#include "nif_utils.h"
#include "erltls_nif.h"
#include "macros.h"

#include <string.h>

// disable for the moment as time benchmarks shows performances decreased with 20 - 30 %
// will enable after more investigations

#if defined(USE_CONSUME_TIMESLICE)
// this should correspond to the similar define in erltls_nif.erl
#define MAX_BYTES_TO_NIF 40960
#endif

ERL_NIF_TERM make_atom(ErlNifEnv* env, const char* name)
{
    ERL_NIF_TERM ret;

    if(enif_make_existing_atom(env, name, &ret, ERL_NIF_LATIN1))
        return ret;

    return enif_make_atom(env, name);
}

ERL_NIF_TERM make_binary(ErlNifEnv* env, const uint8_t* buff, size_t length)
{
    ERL_NIF_TERM term;
    uint8_t *destination_buffer = enif_make_new_binary(env, length, &term);
    memcpy(destination_buffer, buff, length);
    return term;
}

ERL_NIF_TERM make_binary(ErlNifEnv* env, const std::string& string)
{
    return make_binary(env, reinterpret_cast<const uint8_t*>(string.c_str()), string.length());
}

ERL_NIF_TERM make_error(ErlNifEnv* env, const char* error)
{
    return make_error(env, make_binary(env, reinterpret_cast<const uint8_t*>(error), strlen(error)));
}

ERL_NIF_TERM make_error(ErlNifEnv* env, ERL_NIF_TERM term)
{
    return enif_make_tuple2(env, ATOMS.atomError, term);
}

ERL_NIF_TERM make_bad_options(ErlNifEnv* env, ERL_NIF_TERM term)
{
    return make_error(env, enif_make_tuple(env, 2, ATOMS.atomOptions, term));
}

ERL_NIF_TERM make_badarg(ErlNifEnv* env)
{
    return enif_make_tuple2(env, ATOMS.atomError, ATOMS.atomBadArg);
}

ERL_NIF_TERM make_ok_result(ErlNifEnv* env, ERL_NIF_TERM term)
{
    return enif_make_tuple(env, 2, ATOMS.atomOk, term);
}

void consume_timeslice(ErlNifEnv *env, size_t bytes)
{
#if defined(USE_CONSUME_TIMESLICE)
    int cost = static_cast<int>((bytes * 100) / MAX_BYTES_TO_NIF);

    if(cost)
        enif_consume_timeslice(env, cost > 100 ? 100 : cost);
#else
    UNUSED(env);
    UNUSED(bytes);
#endif
}

bool get_binary(ErlNifEnv* env, ERL_NIF_TERM term, ErlNifBinary* bin)
{
    if(enif_is_binary(env, term))
        return enif_inspect_binary(env, term, bin);

    return enif_inspect_iolist_as_binary(env, term, bin);
}

bool get_string(ErlNifEnv *env, ERL_NIF_TERM term, std::string* var)
{
    ErlNifBinary bin;

    if(get_binary(env, term, &bin))
    {
        *var = std::string(reinterpret_cast<const char*>(bin.data), bin.size);
        return true;
    }

    return false;
}

bool get_boolean(ERL_NIF_TERM term, bool* val)
{
    if(enif_is_identical(term, ATOMS.atomTrue))
    {
        *val = true;
        return true;
    }

    if(enif_is_identical(term, ATOMS.atomFalse))
    {
        *val = false;
        return true;
    }

    return false;
}