feat: gli spartiti importati restano tra gli esercizi, eliminabili

- ImportedExerciseRepository: persistenza JSON degli import (titolo dal
  nome file, note con durate/bemolli, metro; max 50, più recenti primi)
- FilePicker passa anche il nome del file (expect + 3 actual)
- PracticeSetupScreen salva la sequenza importata prima di avviare
- ExercisesScreen: sezione 'Importati' con anteprima e cestino
- fix: picker desktop su Dispatchers.Swing con finestra parent (l'import
  XML congelava l'app: dialogo Swing su thread di background)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

shared/src/androidMain/kotlin/com/notemusicali/ui/components/FilePicker.android.kt

@@ -10,7 +10,7 @@ import com.notemusicali.scores.extractMusicXmlFromBytes
 @Composable
 actual fun rememberFilePickerLauncher(
     mimeTypes: List<String>,
-    onFileContent: (String) -> Unit,
+    onFileContent: (fileName: String, content: String) -> Unit,
 ): () -> Unit {
     val context = LocalContext.current
     val launcher = rememberLauncherForActivityResult(
@@ -22,7 +22,7 @@ actual fun rememberFilePickerLauncher(
                     val bytes = stream.readBytes()
                     val content = extractMusicXmlFromBytes(bytes)
                     if (content != null) {
-                        onFileContent(content)
+                        onFileContent(displayNameOf(context, it), content)
                     }
                 }
             } catch (_: Exception) {
@@ -33,3 +33,14 @@ actual fun rememberFilePickerLauncher(
 
     return { launcher.launch(mimeTypes.toTypedArray()) }
 }
+
+private fun displayNameOf(context: android.content.Context, uri: Uri): String {
+    return try {
+        context.contentResolver.query(uri, null, null, null, null)?.use { cursor ->
+            val idx = cursor.getColumnIndex(android.provider.OpenableColumns.DISPLAY_NAME)
+            if (idx >= 0 && cursor.moveToFirst()) cursor.getString(idx) else null
+        } ?: (uri.lastPathSegment ?: "Import")
+    } catch (_: Exception) {
+        uri.lastPathSegment ?: "Import"
+    }
+}

shared/src/commonMain/composeResources/values-en/strings.xml

@@ -234,4 +234,6 @@
     <string name="info_website">djluza.com</string>
     <string name="info_privacy_policy">Privacy Policy</string>
     <string name="info_privacy_url">https://djluza.com/intono/privacy</string>
+    <string name="imported_exercises">Imported</string>
+    <string name="delete_imported">Delete imported score</string>
 </resources>

shared/src/commonMain/composeResources/values/strings.xml

@@ -234,4 +234,6 @@
     <string name="info_website">djluza.com</string>
     <string name="info_privacy_policy">Privacy Policy</string>
     <string name="info_privacy_url">https://djluza.com/intono/privacy</string>
+    <string name="imported_exercises">Importati</string>
+    <string name="delete_imported">Elimina spartito importato</string>
 </resources>

