feat(settings): implement config migration and deep merge for backward compatibility

src/app/settings.ts

@@ -40,6 +40,83 @@ const SAVED_INDICATOR_MS = 1500;
 
 export type SettingsConfig = Record<string, any>;
 
+const BUNDLED_VERSION: string = (bundledConfig as any).version ?? '0';
+
+// ─── Config migration ─────────────────────────────────────────────────────────
+
+/** Recursively fill missing keys/sub-objects from `defaults` into `target`. */
+function deepMergeDefaults(target: Record<string, any>, defaults: Record<string, any>): Record<string, any> {
+  const result = { ...target };
+  for (const [k, v] of Object.entries(defaults)) {
+    if (k === 'version') continue;
+    if (!(k in result)) {
+      result[k] = v;
+    } else if (
+      v !== null && typeof v === 'object' && !Array.isArray(v) &&
+      result[k] !== null && typeof result[k] === 'object' && !Array.isArray(result[k])
+    ) {
+      result[k] = deepMergeDefaults(result[k] as Record<string, any>, v as Record<string, any>);
+    }
+  }
+  return result;
+}
+
+/**
+ * Migrate a config loaded from an older format to the current structure.
+ *
+ * Handles:
+ *  - Top-level renames: general→preferences, iec_config→settings
+ *  - Sub-key renames inside settings: drive_rom→drive_roms
+ *  - Moving peripherals into devices: hardware.userport, cassette, bluetooth, modem
+ *  - Old devices.json shape: { iec: { devices:{} } } → devices.iec
+ *  - Deep-merging any missing keys from the bundled defaults
+ */
+function migrateConfig(raw: Record<string, any>): Record<string, any> {
+  let c = { ...raw };
+
+  // Top-level key renames
+  if ('general'    in c && !('preferences' in c)) { c.preferences = c.general;    delete c.general; }
+  if ('iec_config' in c && !('settings'    in c)) { c.settings    = c.iec_config; delete c.iec_config; }
+
+  // settings sub-key rename
+  if (c.settings && typeof c.settings === 'object') {
+    const s = { ...c.settings } as Record<string, any>;
+    if ('drive_rom' in s && !('drive_roms' in s)) { s.drive_roms = s.drive_rom; delete s.drive_rom; }
+    c.settings = s;
+  }
+
+  // Old devices.json merged as config.iec = { devices:{} } — move to config.devices.iec
+  if (c.iec && typeof c.iec === 'object') {
+    if (!c.devices) c.devices = {};
+    const oldIec = c.iec as Record<string, any>;
+    if ('devices' in oldIec && !c.devices.iec) c.devices.iec = oldIec.devices;
+    delete c.iec;
+  }
+
+  // Move peripheral config into devices
+  if (!c.devices) c.devices = {};
+  if (c.hardware && typeof c.hardware === 'object') {
+    const hw = c.hardware as Record<string, any>;
+    if (hw.userport  !== undefined && c.devices.userport === undefined) c.devices.userport = hw.userport;
+    if (hw.ps2       !== undefined && c.devices.ps2      === undefined) c.devices.ps2      = hw.ps2;
+    delete c.hardware;
+  }
+  if (c.cassette  && !c.devices.cassette)  { c.devices.cassette  = c.cassette;  delete c.cassette; }
+  if (c.bluetooth && !c.devices.bluetooth) { c.devices.bluetooth = c.bluetooth; delete c.bluetooth; }
+  if (c.modem     && !c.devices.modem)     { c.devices.modem     = c.modem;     delete c.modem; }
+  if ('boip' in c) delete c.boip;
+
+  // Fill any missing keys/sub-objects from bundled defaults
+  c = deepMergeDefaults(c, bundledConfig as Record<string, any>);
+
+  // Stamp the current version
+  c.version = BUNDLED_VERSION;
+
+  return c;
+}
+
+// ─── I/O helpers ──────────────────────────────────────────────────────────────
+
 /** Try primary path first, fall back to secondary. Returns null if both fail. */
 async function getTextWithFallback(primary: string, fallback: string): Promise<string | null> {
   try { return await getFileContents(primary).then(b => b.text()); } catch { /* try fallback */ }
@@ -47,8 +124,14 @@ async function getTextWithFallback(primary: string, fallback: string): Promise<s
   return null;
 }
 
+export interface ReadSettingsResult {
+  config: SettingsConfig;
+  /** True when the loaded config was an older version and has been migrated. */
+  migrated: boolean;
+}
+
 /** Read both config files from the WebDAV server and merge them. Returns null on failure. */
-export async function readSettings(): Promise<SettingsConfig | null> {
+export async function readSettings(): Promise<ReadSettingsResult | null> {
   try {
     // Mirror firmware priority: /sd/.sys/ first, fall back to /.sys/
     const [configText, devicesText] = await Promise.all([
@@ -56,10 +139,10 @@ export async function readSettings(): Promise<SettingsConfig | null> {
       getTextWithFallback('/sd' + DEVICES_PATH,  DEVICES_PATH),
     ]);
     if (!configText) return null;
-    const config = JSON.parse(configText);
+    let config = JSON.parse(configText) as Record<string, any>;
     if (!config || typeof config !== 'object') return null;
     if (devicesText) {
-      const devices = JSON.parse(devicesText);
+      const devices = JSON.parse(devicesText) as Record<string, any>;
       if (devices && typeof devices === 'object') {
         // One-level deep merge: devices.json keys are merged into matching
         // top-level objects in config (e.g. devices.devices.iec → config.devices.iec).
@@ -73,7 +156,9 @@ export async function readSettings(): Promise<SettingsConfig | null> {
         }
       }
     }
-    return config as SettingsConfig;
+    const needsMigration = !config.version || config.version !== BUNDLED_VERSION;
+    if (needsMigration) config = migrateConfig(config);
+    return { config: config as SettingsConfig, migrated: needsMigration };
   } catch {
     return null;
   }
@@ -164,10 +249,30 @@ export function useSettings(): UseSettingsResult {
 
   const load = useCallback(async () => {
     setSaveStatus('loading');
-    const fromServer = await readSettings();
-    if (fromServer) {
-      configRef.current = fromServer;
-      setConfigState(fromServer);
+    const result = await readSettings();
+    if (result) {
+      configRef.current = result.config;
+      setConfigState(result.config);
+      if (result.migrated) {
+        // Persist the migrated config immediately so the device is updated.
+        setSaveStatus('saving');
+        try {
+          await writeSettings(result.config);
+          setSaveStatus('saved');
+          savedTimerRef.current = window.setTimeout(() => {
+            setSaveStatus((s) => (s === 'saved' ? 'idle' : s));
+          }, SAVED_INDICATOR_MS);
+        } catch {
+          // If the write fails, mark dirty so the save-status badge appears.
+          dirtyRef.current = true;
+          pendingRef.current = 1;
+          setPendingCount(1);
+          setSaveStatus('unsaved');
+        }
+        loadedRef.current = true;
+        setLoaded(true);
+        return;
+      }
     }
     loadedRef.current = true;
     setLoaded(true);

src/imports/config.json

@@ -1,4 +1,5 @@
 {
+  "version": "0.5.0",
   "preferences": {
     "appearance": "auto",
     "language": "en",