wire TOML export/import to iOS session browser

cue-ios/CueIOS/Views/SessionView.swift

@@ -1,5 +1,6 @@
 import SwiftUI
 import GRDB
+import UniformTypeIdentifiers
 
 struct SessionView: View {
     @Bindable var state: AppState
@@ -191,6 +192,9 @@ struct SessionDetailView: View {
     @State private var editing = false
     @State private var editLabel = ""
     @State private var editNotes = ""
+    @State private var showingFileImporter = false
+    @State private var showingShareSheet = false
+    @State private var exportFileURL: URL?
 
     var body: some View {
         VStack(alignment: .leading, spacing: 0) {
@@ -201,6 +205,16 @@ struct SessionDetailView: View {
         .onAppear { loadMeasurements() }
         .onChange(of: session.id) { loadMeasurements() }
         .sheet(isPresented: $editing) { editSheet }
+        .sheet(isPresented: $showingShareSheet) {
+            if let url = exportFileURL {
+                ShareSheet(items: [url])
+            }
+        }
+        .fileImporter(
+            isPresented: $showingFileImporter,
+            allowedContentTypes: [.plainText],
+            onCompletion: handleImportedFile
+        )
     }
 
     private func loadMeasurements() {
@@ -208,6 +222,40 @@ struct SessionDetailView: View {
         measurements = (try? Storage.shared.fetchMeasurements(sessionId: sid)) ?? []
     }
 
+    private func exportSession() {
+        guard let sid = session.id else { return }
+        do {
+            let toml = try Storage.shared.exportSession(sid)
+            let name = (session.label ?? "session").replacingOccurrences(of: " ", with: "_")
+            let url = FileManager.default.temporaryDirectory.appendingPathComponent("\(name).toml")
+            try toml.write(to: url, atomically: true, encoding: .utf8)
+            exportFileURL = url
+            showingShareSheet = true
+        } catch {
+            state.status = "Export failed: \(error.localizedDescription)"
+        }
+    }
+
+    private func handleImportedFile(_ result: Result<URL, Error>) {
+        switch result {
+        case .success(let url):
+            guard url.startAccessingSecurityScopedResource() else {
+                state.status = "Cannot access file"
+                return
+            }
+            defer { url.stopAccessingSecurityScopedResource() }
+            do {
+                let toml = try String(contentsOf: url, encoding: .utf8)
+                let _ = try Storage.shared.importSession(from: toml)
+                state.status = "Session imported"
+            } catch {
+                state.status = "Import failed: \(error.localizedDescription)"
+            }
+        case .failure(let error):
+            state.status = "File error: \(error.localizedDescription)"
+        }
+    }
+
     private var header: some View {
         VStack(alignment: .leading, spacing: 4) {
             HStack {
@@ -222,6 +270,14 @@ struct SessionDetailView: View {
                     Image(systemName: "pencil.circle")
                         .imageScale(.large)
                 }
+                Button(action: { exportSession() }) {
+                    Image(systemName: "square.and.arrow.up")
+                        .imageScale(.large)
+                }
+                Button(action: { showingFileImporter = true }) {
+                    Image(systemName: "square.and.arrow.down")
+                        .imageScale(.large)
+                }
             }
             HStack {
                 Text(session.startedAt, style: .date)
@@ -368,3 +424,11 @@ struct MeasurementRow: View {
         return (try? Storage.shared.dataPointCount(measurementId: mid)) ?? 0
     }
 }
+
+struct ShareSheet: UIViewControllerRepresentable {
+    let items: [Any]
+    func makeUIViewController(context: Context) -> UIActivityViewController {
+        UIActivityViewController(activityItems: items, applicationActivities: nil)
+    }
+    func updateUIViewController(_ vc: UIActivityViewController, context: Context) {}
+}