diff --git a/composeApp/src/androidMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt b/composeApp/src/androidMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
deleted file mode 100644
index f38d731..0000000
--- a/composeApp/src/androidMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
+++ /dev/null
@@ -1,62 +0,0 @@
-package mg.dot.feufaro.midi
-
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
-import mg.dot.feufaro.FileRepository
-
-actual class MidiWriterKotlin actual constructor(private val fileRepository: FileRepository) {
-    private val sequence = MidiSequence(60)
-    private val track    = sequence.createTrack()
-    private var tick: Long = 0
-    private var nextTick: MutableList<MidiPitch> = mutableListOf()
-    private val lastPitch : MutableList<Int> = mutableListOf()
-    private val useChord : Boolean = true
-    actual fun addNote( voiceNumber: Int, note: Int, velocity: Int, tick: Long) {
-        val channel = (voiceNumber -1).coerceIn(0, 3)
-        var finalNote = note
-
-        if (voiceNumber == 3 || voiceNumber == 4) {
-            finalNote -= 12
-        }
-        if (lastPitch.size > voiceNumber && lastPitch[voiceNumber] > 0) {
-            sequence.addSequence(channel, lastPitch[voiceNumber], tick)
-        }
-        var finalVelocity = velocity
-        var midiNote = finalNote
-        if (finalNote <= 0) {
-            midiNote = 40
-            finalVelocity = 0
-        }
-        sequence.addSequence(channel, midiNote, tick, 90, finalVelocity)
-
-        while(lastPitch.size <= voiceNumber) {
-            lastPitch.add(0)
-        }
-        lastPitch[voiceNumber] = midiNote
-    }
-    actual fun save(filePath: String) {
-        val parseScope = CoroutineScope(Dispatchers.Default)
-        parseScope.launch {
-            sequence.write()
-            fileRepository.saveFile(filePath, sequence.out.toByteArray())
-            //val fout = fileRepository.getOutputStream(filePath)
-        }
-    }
-    actual fun addMetaMessage(type: Int, tick: Int, nbData: Int, metaByteString: String) {
-        sequence.addMeta( type, tick, nbData, metaByteString)
-    }
-    actual fun process(pitches: List<MidiPitch>) {
-        val lastTick = 0
-        nextTick.clear()
-        // addMetaMessage(0x59, 4, 2, 2,0)
-        tick = 0
-        pitches.forEach {
-            if (it.metaType > 0) {
-                addMetaMessage(it.metaType, it.tick, it.metaByteSize, it.metaBytes)
-            } else if (it.pitch != "") {
-                addNote(it.voiceNumber, it.pitch.toInt(), 100, it.tick.toLong())
-            }
-        }
-    }
-}
\ No newline at end of file
diff --git a/composeApp/src/commonMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt b/composeApp/src/commonMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
index cc32aad..e62d02b 100644
--- a/composeApp/src/commonMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
+++ b/composeApp/src/commonMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
@@ -1,10 +1,62 @@
 package mg.dot.feufaro.midi
 
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.launch
 import mg.dot.feufaro.FileRepository
 
-expect class MidiWriterKotlin(fileRepository: FileRepository) {
-    fun addNote( voiceNumber: Int, note: Int, velocity: Int, tick: Long)
-    fun save(filePath: String)
-    fun addMetaMessage(type: Int, tick: Int, nbData: Int, metaByteString: String)
-    fun process(pitches: List<MidiPitch>)
+class MidiWriterKotlin  constructor(private val fileRepository: FileRepository) {
+    private val sequence = MidiSequence(60)
+    private val track    = sequence.createTrack()
+    private var tick: Long = 0
+    private var nextTick: MutableList<MidiPitch> = mutableListOf()
+    private val lastPitch : MutableList<Int> = mutableListOf()
+    private val useChord : Boolean = true
+    fun addNote( voiceNumber: Int, note: Int, velocity: Int, tick: Long) {
+        val channel = (voiceNumber -1).coerceIn(0, 3)
+        var finalNote = note
+
+        if (voiceNumber == 3 || voiceNumber == 4) {
+            finalNote -= 12
+        }
+        if (lastPitch.size > voiceNumber && lastPitch[voiceNumber] > 0) {
+            sequence.addSequence(channel, lastPitch[voiceNumber], tick)
+        }
+        var finalVelocity = velocity
+        var midiNote = finalNote
+        if (finalNote <= 0) {
+            midiNote = 40
+            finalVelocity = 0
