diff --git a/pos/static/js/sync-engine.js b/pos/static/js/sync-engine.js
new file mode 100644
index 0000000..a0fa1a7
--- /dev/null
+++ b/pos/static/js/sync-engine.js
@@ -0,0 +1,204 @@
+// /home/Autopartes/pos/static/js/sync-engine.js
+// Nexus POS — Offline sync engine using IndexedDB
+
+(function () {
+ 'use strict';
+
+ var DB_NAME = 'nexus_pos_offline';
+ var DB_VERSION = 1;
+ var QUEUE_STORE = 'sync_queue';
+ var INVENTORY_STORE = 'inventory_cache';
+
+ var db = null;
+
+ // ─── IndexedDB setup ──────────────────────────────────────────
+ function openDB() {
+ return new Promise(function (resolve, reject) {
+ if (db) { resolve(db); return; }
+ var req = indexedDB.open(DB_NAME, DB_VERSION);
+ req.onupgradeneeded = function (e) {
+ var d = e.target.result;
+ if (!d.objectStoreNames.contains(QUEUE_STORE)) {
+ d.createObjectStore(QUEUE_STORE, { keyPath: 'id', autoIncrement: true });
+ }
+ if (!d.objectStoreNames.contains(INVENTORY_STORE)) {
+ var inv = d.createObjectStore(INVENTORY_STORE, { keyPath: 'item_id' });
+ inv.createIndex('sku', 'sku', { unique: false });
+ inv.createIndex('name', 'name', { unique: false });
+ }
+ };
+ req.onsuccess = function (e) {
+ db = e.target.result;
+ resolve(db);
+ };
+ req.onerror = function () { reject(req.error); };
+ });
+ }
+
+ // ─── Queue operations for offline replay ──────────────────────
+ function queueOperation(url, method, body) {
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(QUEUE_STORE, 'readwrite');
+ tx.objectStore(QUEUE_STORE).add({
+ url: url,
+ method: method,
+ body: body || null,
+ timestamp: Date.now()
+ });
+ tx.oncomplete = function () { resolve(); };
+ tx.onerror = function () { reject(tx.error); };
+ });
+ });
+ }
+
+ // ─── Process queued operations ────────────────────────────────
+ function processQueue() {
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(QUEUE_STORE, 'readonly');
+ var req = tx.objectStore(QUEUE_STORE).getAll();
+ req.onsuccess = function () { resolve(req.result); };
+ req.onerror = function () { reject(req.error); };
+ });
+ }).then(function (ops) {
+ if (!ops.length) return Promise.resolve({ synced: 0 });
+
+ // Replay in order
+ var chain = Promise.resolve();
+ var synced = 0;
+ var failed = 0;
+
+ ops.forEach(function (op) {
+ chain = chain.then(function () {
+ var opts = { method: op.method, headers: { 'Content-Type': 'application/json' } };
+ if (op.body) opts.body = JSON.stringify(op.body);
+
+ return fetch(op.url, opts).then(function (resp) {
+ if (resp.ok) {
+ synced++;
+ return removeFromQueue(op.id);
+ }
+ failed++;
+ }).catch(function () {
+ failed++;
+ });
+ });
+ });
+
+ return chain.then(function () {
+ return { synced: synced, failed: failed, total: ops.length };
+ });
+ });
+ }
+
+ function removeFromQueue(id) {
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(QUEUE_STORE, 'readwrite');
+ tx.objectStore(QUEUE_STORE).delete(id);
+ tx.oncomplete = function () { resolve(); };
+ tx.onerror = function () { reject(tx.error); };
+ });
+ });
+ }
+
+ function getQueueCount() {
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(QUEUE_STORE, 'readonly');
+ var req = tx.objectStore(QUEUE_STORE).count();
+ req.onsuccess = function () { resolve(req.result); };
+ req.onerror = function () { reject(req.error); };
+ });
+ });
+ }
+
+ // ─── Inventory cache ──────────────────────────────────────────
+ function cacheInventory() {
+ return fetch('/pos/api/sync/inventory').then(function (resp) {
+ if (!resp.ok) throw new Error('Sync inventory failed: ' + resp.status);
+ return resp.json();
+ }).then(function (data) {
+ var items = data.items || [];
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(INVENTORY_STORE, 'readwrite');
