euv-core 0.3.27

use crate::*;

/// Implementation of hook context lifecycle and hook index management.
impl HookContext {
    /// Resets the hook index for a new render cycle.
    ///
    /// Sets the internal hook index back to zero so that subsequent
    /// `use_signal` calls start indexing from the beginning of the hook list.
    pub fn reset_hook_index(&mut self) {
        self.get_inner().borrow_mut().set_hook_index(0);
    }

    /// Notifies the hook context that a match arm is being entered.
    ///
    /// If the arm index has changed, all existing hooks and cleanups
    /// are cleared and re-initialized for the new arm. If the arm
    /// is unchanged, only the hook index is reset.
    ///
    /// # Arguments
    ///
    /// - `usize`: The index of the new match arm.
    pub fn set_arm_changed(&mut self, changed: usize) {
        let cleanups: Vec<Box<dyn FnOnce()>>;
        {
            let mut inner: RefMut<HookContextInner> = self.get_inner().borrow_mut();
            if inner.get_arm_changed() == changed {
                drop(inner);
                self.reset_hook_index();
                return;
            }
            cleanups = take(inner.get_mut_cleanups());
            inner.get_mut_hooks().clear();
            inner.set_arm_changed(changed);
        }
        for cleanup in cleanups {
            cleanup();
        }
        self.reset_hook_index();
    }
}

/// Clones the hook context, sharing the same inner state.
impl Clone for HookContext {
    fn clone(&self) -> Self {
        HookContext::new(self.get_inner().clone())
    }
}

/// Provides a default empty hook context.
impl Default for HookContext {
    fn default() -> Self {
        HookContext::new(Rc::new(RefCell::new(HookContextInner::default())))
    }
}

/// SAFETY: `HookContextCell` is only used in single-threaded WASM contexts.
unsafe impl Sync for HookContextCell {}