1use smallvec::SmallVec;
 2use std::{
 3    any::{Any, TypeId},
 4    collections::HashMap,
 5};
 6
 7use super::Binding;
 8
 9#[derive(Default)]
10pub struct Keymap {
11    bindings: Vec<Binding>,
12    binding_indices_by_action_type: HashMap<TypeId, SmallVec<[usize; 3]>>,
13}
14
15impl Keymap {
16    pub fn new(bindings: Vec<Binding>) -> Self {
17        let mut binding_indices_by_action_type = HashMap::new();
18        for (ix, binding) in bindings.iter().enumerate() {
19            binding_indices_by_action_type
20                .entry(binding.action().type_id())
21                .or_insert_with(SmallVec::new)
22                .push(ix);
23        }
24
25        Self {
26            binding_indices_by_action_type,
27            bindings,
28        }
29    }
30
31    pub(crate) fn bindings_for_action_type(
32        &self,
33        action_type: TypeId,
34    ) -> impl Iterator<Item = &'_ Binding> {
35        self.binding_indices_by_action_type
36            .get(&action_type)
37            .map(SmallVec::as_slice)
38            .unwrap_or(&[])
39            .iter()
40            .map(|ix| &self.bindings[*ix])
41    }
42
43    pub(crate) fn add_bindings<T: IntoIterator<Item = Binding>>(&mut self, bindings: T) {
44        for binding in bindings {
45            self.binding_indices_by_action_type
46                .entry(binding.action().as_any().type_id())
47                .or_default()
48                .push(self.bindings.len());
49            self.bindings.push(binding);
50        }
51    }
52
53    pub(crate) fn clear(&mut self) {
54        self.bindings.clear();
55        self.binding_indices_by_action_type.clear();
56    }
57
58    pub fn bindings(&self) -> &Vec<Binding> {
59        &self.bindings
60    }
61}