feat(grid): implement product streaming with JSON chunks for grid client

src/app/api/grid/rows/route.ts

@@ -0,0 +1,65 @@
+import { NextRequest } from "next/server";
+import { getProductRows } from "@/features/grid/api/get-product-rows";
+import type { GridFilters } from "@/types/grid";
+
+export const dynamic = "force-dynamic";
+
+function writeNdjson(controller: ReadableStreamDefaultController<Uint8Array>, value: unknown) {
+    controller.enqueue(new TextEncoder().encode(`${JSON.stringify(value)}\n`));
+}
+
+export async function GET(request: NextRequest) {
+    const searchParams = request.nextUrl.searchParams;
+    const codeFournisseur = searchParams.get("fournisseur");
+
+    if (!codeFournisseur) {
+        return Response.json({ error: "Missing fournisseur" }, { status: 400 });
+    }
+
+    const magasin = searchParams.get("magasin") ?? "TOTAL";
+    const chunkSize = Math.max(50, Math.min(500, Number(searchParams.get("chunkSize") ?? 150)));
+    const filters: Partial<GridFilters> = {
+        code1: searchParams.get("code1"),
+        code2: searchParams.get("code2"),
+        code3: searchParams.get("code3"),
+    };
+    const forceRefresh = searchParams.get("refresh") === "1";
+
+    const stream = new ReadableStream<Uint8Array>({
+        async start(controller) {
+            try {
+                writeNdjson(controller, { type: "start", loaded: 0, total: null });
+                const rows = await getProductRows({ codeFournisseur, magasin, filters, forceRefresh });
+                const total = rows.length;
+
+                for (let start = 0; start < total; start += chunkSize) {
+                    const chunk = rows.slice(start, start + chunkSize);
+                    writeNdjson(controller, {
+                        type: "chunk",
+                        rows: chunk,
+                        loaded: Math.min(start + chunk.length, total),
+                        total,
+                    });
+                    await new Promise((resolve) => setTimeout(resolve, 0));
+                }
+
+                writeNdjson(controller, { type: "done", loaded: total, total });
+            } catch (error) {
+                writeNdjson(controller, {
+                    type: "error",
+                    error: error instanceof Error ? error.message : "Unknown error",
+                });
+            } finally {
+                controller.close();
+            }
+        },
+    });
+
+    return new Response(stream, {
+        headers: {
+            "Content-Type": "application/x-ndjson; charset=utf-8",
+            "Cache-Control": "no-store",
+            "X-Accel-Buffering": "no",
+        },
+    });
+}