import { createRedisNamedEventResponse } from "@/lib/events/redis-stream";
import { getCommentTarget, getCommentViewer, requireCommentAdmin } from "@/lib/comments/repository";
import { errorResponse, HttpError } from "@/lib/security/http";
import { limitRequest, trustedClientAddress } from "@/lib/security/rate-limit";

export async function GET(request: Request) {
  try {
    await limitRequest("stream-open", trustedClientAddress(request.headers), 60);
    const query = new URL(request.url).searchParams;
    const viewer = await getCommentViewer();
    let topic: string;
    if (query.get("scope") === "admin") {
      requireCommentAdmin(viewer);
      topic = "comments:admin";
    } else {
      const target = query.get("target");
      if (!target) throw new HttpError(400, "target-required");
      const destination = await getCommentTarget(target, viewer);
      topic = `comments:${destination.target}`;
    }
    // Events contain no comment text, images, or author information.
    // Every refresh rechecks current guide visibility and viewer permissions.
    return await createRedisNamedEventResponse(topic, "changed", request.signal);
  } catch (cause) { return errorResponse(cause); }
}