Imports DigitalData.Modules.Logging
Imports DigitalData.Modules.Filesystem
Imports Limilabs.Mail
Imports Limilabs.Client.IMAP
Imports Limilabs.Mail.MIME

Public Class Email2
    Private ReadOnly Logger As Logger
    Private ReadOnly LogConfig As LogConfig
    Private ReadOnly FileEx As Filesystem.File

    Public Sub New(pLogConfig As LogConfig)
        LogConfig = pLogConfig
        Logger = pLogConfig.GetLogger()
        FileEx = New Filesystem.File(pLogConfig)
    End Sub

    Public Enum EmailSecurity
        SSL
        STARTTLS
    End Enum

    Private Function Get_PortForSecurityOption(pSecurity As EmailSecurity) As Integer
        Select Case pSecurity
            Case EmailSecurity.SSL
                Return 993

            Case EmailSecurity.STARTTLS
                Return 143

            Case Else
                Return 0
        End Select
    End Function

    Public Function Test_Login(pServer As String, pUsername As String, pPassword As String, pSecurity As EmailSecurity, Optional pFolder As String = "Inbox", Optional pPort As Integer = 0) As Boolean
        Logger.Debug("Testing Login to Server [{0}:{1}] with user [{2}]", pServer, pPort, pUsername)

        Try
            Using oClient As New Imap()
                Logger.Debug("Connecting to IMAP server [{0}]", pServer)

                Dim oPort As Integer = pPort
                If oPort = 0 Then
                    oPort = Get_PortForSecurityOption(pSecurity)
                End If

                If pSecurity = EmailSecurity.SSL Then
                    oClient.ConnectSSL(pServer, oPort)
                ElseIf pSecurity = EmailSecurity.STARTTLS Then
                    oClient.Connect(pServer, oPort)
                    oClient.StartTLS()
                Else
                    Throw New ArgumentOutOfRangeException("Security")
                End If

                Logger.Debug("Logging in with user [{0}]", pUsername)
                oClient.UseBestLogin(pUsername, pPassword)

                Logger.Debug("Fetching Inbox")
                Dim oStatus As FolderStatus = oClient.SelectInbox()

                Logger.Debug("Test finished!")
                oClient.Close()
            End Using

            Return True
        Catch ex As Exception
            Logger.Warn("Login failed for server [{0}:{1}] with user [{2}]!", pServer, pPort, pUsername)
            Logger.Error(ex)

            Return False
        End Try
    End Function

    Public Function Get_Messages(pServer As String, pUsername As String, pPassword As String, pSecurity As EmailSecurity, Optional pFolder As String = "Inbox", Optional pPort As Integer = 0) As List(Of IMail)
        Logger.Debug("Fetching Messages from Server [{0}:{1}] with user [{2}]", pServer, pPort, pUsername)

        Dim oMails As New List(Of IMail)

        Try
            Using oClient As New Imap()
                Logger.Debug("Connecting to IMAP server [{0}]", pServer)

                Dim oPort As Integer = pPort
                If oPort = 0 Then
                    oPort = Get_PortForSecurityOption(pSecurity)

                End If

                If pSecurity = EmailSecurity.SSL Then
                    oClient.ConnectSSL(pServer, oPort)

                ElseIf pSecurity = EmailSecurity.STARTTLS Then
                    oClient.Connect(pServer, oPort)
                    oClient.StartTLS()

                Else
                    Throw New ArgumentOutOfRangeException("Security")

                End If

                Logger.Debug("Logging in with user [{0}]", pUsername)
                oClient.UseBestLogin(pUsername, pPassword)

                Logger.Debug("Fetching Folder [{0}]", pFolder)
                Dim oStatus As FolderStatus = oClient.Select(pFolder)

                Logger.Debug("Fetching Unseen UUIDs")
                Dim oUUIDs As List(Of Long) = oClient.Search(Flag.Unseen)
                Dim oMailBuilder As New MailBuilder()

