Imports System.Speech.Recognition
Imports System.Speech.Synthesis

Namespace SimpleSpeech
    Public Class SpeechHandle
#Region "Declarations"
        Private _Commands As New List(Of String)
        Private _Voice As String
        Private _Volume As Integer

        Private spoken_text As String
        Private spoken_sentence As String
        Private speak As New System.Speech.Synthesis.SpeechSynthesizer
        Private recognizer As New SpeechRecognitionEngine()

        Private LastSpokenText As String
        Private allowrec As Boolean = True

        Private Dictrecognizer As New SpeechRecognitionEngine
#End Region

#Region "Events"
        Public Event Recognized(sender As Object, e As SpeechRecognizedEventArgs)
        Public Event TextSpoken(sender As Object, e As TextSpokenEventArgs)
        Public Event CommandsLoaded(sender As Object, e As CommandEventArgs)
        Public Event CommandsUnloaded(sender As Object, e As CommandEventArgs)
        Public Event DictationRecognized(sender As Object, e As DictationSpeechRecognizedEventArgs)
#End Region

        Public Sub New()
            AddHandler recognizer.LoadGrammarCompleted, AddressOf recognizer_LoadGrammarCompleted
            AddHandler speak.SpeakCompleted, AddressOf speak_completed
            AddHandler recognizer.SpeechRecognized, AddressOf recognizer_SpeechRecognized
            AddHandler Dictrecognizer.SpeechRecognized, AddressOf dictationrecognizer_SpeechRecognized
        End Sub

        Public Property Volume As String
            Get
                Return _Volume
            End Get
            Set(Volume As String)
                _Volume = Volume
                speak.Volume = Volume
            End Set
        End Property

        Public Property Voice As String
            Get
                Return _Voice
            End Get
            Set(Name As String)
                _Voice = Name
            End Set
        End Property

        Public Function GetVoices()
            Dim voices As New List(Of String)
            For Each instVoice In speak.GetInstalledVoices()
                voices.Add(instVoice.VoiceInfo.Name)
            Next

            Return voices
        End Function

        Public Sub LoadCommands(ByVal Commands As List(Of String))
            _Commands = Commands

            recognizer.UnloadAllGrammars()
            recognizer.LoadGrammar(CreateGrammar(_Commands))
        End Sub

        Public Sub UnloadCommands()
            _Commands.Clear()

            recognizer.UnloadAllGrammars()
        End Sub

        Public Function StartRecognize() As Boolean
            Try
                recognizer.SetInputToDefaultAudioDevice()
                recognizer.RecognizeAsync(RecognizeMode.Multiple)
                Return True
            Catch ex As Exception
                Return False
            End Try
        End Function

        Public Function StopRecognize() As Boolean
            Try
                recognizer.RecognizeAsyncCancel()
                recognizer.SetInputToNull()
                Return True
            Catch ex As Exception
                Return False
            End Try
        End Function

        Public Sub SpeakText(ByVal Text As String)
            allowrec = False

            If _Voice = "" Then
                speak.SelectVoice(speak.GetInstalledVoices().Item(0).VoiceInfo.Name)
            Else
                speak.SelectVoice(_Voice)
            End If

            speak.SpeakAsync(Text)
            LastSpokenText = Text
        End Sub

        Public Sub StopSpeak()
            speak.SpeakAsyncCancelAll()
        End Sub

        Private Function CreateGrammar(ByVal Words As List(Of String)) As Grammar
            Dim builder As New GrammarBuilder()

            Dim Text As New Choices(Words.ToArray)

            builder.Append(Text)

            Dim Grammar As New Grammar(builder)
            Grammar.Name = "Grammar"

            Return Grammar
        End Function

        Private Sub recognizer_SpeechRecognized(ByVal sender As Object, ByVal e As System.Speech.Recognition.SpeechRecognizedEventArgs)
            If allowrec = True Then
                spoken_text = e.Result.Text

                For Each com In _Commands
                    If e.Result.Text = com Then
                        RaiseEvent Recognized(Me, New SpeechRecognizedEventArgs(com))
                    End If
                Next
            End If
        End Sub

        Private Sub speak_completed(ByVal sender As Object, ByVal e As SpeakCompletedEventArgs)
            RaiseEvent TextSpoken(Me, New TextSpokenEventArgs(LastSpokenText))
            allowrec = True
        End Sub

        Private Sub recognizer_LoadGrammarCompleted(sender As Object, e As System.Speech.Recognition.LoadGrammarCompletedEventArgs)
            If e.Grammar.Loaded = True Then
                RaiseEvent CommandsLoaded(Me, New CommandEventArgs(_Commands))
            Else
                RaiseEvent CommandsUnloaded(Me, New CommandEventArgs(_Commands))
            End If
        End Sub

        'dictation
        Dim standardvalue As New List(Of String)
        Public Function StartdictationRecognize(Optional ByVal ExtraCommands As List(Of String) = Nothing) As Boolean
            Try
                Dictrecognizer.SetInputToDefaultAudioDevice()

                Dim dictation As Grammar = New DictationGrammar()
                dictation.Name = "Dictation"

                If ExtraCommands IsNot Nothing Then
                    Dictrecognizer.LoadGrammar(CreateGrammar(ExtraCommands))
                End If

                Dictrecognizer.LoadGrammarAsync(dictation)
                Dictrecognizer.RecognizeAsync(RecognizeMode.Multiple)

                Return True
            Catch ex As Exception
                Return False
            End Try
        End Function

        Public Function StopdictationRecognize() As Boolean
            Try
                Dictrecognizer.RecognizeAsyncCancel()
                Dictrecognizer.SetInputToNull()
                Return True
            Catch ex As Exception
                Return False
            End Try
        End Function

        Private Sub dictationrecognizer_SpeechRecognized(sender As Object, e As System.Speech.Recognition.SpeechRecognizedEventArgs)
            If allowrec = True Then
                spoken_sentence = e.Result.Text

                RaiseEvent DictationRecognized(Me, New DictationSpeechRecognizedEventArgs(e.Result.Text))
            End If
        End Sub
    End Class

    Public NotInheritable Class DictationSpeechRecognizedEventArgs
        Inherits EventArgs

        Private _Sent As String

        Friend Sub New(Sentence As String)
            _Sent = Sentence
        End Sub

        Public ReadOnly Property Sentence As String
            Get
                Return _Sent
            End Get
        End Property

    End Class

    Public NotInheritable Class SpeechRecognizedEventArgs
        Inherits EventArgs

        Private _Com As String

        Friend Sub New(Command As String)
            _Com = Command
        End Sub

        Public ReadOnly Property Command As String
            Get
                Return _Com
            End Get
        End Property
    End Class

    Public NotInheritable Class TextSpokenEventArgs
        Inherits EventArgs

        Private _Text As String

        Friend Sub New(Text As String)
            _Text = Text
        End Sub

        Public ReadOnly Property Text As String
            Get
                Return _Text
            End Get
        End Property
    End Class

    Public NotInheritable Class CommandEventArgs
        Inherits EventArgs

        Private _Commands As New List(Of String)

        Friend Sub New(Commands As List(Of String))
            _Commands = Commands
        End Sub

        Public ReadOnly Property Commands As List(Of String)
            Get
                Return _Commands
            End Get
        End Property
    End Class
End Namespace