Imports Microsoft.VisualBasic
Imports NAudio.Wave
Imports NAudio.Wave.SampleProviders
Public Class LoopStream
    Inherits WaveStream
    Private _sourceStream As WaveStream

    Public Sub New(ByVal sourceStream As WaveStream, Optional ByVal Looping As Boolean = True)
        Me._sourceStream = sourceStream
        Me._enableLooping = Looping
    End Sub

    Public Property _enableLooping As Boolean

    Public Overrides ReadOnly Property WaveFormat As WaveFormat
        Get
            Return _sourceStream.WaveFormat
        End Get
    End Property

    Public Overrides ReadOnly Property Length As Long
        Get
            Return _sourceStream.Length
        End Get
    End Property

    Public Overrides Property Position As Long
        Get
            Return _sourceStream.Position
        End Get
        Set(ByVal value As Long)
            _sourceStream.Position = value
        End Set
    End Property

    Public Overrides Function Read(buffer() As Byte, offset As Integer, count As Integer) As Integer
        Dim totalBytesRead As Integer = 0

        While totalBytesRead < count
            Dim bytesRead As Integer = _sourceStream.Read(buffer, offset + totalBytesRead, count - totalBytesRead)

            If bytesRead = 0 Then

                If _enableLooping Then
                    _sourceStream.Position = 0
                Else
                    If Not _sourceStream.Position = 0 Then
                        Exit While
                    End If
                End If
            End If
            totalBytesRead += bytesRead
        End While
            
        Return totalBytesRead
    End Function
End Class
Public Class MusicManager

    Private Const NO_MUSIC As String = "*nomusic*" ' contains * as character, which cannot be in a filename
    Private Const DEFAULT_FADE_SPEED As Single = 0.02F

    Private Shared _songs As Dictionary(Of String, SongContainer) = New Dictionary(Of String, SongContainer)()
    Public Shared Property Volume As Single = 1.0F
    Private Shared _lastVolume As Single = 1.0F
    Private Shared _muted As Boolean = False
    Private Shared _paused As Boolean = False
    Public Shared _isLooping As Boolean = False

    ' currently playing song
    Private Shared _currentSongName As String = NO_MUSIC
    ' if the song in _currentSong is an actual existing song
    Private Shared _currentSongExists As Boolean = False
    Private Shared _currentSong As SongContainer = Nothing

    ' time until music playback is paused for sound effect
    Private Shared _pausedUntil As Date
    Private Shared _isPausedForSound As Boolean = False

    ' time until the intro of a song plays
    Private Shared _introMuteTime As Date
    Public Shared _introEndTime As Date
    Private Shared _isIntroStarted As Boolean = False
    ' song that gets played after the intro finished
    Private Shared _introContinueSong As String

    ' song that plays after fading is finished
    Private Shared _nextSong As String
    ' speeds that get added/subtracted from the volume to fade the song
    Private Shared _fadeSpeed As Single = DEFAULT_FADE_SPEED
    ' if the song that gets played after fading completed is an intro to another song
    Private Shared _fadeIntoIntro As Boolean = False
    Private Shared _isFadingOut As Boolean = False
    Private Shared _isFadingIn As Boolean = False
    ' NAudio properties
    Public Shared outputDevice As WaveOutEvent
	Public Shared audioFile As VorbisWaveReader
	Public Shared _stream As WaveChannel32

	Public Shared Property MasterVolume As Single = 1.0F
	Public Shared ReadOnly Property CurrentSong As SongContainer
		Get
			Return _currentSong
		End Get
	End Property

	Public Shared Property Muted As Boolean
		Get
			Return _muted
		End Get
		Set(value As Boolean)
			If _muted <> value Then
				_muted = value

				If _muted = True Then
					If outputDevice IsNot Nothing Then
						Volume = 0.0F
						Core.GameMessage.ShowMessage(Localization.GetString("game_message_audio_off"), 12, FontManager.MainFont, Color.White)
					End If

				Else
					If outputDevice IsNot Nothing Then
						If _isPausedForSound = True Then
							_muted = True
							Volume = 0.0F
						Else
							Volume = 1.0F
							Core.GameMessage.ShowMessage(Localization.GetString("game_message_audio_on"), 12, FontManager.MainFont, Color.White)
						End If
					End If
				End If
			End If
		End Set
	End Property
	Public Shared Property Paused As Boolean
		Get
			Return _paused
		End Get
		Set(value As Boolean)
			If _paused <> value Then
				_paused = value

