use pyo3::ffi::*;
use std::sync::Once;

pub static mut TRUE: *mut pyo3::ffi::PyObject = 0 as *mut pyo3::ffi::PyObject;

pub static mut STR_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut INT_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut BOOL_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut NONE_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut FLOAT_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut LIST_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;
pub static mut DICT_TYPE: *mut PyTypeObject = 0 as *mut PyTypeObject;

static INIT: Once = Once::new();

/// Set empty type object pointers with their actual values.
/// We need these Python-side type objects for direct comparison during conversion to serde types
/// NOTE. This function should be called before any serialization logic
pub fn init() {
    INIT.call_once(|| unsafe {
        TRUE = Py_True();
        STR_TYPE = Py_TYPE(PyUnicode_New(0, 255));
        DICT_TYPE = Py_TYPE(PyDict_New());
        LIST_TYPE = Py_TYPE(PyList_New(0 as Py_ssize_t));
        NONE_TYPE = Py_TYPE(Py_None());
        BOOL_TYPE = Py_TYPE(TRUE);
        INT_TYPE = Py_TYPE(PyLong_FromLongLong(0));
        FLOAT_TYPE = Py_TYPE(PyFloat_FromDouble(0.0));
    });
}