/**
 * Strip TypeScript from a generated browser module.
 *
 * A client function's body is emitted verbatim, so anything TypeScript-only
 * inside one -- an annotated local, an `as` cast, a local interface -- reaches
 * the browser module as TypeScript source. Codegen removes the types from the
 * function's *signature*, which is what made this easy to miss: the emitted
 * module looked transpiled, and only bodies carried types through.
 *
 * The artifact is written as `.mjs` and read back as plain JavaScript, so the
 * failure surfaced as a syntax error pointing at generated code rather than at
 * the `.wrn` line responsible.
 */

let transpiler: { transformSync(code: string): string } | null = null;

export function stripBrowserTypes(code: string): string {
  const bun = (
    globalThis as unknown as {
      Bun?: { Transpiler: new (options: unknown) => { transformSync(code: string): string } };
    }
  ).Bun;

  if (!bun?.Transpiler) {
    throw new Error(
      "WRN-CLIENT-TS: emitting a browser module needs the Bun transpiler to remove TypeScript from client function bodies.",
    );
  }

  transpiler ??= new bun.Transpiler({ loader: "ts", target: "browser" });

  return transpiler.transformSync(code);
}