Persist selections and compile song output

Sources/MusicAssistantApp/Presentation/InstrumentBrowserView.swift

@@ -3,18 +3,23 @@ import SwiftUI
 
 struct InstrumentBrowserView: View {
     @Binding private var project: SongProject
+    private let saveProject: (SongProject) async -> Bool
     private let catalog: LocalInstrumentCatalog
 
     @State private var searchText = ""
     @State private var selectedFamilyCategory: String?
     @State private var selectedRegionOrigin: String?
+    @State private var hasUnsavedSelectionChanges = false
+    @State private var isSaving = false
     @Environment(\.dismiss) private var dismiss
 
     init(
         project: Binding<SongProject>,
+        saveProject: @escaping (SongProject) async -> Bool = { _ in true },
         catalog: LocalInstrumentCatalog = LocalInstrumentCatalog()
     ) {
         _project = project
+        self.saveProject = saveProject
         self.catalog = catalog
     }
 
@@ -81,12 +86,33 @@ struct InstrumentBrowserView: View {
             .toolbar {
                 ToolbarItem(placement: .cancellationAction) {
                     Button("Done") {
-                        dismiss()
+                        Task {
+                            await saveSelectionChangesIfNeeded()
+                            dismiss()
+                        }
+                    }
+                    .disabled(isSaving)
+                }
+
+                if isSaving {
+                    ToolbarItem(placement: .status) {
+                        ProgressView()
+                            .controlSize(.small)
                     }
                 }
             }
         }
         .frame(minWidth: 460, minHeight: 520)
+        .onDisappear {
+            guard hasUnsavedSelectionChanges, !isSaving else { return }
+
+            let projectToSave = project
+            hasUnsavedSelectionChanges = false
+
+            Task {
+                _ = await saveProject(projectToSave)
+            }
+        }
     }
 
     private func selectionBinding(for instrument: InstrumentCatalogItem) -> Binding<Bool> {
@@ -98,8 +124,18 @@ struct InstrumentBrowserView: View {
                 isSelected: isSelected,
                 variant: instrument.name
             )
+            hasUnsavedSelectionChanges = true
         }
     }
+
+    private func saveSelectionChangesIfNeeded() async {
+        guard hasUnsavedSelectionChanges else { return }
+
+        isSaving = true
+        let didSave = await saveProject(project)
+        hasUnsavedSelectionChanges = !didSave
+        isSaving = false
+    }
 }
 
 #Preview {