import { createOpenRouter } from "@openrouter/ai-sdk-provider";
import { streamText, UIMessage, convertToModelMessages } from "ai";

export async function POST(req: Request) {
  const { messages }: { messages: UIMessage[] } = await req.json();

  // Initialize OpenRouter with API key from environment
  const openrouter = createOpenRouter({
    apiKey: process.env.OPENROUTER_API_KEY,
  });

  const result = streamText({
    model: openrouter(process.env.OPENROUTER_MODEL || "openai/gpt-5-mini"),
    messages: convertToModelMessages(messages),
  });

  return (
    result as unknown as { toUIMessageStreamResponse: () => Response }
  ).toUIMessageStreamResponse();
}