#include <node_api.h>
#include "../common.h"
#include <stdlib.h>

static int test_value = 1;
static int finalize_count = 0;
static napi_ref test_reference = NULL;

napi_value GetFinalizeCount(napi_env env, napi_callback_info info) {
  napi_value result;
  NAPI_CALL(env, napi_create_int32(env, finalize_count, &result));
  return result;
}

void FinalizeExternal(napi_env env, void* data, void* hint) {
  free(data);
  finalize_count++;
}

napi_value CreateExternal(napi_env env, napi_callback_info info) {
  int* data = &test_value;

  napi_value result;
  NAPI_CALL(env,
      napi_create_external(env,
                           data,
                           NULL, /* finalize_cb */
                           NULL, /* finalize_hint */
                           &result));

  finalize_count = 0;
  return result;
}

napi_value CreateExternalWithFinalize(napi_env env, napi_callback_info info) {
  int* data = malloc(sizeof(int));
  *data = test_value;

  napi_value result;
  NAPI_CALL(env,
      napi_create_external(env,
                           data,
                           FinalizeExternal,
                           NULL, /* finalize_hint */
                           &result));

  finalize_count = 0;
  return result;
}

napi_value CheckExternal(napi_env env, napi_callback_info info) {
  size_t argc = 1;
  napi_value arg;
  NAPI_CALL(env, napi_get_cb_info(env, info, &argc, &arg, NULL, NULL));

  NAPI_ASSERT(env, argc == 1, "Expected one argument.");

  napi_valuetype argtype;
  NAPI_CALL(env, napi_typeof(env, arg, &argtype));

  NAPI_ASSERT(env, argtype == napi_external, "Expected an external value.");

  void* data;
  NAPI_CALL(env, napi_get_value_external(env, arg, &data));

  NAPI_ASSERT(env, data != NULL && *(int*)data == test_value,
      "An external data value of 1 was expected.");

  return NULL;
}

napi_value CreateReference(napi_env env, napi_callback_info info) {
  NAPI_ASSERT(env, test_reference == NULL,
      "The test allows only one reference at a time.");

  size_t argc = 2;
  napi_value args[2];
  NAPI_CALL(env, napi_get_cb_info(env, info, &argc, args, NULL, NULL));
  NAPI_ASSERT(env, argc == 2, "Expected two arguments.");

  uint32_t initial_refcount;
  NAPI_CALL(env, napi_get_value_uint32(env, args[1], &initial_refcount));

  NAPI_CALL(env,
      napi_create_reference(env, args[0], initial_refcount, &test_reference));

  NAPI_ASSERT(env, test_reference != NULL,
      "A reference should have been created.");

  return NULL;
}

napi_value DeleteReference(napi_env env, napi_callback_info info) {
  NAPI_ASSERT(env, test_reference != NULL,
      "A reference must have been created.");

  NAPI_CALL(env, napi_delete_reference(env, test_reference));
  test_reference = NULL;
  return NULL;
}

napi_value IncrementRefcount(napi_env env, napi_callback_info info) {
  NAPI_ASSERT(env, test_reference != NULL,
      "A reference must have been created.");

  uint32_t refcount;
  NAPI_CALL(env, napi_reference_ref(env, test_reference, &refcount));

  napi_value result;
  NAPI_CALL(env, napi_create_uint32(env, refcount, &result));
  return result;
}

napi_value DecrementRefcount(napi_env env, napi_callback_info info) {
  NAPI_ASSERT(env, test_reference != NULL,
      "A reference must have been created.");

  uint32_t refcount;
  NAPI_CALL(env, napi_reference_unref(env, test_reference, &refcount));

  napi_value result;
  NAPI_CALL(env, napi_create_uint32(env, refcount, &result));
  return result;
}

napi_value GetReferenceValue(napi_env env, napi_callback_info info) {
  NAPI_ASSERT(env, test_reference != NULL,
      "A reference must have been created.");

  napi_value result;
  NAPI_CALL(env, napi_get_reference_value(env, test_reference, &result));
  return result;
}

napi_value Init(napi_env env, napi_value exports) {
  napi_property_descriptor descriptors[] = {
    DECLARE_NAPI_GETTER("finalizeCount", GetFinalizeCount),
    DECLARE_NAPI_PROPERTY("createExternal", CreateExternal),
    DECLARE_NAPI_PROPERTY("createExternalWithFinalize",
        CreateExternalWithFinalize),
    DECLARE_NAPI_PROPERTY("checkExternal", CheckExternal),
    DECLARE_NAPI_PROPERTY("createReference", CreateReference),
    DECLARE_NAPI_PROPERTY("deleteReference", DeleteReference),
    DECLARE_NAPI_PROPERTY("incrementRefcount", IncrementRefcount),
    DECLARE_NAPI_PROPERTY("decrementRefcount", DecrementRefcount),
    DECLARE_NAPI_GETTER("referenceValue", GetReferenceValue),
  };

  NAPI_CALL(env, napi_define_properties(
      env, exports, sizeof(descriptors) / sizeof(*descriptors), descriptors));

  return exports;
}

NAPI_MODULE(NODE_GYP_MODULE_NAME, Init)