use std::cell::RefCell;
use std::collections::HashMap;
use std::hash::Hash;
use std::rc::{Rc, Weak};
use crate::langtype::Type;
use crate::object_tree::{Element, ElementRc};
#[derive(Clone)]
pub struct NamedReference(Rc<NamedReferenceInner>);
pub fn pretty_print_element_ref(
f: &mut dyn std::fmt::Write,
element: &Weak<RefCell<Element>>,
) -> std::fmt::Result {
match element.upgrade() {
Some(e) => match e.try_borrow() {
Ok(el) => write!(f, "{}", el.id),
Err(_) => write!(f, "<borrowed>"),
},
None => write!(f, "<null>"),
}
}
impl std::fmt::Debug for NamedReference {
fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
pretty_print_element_ref(f, &self.0.element)?;
write!(f, ".{}", self.0.name)
}
}
impl NamedReference {
pub fn new(element: &ElementRc, name: &str) -> Self {
Self(NamedReferenceInner::from_name(element, name))
}
pub fn name(&self) -> &str {
&self.0.name
}
pub fn element(&self) -> ElementRc {
self.0.element.upgrade().unwrap()
}
pub fn ty(&self) -> Type {
self.element().borrow().lookup_property(self.name()).property_type
}
}
impl Eq for NamedReference {}
impl PartialEq for NamedReference {
fn eq(&self, other: &Self) -> bool {
Rc::ptr_eq(&self.0, &other.0)
}
}
impl Hash for NamedReference {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
Rc::as_ptr(&self.0).hash(state);
}
}
pub struct NamedReferenceInner {
pub element: Weak<RefCell<Element>>,
pub name: String,
}
impl NamedReferenceInner {
fn check_invariant(&self) {
debug_assert!(std::ptr::eq(
self as *const Self,
Rc::as_ptr(
&self.element.upgrade().unwrap().borrow().named_references.0.borrow()[&self.name]
)
))
}
pub fn from_name(element: &ElementRc, name: &str) -> Rc<Self> {
let result = element
.borrow()
.named_references
.0
.borrow_mut()
.entry(name.to_owned())
.or_insert_with_key(|name| {
Rc::new(Self { element: Rc::downgrade(element), name: name.clone() })
})
.clone();
result.check_invariant();
result
}
}
#[derive(Default)]
pub struct NamedReferenceContainer(RefCell<HashMap<String, Rc<NamedReferenceInner>>>);