Prevent users from reaching a negative myCRED point balance. Will decline all point transactions that will result in a users balance going minus.

mycred-no-negative-balance

/**
 * Prevent Negative Balances
 * Make sure users can never get a negative balance. Will allow users
 * to gain a zero balance.
 * @since 1.0
 * @version 1.0
 */
add_filter( 'mycred_add', 'mycred_pro_no_negative_balance', 999, 2 );
function mycred_pro_no_negative_balance( $reply, $request ) {

	// Ignore if allready declined
	if ( $reply === false ) return $reply;

	extract( $request );

	// Ignore point gains
	if ( $amount > 0 ) return $reply;

	// Get uses balance
	$balance = $mycred->get_users_balance( $user_id, $type );

	// Prevent negative balances
	if ( $balance <= 0 || ( $balance - $amount ) < 0 ) return false;

	// all else return default
	return $reply;

}

Where do I add the code to prevent users from getting to a negative balance without earning or buying more points?

im guessing this goes in the the themes functions?

Where do I add the code to prevent users from getting to a negative balance without earning or buying more points?

This would be exactly what I'm looking for as well as it still allows for users to complete the action.