				If _paused = True Then
					If outputDevice IsNot Nothing Then
						outputDevice.Pause()
						_introMuteTime = Date.Now
					End If
				Else
					ResumePlayback()
				End If
			End If
		End Set
	End Property
	Public Shared Sub Setup()
		MasterVolume = 1.0F
		If Muted = True Then
			Volume = 0.0F
		Else
			Volume = 1.0F
		End If
		_nextSong = ""
		_fadeSpeed = DEFAULT_FADE_SPEED
		_isFadingOut = False
		_isFadingIn = False
		_isLooping = True
	End Sub

	Public Shared Sub Clear()
		_songs.Clear()
		LoadMusic(False)
	End Sub

	Public Shared Sub ClearCurrentlyPlaying()
		' cleans all remains of currently playing songs
		_currentSongExists = False
		_currentSong = Nothing
		_currentSongName = NO_MUSIC
		_isIntroStarted = False
	End Sub

	Public Shared Sub PlayNoMusic()
		' fades out current track and sets to NO_MUSIC
		Play(NO_MUSIC)
	End Sub

	Public Shared Sub Update()
		If _isPausedForSound Then
			If Date.Now >= _pausedUntil Then
				If MusicManager.Paused = True Then
					_isPausedForSound = False
					Paused = False
				End If
			End If
		Else

			' fading
			If _isFadingOut Then
				Volume -= _fadeSpeed

				If Volume <= 0F Then

					Volume = 0F
					_isFadingOut = False
					_isFadingIn = True

					Dim song = GetSong(_nextSong)

					If Not song Is Nothing Then

						Play(song)
						_nextSong = ""

						If _fadeIntoIntro Then
							_fadeIntoIntro = False
							_introEndTime = Date.Now + song.Duration
							_isIntroStarted = True
						Else
							_isLooping = True
						End If

					Else

						' no song found, do not fade into anything
						_fadeIntoIntro = False
						ClearCurrentlyPlaying()
						_isFadingIn = False
						If Muted = True Then
							Volume = 0.0F
						Else
							Volume = 1.0F
						End If
						If _nextSong = NO_MUSIC Then
							_nextSong = ""
							MusicManager.Stop()
						End If

					End If

				End If

			ElseIf _isFadingIn Then
				If Muted = True Then
					Volume = 0.0F
					_isFadingIn = False
				Else
					Volume += _fadeSpeed
					If Volume >= 1.0F Then
						Volume = 1.0F
						_isFadingIn = False
					End If
				End If
			End If

			' intro
			If _isIntroStarted Then
				If Paused = False Then
					If Date.Now >= _introEndTime Then
						Dim song = GetSong(_introContinueSong)
						_isLooping = True
						_isIntroStarted = False
						Play(song)
					End If
				End If
			End If
		End If

		If Core.GameInstance.IsActive AndAlso _lastVolume <> (Volume * MasterVolume) Then
			UpdateVolume()
		End If
	End Sub

	Public Shared Sub UpdateVolume()
		_lastVolume = Volume * MasterVolume
		If Not _stream Is Nothing Then
			_stream.Volume = Volume * MasterVolume
		End If
	End Sub

	Public Shared Sub PauseForSound(ByVal sound As SoundEffect)
		_isPausedForSound = True
		_pausedUntil = Date.Now + sound.Duration
		MusicManager.Pause()
	End Sub

	Public Shared Sub Pause()
		MusicManager.Paused = True
	End Sub

	Public Shared Sub [Stop]()
		If Not outputDevice Is Nothing Then
			outputDevice.Stop()
			outputDevice.Dispose()
		End If
		_isIntroStarted = False
	End Sub

	Public Shared Sub ResumePlayback()
		If Not _currentSong Is Nothing Then

			If outputDevice IsNot Nothing Then
				' if an intro was playing while the music player was paused, calculate its end time
				If outputDevice.PlaybackState = PlaybackState.Paused AndAlso _isIntroStarted Then
					Dim pauseTime As TimeSpan = Date.Now.Subtract(_introMuteTime)
					_introEndTime = _introEndTime + pauseTime

				End If
				outputDevice.Play()
			End If
		End If

	End Sub

	Private Shared Sub Play(song As SongContainer)
		If Not song Is Nothing Then
			Logger.Debug($"Play song [{song.Name}]")
			If Not outputDevice Is Nothing Then
				outputDevice.Dispose()
			End If
			outputDevice = New WaveOutEvent()
			audioFile = New VorbisWaveReader(song.Song)
			_stream = New NAudio.Wave.WaveChannel32(New LoopStream(audioFile, _isLooping))
			outputDevice.Init(_stream)
			If Paused = False Then
				outputDevice.Play()
			End If
			_stream.Volume = Volume * MasterVolume
			_currentSongExists = True
			_currentSongName = song.Name
			_currentSong = song
		Else
			_currentSongExists = False
			_currentSongName = NO_MUSIC
			_currentSong = Nothing
		End If

