Imports System.Data.SqlClient
Imports DigitalData.Modules.Base.IDB
Imports DigitalData.Modules.Database
Imports DigitalData.Modules.Database.MSSQLServer.TransactionMode
Imports DigitalData.Modules.Logging

Namespace Methods.IDB.CheckInOutFile
    Public Class CheckInOutFileMethod
        Inherits BaseMethod

        Private ReadOnly Connection As SqlConnection
        Private ReadOnly Transaction As SqlTransaction

        Public Sub New(pLogConfig As LogConfig, pDatabaseIDB As MSSQLServer, pDatabaseECM As MSSQLServer, pGlobalState As GlobalState)
            MyBase.New(pLogConfig, pDatabaseIDB, pDatabaseECM, pGlobalState)

            Connection = DatabaseIDB.GetConnection()
            Transaction = Connection.BeginTransaction()
        End Sub

        Public Function Run(pData As CheckInOutFileRequest) As CheckInOutFileResponse
            Try
                Dim oResult = False

                If pData.Action = CheckInOutFileAction.CheckOut Then
                    oResult = CheckOutFile(pData.ObjectId, pData.User.UserName, pData.Comment)

                ElseIf pData.Action = CheckInOutFileAction.CheckIn Then
                    oResult = CheckInFile(pData.ObjectId, pData.User.UserName)

                Else
                    LogAndThrow("Invalid action supplied!")

                End If

                If oResult = False Then
                    LogAndThrow($"Could not Check In/Out file [{pData.ObjectId}]!")
                End If

                Return New CheckInOutFileResponse(pData.ObjectId)
            Catch ex As Exception
                Logger.Warn("Error occurred while checkin in/out file!")
                Logger.Error(ex)

                Logger.Info("Rolling back transaction.")
                Transaction?.Rollback()

                Return New CheckInOutFileResponse(ex)

            End Try
        End Function

        Private Function CheckOutFile(pObjectId As Long, pUsername As String, pComment As String) As Boolean
            Try
                Dim oTable = TestFileIsCheckedOut(pObjectId)
                If oTable Is Nothing Then
                    Return False
                End If

                ' If there are rows, the file is already checked out (either by the calling user or somebody else)
                If oTable.Rows.Count > 0 Then
                    ' TODO: Return the person who has this file checked out
                    Return False
                End If

                Dim oSQL = $"INSERT INTO TBIDB_OBJECT_CHECK_IN_OUT (IDB_OBJ_ID, CHECKED_OUT_WHEN, COMMENT, ADDED_WHO) 
                        VALUES ({pObjectId}, GETDATE(), '{pComment}', '{pUsername}')"
                Return DatabaseIDB.ExecuteNonQuery(oSQL)

            Catch ex As Exception
                Logger.Error(ex)
                Return False

            End Try
        End Function

        Private Function CheckInFile(pObjectId As Long, pUsername As String) As Boolean
            Try
                Dim oTable = TestFileIsCheckedOut(pObjectId)
                If oTable Is Nothing Then
                    Return False
                End If

                ' If there are no rows, the file is not checked out
                If oTable.Rows.Count > 0 Then
                    Return True
                End If

                Dim oSQL = $"UPDATE TBIDB_OBJECT_CHECK_IN_OUT 
                        SET CHECKED_IN_WHEN = GETDATE(), CHANGED_WHO = '{pUsername}'
                        WHERE IDB_OBJ_ID = {pObjectId} AND ADDED_WHO = '{pUsername}' AND CHECKED_IN_WHEN IS NULL"
                Return DatabaseIDB.ExecuteNonQuery(oSQL)

            Catch ex As Exception
                Logger.Error(ex)
                Return False

            End Try
        End Function

        Private Function TestFileIsCheckedOut(pObjectId As Long) As DataTable
            Try
                Dim oSqlCheck = $"SELECT * FROM TBIDB_OBJECT_CHECK_IN_OUT WHERE IDB_OBJ_ID = {pObjectId} AND CHECKED_IN_WHEN IS NULL"
                Dim oTable As DataTable = DatabaseIDB.GetDatatable(oSqlCheck)

                Return oTable
            Catch ex As Exception
                Logger.Error(ex)
                Return Nothing

            End Try
        End Function


    End Class

End Namespace