Setting Icon Images- Build a simple weather app in Swift

import Foundation
import UIKit

struct Current {

    var currentTime: String?
    var temperature: Int
    var humudity: Double
    var preciProbability: Double
    var summary: String
    var icon: UIImage?


    init(weatherDictionary: NSDictionary) {
        let currentWeather = weatherDictionary["currently"] as
           NSDictionary



        temperature = currentWeather["temperature"] as Int
        humudity = currentWeather["humidity"] as Double
        preciProbability = currentWeather["precipProbability"] as Double
        summary = currentWeather["summary"] as String


        let currentTimeIntValue = currentWeather["time"] as Int
         currentTime = dateStringFromUnixTime(currentTimeIntValue)

         let iconString = icon = currentWeather["icon"] as String
          icon = weatherIconFromString(iconString)
    }

    func dateStringFromUnixTime(unixTime: Int) -> String  {
        let timeInSeconds = NSTimeInterval(unixTime)
        let weatherDate = NSDate(timeIntervalSince1970:timeInSeconds)
        let dateFormatter = NSDateFormatter()
        dateFormatter.timeStyle = .MediumStyle 
        dateFormatter.timeStyle = .ShortStyle

        return dateFormatter.stringFromDate(weatherDate)

    }

    func weatherIconFromString(stringIcon: String) -> UIImage {
        var imageName: String

        switch stringIcon {
        case "clear-day":
            imageName = "clear-day"
        case "clear-night":
            imageName = "clear-night"
        case "rain":
            imageName = "rain"
        case "snow":
            imageName = "snow"
        case "sleet":
            imageName = "sleet"
        case "wind":
            imageName = "wind"
        case "fog":
            imageName = "fog"
        case "cloudy":
            imageName = "cloudy"
        case "partly-cloudy-day":
            imageName = "partly-cloudy"
        case "partly-cloudy-night":
            imageName = "cloudy-night"
        default:
            imageName = "default"
        }

        var iconImage = UIImage(named: imageName)
        return iconImage!


}
}