class ViewController: UIViewController {

    @IBOutlet weak var dateLabel: UILabel!
    @IBOutlet weak var minTemperature: UILabel!
    @IBOutlet weak var maxTemperature: UILabel!
    @IBOutlet weak var windSpeed: UILabel!
    @IBOutlet weak var rainfall: UILabel!
    @IBOutlet weak var pressure: UILabel!

    @IBOutlet weak var iconImageView: UIImageView!
    @IBAction func onPreviousDayButtonClick(_ sender: Any) {
        if self.day > 0 {
            self.day = self.day - 1
            let data = self.dailyData?[self.day]
            if data != nil{
                self.changeDay(dayInfo: data!)
            }
        }
    }
    @IBAction func onNextDayButtonClick(_ sender: Any) {
        if self.day < 7 {
            self.day = self.day+1
            let data = self.dailyData?[self.day]
            if data != nil{
                self.changeDay(dayInfo: data!)
            }
        }
    }
    private var dailyData : [[String : AnyObject]]? = nil
    private var day : Int = 0
    override func viewDidLoad() {
        super.viewDidLoad()

//        let urlRequestDark = URLRequest(url: URL (string: "https://api.darksky.net/forecast/a133de927c2852dbb273ea1b1071db81/,19.946788")!)
        let urlRequestDark = URLRequest(url: URL (string: "https://api.darksky.net/forecast/a133de927c2852dbb273ea1b1071db81/50.084046,19.946788")!)

        let task = URLSession.shared.dataTask(with: urlRequestDark) { [weak self] (data, response, error) in
            guard error == nil else { return }
            do {
                if let json = try JSONSerialization.jsonObject(with: data!, options: .mutableContainers) as? [String : AnyObject],
                    let daily = json["daily"] as? [String : AnyObject],
                    let data = daily["data"] as? [[String : AnyObject]],
                        data.count > 7 {
                            DispatchQueue.main.sync {
                                    self?.dailyData = data
                                    self?.changeDay(dayInfo: data[self?.day ?? 0])
                            }
                        }

            } catch let jsonError {
                print(jsonError.localizedDescription)
            }
        }
        task.resume()
    }


    func convertDoubleDateToString(date : Double) -> String {
            let date = NSDate(timeIntervalSince1970: date)

        let dateFormatter = DateFormatter()
            dateFormatter.dateFormat = "dd  MMMM yyyy"
            dateFormatter.timeZone = NSTimeZone(name: "UTC") as TimeZone?
        return dateFormatter.string(from: date as Date)
    }

    func changeDay(dayInfo : [String : AnyObject] ) {
        let time : Int64 = dayInfo["time"] as? Int64 ?? 0
        self.dateLabel.text = convertDoubleDateToString(date: Double(time))
        let minTemp : Double = dayInfo["temperatureMin"] as? Double ?? 0
        let minTepmInt = doubleToInteger(data: (minTemp - 32)*5/9)
        self.minTemperature.text = "Min: \(minTepmInt) °C"
        let maxTemp : Double = dayInfo["temperatureMax"] as? Double ?? 0
        let maxTepmInt = doubleToInteger(data: (maxTemp - 32)*5/9)
        self.rainfall.text = "Rainfall: 0 mm"
        self.maxTemperature.text = "Max: \(maxTepmInt) °C"
        var windSpeed : Double = dayInfo["windSpeed"] as? Double ?? 0
        let windSpeedInt = doubleToInteger(data: windSpeed * 1.6)
        self.windSpeed.text = "Wind speed: \(windSpeedInt) km/h"
        let pressure : Double = dayInfo["pressure"] as? Double ?? 0
        self.pressure.text = "Pressure: \(pressure) hPa"

        self.setIconImage(icon: dayInfo["icon"] as! String)


    }

    func doubleToInteger(data:Double)-> Int {
        let doubleToString = "\(data)"
        let stringToInteger = (doubleToString as NSString).integerValue

        return stringToInteger
    }

    func setIconImage(icon : String){

        switch icon {
        case "clear-day":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-summer-100.png")
        case "snow":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-winter-100.png")
        case "fog":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-fog-100.png")
        case "rain":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-rain-100.png")
        case "sleet":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-sleet-100.png")
        case "wind":
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-windy-weather-100.png")
        default:
            self.iconImageView.image = #imageLiteral(resourceName: "icons8-partly-cloudy-day-100.png")
        }

    }
}