'----------------------------------------------------------
' Lab 2 (A201)
' CoinCounter
' 
' This program will ask the user to enter a number coins into
' appropriate textboxes, and then will calculate the total 
' dollars and cents.
' Prior to calculating the totals, the program will also perform
' some error checking to make sure the values in the textboxes 
' represent integer numbers.

Option Strict On
Option Explicit On 

'------------------------------------------------
Public Class Form1

    '------------------------------------------------
    Private Sub BtnQuit_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnQuit.Click

        Application.Exit()        ' same as saying Me.Close()

    End Sub

    '------------------------------------------------
    Private Sub BtnClear_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnClear.Click
        ' Clear out the textboxes
        TxtBxQuarters.Text = ""
        TxtBxDimes.Text = ""
        TxtBxNickels.Text = ""
        TxtBxPennies.Text = ""
        TxtBxDollars.Text = ""
        TxtBxCents.Text = ""
    End Sub

    '------------------------------------------------
    Private Sub BtnCalculate_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnCalculate.Click

        Dim Total As Integer = 0              ' Declare an integer variable
        VerifyTextboxes()                     ' ERROR Checking:  Verify the content of textboxes

        Total = CInt(TxtBxQuarters.Text) * 25 + CInt(TxtBxDimes.Text) * 10 + CInt(TxtBxNickels.Text) * 5 + CInt(TxtBxPennies.Text) * 1
        TxtBxDollars.Text = CStr(Total \ 100)      ' Integer division, and implicit type conversion
        TxtBxCents.Text = CStr(Total Mod 100)      ' Remainder, and implicit type conversion


    End Sub

    '------------------------------------------------
    ' Check the content of each textbox, make sure the 
    ' content is numeric, if it not warn the user by
    ' changing the color of the textbox to red, then
    ' display a message explaining what the problem is,
    ' and finally replace the content with a zero (0) and
    ' change the color of the textbox back to white.
    Private Sub VerifyTextboxes()

        If IsNumeric(TxtBxQuarters.Text) Then
            TxtBxQuarters.Text = CStr(Int(TxtBxQuarters.Text))   ' convert to integer and truncate decimals
        Else
            TxtBxQuarters.BackColor = System.Drawing.Color.Red
            MessageBox.Show("Number of quarters must be expressed as an integer")
            TxtBxQuarters.Text = "0"
            TxtBxQuarters.BackColor = System.Drawing.Color.White
        End If

        If IsNumeric(TxtBxDimes.Text) Then
            TxtBxDimes.Text = CStr(Int(TxtBxDimes.Text))
        Else
            TxtBxDimes.BackColor = System.Drawing.Color.Red
            MessageBox.Show("Number of dimes must be expressed as an integer")
            TxtBxDimes.Text = "0"
            TxtBxDimes.BackColor = System.Drawing.Color.White
        End If

        If IsNumeric(TxtBxNickels.Text) Then
            TxtBxNickels.Text = CStr(Int(TxtBxNickels.Text))
        Else
            TxtBxNickels.BackColor = System.Drawing.Color.Red
            MessageBox.Show("Number of nickels must be expressed as an integer")
            TxtBxNickels.Text = "0"
            TxtBxNickels.BackColor = System.Drawing.Color.White
        End If

        If IsNumeric(TxtBxPennies.Text) Then
            TxtBxPennies.Text = CStr(Int(TxtBxPennies.Text))
        Else
            TxtBxPennies.BackColor = System.Drawing.Color.Red
            MessageBox.Show("Number of pennies must be expressed as an integer")
            TxtBxPennies.Text = "0"
            TxtBxPennies.BackColor = System.Drawing.Color.White
        End If
    End Sub
End Class