Module GuessANumber
    Dim _Rnd As Random
    Function IsAnInt(input As String) As Boolean
        Dim output As Integer
        Return Integer.TryParse(input, output)
    End Function
    Function GetNumericInput(prompt As String) As Integer
        Dim val As Integer
        While True
            Console.Write($"{prompt}: ")
            Dim ans = Console.ReadLine()
            If IsAnInt(ans) Then
                val = Integer.Parse(ans)
                Exit While
            End If
            Console.WriteLine("Your entry was not a number.")
        End While
        Return val
    End Function
    Function GetInput(question As String) As String
        Dim ans As String = String.Empty
        While True
            Console.WriteLine($"{question}?")
            ans = Console.ReadLine()
            If Not String.IsNullOrWhiteSpace(ans) Then
                Exit While
            End If
            Console.WriteLine("Your entry seems empty.")
        End While
        Return ans
    End Function
    Function AskToPlayAgain() As Boolean
        Dim answer As Boolean = False
        While True
            Dim ans = GetInput("Would you like to play again? (""YES"" OR ""NO"")").ToUpper()
            If ans = "YES" Or ans = "Y" Then
                answer = True
                Exit While
            ElseIf ans = "NO" Or ans = "N" Then
                answer = False
                Exit While
            End If
            Console.WriteLine("Please respond with ""YES"" or ""NO""")
        End While
        Return answer
    End Function
    Sub Main()
        Console.WriteLine("*** GUESS A NUMBER : Visual Basic ***")
        _Rnd = New Random()
        Dim Running As Boolean = True
        Dim GotMaximumNumber As Boolean = False
        Dim GameOver As Boolean = False
        Dim MaxNumber As Integer = 0
        Dim Answer As Integer = 0
        Dim Tries As Integer = 0
        While Running
            While Not GotMaximumNumber
                MaxNumber = GetNumericInput("Please enter the maximum number you wish to use")
                If MaxNumber > 0 Then
                    GotMaximumNumber = True
                    Answer = _Rnd.Next(1, MaxNumber)
                    GameOver = False
                    Tries = 0
                    Console.WriteLine($"Ok, I am thinking of a number between 1 and {MaxNumber}")
                Else
                    Console.WriteLine("The maximum number should be greater than zero.")
                End If
            End While
            Dim Guess = GetNumericInput($"Guess a number between 1 and {MaxNumber}")
            Tries = Tries + 1
            If Guess > Answer Then
                Console.WriteLine("Too High.")
            ElseIf Guess < Answer Then
                Console.WriteLine("Too Low.")
            Else
                If Tries = 1 Then
                    Console.WriteLine("You got it in 1 try!")
                Else
                    Console.WriteLine($"You got it in {Tries} tries!")
                End If
                GameOver = True
            End If
            If GameOver Then
                Running = AskToPlayAgain()
                If Running Then
                    GotMaximumNumber = False
                End If
            End If
        End While
        Console.WriteLine("Thanks for playing")
        Console.WriteLine("*** GAME OVER ***")
        Console.ReadLine()
    End Sub
End Module