use core::ffi::c_int;
use lunka::prelude::*;

unsafe extern "C" fn l_hello(l: *mut LuaState) -> c_int {
	// SAFETY: Caller ensures `l` is valid.
	let lua = unsafe { LuaThread::from_ptr(l) };

	// SAFETY: An error being raised will not skip any important pieces of code.
	let n = unsafe { lua.check_number(1) };

	// SAFETY: Ditto.
	unsafe { lua.push_string("Hello, world!") };
	lua.push_number(n * core::f64::consts::PI as LuaNumber);

	2
}

const LIBRARY: LuaLibrary<1> = lua_library! {
	hello: l_hello
};

#[export_name = "luaopen_hello"]
unsafe extern "C" fn luaopen_hello(l: *mut LuaState) -> c_int {
	// SAFETY: Caller ensures `l` is valid.
	let lua = unsafe { LuaThread::from_ptr(l) };

	// SAFETY: An error being raised will not skip any important pieces of code.
	unsafe { lua.new_lib(&LIBRARY) };

	1
}