use napi::bindgen_prelude::*;
use napi_derive::napi;

/// module registration is done by the runtime, no need to explicitly do it now.
#[napi]
pub fn fibonacci(n: u32) -> u32 {
  match n {
    1 | 2 => 1,
    _ => fibonacci(n - 1) + fibonacci(n - 2),
  }
}

/// use `Fn`, `FnMut` or `FnOnce` traits to defined JavaScript callbacks
/// the return type of callbacks can only be `Result`.
#[napi]
pub fn get_cwd<T: Fn(String) -> Result<()>>(callback: T) {
  callback(
    std::env::current_dir()
      .unwrap()
      .to_string_lossy()
      .to_string(),
  )
  .unwrap();
}

/// or, define the callback signature in where clause
#[napi]
pub fn test_callback<T>(callback: T) -> Result<()>
where
  T: Fn(String) -> Result<()>,
{
  callback(std::env::current_dir()?.to_string_lossy().to_string())
}

/// async fn, require `async` feature enabled.
/// [dependencies]
/// napi = {version="2", features=["async"]}
#[napi]
pub async fn read_file_async(path: String) -> Result<Buffer> {
  Ok(tokio::fs::read(path).await?.into())
}

[package]
name = "awesome"

[lib]
crate-type = ["cdylib"]

[dependencies]
napi = "3"
napi-derive = "3"

[build-dependencies]
napi-build = "1"

// build.rs
extern crate napi_build;

fn main() {
  napi_build::setup();
}

{
  "package": "awesome-package",
  "devDependencies": {
    "@napi-rs/cli": "^1.0.0"
  },
  "napi": {
    "name": "jarvis" // <----------- Config the name of native addon, or the napi command will use the name of `Cargo.toml` for the binary file name.
  },
  "scripts": {
    "build": "napi build --release",
    "build:debug": "napi build"
  }
}

napi build [--release] ./dll
napi build [--release] ./artifacts

yarn build:test
yarn test