Function POST

src/app/api/chat/route.ts:23–181

(request: Request)

} from "@/lib/model-provider";

export async function POST(request: Request) {
  const body = await request.json();
  const {
    messages,
    modelProvider,
  }: {
    messages: UIMessage[];
    modelProvider?: string;
  } = body;

  // Validate and sanitize model provider
  const provider: ModelProvider =
    modelProvider && isProviderValid(modelProvider) ? modelProvider : "sonnet"; // default fallback

  logger.info("Chat API called", {
    messageCount: messages.length,
    lastMessageRole: messages[messages.length - 1]?.role,
    modelProvider: provider,
  });

  // Parse component context from the last user message if present
  let componentContext = null;
  let processedMessages = messages;

  const lastMessage = messages[messages.length - 1];
  if (lastMessage?.role === "user") {
    const textPart = lastMessage.parts?.find(
      (part: any) => part.type === "text",
    ) as any;
    const textContent = textPart?.text;

    if (textContent) {
      const componentMatch = textContent.match(
        /\[SELECTED COMPONENT\]\n([\s\S]*?)\n\n\[USER MESSAGE\]\n([\s\S]*)/,
      );

      if (componentMatch) {
        try {
          componentContext = JSON.parse(componentMatch[1]);
          const userMessage = componentMatch[2];

          // Replace the last message with the extracted user message
          processedMessages = [
            ...messages.slice(0, -1),
            {
              ...lastMessage,
              parts: [
                {
                  type: "text",
                  text: userMessage,
                },
              ],
            },
          ];

          logger.info("Component context extracted", {
            componentName: componentContext.componentName,
            hasText: !!componentContext.text,