feat: add extensive test suite

app/api/chat/handler.ts

@@ -0,0 +1,40 @@
+type LiveResponse = { url: string } | "none";
+
+type Fetch = (
+  input: RequestInfo | URL,
+  init?: RequestInit,
+) => Promise<Response>;
+
+export function createChatHandler({ fetch }: { fetch: Fetch }) {
+  return async function GET(request: Request) {
+    const liveUrl = new URL(
+      "https://buzz.sudloh.com/api/live",
+      request.url,
+    ).toString();
+    const response = await fetch(liveUrl, { cache: "no-store" });
+
+    if (!response.ok)
+      return new Response("Failed to get live stream.", { status: 502 });
+
+    const liveInfo: LiveResponse = await response.json();
+    if (liveInfo === "none")
+      return new Response("No live stream found for this channel.", {
+        status: 404,
+      });
+
+    let videoId: string | null = null;
+    try {
+      videoId = new URL(liveInfo.url).searchParams.get("v");
+    } catch {}
+
+    if (!videoId)
+      return new Response("Live stream video id was not found.", {
+        status: 502,
+      });
+
+    return Response.redirect(
+      `https://studio.youtube.com/live_chat?is_popout=1&v=${encodeURIComponent(videoId)}`,
+      307,
+    );
+  };
+}