public class TimerManager{
    static let instance = TimerManager()
    private var delegates = [TimerDelegate]()
    var currentTimers = [TimerObject]()

    public func timerAdded(timer: TimerObject){
        self.currentTimers.append(timer)
        timer.timer = NSTimer.scheduledTimerWithTimeInterval(1.0, target: self, selector: #selector(persistTimer(_:)), userInfo: "(TimerManager.instance.currentTimers.count-1)", repeats: false)
        timer.isRunning = true
        for delegate in delegates{
            delegate.startTimer(self.currentTimers[self.currentTimers.count-1])
        }
    }

    @objc public func persistTimer(timer: NSTimer){
        if let indexString = timer.userInfo as? String{
            if let index = Int(indexString){
                if let currentTimer = self.currentTimers[safe: index]{
                    if currentTimer.isRunning{
                        currentTimer.timeDuration -= 1
                        for delegate in delegates{
                            delegate.timerStarted(index)
                        }
                    }
                }
            }
        }

    }

    public func addTime(timerId: Int, amount: Int){
        for delegate in delegates{
            delegate.addTimeToTimer(timerId, amount: amount)
            UIApplication.sharedApplication().cancelLocalNotification(currentTimers[timerId].notification)
            currentTimers[timerId].notification.fireDate = NSDate(timeIntervalSinceNow: Double(currentTimers[timerId].timeDuration))
        }
    }

    public func subtractTime(timerId: Int, amount: Int){
        for delegate in delegates{
            delegate.subtractTimeFromTimer(timerId, amount: amount)
            UIApplication.sharedApplication().cancelLocalNotification(currentTimers[timerId].notification)
            currentTimers[timerId].notification.fireDate = NSDate(timeIntervalSinceNow: Double(currentTimers[timerId].timeDuration))
        }
    }

    public func removeDelegate(removedDelegate: TimerDelegate){
        for i in 0..<delegates.count{
            if delegates[i] === removedDelegate{
                delegates.removeAtIndex(i)
            }
        }
    }

    public func cancelTimer(timerId: Int){
        let currentTimer = currentTimers[timerId]
        currentTimer.timer.invalidate()
        UIApplication.sharedApplication().cancelLocalNotification(currentTimer.notification)
        currentTimers.removeAtIndex(timerId)
    }

    private init() {}
}

//Delete cell functionality
    public override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
        if( editingStyle == .Delete){
            let screenSize: CGRect = UIScreen.mainScreen().bounds
            let screenWidth = screenSize.width
            let screenHeight = screenSize.height
            let deletedTimer = TimerManager.instance.currentTimers[indexPath.row]
            if (deletedTimer.isRunning){
                deletedTimer.timer.invalidate()// <-- invalidates all timers for some reason
                UIApplication.sharedApplication().cancelLocalNotification(deletedTimer.notification)
            }
            TimerManager.instance.currentTimers.removeAtIndex(indexPath.row)
            self.tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
            self.tableView.frame = CGRect.init(x: 0, y: 100, width: screenWidth, height: screenHeight * 0.0625 * CGFloat(TimerManager.instance.currentTimers.count))
        }
    }

public func startTimer(timer: TimerObject) {
        let newIndexPath = NSIndexPath(forRow: TimerManager.instance.currentTimers.count-1, inSection: 0)
        self.tableView.insertRowsAtIndexPaths([newIndexPath], withRowAnimation: .Bottom)
        let screenSize: CGRect = UIScreen.mainScreen().bounds
        let screenWidth = screenSize.width
        let screenHeight = screenSize.height
        self.view.frame = CGRectMake(0, 100, screenWidth, screenHeight * 0.0625 * CGFloat(TimerManager.instance.currentTimers.count))
        self.view.alpha = 0.95

    }

public class TimerObject{
    var alreadySet = false
    var isRunning = false
    var timer = NSTimer()
    var timeDuration = Int()
    var timerString = String()
    var doneString = String()
    let notification = UILocalNotification()

    init(timeDuration: Int, timerString: String, doneString: String){
        self.timeDuration = timeDuration
        self.timerString = timerString
        self.doneString = doneString
        notification.alertBody = doneString
    }
}