Added export/import features

src/lib/day.svelte.js

@@ -15,13 +15,14 @@ import {
   getEntries,
   getHistory,
   getLastClosedDay,
+  importBackup,
   patchDay,
   patchEntry,
   putDay,
   setEntryStart,
 } from './db.js';
 import { buildModel, suggestClients, suggestTasks, TRANSPORT_TASK } from './predict.js';
-import { settings } from './settings.svelte.js';
+import { loadSettings, settings } from './settings.svelte.js';
 import { atLocalTime, HOUR, localDateKey, roundTs, weekday } from './time.js';
 
 export const dayState = $state({
@@ -37,6 +38,8 @@ export const dayState = $state({
   /** True once the configured end time has passed and the worker has not answered. */
   needsClosePrompt: false,
   loaded: false,
+  /** Blocks clock reconciliation while an imported snapshot is installed. */
+  importing: false,
 });
 
 export const running = () => dayState.entries.find((e) => e.endTs == null) ?? null;
@@ -45,12 +48,24 @@ export const running = () => dayState.entries.find((e) => e.endTs == null) ?? nu
 
 /** Retention runs once per session, not on every 30 s tick. */
 let cleanedUpFor = null;
+const pendingReconciliations = new Set();
 
 /**
  * Bring stored state in line with the clock. Safe to call often — it is invoked on
  * load, on tab focus, and from a 30 s tick.
  */
-export async function reconcile(now = Date.now()) {
+export function reconcile(now = Date.now()) {
+  if (dayState.importing) return Promise.resolve();
+  const pending = reconcileDay(now);
+  pendingReconciliations.add(pending);
+  pending.then(
+    () => pendingReconciliations.delete(pending),
+    () => pendingReconciliations.delete(pending),
+  );
+  return pending;
+}
+
+async function reconcileDay(now) {
   dayState.today = localDateKey(now);
 
   // Applying retention here is what makes the setting mean anything; leaving it to
@@ -203,6 +218,34 @@ export async function removeEntry(id) {
   await refresh();
 }
 
+/**
+ * Apply an imported dataset, then rebuild everything that was derived from the old
+ * one: the settings rune (replace mode adopts the file's settings), the prediction
+ * model, and the resume.
+ *
+ * @param {{days: Array, entries: Array, settings: object|null}} payload
+ * @param {'merge'|'replace'} mode
+ */
+export async function applyImport(payload, mode) {
+  if (dayState.importing) throw new Error('Un import est déjà en cours.');
+  dayState.importing = true;
+  try {
+    // Let an already-running clock operation finish before replacing its data.
+    // The guard above prevents subsequent ticks/focus events during the import.
+    await Promise.allSettled([...pendingReconciliations]);
+    const result = await importBackup(payload, mode);
+    if (mode === 'replace') await loadSettings();
+    // Do not immediately purge old imported days or create a new working day.
+    // Normal retention resumes next session/day; manual purge remains available.
+    dayState.today = localDateKey();
+    cleanedUpFor = dayState.today;
+    await refresh();
+    return result;
+  } finally {
+    dayState.importing = false;
+  }
+}
+
 export async function endDay(now = Date.now()) {
   if (!dayState.day) return;
   const date = dayState.day.date;