shared/src/commonMain/kotlin/com/notemusicali/exercises/ImportedExercises.kt

@@ -0,0 +1,80 @@
+package com.notemusicali.exercises
+
+import com.notemusicali.music.MusicalNote
+import com.notemusicali.music.NoteDuration
+import com.notemusicali.music.NoteSequence
+import com.notemusicali.util.currentTimeMillis
+import com.russhwolf.settings.Settings
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.encodeToString
+import kotlinx.serialization.json.Json
+
+@Serializable
+data class StoredNote(
+    val midi: Int,
+    val duration: NoteDuration = NoteDuration.QUARTER,
+    val flat: Boolean = false,
+)
+
+@Serializable
+data class ImportedExercise(
+    val id: String,
+    val title: String,
+    val notes: List<StoredNote>,
+    val beats: Int = 4,
+    val beatType: Int = 4,
+) {
+    fun toNoteSequence(): NoteSequence = NoteSequence(
+        name = title,
+        notes = notes.map { MusicalNote.fromMidi(it.midi, it.duration, preferFlat = it.flat) },
+        beats = beats,
+        beatType = beatType,
+    )
+}
+
+/** Persistenza degli spartiti importati dall'utente (JSON su multiplatform-settings). */
+internal class ImportedExerciseStore(private val settings: Settings) {
+
+    private val json = Json { ignoreUnknownKeys = true }
+
+    fun getAll(): List<ImportedExercise> {
+        val raw = settings.getStringOrNull(KEY) ?: return emptyList()
+        return try {
+            json.decodeFromString<List<ImportedExercise>>(raw)
+        } catch (_: Exception) {
+            emptyList()
+        }
+    }
+
+    fun add(title: String, sequence: NoteSequence, nowMs: Long = currentTimeMillis()): ImportedExercise {
+        val exercise = ImportedExercise(
+            id = nowMs.toString(),
+            title = title,
+            notes = sequence.notes.map { StoredNote(it.midiNumber, it.duration, it.preferFlat) },
+            beats = sequence.beats,
+            beatType = sequence.beatType,
+        )
+        val updated = (listOf(exercise) + getAll()).take(MAX_IMPORTED)
+        settings.putString(KEY, json.encodeToString(updated))
+        return exercise
+    }
+
+    fun remove(id: String) {
+        val remaining = getAll().filterNot { it.id == id }
+        settings.putString(KEY, json.encodeToString(remaining))
+    }
+
+    private companion object {
+        const val KEY = "imported_exercises"
+        const val MAX_IMPORTED = 50
+    }
+}
+
+/** Facade con lo storage reale dell'app. */
+object ImportedExerciseRepository {
+    private val store by lazy { ImportedExerciseStore(Settings()) }
+
+    fun getAll(): List<ImportedExercise> = store.getAll()
+    fun add(title: String, sequence: NoteSequence): ImportedExercise = store.add(title, sequence)
+    fun remove(id: String) = store.remove(id)
+}

shared/src/commonMain/kotlin/com/notemusicali/ui/components/FilePicker.kt

@@ -5,10 +5,10 @@ import androidx.compose.runtime.Composable
 /**
  * Platform-specific file picker launcher.
  * Returns a lambda that, when invoked, opens the file picker.
- * [onFileContent] is called with the file content as a String.
+ * [onFileContent] is called with the display name of the file and its content.
  */
 @Composable
 expect fun rememberFilePickerLauncher(
     mimeTypes: List<String>,
-    onFileContent: (String) -> Unit,
+    onFileContent: (fileName: String, content: String) -> Unit,
 ): () -> Unit

shared/src/commonMain/kotlin/com/notemusicali/ui/exercises/ExercisesScreen.kt

@@ -27,8 +27,16 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import androidx.compose.material.icons.outlined.Delete
+import androidx.compose.material3.IconButton
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import com.notemusicali.exercises.Exercise
 import com.notemusicali.exercises.ExerciseRepository
+import com.notemusicali.exercises.ImportedExercise
+import com.notemusicali.exercises.ImportedExerciseRepository
 import notemusicali.shared.generated.resources.Res
 import notemusicali.shared.generated.resources.*
 import org.jetbrains.compose.resources.stringResource
@@ -46,6 +54,8 @@ fun ExercisesScreen(
     onBack: () -> Unit,
     onExerciseSelected: (NoteSequence) -> Unit,
 ) {
+    var imported by remember { mutableStateOf(ImportedExerciseRepository.getAll()) }
+
     Box(
         modifier = Modifier.fillMaxSize(),
         contentAlignment = Alignment.TopCenter,
@@ -70,6 +80,28 @@ fun ExercisesScreen(
                     onClick = { onExerciseSelected(exercise.sequence) },
                 )
             }
+
+            if (imported.isNotEmpty()) {
+                item {
+                    Text(
+                        text = stringResource(Res.string.imported_exercises),
+                        fontSize = 14.sp,
+                        fontWeight = FontWeight.SemiBold,
+                        color = Color.White.copy(alpha = 0.5f),
+                        modifier = Modifier.padding(top = 8.dp),
+                    )
+                }
+                items(imported, key = { it.id }) { entry ->
+                    ImportedExerciseCard(
+                        entry = entry,
+                        onClick = { onExerciseSelected(entry.toNoteSequence()) },
+                        onDelete = {
+                            ImportedExerciseRepository.remove(entry.id)
+                            imported = ImportedExerciseRepository.getAll()
+                        },
+                    )
+                }
+            }
         }
     }
     }
@@ -133,3 +165,49 @@ private fun StarRating(level: Int) {
         }
     }
 }
+
+@Composable
+private fun ImportedExerciseCard(
+    entry: ImportedExercise,
+    onClick: () -> Unit,
+    onDelete: () -> Unit,
+) {
+    GradientCard(
+        gradient = CardGradients.scoreFile,
+        onClick = onClick,
+        modifier = Modifier.fillMaxWidth(),
+    ) {
+        Row(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.SpaceBetween,
+            verticalAlignment = Alignment.CenterVertically,
+        ) {
+            Text(
+                text = entry.title,
+                fontSize = 20.sp,
+                fontWeight = FontWeight.SemiBold,
+                color = Color.White,
+                modifier = Modifier.weight(1f),
+            )
+            IconButton(onClick = onDelete) {
+                Icon(
+                    imageVector = Icons.Outlined.Delete,
+                    contentDescription = stringResource(Res.string.delete_imported),
+                    tint = Color.White.copy(alpha = 0.6f),
+                )
+            }
+        }
+        Spacer(modifier = Modifier.height(4.dp))
+        StaffPreview(
+            notes = entry.toNoteSequence().notes,
+            beats = entry.beats,
+            beatType = entry.beatType,
+        )
+        Spacer(modifier = Modifier.height(4.dp))
+        Text(
+            text = stringResource(Res.string.n_notes, entry.notes.size),
+            fontSize = 12.sp,
+            color = Color.White.copy(alpha = 0.5f),
+        )
+    }
+}