+        }
+        sequence.addSequence(channel, midiNote, tick, 90, finalVelocity)
+
+        while(lastPitch.size <= voiceNumber) {
+            lastPitch.add(0)
+        }
+        lastPitch[voiceNumber] = midiNote
+    }
+    fun save(filePath: String) {
+        val parseScope = CoroutineScope(Dispatchers.Default)
+        parseScope.launch {
+            sequence.write()
+            fileRepository.saveFile(filePath, sequence.out.toByteArray())
+            //val fout = fileRepository.getOutputStream(filePath)
+        }
+    }
+    fun addMetaMessage(type: Int, tick: Int, nbData: Int, metaByteString: String) {
+        sequence.addMeta( type, tick, nbData, metaByteString)
+    }
+    fun process(pitches: List<MidiPitch>) {
+        val lastTick = 0
+        nextTick.clear()
+        // addMetaMessage(0x59, 4, 2, 2,0)
+        tick = 0
+        pitches.forEach {
+            if (it.metaType > 0) {
+                addMetaMessage(it.metaType, it.tick, it.metaByteSize, it.metaBytes)
+            } else if (it.pitch != "") {
+                addNote(it.voiceNumber, it.pitch.toInt(), 100, it.tick.toLong())
+            }
+        }
+    }
 }
\ No newline at end of file
diff --git a/composeApp/src/desktopMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt b/composeApp/src/desktopMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
deleted file mode 100644
index 21e39a7..0000000
--- a/composeApp/src/desktopMain/kotlin/mg/dot/feufaro/midi/MidiWriterKotlin.kt
+++ /dev/null
@@ -1,73 +0,0 @@
-package mg.dot.feufaro.midi
-
-import kotlinx.coroutines.CoroutineScope
-import kotlinx.coroutines.Dispatchers
-import kotlinx.coroutines.launch
-import mg.dot.feufaro.FileRepository
-import javax.sound.midi.*
-
-actual class MidiWriterKotlin actual constructor(private val fileRepository: FileRepository) {
-    private val sequence = Sequence(Sequence.PPQ, 60)
-    private val track    = sequence.createTrack()
-    private var tick: Long = 0
-    private var nextTick: MutableList<MidiPitch> = mutableListOf()
-    private val noteOn   = ShortMessage()
-    private val noteOff = ShortMessage()
-    private val lastPitch : MutableList<Int> = mutableListOf()
-    private val useChord : Boolean = true
-    actual fun addNote( voiceNumber: Int, note: Int, velocity: Int, tick: Long) {
-        val channel = (voiceNumber -1).coerceIn(0, 3)
-        var finalNote = note
-
-        if (voiceNumber == 3 || voiceNumber == 4) {
-            finalNote -= 12
-        }
-        if (lastPitch.size > voiceNumber && lastPitch[voiceNumber] > 0) {
-            val offMsg = ShortMessage()
-            offMsg.setMessage(ShortMessage.NOTE_OFF, channel, lastPitch[voiceNumber], 0)
-            track.add(MidiEvent(offMsg, tick))
-        }
-        var finalVelocity = velocity
-        var midiNote = finalNote
-        if (finalNote <= 0) {
-            midiNote = 40
-            finalVelocity = 0
-        }
-        val onMsg = ShortMessage()
-        onMsg.setMessage(ShortMessage.NOTE_ON, channel, midiNote, finalVelocity)
-        track.add(MidiEvent(onMsg, tick))
-
-        while(lastPitch.size <= voiceNumber) {
-            lastPitch.add(0)
-        }
-        lastPitch[voiceNumber] = midiNote
-    }
-    actual fun save(filePath: String) {
-        val parseScope = CoroutineScope(Dispatchers.Default)
-        parseScope.launch {
-            val midiFileName = fileRepository.getFileName(filePath)
-            val out = fileRepository.getOutputStream(midiFileName)
-            println("write to : $midiFileName   ")
-            MidiSystem.write(sequence, 1, out)
-            out.close()
-        }
-    }
-    actual fun addMetaMessage(type: Int, tick: Int, nbData: Int, metaByteString: String) {
-        val byteArray = metaByteString.toByteArray()
-        val metaMessage = MetaMessage(type, byteArray, nbData)
-        track.add(MidiEvent(metaMessage, tick.toLong()))
-    }
-    actual fun process(pitches: List<MidiPitch>) {
-        val lastTick = 0
-        nextTick.clear()
-        // addMetaMessage(0x59, 4, 2, 2,0)
-        tick = 0
-        pitches.forEach {
-            if (it.metaType > 0) {
-                addMetaMessage(it.metaType, it.tick, it.metaByteSize, it.metaBytes)
-            } else if (it.pitch != "") {
-                addNote(it.voiceNumber, it.pitch.toInt(), 100, it.tick.toLong())
-            }
-        }
-    }
-}
\ No newline at end of file