#include "thread-safe-callback.h"

#include <stdexcept>

const char *ThreadSafeCallback::CancelException::what() const throw() { return "ThreadSafeCallback cancelled"; }

ThreadSafeCallback::ThreadSafeCallback(Napi::Function callback)
{
  Napi::Env env = callback.Env();

  if (!callback.IsFunction())
    throw Napi::Error::New(env, "Callback must be a function");

  tsfn = tsfn_t::New(env, std::move(callback), "ThreadSafeCallback callback",
                     0, // unlimited queue
                     1);
}

ThreadSafeCallback::~ThreadSafeCallback() { tsfn.Abort(); }

void ThreadSafeCallback::call(arg_func_t argFunc, cleanup_func_t cleanupFunc)
{
  CallbackData *data = new CallbackData{std::move(argFunc), std::move(cleanupFunc)};
  if (tsfn.BlockingCall(data) != napi_ok)
  {
    delete data;
    throw std::runtime_error("Failed to call JavaScript callback");
  }
}

void ThreadSafeCallback::callbackFunc(Napi::Env env, Napi::Function callback, ContextType *context, CallbackData *data)
{
  // if env is gone, it could mean this cb was destroyed. See issue#176
  if (!data || !env)
    return;

  arg_vector_t args;
  arg_func_t argFunc(std::move(data->argFunc));
  cleanup_func_t cleanup(std::move(data->cleanupFunc));
  delete data;

  try
  {
    argFunc(env, args);
  }
  catch (CancelException &)
  {
    return;
  }

  if (callback)
  {
    callback.Call(args);
  }

  cleanup();
}