	End Sub

	Private Shared Sub FadeInto(song As SongContainer, fadeSpeed As Single)
        _isFadingOut = True
        If Not song Is Nothing Then
            _nextSong = song.Name
        Else
            _nextSong = NO_MUSIC
        End If
        _fadeSpeed = fadeSpeed
    End Sub

    Public Shared Function Play(song As String) As SongContainer
        Return Play(song, False, DEFAULT_FADE_SPEED)
    End Function

    Public Shared Function Play(song As String, playIntro As Boolean, Optional loopSong As Boolean = True) As SongContainer
        Return Play(song, playIntro, DEFAULT_FADE_SPEED)
    End Function

    Public Shared Function Play(song As String, playIntro As Boolean, fadeSpeed As Single, Optional loopSong As Boolean = True) As SongContainer

        Dim playedSong As SongContainer = Nothing

        ' get the current song, only play if it's different
        Dim currentSong = GetCurrentSong().ToLowerInvariant()
        Dim songName = GetSongName(song)

        If currentSong = NO_MUSIC OrElse currentSong <> songName Then

            If playIntro = True Then
                _isLooping = False
                Dim introSong = GetSong("intro\" + songName)
                If Not introSong Is Nothing Then
                    If introSong.Origin = GetSong(songName).Origin Then

                        ' play the intro
                        ' setup the continue song
                        _introContinueSong = songName
                        ' do not repeat media player, do not want intro to loop
                        '_isLooping = False

                        If fadeSpeed > 0F Then
                            _isIntroStarted = False
                            _fadeIntoIntro = True
                            FadeInto(introSong, fadeSpeed)
                        Else
                            _isIntroStarted = True
                            _introEndTime = Date.Now + introSong.Duration
                            Play(introSong)
                        End If

                        playedSong = introSong

                        ' load the next song so the end of the intro doesn't lag
                        GetSong(song)
                    End If
                Else
                    _isIntroStarted = False
                    _fadeIntoIntro = False
                End If
            Else
                _isIntroStarted = False
                _fadeIntoIntro = False
            End If

            ' intro was not requested or does not exist
            If Not _isIntroStarted AndAlso Not _fadeIntoIntro Then
                If loopSong = True Then
                    _isLooping = True
                Else
                    _isLooping = False
                End If
                Dim nextSong = GetSong(song)
                If fadeSpeed > 0F Then
                    FadeInto(nextSong, fadeSpeed)
                Else
                    Play(nextSong)
                End If

                playedSong = nextSong

                End If

            End If

        Return playedSong

    End Function

    Public Shared Function SongExists(songName As String) As Boolean
        Return Not GetSong(songName) Is Nothing
    End Function

    Private Shared Function GetCurrentSong() As String
        ' if the currently playing song is an intro, return the song that plays after the intro
        ' this prevents the same song from replaying if it starts playing while the intro is still in effect

        ' but if it's already fading, do not play the song if the song we are fading into is the same.
        ' also if we are fading into an intro, get the song that the intro would continue to
        If _isFadingOut Then
            If _fadeIntoIntro Then
                Return _introContinueSong
            Else
                Return _nextSong
            End If
        Else
            If _isIntroStarted Then
                Return _introContinueSong
            Else
                Return _currentSongName
            End If
        End If
    End Function

    Private Shared Function GetSong(songName As String) As SongContainer
        Dim key = GetSongName(songName)

        If _songs.ContainsKey(key) = True Then
            Return _songs(key)
        Else
            Dim defaultSongFilePath = GameController.GamePath & "\Content\" & "Songs\" & key & ".ogg"
            Dim songFilePath = GameController.GamePath & GameModeManager.ActiveGameMode.ContentPath & "Songs\" & key & ".ogg"
            If File.Exists(songFilePath) Then
                If AddSong(key, False) = True Then
                    Return _songs(key)
                End If
            ElseIf File.Exists(defaultSongFilePath) Then
                If AddSong(key, False) = True Then
                    Return _songs(key)
                End If
            Else
                Logger.Log(Logger.LogTypes.Warning, "MusicManager.vb: Cannot find music file """ & songName & """. Return nothing.")
            End If
            Return Nothing
        End If

    End Function


    Private Shared Function GetSongName(song As String) As String
        Dim key = song.ToLowerInvariant()
        Dim aliasMap = SongAliasMap
        If aliasMap.ContainsKey(key) Then
            key = aliasMap(key).ToLowerInvariant()
        End If
        Return key
    End Function