shared/src/commonMain/kotlin/com/notemusicali/ui/practice/PracticeSetupScreen.kt

@@ -28,6 +28,7 @@ import androidx.compose.ui.graphics.vector.ImageVector
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import com.notemusicali.exercises.ImportedExerciseRepository
 import com.notemusicali.music.MusicXmlParser
 import com.notemusicali.music.NoteSequence
 import com.notemusicali.ui.components.BackTopBar
@@ -47,10 +48,17 @@ fun PracticeSetupScreen(
 ) {
     val filePickerLauncher = rememberFilePickerLauncher(
         mimeTypes = listOf("text/xml", "application/xml", "*/*"),
-        onFileContent = { content ->
+        onFileContent = { fileName, content ->
             try {
-                val sequence = MusicXmlParser.parse(content, "MusicXML Import")
+                val title = fileName
+                    .removeSuffix(".musicxml").removeSuffix(".music.xml")
+                    .removeSuffix(".xml").removeSuffix(".mxl")
+                    .replace('_', ' ')
+                    .ifBlank { "MusicXML Import" }
+                val sequence = MusicXmlParser.parse(content, title)
                 if (sequence.notes.isNotEmpty()) {
+                    // Lo spartito importato resta disponibile tra gli esercizi
+                    ImportedExerciseRepository.add(title, sequence)
                     onMusicXmlLoaded(sequence)
                 }
             } catch (_: Exception) {

shared/src/commonTest/kotlin/com/notemusicali/exercises/ImportedExerciseStoreTest.kt

