Imports System.IO 'import the input and output features
Public Class DueDates 'due dates form
    Dim lineCount As Integer 'The full amount of records in the file
    Dim rowIndex As Integer 'The currently selected row of the datagrid
    Private Sub fillGrid() 'fills the datagrud
        Dim encryption As New clsEncryption 'instantiate the encryption class
        Dim validation As New clsValidation 'instantiate the validation class
        Dim record1 As String 'record for individual borrowings
        Dim fields1() As String 'fields in the record
        Dim record2 As String 'record for borrowing data
        Dim fields2() As String 'fields in the record
        Dim validated As Boolean = True 'is data validated
        Dim searchID As String 'ID being searched for
        Dim searchBorrowingID As String 'borrowingID being searched for
        lineCount = 0
        If validation.presenceCheck(txt_customerID.Text) = True And txt_customerID.Text <> "CustomerID" Then 'validation
            searchID = txt_customerID.Text
        Else
            validated = False 'validation not met
        End If
        If validated = True Then 'if validation met
            Dim sr1 As New StreamReader("individualBorrowings.txt") 'stream reader of individual borrowings
            While sr1.Peek() >= 0 'check every indvidual borrowing for ones with the correct customerID to get a borrowing ID
                record1 = encryption.decrypt(sr1.ReadLine) 'decrypt record from file
                fields1 = record1.Split(",") 'fields in record
                If fields1(1) = searchID Then 'if the search ID is the record ID
                    searchBorrowingID = fields1(0) 'store the borrowingID
                    Dim sr2 As New StreamReader("borrowingData.txt") 'Stream reader of the borrowingData file
                    While sr2.Peek() >= 0 'display the details of the borrowingID
                        record2 = encryption.decrypt(sr2.ReadLine) 'decrypt record
                        fields2 = record2.Split(",") 'split record into fields
                        If fields2(0) = searchBorrowingID Then 'if the borrowingID is found
                            Dim index = dgv_dueDates.Rows.Add 'the next row to add to
                            dgv_dueDates.Rows(index).SetValues(fields2) 'set the row
                            lineCount = lineCount + 1 'increment the linecount to show all rows that have been stored
                        End If
                    End While
                    sr2.Close() 'close the stream reader
                End If
            End While
            sr1.Close() 'close the stream writer
            dgv_dueDates.RowHeadersVisible = False 'Removes the symbols by the rows
            dgv_dueDates.ClearSelection() 'Removes the blue selection box
            dgv_dueDates.Rows(lineCount - 1).Selected = True 'select the final record in the datagrid
            rowIndex = lineCount - 1
        Else
            MsgBox("Must meet validation requirements") 'notify user
        End If
        txt_customerID.Text = "CustomerID" 'reset text boxes
    End Sub
    Private Sub DueDates_Load(sender As Object, e As EventArgs) Handles MyBase.Load
        Me.CenterToScreen() 'centre form to screen
        Dim startupPath As String 'stores the location the program is running
        startupPath = Application.StartupPath
        pbx_logo.ImageLocation = startupPath & "\PennardLibraryLogo.png" 'set image locations
        pbx_back.ImageLocation = startupPath & "\Arrow.png"
        If levelOfAccess = 3 Then
            Me.BackColor = Color.FromArgb(247, 220, 143) 'For admins use yellow
        End If
        If levelOfAccess = 2 Then
            Me.BackColor = Color.FromArgb(140, 227, 245) 'For librarians use a blue background instead of the standard green
        End If
        If levelOfAccess = 1 Then
            Me.BackColor = Color.FromArgb(163, 255, 166) 'For customers use standard green
        End If
    End Sub
    Private Sub pbx_back_Click(sender As Object, e As EventArgs) Handles pbx_back.Click
        Dim MainMenu As New MainMenu 'instantiate the main menu form
        MainMenu.Show() 'show the new form
        Me.Close()  'close the current form
    End Sub
    Private Sub pbx_back_MouseHover(sender As Object, e As EventArgs) Handles pbx_back.MouseHover
        Dim startupPath As String 'stores the location the program is running
        startupPath = Application.StartupPath
        pbx_back.ImageLocation = startupPath & "\ArrowRollover.png" 'rollover image
    End Sub

    Private Sub pbx_back_MouseLeave(sender As Object, e As EventArgs) Handles pbx_back.MouseLeave
        Dim startupPath As String 'stores the location the program is running
        startupPath = Application.StartupPath
        pbx_back.ImageLocation = startupPath & "\Arrow.png" 'rollover image
    End Sub

    Private Sub btn_view_Click(sender As Object, e As EventArgs) Handles btn_view.Click
        fillGrid() 'fill the data grid
    End Sub

    Private Sub txt_customerID_MouseClick(sender As Object, e As MouseEventArgs) Handles txt_customerID.MouseClick
        If txt_customerID.Text = "CustomerID" Then 'if the text is the starting text
            txt_customerID.Text = "" 'clear the textbox
        End If
    End Sub
    Private Sub btn_first_Click(sender As Object, e As EventArgs) Handles btn_first.Click
        dgv_dueDates.ClearSelection()
        dgv_dueDates.Rows(0).Selected = True 'gp back to the first record
        rowIndex = 0
    End Sub

    Private Sub btn_previous_Click(sender As Object, e As EventArgs) Handles btn_previous.Click
        dgv_dueDates.ClearSelection()
        If rowIndex = 0 Then
            MsgBox("You are already looking at the first record")
        Else
            rowIndex = rowIndex - 1
            dgv_dueDates.Rows(rowIndex).Selected = True 'go one record back unless you are at the fist one already
        End If
    End Sub

    Private Sub btn_next_Click(sender As Object, e As EventArgs) Handles btn_next.Click
        dgv_dueDates.ClearSelection()
        If rowIndex = lineCount - 1 Then
            MsgBox("You are already looking at the last record")
        Else
            rowIndex = rowIndex + 1
            dgv_dueDates.Rows(rowIndex).Selected = True 'go on record forwards unless you are at the last one already
        End If
    End Sub

    Private Sub btn_last_Click(sender As Object, e As EventArgs) Handles btn_last.Click
        dgv_dueDates.ClearSelection()
        dgv_dueDates.Rows(lineCount - 1).Selected = True 'go to the last record stored
        rowIndex = lineCount - 1
    End Sub
End Class