+ var store = tx.objectStore(INVENTORY_STORE);
+ store.clear();
+ items.forEach(function (item) { store.put(item); });
+ tx.oncomplete = function () { resolve(items.length); };
+ tx.onerror = function () { reject(tx.error); };
+ });
+ });
+ });
+ }
+
+ function getCachedInventory(query) {
+ return openDB().then(function (d) {
+ return new Promise(function (resolve, reject) {
+ var tx = d.transaction(INVENTORY_STORE, 'readonly');
+ var req = tx.objectStore(INVENTORY_STORE).getAll();
+ req.onsuccess = function () {
+ var all = req.result;
+ if (!query) { resolve(all); return; }
+
+ var q = query.toLowerCase();
+ var filtered = all.filter(function (item) {
+ return (item.sku && item.sku.toLowerCase().indexOf(q) !== -1) ||
+ (item.name && item.name.toLowerCase().indexOf(q) !== -1) ||
+ (item.barcode && item.barcode.toLowerCase().indexOf(q) !== -1);
+ });
+ resolve(filtered);
+ };
+ req.onerror = function () { reject(req.error); };
+ });
+ });
+ }
+
+ // ─── Connectivity helpers ─────────────────────────────────────
+ function isOnline() {
+ return navigator.onLine;
+ }
+
+ // ─── Auto-sync on reconnect ───────────────────────────────────
+ window.addEventListener('online', function () {
+ console.log('[SyncEngine] Online — processing queue...');
+ processQueue().then(function (result) {
+ if (result.synced > 0) {
+ console.log('[SyncEngine] Synced ' + result.synced + ' operations');
+ }
+ }).catch(function (err) {
+ console.error('[SyncEngine] Queue processing error:', err);
+ });
+ });
+
+ window.addEventListener('offline', function () {
+ console.log('[SyncEngine] Offline — operations will be queued');
+ });
+
+ // Listen for SW sync messages
+ if ('serviceWorker' in navigator) {
+ navigator.serviceWorker.addEventListener('message', function (event) {
+ if (event.data && event.data.type === 'SYNC_REQUESTED') {
+ processQueue();
+ }
+ });
+ }
+
+ // ─── Init DB on load ──────────────────────────────────────────
+ openDB().catch(function (err) {
+ console.error('[SyncEngine] Failed to open IndexedDB:', err);
+ });
+
+ // ─── Public API ───────────────────────────────────────────────
+ window.SyncEngine = {
+ queueOperation: queueOperation,
+ processQueue: processQueue,
+ getQueueCount: getQueueCount,
+ isOnline: isOnline,
+ cacheInventory: cacheInventory,
+ getCachedInventory: getCachedInventory
+ };
+
+})();
diff --git a/pos/static/pwa/icon-192.png b/pos/static/pwa/icon-192.png
new file mode 100644
index 0000000..7f8b6bf
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diff --git a/pos/static/pwa/icon-512.png b/pos/static/pwa/icon-512.png
new file mode 100644
index 0000000..8dd9dd9
Binary files /dev/null and b/pos/static/pwa/icon-512.png differ
diff --git a/pos/static/pwa/manifest.json b/pos/static/pwa/manifest.json
new file mode 100644
index 0000000..faa8969
--- /dev/null
+++ b/pos/static/pwa/manifest.json
@@ -0,0 +1,13 @@
+{
+ "name": "Nexus POS",
+ "short_name": "NexusPOS",
+ "description": "Sistema de Punto de Venta para Refaccionarias",
+ "start_url": "/pos/login",
+ "display": "standalone",
+ "background_color": "#0d0d0d",
+ "theme_color": "#F5A623",
+ "icons": [
+ {"src": "/pos/static/pwa/icon-192.png", "sizes": "192x192", "type": "image/png"},
+ {"src": "/pos/static/pwa/icon-512.png", "sizes": "512x512", "type": "image/png"}
+ ]
+}
diff --git a/pos/static/pwa/sw.js b/pos/static/pwa/sw.js
new file mode 100644
index 0000000..43176d1
--- /dev/null
+++ b/pos/static/pwa/sw.js
@@ -0,0 +1,134 @@
+// /home/Autopartes/pos/static/pwa/sw.js
+// Nexus POS — Service Worker v1
+
+const CACHE_NAME = 'nexus-pos-v1';
+
+const APP_SHELL = [
+ '/pos/login',
+ '/pos/sale',
