Imports System.IO
Imports System.Text
Imports System.Threading.Tasks
Imports Zebra.Sdk.Comm
Imports Zebra.Sdk.Printer
Imports Zebra.Sdk.Printer.Discovery

Class ZebraPrinter

   Private m_FileLog As String
   Private m_Values As New Dictionary(Of String, String)
   Private m_LabelBytes As Byte()
   Private m_printerConnection As Connection = Nothing
   Private m_sDataRoot As String
   Private m_Waiting As Boolean = True

   ' dichiarazione funzione per lettura file ini
   Private Declare Auto Function GetPrivateProfileString Lib "kernel32" (
            ByVal lpAppName As String,
            ByVal lpKeyName As String,
            ByVal lpDefault As String,
            ByVal lpReturnedString As StringBuilder,
            ByVal nSize As Integer,
            ByVal lpFileName As String) As Integer


   ' inizilizzo il file di log inserendo la data dell'esecuzione
   Sub InitLog()
      ' Impostazione path radice per i dati
      m_sDataRoot = System.AppDomain.CurrentDomain.BaseDirectory
      Dim sb = New StringBuilder(500)
      If GetPrivateProfileString("Data", "DataRoot", "", sb, sb.Capacity, m_sDataRoot & "DataRoot.ini") = 0 Then
         m_sDataRoot = System.AppDomain.CurrentDomain.BaseDirectory
      Else
         m_sDataRoot = sb.ToString
      End If
      m_FileLog = m_sDataRoot & "\ZebraPrinterUtilityLog.txt"
      If Not File.Exists(m_FileLog) Then
         Try
            File.Create(m_FileLog).Close()
         Catch ex As Exception
         End Try
      End If
      Try
         Dim sMessage As StreamWriter = File.AppendText(m_FileLog)
         sMessage.WriteLine(DateTime.Now.ToString)
         sMessage.Close()
      Catch ex As Exception
      End Try

   End Sub

   ' Funzione per scrivere nel file di Log
   Sub EmitLog(sLine As String)
      Dim sMessage As StreamWriter = File.AppendText(m_FileLog)
      sMessage.WriteLine(sLine)
      sMessage.Close()
   End Sub

   ' collego la stampante
   Friend Function ConnectPrinter() As Boolean
      Try
         Dim discoPrinters As List(Of DiscoveredPrinterDriver) = UsbDiscoverer.GetZebraDriverPrinters()
         m_printerConnection = New DriverPrinterConnection(discoPrinters(0).PrinterName)
         Return True
      Catch ex As ConnectionException
         EmitLog("Printer connection error: " & ex.Message)
         Return False
      End Try
   End Function

   ' creo e stampo l'etichetta (ricevo il nome del template da usare)
   Public Async Sub Print(FilePath As String)
      Await Task.Run(Async Function()

                        Try
                           ' Connecting...
                           m_printerConnection.Open()
                           EmitLog("Connessione stampante: APERTA")
                           ' Sending Data...
                           Dim LabelFile As String = File.ReadAllText(FilePath)
                           For Each Variable In m_Values
                              LabelFile = LabelFile.Replace(Variable.Key, Variable.Value)
                           Next
                           Dim LabelBytes As Byte() = Encoding.UTF8.GetBytes(LabelFile)
                           Await Task.Delay(200)
                           ' stampo etichetta
                           m_printerConnection.Write(LabelBytes)
                           m_Waiting = False
                           EmitLog("Etichetta pronta")
                        Catch __unusedConnectionException1__ As ConnectionException
                           EmitLog(__unusedConnectionException1__.ToString)
                           ' Communications Error
                        Catch __unusedZebraPrinterLanguageUnknownException2__ As ZebraPrinterLanguageUnknownException
                           EmitLog(__unusedZebraPrinterLanguageUnknownException2__.ToString)
                        End Try

                        ' Chiudo la connessione
                        Try
                           'Threading.Thread.Sleep(500)
                           Threading.Thread.Sleep(200)
                           ' Disconnecting...
                           If m_printerConnection IsNot Nothing Then
                              m_printerConnection.Close()
                              EmitLog("Connessione stampante: CHIUSA")
                              Threading.Thread.Sleep(1000)
                           End If
                           ' Not Connected
                        Catch __unusedConnectionException1__ As ConnectionException
                           EmitLog(__unusedConnectionException1__.ToString)
                        End Try

                     End Function)
   End Sub


   ' Lettura file ini
   Private Function ReadValue(FilePath As String) As Boolean
      ' verifico che il file esiste
      If Not File.Exists(FilePath) Then
         EmitLog("File '" & FilePath & "' non esiste.")
         Return False
      End If

      Dim sb = New StringBuilder(500)
      Dim Index As Integer = 1
      Dim nResult As Integer = -1
      ' leggo l'elenco delle variabili
      While nResult <> 0
         Try
            nResult = GetPrivateProfileString("Main", "Var" & Index.ToString, "", sb, sb.Capacity, FilePath)
         Catch ex As Exception
            EmitLog(ex.ToString)
            Index = Index + 1
            Continue While
         End Try
         Dim sItems As String() = sb.ToString.Split(","c)
         If sItems.Count = 2 Then
            m_Values.Add(sItems(0).Trim, sItems(1).Trim)
         End If
         Index = Index + 1
      End While

      EmitLog("Dati caricati")
      Return True
   End Function

   Sub New(args As String())

      InitLog()
      ConnectPrinter()

      ' verifico che il numero di argomenti sia superiore a 2 (migliorare l'interpretazione dell'errore)
      If args.Length < 2 Then
         EmitLog("Non sono stati esplicictati tutti i file")
         Return
      End If

      EmitLog("File template: " & args(0))
      ' verifico che l'estensione del file sia corretta
      If Path.GetExtension(args(0)) <> ".prn" Then
         EmitLog("Estensione file template non corretta, diversa da .prn")
         Return
      End If
      ' verifico che il file esiste
      If Not File.Exists(args(0)) Then
         EmitLog("File '" & args(0) & "' non esiste.")
      End If

      EmitLog("File dati: " & args(1))
      ' verifico che l'estensione del file sia corretta
      If Path.GetExtension(args(1)) <> ".ini" Then
         EmitLog("Estensione file dati non corretta, diversa da .ini")
         Return
      End If

      ' leggo l'elenco dei dati da stampare
      If Not ReadValue(args(1)) Then Return
      ' stampo etichetta
      Print(args(0))

      ' metto il programmma in attesa
      Dim nCiclo As Integer = 0
      While m_Waiting And nCiclo < 6
         Threading.Thread.Sleep(1000)
         nCiclo += 1
      End While
   End Sub


End Class