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use std::sync::Arc;

use crate::{
    dom_adapter::NodeKey,
    geometry::Size2D,
    node::Node,
    prelude::{
        Area,
        SendAnyMap,
    },
};

pub trait LayoutMeasurer<Key: NodeKey> {
    fn measure(
        &mut self,
        node_id: Key,
        node: &Node,
        size: &Size2D,
    ) -> Option<(Size2D, Arc<SendAnyMap>)>;

    fn should_measure_inner_children(&mut self, node_id: Key) -> bool;

    fn notify_layout_references(&self, _node_id: Key, _area: Area, _inner_sizes: Size2D) {}
}

// No-op measurer, use it when you don't need one.
pub struct NoopMeasurer;

impl LayoutMeasurer<usize> for NoopMeasurer {
    fn measure(
        &mut self,
        _node_id: usize,
        _node: &Node,
        _size: &Size2D,
    ) -> Option<(Size2D, Arc<SendAnyMap>)> {
        None
    }

    fn should_measure_inner_children(&mut self, _node_id: usize) -> bool {
        false
    }
}