a password entered on registration meets specific requirements.
	- If it returns 0 that means it passed
	- If it returns 1 that means the password has less than the minimum characters
	- If it returns 2 that means the password contains less than the minimum special characters
	- If it returns 3 that means the password contains less than the minimum numbers
	- If it returns 4 that means the password contains less than the minimum capital letters
	
	$password               - The password to validate
	$minChars               - The minimum amount of characters the password is permitted to have
	$leastSpecialCharacters - The minimum amount of special characters permitted
	$leastNumbers           - The minimum amount of numbers permitted
	$leastCapitalLetters    - The minimum amount of capital letters permitted
	*/
	
	public function validatePassword($password, $minChars = 6, $leastSpecialCharacters = 0, $leastNumbers = 0, $leastCapitalLetters = 0) {
		$valid = 0;
		
		if (strlen($password) < $minChars)
			$valid = 1;
		
		$numSpecialChars = 0;
		$numNumbers = 0;
		$numCapitalLetters = 0;
		
		// iterate through each character in password
		for ($i = 0; $i < strlen($password); $i++) {
			$char = substr($password, $i, 1);
			
			if (!preg_match("#^[a-zA-Z0-9]+$#", $char))
				$numSpecialChars++;
			elseif (preg_match("#^[A-Z]+$#", $char))
				$numCapitalLetters++;
			elseif (preg_match("#^[0-9]+$#", $char))
				$numNumbers++;
		}
		
		if ($numSpecialChars < $leastSpecialCharacters)
			$valid = 2;
		
		if ($numNumbers < $leastNumbers)
			$valid = 3;
		
		if ($numCapitalLetters < $leastCapitalLetters)
			$valid = 4;
		
		return $valid;
	}