@@ -0,0 +1,61 @@
+package com.notemusicali.exercises
+
+import com.notemusicali.music.MusicalNote
+import com.notemusicali.music.NoteDuration
+import com.notemusicali.music.NoteSequence
+import com.russhwolf.settings.MapSettings
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class ImportedExerciseStoreTest {
+
+    private fun sequence() = NoteSequence(
+        name = "Test",
+        notes = listOf(
+            MusicalNote.fromMidi(60, NoteDuration.EIGHTH),
+            MusicalNote.fromMidi(70, NoteDuration.HALF, preferFlat = true),
+        ),
+        beats = 3,
+        beatType = 4,
+    )
+
+    @Test
+    fun `added exercise round trips with notes durations flats and meter`() {
+        val store = ImportedExerciseStore(MapSettings())
+        store.add("Il mio spartito", sequence(), nowMs = 1000L)
+
+        val loaded = store.getAll().single()
+        assertEquals("Il mio spartito", loaded.title)
+        val seq = loaded.toNoteSequence()
+        assertEquals(2, seq.notes.size)
+        assertEquals(60, seq.notes[0].midiNumber)
+        assertEquals(NoteDuration.EIGHTH, seq.notes[0].duration)
+        assertEquals("SIb", seq.notes[1].displayName)
+        assertEquals(NoteDuration.HALF, seq.notes[1].duration)
+        assertEquals(3, seq.beats)
+        assertEquals(4, seq.beatType)
+    }
+
+    @Test
+    fun `newest import comes first`() {
+        val store = ImportedExerciseStore(MapSettings())
+        store.add("Primo", sequence(), nowMs = 1L)
+        store.add("Secondo", sequence(), nowMs = 2L)
+        assertEquals(listOf("Secondo", "Primo"), store.getAll().map { it.title })
+    }
+
+    @Test
+    fun `remove deletes only the requested exercise`() {
+        val store = ImportedExerciseStore(MapSettings())
+        val a = store.add("A", sequence(), nowMs = 1L)
+        store.add("B", sequence(), nowMs = 2L)
+        store.remove(a.id)
+        assertEquals(listOf("B"), store.getAll().map { it.title })
+    }
+
+    @Test
+    fun `empty storage yields empty list`() {
+        assertTrue(ImportedExerciseStore(MapSettings()).getAll().isEmpty())
+    }
+}

shared/src/desktopMain/kotlin/com/notemusicali/ui/components/FilePicker.desktop.kt

@@ -5,31 +5,41 @@ import androidx.compose.runtime.rememberCoroutineScope
 import com.notemusicali.scores.extractMusicXmlFromBytes
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.launch
+import kotlinx.coroutines.swing.Swing
+import kotlinx.coroutines.withContext
+import java.awt.KeyboardFocusManager
 import javax.swing.JFileChooser
 import javax.swing.filechooser.FileNameExtensionFilter
 
 @Composable
 actual fun rememberFilePickerLauncher(
     mimeTypes: List<String>,
-    onFileContent: (String) -> Unit,
+    onFileContent: (fileName: String, content: String) -> Unit,
 ): () -> Unit {
     val scope = rememberCoroutineScope()
     return {
-        scope.launch(Dispatchers.Default) {
+        // I dialoghi Swing vivono solo sull'Event Dispatch Thread; mostrarli da
+        // un thread di background inchioda l'app su macOS
+        scope.launch(Dispatchers.Swing) {
             val chooser = JFileChooser().apply {
                 fileFilter = FileNameExtensionFilter("MusicXML files", "xml", "musicxml", "mxl")
                 dialogTitle = "Seleziona file MusicXML"
             }
-            val result = chooser.showOpenDialog(null)
+            val parent = KeyboardFocusManager.getCurrentKeyboardFocusManager().activeWindow
+            val result = chooser.showOpenDialog(parent)
             if (result == JFileChooser.APPROVE_OPTION) {
+                val file = chooser.selectedFile
+                // Lettura e unzip fuori dall'EDT
+                val content = withContext(Dispatchers.Default) {
                     try {
-                    val bytes = chooser.selectedFile.readBytes()
-                    val content = extractMusicXmlFromBytes(bytes)
-                    if (content != null) {
-                        onFileContent(content)
-                    }
+                        extractMusicXmlFromBytes(file.readBytes())
                     } catch (_: Exception) {
-                    // File read failed
+                        null
+                    }
+                }
+                // Callback di nuovo sull'EDT: aggiorna stato Compose e naviga
+                if (content != null) {
+                    onFileContent(file.name, content)
                 }
             }
         }

shared/src/desktopMain/kotlin/com/notemusicali/ui/components/FolderPicker.desktop.kt

@@ -1,6 +1,7 @@
 package com.notemusicali.ui.components
 
 import androidx.compose.runtime.Composable
+import java.awt.KeyboardFocusManager
 import javax.swing.JFileChooser
 
