1use gpui::{AppContext, 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().find(|f| f.as_str() == flag).is_some()
12    }
13}
14
15pub trait FeatureFlag {
16    const NAME: &'static str;
17}
18
19pub enum ChannelsAlpha {}
20
21impl FeatureFlag for ChannelsAlpha {
22    const NAME: &'static str = "channels_alpha";
23}
24
25pub trait FeatureFlagViewExt<V: 'static> {
26    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
27    where
28        F: Fn(bool, &mut V, &mut ViewContext<V>) + 'static;
29}
30
31impl<V: 'static> FeatureFlagViewExt<V> for ViewContext<'_, '_, V> {
32    fn observe_flag<T: FeatureFlag, F>(&mut self, callback: F) -> Subscription
33    where
34        F: Fn(bool, &mut V, &mut ViewContext<V>) + 'static,
35    {
36        self.observe_global::<FeatureFlags, _>(move |v, cx| {
37            let feature_flags = cx.global::<FeatureFlags>();
38            callback(feature_flags.has_flag(<T as FeatureFlag>::NAME), v, cx);
39        })
40    }
41}
42
43pub trait FeatureFlagAppExt {
44    fn update_flags(&mut self, staff: bool, flags: Vec<String>);
45    fn set_staff(&mut self, staff: bool);
46    fn has_flag<T: FeatureFlag>(&self) -> bool;
47    fn is_staff(&self) -> bool;
48}
49
50impl FeatureFlagAppExt for AppContext {
51    fn update_flags(&mut self, staff: bool, flags: Vec<String>) {
52        self.update_default_global::<FeatureFlags, _, _>(|feature_flags, _| {
53            feature_flags.staff = staff;
54            feature_flags.flags = flags;
55        })
56    }
57
58    fn set_staff(&mut self, staff: bool) {
59        self.update_default_global::<FeatureFlags, _, _>(|feature_flags, _| {
60            feature_flags.staff = staff;
61        })
62    }
63
64    fn has_flag<T: FeatureFlag>(&self) -> bool {
65        if self.has_global::<FeatureFlags>() {
66            self.global::<FeatureFlags>().has_flag(T::NAME)
67        } else {
68            false
69        }
70    }
71
72    fn is_staff(&self) -> bool {
73        if self.has_global::<FeatureFlags>() {
74            return self.global::<FeatureFlags>().staff;
75        } else {
76            false
77        }
78    }
79}