Guessing game written in Swift.

CommandLineGuessingGame

import Foundation

class GuessingGame: NSObject
{
    let name: String?

    init(name: String)
    {
        self.name = name
        super.init()
    }

    convenience init()
    {
        let standardInput = NSFileHandle.fileHandleWithStandardInput()
        print("\nWhat's your name? ")
        let inputData = standardInput.availableData
        let inputString = NSString(data: inputData, encoding: NSUTF8StringEncoding)

        self.init(name: inputString)
    }

    func askQuestionFromStandardInput(question: String) -> String
    {
        print(question + " ")
        let standardInput = NSFileHandle.fileHandleWithStandardInput()
        let inputData = standardInput.availableData
        let inputString = NSString(data: inputData, encoding: NSUTF8StringEncoding).stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())

        return inputString
    }

    func playOneGame()
    {
        playOneGame(name)
    }

    func playOneGame(name: NSString?)
    {
        let randomNumber = Int(arc4random_uniform(100))
        var guess = -1
        var tries = 0

        while ((guess != randomNumber) && (tries < 20))
        {
            let numberString = askQuestionFromStandardInput("\nI'm thinking of a number between 1 and 100. Which number am I thinking of?")
            let number = numberString.toInt()

            if number
            {
                guess = number!
                switch(guess) {
                case randomNumber:
                    println("Congratulations, you win! It took you \(tries) tries.")
                default:
                    var tooHighTooLow = " Too high."
                    if (guess < randomNumber)
                    {
                        tooHighTooLow = " Too low."
                    }
                    println("No, that's not it. \(tooHighTooLow) Try again.")
                    tries++
                }
            }
            else
            {
                println("Invalid input. Please try again.")
            }
        }
        
        if (randomNumber != guess)
        {
            println("You used up all of your tries.")
        }

        let tryAgainResponse = askQuestionFromStandardInput("Would you like to play again? ")
        if (tryAgainResponse.lowercaseString.hasPrefix("y"))
        {
            playOneGame(name)
        }
    }
}

let game = GuessingGame()
game.playOneGame()