refactor: move spa to frontend folder

frontend/spa/src/helpers.js

@@ -0,0 +1,30 @@
+export function isNotEmpty(value) {
+    if (value === null || value === undefined) return false;
+
+    if (Array.isArray(value)) return value.length > 0;
+
+    if (typeof value === 'object') return Object.keys(value).length > 0;
+
+    if (typeof value === 'string') return value.trim() !== '';
+
+    return true; // для чисел, булевых и т.п.
+}
+
+export function formatPrice(raw) {
+    if (raw === null || raw === undefined) return '';
+
+    const str = String(raw).trim();
+    const match = str.match(/^([+-]?)(\d+(?:\.\d+)?)/);
+    if (!match) return '';
+
+    const sign = match[1] || '';
+    const num = parseFloat(match[2]);
+
+    if (isNaN(num) || num === 0) return '';
+
+    const formatted = Math.round(num)
+        .toString()
+        .replace(/\B(?=(\d{3})+(?!\d))/g, ' ');
+
+    return `${sign}${formatted}`;
+}