feat: add stuff

apps/api/src/devices/stock-sync.ts

@@ -0,0 +1,54 @@
+import { plainToInstance } from 'class-transformer';
+import { validateSync } from 'class-validator';
+import { ReportedProductDto, StockAdjustmentResultDto } from './dto/stock-sync.dto';
+import { describe } from './tab-events';
+
+export type Rejected = { id: string | null; reason: string };
+
+/**
+ * Validates entries one by one, like tab events: one bad product or result is skipped on its own
+ * instead of failing the sync (and with it the open tabs and sales).
+ */
+function parseEach<T extends object>(cls: new () => T, raw: unknown[]): { accepted: T[]; rejected: Rejected[] } {
+  const accepted: T[] = [];
+  const rejected: Rejected[] = [];
+
+  for (const value of raw) {
+    const id = typeof (value as { id?: unknown })?.id === 'string' ? (value as { id: string }).id : null;
+    if (typeof value !== 'object' || value === null || Array.isArray(value)) {
+      rejected.push({ id, reason: 'must be an object' });
+      continue;
+    }
+    const entry = plainToInstance(cls, value);
+    const errors = validateSync(entry, { whitelist: true });
+    if (errors.length > 0) {
+      rejected.push({ id, reason: describe(errors) });
+      continue;
+    }
+    accepted.push(entry);
+  }
+
+  return { accepted, rejected };
+}
+
+export function parseProducts(raw: unknown[]) {
+  const { accepted, rejected } = parseEach(ReportedProductDto, raw);
+  // A duplicated id would make the upserts fight; the last one reported wins
+  const byId = new Map(accepted.map((product) => [product.id, product]));
+  return {
+    products: [...byId.values()].map((p) => ({
+      id: p.id,
+      name: p.name.trim(),
+      category: p.category?.trim() || null,
+      priceInCents: p.priceInCents,
+      stock: p.stock ?? null,
+    })),
+    rejected,
+  };
+}
+
+export type ParsedProduct = ReturnType<typeof parseProducts>['products'][number];
+
+export function parseStockResults(raw: unknown[]) {
+  return parseEach(StockAdjustmentResultDto, raw);
+}