mgply09ox: Publish an image post through a server upload pipeline

src/app/api/posts/route.ts

@@ -1,17 +1,43 @@
 import { NextResponse, type NextRequest } from "next/server";
 import { SESSION_COOKIE } from "@/lib/cookie";
 import { createTextPost } from "@/lib/post-create";
+import { createImagePost } from "@/lib/post-media";
 
-// POST /api/posts  { content }
-// Creates a public text draft on the feed, then publishes it. Returns { id }.
-// The create call can report status "draft" for a post already on the home
-// feed, so the browser reloads the first page and confirms the id there.
+// POST /api/posts
+//   - JSON  { content }                -> public text post
+//   - multipart/form-data content+file -> public image post (one file)
+// Both create a public draft on the feed, then publish it, and return { id }.
+// For an image the server also uploads the bytes to a presigned URL and confirms
+// the upload; the browser never receives the feed token. The create call can
+// report status "draft" for a post already on the home feed, so the browser
+// reloads the first page and confirms the id there.
 // 401 { error: "sign_in" } without a session.
 
 export const runtime = "nodejs";
 
 export async function POST(req: NextRequest) {
   const sessionId = req.cookies.get(SESSION_COOKIE)?.value;
+  const contentType = req.headers.get("content-type") ?? "";
+
+  if (contentType.includes("multipart/form-data")) {
+    let content = "";
+    let file: File | null = null;
+    try {
+      const form = await req.formData();
+      const c = form.get("content");
+      content = typeof c === "string" ? c : "";
+      const f = form.get("file");
+      file = f instanceof File ? f : null;
+    } catch {
+      return NextResponse.json({ error: "bad_file" }, { status: 400 });
+    }
+    const result = await createImagePost(sessionId, content, file);
+    if (!result.ok) {
+      return NextResponse.json({ error: result.error }, { status: result.status });
+    }
+    return NextResponse.json({ id: result.id });
+  }
+
   let content: unknown = null;
   try {
     content = ((await req.json()) as { content?: unknown }).content;