import Foundation public func stringForDuration(_ duration: Int32, position: Int32? = nil) -> String { var duration = duration if let position = position { duration = max(0, duration - position) } let hours = duration / 3600 let minutes = duration / 60 % 60 let seconds = duration % 60 let durationString: String if hours > 0 { durationString = String(format: "%d:%02d:%02d", hours, minutes, seconds) } else { durationString = String(format: "%d:%02d", minutes, seconds) } return durationString }