Imports System.Data.SqlClient

Public Class DB
    Private _connstring
    Private _db

    Public FormId
    Public ControlId
    Public RecordId
    Public Username As String = "BrainpoolImporter"

    Public Sub New(connectionString As String, dbname As String)
        _connstring = connectionString
        _db = dbname
    End Sub

    Public Function formatTable(table As String) As String
        Return String.Format("[{0}].[dbo].[{1}]", _db, table)
    End Function

    Public Function GetFormId() As Integer
        Dim sql = String.Format("SELECT GUID FROM {0} WHERE NAME = '{1}'", Me.formatTable("TBPMO_FORM"), "Marken")
        Return Me.Scalar(sql)
    End Function

    Public Function GetControlId(formId As Integer, Optional name As String = "ApplicationNumber") As Integer
        Dim sql = String.Format("SELECT GUID FROM {0} WHERE NAME = '{1}' AND FORM_ID = {2}", Me.formatTable("TBPMO_CONTROL"), name, formId)
        Return Me.Scalar(sql)
    End Function

    Public Function GetProperty(m As Mark, propertyName As String) As Object
        Dim value = CallByName(m, propertyName, CallType.Get)
        If (value = Nothing) Then
            value = DBNull.Value
        End If

        Return value
    End Function

    Public Function GetRecordId(controlId As Integer, applicationNumber As String) As Integer
        Dim sql = String.Format("SELECT RECORD_ID FROM {0} WHERE CONTROL_ID = {1} AND VALUE = '{2}'", Me.formatTable("TBPMO_CONTROL_VALUE"), controlId, applicationNumber)
        Return Me.Scalar(sql)
    End Function

    Public Function InsertRecord(formId As Integer)
        Dim sql = String.Format("INSERT INTO {0} (FORM_ID, ADDED_WHO) VALUES ({1}, '{2}')", Me.formatTable("TBPMO_RECORD"), formId, Username)
        Me.NonQuery(sql)
        Return Me.Scalar("SELECT MAX(GUID) FROM TBPMO_RECORD")
    End Function

    Public Function InsertValue(controlId As Integer, recordId As Integer, value As Object)
        Dim table = Me.formatTable("TBPMO_CONTROL_VALUE")
        Dim sql = String.Format("INSERT INTO {0} (CONTROL_ID, RECORD_ID, VALUE) VALUES ({1}, {2}, '{3}')", table, controlId, recordId, value)
        Me.NonQuery(sql)
        Return Me.Scalar(String.Format("SELECT MAX(GUID) FROM {0} WHERE CONTROL_ID = {1}", table, controlId))
    End Function

    Public Sub UpdateValue(controlId As Integer, recordId As Integer, value As Object)
        Dim table = Me.formatTable("TBPMO_CONTROL_VALUE")
        Dim sql = String.Format("UPDATE {0} SET VALUE = '{1}' WHERE CONTROL_ID = {2} AND RECORD_ID = {3}", table, value, controlId, recordId)
        Me.NonQuery(sql)
    End Sub

    Public Function IsEqual(controlId As Integer, recordId As Integer, valueToCompare As Object)
        Dim table = Me.formatTable("TBPMO_CONTROL_VALUE")
        Dim sql = String.Format("SELECT VALUE FROM {0} WHERE CONTROL_ID = {1} AND RECORD_ID = {2}", table, controlId, recordId)
        Dim value = Me.Scalar(sql)

        If (IsDBNull(valueToCompare) Xor IsDBNull(value)) Then
            Return False
        End If

        Return value = valueToCompare
    End Function

    Public Function Scalar(queryString As String)
        Dim conn As New SqlConnection(_connstring)
        Dim cmd As New SqlCommand(queryString, conn)
        Dim result

        Try
            conn.Open()

            result = cmd.ExecuteScalar()
            conn.Dispose()
            conn.Close()

            Return result
        Catch ex As Exception
            Throw New Exception(String.Format("Error while executing SQL Scalar-Query ({0}): {1}", queryString, ex.Message))
        End Try
    End Function


    Public Function NonQuery(queryString As String)
        Dim conn As New SqlConnection(_connstring)
        Dim cmd As New SqlCommand(queryString, conn)

        Try
            conn.Open()

            cmd.ExecuteNonQuery()
            conn.Dispose()
            conn.Close()

            Return True
        Catch ex As Exception
            Throw New Exception(String.Format("Error while executing SQL Non-Query ({0}): {1}", queryString, ex.Message))
        End Try
    End Function

    Public Function QueryTable(queryString As String) As DataTable
        Try
            Dim conn As New SqlConnection(_connstring)
            Dim cmd As New SqlCommand(queryString, conn)
            Dim adapter As New SqlDataAdapter(cmd)
            Dim dt As New DataTable()

            conn.Open()
            adapter.Fill(dt)
            conn.Dispose()
            conn.Close()

            Return dt
        Catch ex As Exception
            Throw New Exception(String.Format("Error while executing SQL Query ({0}): {1}", queryString, ex.Message))
        End Try
    End Function

End Class