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use crate::sendwrap_fn;
use crate::utils::Pausable;
use cfg_if::cfg_if;
use default_struct_builder::DefaultBuilder;
use leptos::prelude::*;
use std::cell::{Cell, RefCell};
use std::rc::Rc;
/// Call function on every requestAnimationFrame.
/// With controls of pausing and resuming.
///
/// ## Demo
///
/// [Link to Demo](https://github.com/Synphonyte/leptos-use/tree/main/examples/use_raf_fn)
///
/// ## Usage
///
/// ```
/// # use leptos::prelude::*;
/// # use leptos_use::use_raf_fn;
/// use leptos_use::utils::Pausable;
/// #
/// # #[component]
/// # fn Demo() -> impl IntoView {
/// let (count, set_count) = signal(0);
///
/// let Pausable { pause, resume, is_active } = use_raf_fn(move |_| {
/// set_count.update(|count| *count += 1);
/// });
///
/// view! { <div>Count: { count }</div> }
/// }
/// ```
///
/// You can use `use_raf_fn_with_options` and set `immediate` to `false`. In that case
/// you have to call `resume()` before the `callback` is executed.
///
/// ## SendWrapped Return
///
/// The returned closures `pause` and `resume` are sendwrapped functions. They can
/// only be called from the same thread that called `use_interval_fn`.
///
/// ## Server-Side Rendering
///
/// On the server this does basically nothing. The provided closure will never be called.
pub fn use_raf_fn(
callback: impl Fn(UseRafFnCallbackArgs) + 'static,
) -> Pausable<impl Fn() + Clone + Send + Sync, impl Fn() + Clone + Send + Sync> {
use_raf_fn_with_options(callback, UseRafFnOptions::default())
}
/// Version of [`use_raf_fn`] that takes a `UseRafFnOptions`. See [`use_raf_fn`] for how to use.
pub fn use_raf_fn_with_options(
callback: impl Fn(UseRafFnCallbackArgs) + 'static,
options: UseRafFnOptions,
) -> Pausable<impl Fn() + Clone + Send + Sync, impl Fn() + Clone + Send + Sync> {
let UseRafFnOptions { immediate } = options;
let raf_handle = Rc::new(Cell::new(None::<i32>));
let (is_active, set_active) = signal(false);
let loop_ref = Rc::new(RefCell::new(Box::new(|_: f64| {}) as Box<dyn Fn(f64)>));
let request_next_frame = {
cfg_if! { if #[cfg(feature = "ssr")] {
move || ()
} else {
use wasm_bindgen::JsCast;
use wasm_bindgen::closure::Closure;
let loop_ref = Rc::clone(&loop_ref);
let raf_handle = Rc::clone(&raf_handle);
move || {
let loop_ref = Rc::clone(&loop_ref);
raf_handle.set(
window()
.request_animation_frame(
Closure::once_into_js(move |timestamp: f64| {
loop_ref.borrow()(timestamp);
})
.as_ref()
.unchecked_ref(),
)
.ok(),
);
}
}}
};
let loop_fn = {
#[allow(clippy::clone_on_copy)]
let request_next_frame = request_next_frame.clone();
let previous_frame_timestamp = Cell::new(0.0_f64);
move |timestamp: f64| {
if !is_active.try_get_untracked().unwrap_or_default() {
return;
}
let prev_timestamp = previous_frame_timestamp.get();
let delta = if prev_timestamp > 0.0 {
timestamp - prev_timestamp
} else {
0.0
};
#[cfg(debug_assertions)]
let zone = leptos::reactive::diagnostics::SpecialNonReactiveZone::enter();
callback(UseRafFnCallbackArgs { delta, timestamp });
#[cfg(debug_assertions)]
drop(zone);
previous_frame_timestamp.set(timestamp);
request_next_frame();
}
};
let _ = loop_ref.replace(Box::new(loop_fn));
let resume = sendwrap_fn!(move || {
if !is_active.get_untracked() {
set_active.set(true);
request_next_frame();
}
});
let pause = sendwrap_fn!(move || {
set_active.set(false);
let handle = raf_handle.get();
if let Some(handle) = handle {
let _ = window().cancel_animation_frame(handle);
}
raf_handle.set(None);
});
if immediate {
resume();
}
on_cleanup({
let pause = pause.clone();
#[allow(clippy::redundant_closure)]
move || pause()
});
Pausable {
resume,
pause,
is_active: is_active.into(),
}
}
/// Options for [`use_raf_fn_with_options`].
#[derive(DefaultBuilder)]
pub struct UseRafFnOptions {
/// Start the requestAnimationFrame loop immediately on creation. Defaults to `true`.
/// If false, the loop will only start when you call `resume()`.
immediate: bool,
}
impl Default for UseRafFnOptions {
fn default() -> Self {
Self { immediate: true }
}
}
/// Type of the argument for the callback of [`use_raf_fn`].
pub struct UseRafFnCallbackArgs {
/// Time elapsed between this and the last frame.
pub delta: f64,
/// Time elapsed since the creation of the web page. See [MDN Docs](https://developer.mozilla.org/en-US/docs/Web/API/DOMHighResTimeStamp#the_time_origin) Time origin.
pub timestamp: f64,
}