// isolator/worker.ts
// No module cache to ensure fresh code for every execution.

const States = Object.freeze({
  SUCCESS: "SUCCESS",
  NOT_A_FUNCTION: "NOT_A_FUNCTION",
  SCRIPT_ERROR: "ERROR",
});

self.onmessage = async (e) => {
  const { code, request, environment, name } = e.data;
  const logs: any[] = [];
  const startTime = performance.now();

  // Temporarily override console.log and console.error to capture logs
  const oldConsoleLog = console.log;
  const oldConsoleError = console.error;
  console.log = (...args) => {
    logs.push(args);
    oldConsoleLog.apply(console, args);
  };
  console.error = (...args) => {
    logs.push(args);
    oldConsoleError.apply(console, args);
  };

  try {
    // Make the environment object and response helpers available globally.
    (self as any).environment = environment;
    (self as any).FUNCTION_NAME = name;
    (self as any).Response = (body = "", headers = {}, status = 200) => ({
      body,
      status,
      headers,
    });
    (self as any).JsonResponse = (body = {}, headers = {}, status = 200) =>
      (self as any).Response(
        JSON.stringify(body),
        { "Content-Type": "application/json", ...headers },
        status
      );
    (self as any).HtmlResponse = (body = "", headers = {}, status = 200) =>
      (self as any).Response(
        body,
        { "Content-Type": "text/html", ...headers },
        status
      );
    (self as any).TextResponse = (body = "", headers = {}, status = 200) =>
      (self as any).Response(
        body,
        { "Content-Type": "text/plain", ...headers },
        status
      );

    // Use a data URL to import the user's code as a fresh ES module on every execution.
    const dataUrl = `data:text/javascript;base64,${btoa(
      unescape(encodeURIComponent(code))
    )}`;
    const userModule = await import(dataUrl);

    if (typeof userModule.default !== "function") {
      throw new Error(
        "Module does not have a default export or the export is not a function."
      );
    }

    const userFn = userModule.default;
    const result = await userFn(request);
    const executionTime = performance.now() - startTime;

    self.postMessage({
      status: States.SUCCESS,
      result,
      logs,
      environment: (self as any).environment, // Return the mutated environment.
      execution_time: executionTime,
    });
  } catch (err) {
    const executionTime = performance.now() - startTime;
    self.postMessage({
      status: States.SCRIPT_ERROR,
      result: {
        name: err.name,
        message: err.message,
        stack: err.stack,
      },
      logs,
      environment,
      execution_time: executionTime,
    });
  } finally {
    // Restore original console functions
    console.log = oldConsoleLog;
    console.error = oldConsoleError;
  }
};