feat(routes): add reconnect route

src/app/api/reconnect/[id]/route.ts

@@ -0,0 +1,93 @@
+import SessionManager from '@/lib/session';
+
+export const POST = async (
+  req: Request,
+  { params }: { params: Promise<{ id: string }> },
+) => {
+  try {
+    const { id } = await params;
+
+    const session = SessionManager.getSession(id);
+
+    if (!session) {
+      return Response.json({ message: 'Session not found' }, { status: 404 });
+    }
+
+    const responseStream = new TransformStream();
+    const writer = responseStream.writable.getWriter();
+    const encoder = new TextEncoder();
+
+    const disconnect = session.subscribe((event, data) => {
+      if (event === 'data') {
+        if (data.type === 'block') {
+          writer.write(
+            encoder.encode(
+              JSON.stringify({
+                type: 'block',
+                block: data.block,
+              }) + '\n',
+            ),
+          );
+        } else if (data.type === 'updateBlock') {
+          writer.write(
+            encoder.encode(
+              JSON.stringify({
+                type: 'updateBlock',
+                blockId: data.blockId,
+                patch: data.patch,
+              }) + '\n',
+            ),
+          );
+        } else if (data.type === 'researchComplete') {
+          writer.write(
+            encoder.encode(
+              JSON.stringify({
+                type: 'researchComplete',
+              }) + '\n',
+            ),
+          );
+        }
+      } else if (event === 'end') {
+        writer.write(
+          encoder.encode(
+            JSON.stringify({
+              type: 'messageEnd',
+            }) + '\n',
+          ),
+        );
+        writer.close();
+        disconnect();
+      } else if (event === 'error') {
+        writer.write(
+          encoder.encode(
+            JSON.stringify({
+              type: 'error',
+              data: data.data,
+            }) + '\n',
+          ),
+        );
+        writer.close();
+        disconnect();
+      }
+    });
+
+    req.signal.addEventListener('abort', () => {
+      disconnect();
+      writer.close();
+    });
+
+    return new Response(responseStream.readable, {
+      headers: {
+        'Content-Type': 'text/event-stream',
+        Connection: 'keep-alive',
+        'Cache-Control': 'no-cache, no-transform',
+      },
+    });
+  } catch (err) {
+    console.error('Error in reconnecting to session stream: ', err);
+    return Response.json(
+      { message: 'An error has occurred.' },
+      { status: 500 },
+    );
+  }
+};