added bulk price update feature, allowing users to select multiple products and apply a new price to all of them at once. The bulk action bar now shows the count of selected items and enables the "OK" button only when at least one product is selected.

app.py

@@ -189,6 +189,27 @@ def scan():
 def serve_cache(filename):
     return send_from_directory(CACHE_DIR, filename)
 
+@app.route('/bulk_price_update', methods=['POST'])
+@login_required
+def bulk_price_update():
+    data = request.get_json()
+    barcodes = data.get('barcodes', [])
+    new_price = data.get('new_price')
+
+    if not barcodes or new_price is None:
+        return jsonify({"error": "Missing data"}), 400
+
+    try:
+        with sqlite3.connect(DB_FILE) as conn:
+            # Use executemany for efficiency
+            params = [(float(new_price), b) for b in barcodes]
+            conn.executemany('UPDATE products SET price = ? WHERE barcode = ?', params)
+            conn.commit()
+        return jsonify({"status": "success"}), 200
+    except Exception as e:
+        print(f"Bulk update failed: {e}")
+        return jsonify({"error": str(e)}), 500
+
 if __name__ == '__main__':
     init_db()
     socketio.run(app, host='0.0.0.0', port=5000, debug=True)