+ '/pos/catalog',
+ '/pos/inventory',
+ '/pos/customers',
+ '/pos/invoicing',
+ '/pos/accounting',
+ '/pos/dashboard',
+ '/pos/config',
+ '/pos/reports',
+ '/pos/static/css/tokens.css',
+ '/pos/static/css/common.css',
+ '/pos/static/js/app-init.js',
+ '/pos/static/js/sidebar.js',
+ '/pos/static/js/login.js',
+ '/pos/static/js/pos.js',
+ '/pos/static/js/catalog.js',
+ '/pos/static/js/inventory.js',
+ '/pos/static/js/customers.js',
+ '/pos/static/js/invoicing.js',
+ '/pos/static/js/accounting.js',
+ '/pos/static/js/dashboard.js',
+ '/pos/static/js/config.js',
+ '/pos/static/js/reports.js',
+ '/pos/static/js/offline-banner.js',
+ '/pos/static/js/sync-engine.js',
+ '/pos/static/pwa/manifest.json',
+ '/pos/static/pwa/icon-192.png',
+ '/pos/static/pwa/icon-512.png'
+];
+
+// ─── Install: pre-cache app shell ────────────────────────────────
+self.addEventListener('install', function (event) {
+ event.waitUntil(
+ caches.open(CACHE_NAME).then(function (cache) {
+ return cache.addAll(APP_SHELL);
+ }).then(function () {
+ return self.skipWaiting();
+ })
+ );
+});
+
+// ─── Activate: purge old caches ──────────────────────────────────
+self.addEventListener('activate', function (event) {
+ event.waitUntil(
+ caches.keys().then(function (names) {
+ return Promise.all(
+ names.filter(function (n) { return n !== CACHE_NAME; })
+ .map(function (n) { return caches.delete(n); })
+ );
+ }).then(function () {
+ return self.clients.claim();
+ })
+ );
+});
+
+// ─── Fetch strategy ──────────────────────────────────────────────
+self.addEventListener('fetch', function (event) {
+ var url = new URL(event.request.url);
+
+ // API calls → network-first
+ if (url.pathname.indexOf('/pos/api/') !== -1) {
+ event.respondWith(networkFirst(event.request));
+ return;
+ }
+
+ // Everything else → cache-first
+ event.respondWith(cacheFirst(event.request));
+});
+
+function cacheFirst(request) {
+ return caches.match(request).then(function (cached) {
+ if (cached) {
+ // Update cache in background
+ fetch(request).then(function (response) {
+ if (response && response.status === 200) {
+ caches.open(CACHE_NAME).then(function (cache) {
+ cache.put(request, response);
+ });
+ }
+ }).catch(function () { /* offline, ignore */ });
+ return cached;
+ }
+ return fetch(request).then(function (response) {
+ if (response && response.status === 200) {
+ var clone = response.clone();
+ caches.open(CACHE_NAME).then(function (cache) {
+ cache.put(request, clone);
+ });
+ }
+ return response;
+ });
+ });
+}
+
+function networkFirst(request) {
+ return fetch(request).then(function (response) {
+ if (response && response.status === 200) {
+ var clone = response.clone();
+ caches.open(CACHE_NAME).then(function (cache) {
+ cache.put(request, clone);
+ });
+ }
+ return response;
+ }).catch(function () {
+ return caches.match(request);
+ });
+}
+
+// ─── Background Sync ─────────────────────────────────────────────
+self.addEventListener('sync', function (event) {
+ if (event.tag === 'nexus-pos-sync') {
+ event.respondWith && event.waitUntil(
+ self.clients.matchAll().then(function (clients) {
+ clients.forEach(function (client) {
+ client.postMessage({ type: 'SYNC_REQUESTED' });
+ });
+ })
+ );
+ }
+});
+
+// ─── Message handler ─────────────────────────────────────────────
+self.addEventListener('message', function (event) {
+ if (event.data && event.data.type === 'SKIP_WAITING') {
+ self.skipWaiting();
+ }
+});
diff --git a/pos/templates/accounting.html b/pos/templates/accounting.html
index a41d1c7..2548828 100644
--- a/pos/templates/accounting.html
+++ b/pos/templates/accounting.html
@@ -6,6 +6,8 @@
Contabilidad — Nexus Autoparts POS
+
+