    Private Shared Function AddSong(ByVal Name As String, ByVal forceReplace As Boolean) As Boolean
        Try
            Dim cContent As ContentManager = ContentPackManager.GetContentManager("Songs\" & Name, ".ogg")

            Dim loadSong As Boolean = False
            Dim removeSong As Boolean = False

            If _songs.ContainsKey(GetSongName(Name)) = False Then
                loadSong = True
            ElseIf forceReplace = True And _songs(GetSongName(Name)).IsStandardSong = True Then
                removeSong = True
                loadSong = True
            End If

            If loadSong = True Then
                Dim songFilePath As String = Nothing

                If System.IO.File.Exists(GameController.GamePath & "\" & cContent.RootDirectory & "\Songs\" & Name & ".ogg") = True Then
                    songFilePath = GameController.GamePath & "\" & cContent.RootDirectory & "\Songs\" & Name & ".ogg"
                Else
                    Logger.Log(Logger.LogTypes.Warning, "MusicManager.vb: Song at """ & GameController.GamePath & "\" & cContent.RootDirectory & "\Songs\" & Name & """ was not found!")
                    Return False
                End If

                If Not songFilePath Is Nothing Then
                    If removeSong = True Then
                        _songs.Remove(GetSongName(Name))
                    End If
                    Dim Duration = GetSongDuration(songFilePath)
                    _songs.Add(GetSongName(Name), New SongContainer(songFilePath, Name, Duration, cContent.RootDirectory))
                End If
            End If
        Catch ex As Exception
            Logger.Log(Logger.LogTypes.Warning, "MusicManager.vb: File at ""Songs\" & Name & """ is not a valid song file!")
            Return False
        End Try
        Return True
    End Function

    Public Shared Sub LoadMusic(ByVal forceReplace As Boolean)
        For Each musicFile As String In System.IO.Directory.GetFiles(GameController.GamePath & GameModeManager.ActiveGameMode.ContentPath & "Songs\", "*.*", IO.SearchOption.AllDirectories)
            If musicFile.EndsWith(".ogg") = True Then
                Dim isIntro As Boolean = False
                If musicFile.Contains("\Songs\intro\") = True Then
                    isIntro = True
                End If

                If isIntro = False Then
                    musicFile = System.IO.Path.GetFileNameWithoutExtension(musicFile)
                Else
                    musicFile = "intro\" & System.IO.Path.GetFileNameWithoutExtension(musicFile)
                End If

                AddSong(musicFile, forceReplace)
            End If
        Next
        If Core.GameOptions.ContentPackNames.Count > 0 Then
            For Each c As String In Core.GameOptions.ContentPackNames
                Dim path As String = GameController.GamePath & "\ContentPacks\" & c & "\Songs\"
                If System.IO.Directory.Exists(path) = True Then
                    For Each musicFile As String In System.IO.Directory.GetFiles(path, "*.*", IO.SearchOption.AllDirectories)
                        If musicFile.EndsWith(".ogg") = True Then
                            Dim isIntro As Boolean = False
                            If musicFile.Contains("\Songs\intro\") = True Then
                                isIntro = True
                            End If

                            If isIntro = False Then
                                musicFile = System.IO.Path.GetFileNameWithoutExtension(musicFile)
                            Else
                                musicFile = "intro\" & System.IO.Path.GetFileNameWithoutExtension(musicFile)
                            End If
                            AddSong(musicFile, forceReplace)
                        End If
                    Next
                End If
            Next
        End If
    End Sub

    Private Shared Function GetSongDuration(songFilePath As String) As TimeSpan

        Dim DurationFile As VorbisWaveReader = New VorbisWaveReader(songFilePath)
        Dim SongDuration = DurationFile.TotalTime
        DurationFile.Dispose()
        Return SongDuration

    End Function

    Private Shared ReadOnly Property SongAliasMap As Dictionary(Of String, String)
        Get
            Return New Dictionary(Of String, String)() From
            {
                {"welcome", "RouteMusic1"},
                {"battle", "johto_wild"},
                {"batleintro", "battle_intro"},
                {"johto_battle_intro", "battle_intro"},
                {"darkcave", "dark_cave"},
                {"showmearound", "show_me_around"},
                {"sprouttower", "sprout_tower"},
                {"johto_rival_intro", "johto_rivalintro"},
                {"johto_rival_appear", "johto_rival_encounter"},
                {"ilex_forest", "IlexForest"},
                {"union_cave", "IlexForest"},
                {"mt_mortar", "IlexForest"},
                {"whirlpool_islands", "IlexForest"},
                {"tohjo_falls", "IlexForest"}
            }
        End Get
    End Property

End Class