asteracea 0.0.2

use crate::rhizome::extractable;
use lazy_static::lazy_static;
use lignin_schema::{
	div,
	lignin::{bumpalo::Bump, Attribute, Node},
};
use std::{collections::HashMap, sync::Mutex};

//TODO: This should be default-provided at root, but that requires a stateful implementation (i.e. captures).
//TODO: Reference vdom_provider and kick off a render when a style is added.
extractable! {
	pub abstract trait Styles

	// This would be nicer with 'bump, but that appears to count as generic when using higher kinded types to express it.
	fn add_boxed(&self, key: &str, factory: Box<dyn FnOnce(&'static Bump) -> Node<'static>>);

	fn render<'bump>(&self, bump: &'bump Bump) -> Node<'bump>;
}

impl dyn Styles {
	pub fn add(
		&self,
		key: &str,
		factory: impl for<'bump> FnOnce(&'bump Bump) -> Node<'bump> + 'static,
	) {
		//TODO?: Constrain to style elements.
		self.add_boxed(key, Box::new(factory))
	}
}

pub struct TempImpl {
	bump: &'static Bump,
	styles: Mutex<HashMap<String, Node<'static>>>,
}

impl TempImpl {
	#[must_use]
	pub fn new() -> Self {
		Self {
			bump: Box::leak(Box::default()),
			styles: Mutex::default(),
		}
	}
}

impl Default for TempImpl {
	fn default() -> Self {
		Self::new()
	}
}

lazy_static! {
	static ref ATTRIBUTES: [Attribute<'static>; 1] = [Attribute {
		name: "style",
		value: "display: none;"
	}];
}
impl Styles for TempImpl {
	fn add_boxed(&self, key: &str, factory: Box<dyn FnOnce(&'static Bump) -> Node<'static>>) {
		let mut styles = self.styles.lock().unwrap();
		if !styles.contains_key(key) {
			styles.insert(key.to_owned(), factory(self.bump));
		}
	}

	fn render<'bump>(&self, bump: &'bump Bump) -> Node<'bump> {
		let guard = self.styles.lock().unwrap();
		let children = bump.alloc_slice_fill_iter(guard.values().copied());
		let event_bindings = bump.alloc_with(|| []);
		(bump.alloc_with(move || div(&*ATTRIBUTES, &*children, &*event_bindings))).into()
	}
}