 @Composable
@@ -12,7 +13,9 @@ actual fun rememberFolderPickerLauncher(
             fileSelectionMode = JFileChooser.DIRECTORIES_ONLY
             dialogTitle = "Scegli cartella spartiti"
         }
-        if (chooser.showOpenDialog(null) == JFileChooser.APPROVE_OPTION) {
+        // Parent = finestra attiva, così il dialogo non finisce dietro l'app
+        val parent = KeyboardFocusManager.getCurrentKeyboardFocusManager().activeWindow
+        if (chooser.showOpenDialog(parent) == JFileChooser.APPROVE_OPTION) {
             val file = chooser.selectedFile
             onFolderSelected(file.absolutePath, file.name)
         }

shared/src/desktopMain/kotlin/com/notemusicali/ui/scan/CameraCapture.desktop.kt

@@ -18,6 +18,8 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.notemusicali.scan.PlatformImage
 import kotlinx.coroutines.Dispatchers
+import java.awt.KeyboardFocusManager
+import kotlinx.coroutines.swing.Swing
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import javax.imageio.ImageIO
@@ -45,9 +47,17 @@ actual fun CameraCapture(
             )
             Button(
                 onClick = {
-                    scope.launch(Dispatchers.Default) {
-                        val image = pickImageFile() ?: return@launch
-                        withContext(Dispatchers.Main) { onImageCaptured(image) }
+                    // Dialogo sull'EDT (Swing), decodifica dell'immagine su Default
+                    scope.launch(Dispatchers.Swing) {
+                        val file = pickImageFile() ?: return@launch
+                        val image = withContext(Dispatchers.Default) {
+                            try {
+                                ImageIO.read(file)
+                            } catch (_: Exception) {
+                                null
+                            }
+                        } ?: return@launch
+                        onImageCaptured(image)
                     }
                 },
                 colors = ButtonDefaults.buttonColors(
@@ -61,16 +71,13 @@ actual fun CameraCapture(
     }
 }
 
-private fun pickImageFile(): PlatformImage? {
+private fun pickImageFile(): java.io.File? {
     val chooser = JFileChooser().apply {
         dialogTitle = "Scegli l'immagine dello spartito"
         fileFilter = FileNameExtensionFilter("Immagini (PNG, JPEG)", "png", "jpg", "jpeg")
         isMultiSelectionEnabled = false
     }
-    if (chooser.showOpenDialog(null) != JFileChooser.APPROVE_OPTION) return null
-    return try {
-        ImageIO.read(chooser.selectedFile)
-    } catch (_: Exception) {
-        null
-    }
+    val parent = KeyboardFocusManager.getCurrentKeyboardFocusManager().activeWindow
+    if (chooser.showOpenDialog(parent) != JFileChooser.APPROVE_OPTION) return null
+    return chooser.selectedFile
 }

shared/src/iosMain/kotlin/com/notemusicali/ui/components/FilePicker.ios.kt

@@ -22,14 +22,14 @@ private var retainedFileDelegate: FilePickerDelegate? = null
 @Composable
 actual fun rememberFilePickerLauncher(
     mimeTypes: List<String>,
-    onFileContent: (String) -> Unit,
+    onFileContent: (fileName: String, content: String) -> Unit,
 ): () -> Unit {
     return {
         presentFilePicker(onFileContent)
     }
 }
 
-private fun presentFilePicker(onFileContent: (String) -> Unit) {
+private fun presentFilePicker(onFileContent: (fileName: String, content: String) -> Unit) {
     @Suppress("DEPRECATION")
     val rootVC = UIApplication.sharedApplication.keyWindow?.rootViewController ?: return
     val topVC = topPresentedViewController(rootVC)
@@ -56,7 +56,7 @@ private fun topPresentedViewController(vc: UIViewController): UIViewController {
 }
 
 private class FilePickerDelegate(
-    private val onFileContent: (String) -> Unit,
+    private val onFileContent: (fileName: String, content: String) -> Unit,
 ) : NSObject(), UIDocumentPickerDelegateProtocol {
 
     @OptIn(ExperimentalForeignApi::class)
@@ -71,7 +71,7 @@ private class FilePickerDelegate(
             val data = NSData.dataWithContentsOfURL(url) ?: return
             val bytes = data.toByteArray()
             val content = extractMusicXmlFromBytes(bytes) ?: return
-            onFileContent(content)
+            onFileContent(url.lastPathComponent ?: "Import", content)
         } finally {
             if (accessing) url.stopAccessingSecurityScopedResource()
         }