                Logger.Debug("Fetching Unseen Mails")
                For Each oUUID As Long In oUUIDs
                    Dim oEmlFile As Byte() = oClient.GetMessageByUID(oUUID)
                    Dim oEmail As IMail = oMailBuilder.CreateFromEml(oEmlFile)
                    oMails.Add(oEmail)

                Next

                Logger.Debug("Emails fetched!")
                oClient.Close()
            End Using

            Return oMails

        Catch ex As Exception
            Logger.Warn("Login failed for server [{0}:{1}] with user [{2}]!", pServer, pPort, pUsername)
            Logger.Error(ex)
            Return New List(Of IMail)

        End Try
    End Function

    Public Function Get_Message(pServer As String, pUsername As String, pPassword As String, pSecurity As EmailSecurity, pMessageId As String, Optional pFolder As String = "Inbox", Optional pPort As Integer = 0) As IMail
        Logger.Debug("Fetching Message [{0}] from Server [{1}:{2}] with user [{3}]", pMessageId, pServer, pPort, pUsername)

        Dim oMail As IMail = Nothing

        Try
            Using oClient As New Imap()
                Logger.Debug("Connecting to IMAP server [{0}]", pServer)

                Dim oPort As Integer = pPort
                If oPort = 0 Then
                    oPort = Get_PortForSecurityOption(pSecurity)

                End If

                If pSecurity = EmailSecurity.SSL Then
                    oClient.ConnectSSL(pServer, oPort)

                ElseIf pSecurity = EmailSecurity.STARTTLS Then
                    oClient.Connect(pServer, oPort)
                    oClient.StartTLS()

                Else
                    Throw New ArgumentOutOfRangeException("Security")

                End If

                Logger.Debug("Logging in with user [{0}]", pUsername)
                oClient.UseBestLogin(pUsername, pPassword)

                Logger.Debug("Fetching Inbox")
                Dim oStatus As FolderStatus = oClient.Select(pFolder)

                Logger.Debug("Fetching UUIDs")
                Dim oUUIDs As List(Of Long) = oClient.Search(Flag.All)
                Dim oMailBuilder As New MailBuilder()

                Dim oInfos As List(Of MessageInfo) = oClient.GetMessageInfoByUID(oUUIDs)

                Logger.Debug("Fetching Unseen Mails")
                For Each oInfo As MessageInfo In oInfos
                    If oInfo.Envelope.MessageID = pMessageId Then
                        Dim oMailData As Byte() = oClient.GetMessageByUID(oInfo.UID)
                        oMail = oMailBuilder.CreateFromEml(oMailData)

                        Exit For
                    End If
                Next

                Logger.Debug("Emails fetched!")
                oClient.Close()
            End Using

            Return oMail

        Catch ex As Exception
            Logger.Warn("Login failed for server [{0}:{1}] with user [{2}]!", pServer, pPort, pUsername)
            Logger.Error(ex)
            Return New List(Of IMail)

        End Try
    End Function

    Public Function Remove_AttachmentsFromEmail(pFileName As String) As String
        Try
            Dim oTempFileName As String = IO.Path.GetTempFileName()
            Dim oMailBuilder As New MailBuilder()
            Dim oMail = oMailBuilder.CreateFromEmlFile(pFileName)

            oMail.RemoveAttachments()
            oMail.Save(oTempFileName)

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

            Return Nothing
        End Try
    End Function

    Public Function Save_AttachmentsToDisk(pFileName As String) As List(Of String)
        Try
            Dim oAttachmentPaths As New List(Of String)
            Dim oMailBuilder As New MailBuilder()
            Dim oMail = oMailBuilder.CreateFromEmlFile(pFileName)
            Dim oTempPath As String = IO.Path.GetTempPath()

            If oMail.Attachments.Count = 0 Then
                Return New List(Of String)
            End If

            For Each oAttachment As MimeData In oMail.Attachments
                Dim oPath As String = IO.Path.Combine(oTempPath, oAttachment.SafeFileName)
                Dim oVersionedPath As String = FileEx.GetVersionedFilename(oPath)

                oAttachment.Save(oVersionedPath)
                oAttachmentPaths.Add(oVersionedPath)
            Next

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

            Return New List(Of String)
        End Try
    End Function
End Class