1use gpui::{AppContext, Global, Subscription, ViewContext};
 2
 3#[derive(Default)]
 4struct FeatureFlags {
 5    flags: Vec<String>,
 6    staff: bool,
 7}
 8
 9impl FeatureFlags {
10    fn has_flag(&self, flag: &str) -> bool {
11        self.staff || self.flags.iter().any(|f| f.as_str() == flag)
12    }
13}
14
15impl Global for FeatureFlags {}
16
17pub trait FeatureFlag {
18    const NAME: &'static str;
19}
20
21pub trait FeatureFlagViewExt<V: 'static> {
22    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
23    where
24        F: Fn(bool, &mut V, &mut ViewContext<V>) + Send + Sync + 'static;
25}
26
27impl<V> FeatureFlagViewExt<V> for ViewContext<'_, V>
28where
29    V: 'static,
30{
31    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
32    where
33        F: Fn(bool, &mut V, &mut ViewContext<V>) + 'static,
34    {
35        self.observe_global::<FeatureFlags>(move |v, cx| {
36            let feature_flags = cx.global::<FeatureFlags>();
37            callback(feature_flags.has_flag(<T as FeatureFlag>::NAME), v, cx);
38        })
39    }
40}
41
42pub trait FeatureFlagAppExt {
43    fn update_flags(&mut self, staff: bool, flags: Vec<String>);
44    fn set_staff(&mut self, staff: bool);
45    fn has_flag<T: FeatureFlag>(&self) -> bool;
46    fn is_staff(&self) -> bool;
47}
48
49impl FeatureFlagAppExt for AppContext {
50    fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
51        let feature_flags = self.default_global::<FeatureFlags>();
52        feature_flags.staff = staff;
53        feature_flags.flags = flags;
54    }
55
56    fn set_staff(&mut self, staff: bool) {
57        let feature_flags = self.default_global::<FeatureFlags>();
58        feature_flags.staff = staff;
59    }
60
61    fn has_flag<T: FeatureFlag>(&self) -> bool {
62        self.try_global::<FeatureFlags>()
63            .map(|flags| flags.has_flag(T::NAME))
64            .unwrap_or(false)
65    }
66
67    fn is_staff(&self) -> bool {
68        self.try_global::<FeatureFlags>()
69            .map(|flags| flags.staff)
70            .unwrap_or(false)
71    }
72}