use std::ffi::c_void;
use std::rc::Rc;

pub use callback_info::*;
pub use ctor::ctor;
pub use env::*;
pub use iterator::Generator;
pub use js_values::*;
pub use module_register::*;

use super::sys;
use crate::{JsError, Result, Status};

mod callback_info;
mod env;
mod error;
pub mod iterator;
mod js_values;
mod module_register;

pub trait ObjectFinalize: Sized {
  #[allow(unused)]
  fn finalize(self, env: Env) -> Result<()> {
    Ok(())
  }
}

/// # Safety
///
/// called when node wrapper objects destroyed
#[doc(hidden)]
pub unsafe extern "C" fn raw_finalize_unchecked<T: ObjectFinalize>(
  env: sys::napi_env,
  finalize_data: *mut c_void,
  _finalize_hint: *mut c_void,
) {
  let data: Box<T> = unsafe { Box::from_raw(finalize_data.cast()) };
  if let Err(err) = data.finalize(Env::from_raw(env)) {
    let e: JsError = err.into();
    unsafe { e.throw_into(env) };
    return;
  }
  if let Some((_, ref_val, finalize_callbacks_ptr)) =
    REFERENCE_MAP.with(|reference_map| reference_map.borrow_mut().remove(&finalize_data))
  {
    let finalize_callbacks_rc = unsafe { Rc::from_raw(finalize_callbacks_ptr) };

    #[cfg(all(debug_assertions, not(target_family = "wasm")))]
    {
      let rc_strong_count = Rc::strong_count(&finalize_callbacks_rc);
      // If `Rc` strong count is 2, it means the finalize of referenced `Object` is called before the `fn drop` of the `Reference`
      // It always happened on exiting process
      // In general, the `fn drop` would happen first
      assert!(
        rc_strong_count == 1 || rc_strong_count == 2,
        "Rc strong count is: {}, it should be 1 or 2",
        rc_strong_count
      );
    }
    let finalize = unsafe { Box::from_raw(finalize_callbacks_rc.get()) };
    finalize();
    let delete_reference_status = unsafe { sys::napi_delete_reference(env, ref_val) };
    debug_assert!(
      delete_reference_status == sys::Status::napi_ok,
      "Delete reference in finalize callback failed {}",
      Status::from(delete_reference_status)
    );
  }
}

/// # Safety
///
/// called when node buffer is ready for gc
#[doc(hidden)]
pub unsafe extern "C" fn drop_buffer(
  _env: sys::napi_env,
  #[allow(unused)] finalize_data: *mut c_void,
  finalize_hint: *mut c_void,
) {
  #[cfg(all(debug_assertions, not(windows)))]
  {
    js_values::BUFFER_DATA.with(|buffer_data| {
      let mut buffer = buffer_data.lock().expect("Unlock Buffer data failed");
      buffer.remove(&(finalize_data as *mut u8));
    });
  }
  unsafe {
    drop(Box::from_raw(finalize_hint as *mut Buffer));
  }
}