1use editor::Editor;
 2use gpui::{
 3    elements::*, CursorStyle, Entity, MouseButton, RenderContext, Subscription, View, ViewContext,
 4    ViewHandle,
 5};
 6use settings::Settings;
 7use std::sync::Arc;
 8use workspace::{item::ItemHandle, StatusItemView};
 9
10pub struct ActiveBufferLanguage {
11    active_language: Option<Arc<str>>,
12    _observe_active_editor: Option<Subscription>,
13}
14
15impl Default for ActiveBufferLanguage {
16    fn default() -> Self {
17        Self::new()
18    }
19}
20
21impl ActiveBufferLanguage {
22    pub fn new() -> Self {
23        Self {
24            active_language: None,
25            _observe_active_editor: None,
26        }
27    }
28
29    fn update_language(&mut self, editor: ViewHandle<Editor>, cx: &mut ViewContext<Self>) {
30        let editor = editor.read(cx);
31        self.active_language.take();
32        if let Some((_, buffer, _)) = editor.active_excerpt(cx) {
33            if let Some(language) = buffer.read(cx).language() {
34                self.active_language = Some(language.name());
35            }
36        }
37
38        cx.notify();
39    }
40}
41
42impl Entity for ActiveBufferLanguage {
43    type Event = ();
44}
45
46impl View for ActiveBufferLanguage {
47    fn ui_name() -> &'static str {
48        "ActiveBufferLanguage"
49    }
50
51    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
52        if let Some(active_language) = self.active_language.as_ref() {
53            MouseEventHandler::<Self>::new(0, cx, |state, cx| {
54                let theme = &cx.global::<Settings>().theme.workspace.status_bar;
55                let style = theme.active_language.style_for(state, false);
56                Label::new(active_language.to_string(), style.text.clone())
57                    .contained()
58                    .with_style(style.container)
59                    .boxed()
60            })
61            .with_cursor_style(CursorStyle::PointingHand)
62            .on_click(MouseButton::Left, |_, cx| cx.dispatch_action(crate::Toggle))
63            .boxed()
64        } else {
65            Empty::new().boxed()
66        }
67    }
68}
69
70impl StatusItemView for ActiveBufferLanguage {
71    fn set_active_pane_item(
72        &mut self,
73        active_pane_item: Option<&dyn ItemHandle>,
74        cx: &mut ViewContext<Self>,
75    ) {
76        if let Some(editor) = active_pane_item.and_then(|item| item.act_as::<Editor>(cx)) {
77            self._observe_active_editor = Some(cx.observe(&editor, Self::update_language));
78            self.update_language(editor, cx);
79        } else {
80            self.active_language = None;
81            self._observe_active_editor = None;
82        }
83
84        cx.notify();
85    }
86}