func greetingLogic() -> String { let hour = Calendar.current.component(.hour, from: Date()) let NEW_DAY = 0 let NOON = 12 let SUNSET = 18 let MIDNIGHT = 24 var greetingText = "Hello" // Default greeting text switch hour { case NEW_DAY..<NOON: greetingText = "Good Morning" case NOON..<SUNSET: greetingText = "Good Afternoon" case SUNSET..<MIDNIGHT: greetingText = "Good Evening" default: _ = "Hello" } return greetingText }