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Next step
1) Make a Demo video
2) Deploy

client/src/app/api/documents/[id]/export/route.ts

@@ -0,0 +1,93 @@
+import { NextRequest, NextResponse } from "next/server";
+import { getServerSession } from "next-auth";
+import { authOptions } from "@/app/api/auth/[...nextauth]/route";
+import { prisma } from "@/lib/prisma";
+import { readdir, readFile } from "fs/promises";
+import path from "path";
+import { PDFDocument } from "pdf-lib";
+
+type ExportType = "original" | "pixel";
+
+function parsePageNumber(fileName: string): number {
+  const match = fileName.match(/^page_(\d+)\.png$/);
+  return match ? Number(match[1]) : Number.MAX_SAFE_INTEGER;
+}
+
+export async function GET(
+  req: NextRequest,
+  { params }: { params: Promise<{ id: string }> }
+) {
+  const session = await getServerSession(authOptions);
+  if (!session?.user?.email) {
+    return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
+  }
+
+  const { id } = await params;
+  const typeParam = req.nextUrl.searchParams.get("type");
+  const type: ExportType = typeParam === "pixel" ? "pixel" : "original";
+
+  const doc = await prisma.pdfDocument.findUnique({ where: { id } });
+  if (!doc) {
+    return NextResponse.json({ error: "Document not found" }, { status: 404 });
+  }
+
+  const user = await prisma.user.findUnique({
+    where: { email: session.user.email },
+  });
+  if (!user || doc.userId !== user.id) {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  try {
+    const resultsDir = path.join(
+      process.cwd(),
+      "public",
+      "results",
+      user.id,
+      id,
+      type
+    );
+
+    const files = (await readdir(resultsDir))
+      .filter((fileName) => /^page_\d+\.png$/.test(fileName))
+      .sort((a, b) => parsePageNumber(a) - parsePageNumber(b));
+
+    if (files.length === 0) {
+      return NextResponse.json(
+        { error: `No ${type} pages found. Render/process the document first.` },
+        { status: 409 }
+      );
+    }
+
+    const pdfDoc = await PDFDocument.create();
+
+    for (const fileName of files) {
+      const imagePath = path.join(resultsDir, fileName);
+      const imageBytes = await readFile(imagePath);
+      const pngImage = await pdfDoc.embedPng(imageBytes);
+      const page = pdfDoc.addPage([pngImage.width, pngImage.height]);
+      page.drawImage(pngImage, {
+        x: 0,
+        y: 0,
+        width: pngImage.width,
+        height: pngImage.height,
+      });
+    }
+
+    const pdfBytes = await pdfDoc.save();
+    const safeBaseName = doc.originalName.replace(/\.pdf$/i, "").replace(/\s+/g, "_");
+    const outputName = `${safeBaseName}_${type}.pdf`;
+
+    return new NextResponse(Buffer.from(pdfBytes), {
+      status: 200,
+      headers: {
+        "Content-Type": "application/pdf",
+        "Content-Disposition": `attachment; filename=\"${outputName}\"`,
+        "Cache-Control": "no-store",
+      },
+    });
+  } catch (error) {
+    console.error("PDF export error:", error);
+    return NextResponse.json({ error: "Failed to export PDF" }, { status: 500 });
+  }
+}