1use gpui::{div, Context, Element, Entity, Render, Subscription, WeakEntity, Window};
  2use itertools::Itertools;
  3use workspace::{item::ItemHandle, ui::prelude::*, StatusItemView};
  4
  5use crate::{Vim, VimEvent, VimGlobals};
  6
  7/// The ModeIndicator displays the current mode in the status bar.
  8pub struct ModeIndicator {
  9    vim: Option<WeakEntity<Vim>>,
 10    pending_keys: Option<String>,
 11    vim_subscription: Option<Subscription>,
 12}
 13
 14impl ModeIndicator {
 15    /// Construct a new mode indicator in this window.
 16    pub fn new(window: &mut Window, cx: &mut Context<Self>) -> Self {
 17        cx.observe_pending_input(window, |this: &mut Self, window, cx| {
 18            this.update_pending_keys(window);
 19            cx.notify();
 20        })
 21        .detach();
 22
 23        let handle = cx.entity().clone();
 24        let window_handle = window.window_handle();
 25        cx.observe_new::<Vim>(move |_, window, cx| {
 26            let Some(window) = window else {
 27                return;
 28            };
 29            if window.window_handle() != window_handle {
 30                return;
 31            }
 32            let vim = cx.entity().clone();
 33            handle.update(cx, |_, cx| {
 34                cx.subscribe(&vim, |mode_indicator, vim, event, cx| match event {
 35                    VimEvent::Focused => {
 36                        mode_indicator.vim_subscription =
 37                            Some(cx.observe(&vim, |_, _, cx| cx.notify()));
 38                        mode_indicator.vim = Some(vim.downgrade());
 39                    }
 40                })
 41                .detach()
 42            })
 43        })
 44        .detach();
 45
 46        Self {
 47            vim: None,
 48            pending_keys: None,
 49            vim_subscription: None,
 50        }
 51    }
 52
 53    fn update_pending_keys(&mut self, window: &mut Window) {
 54        self.pending_keys = window.pending_input_keystrokes().map(|keystrokes| {
 55            keystrokes
 56                .iter()
 57                .map(|keystroke| format!("{}", keystroke))
 58                .join(" ")
 59        });
 60    }
 61
 62    fn vim(&self) -> Option<Entity<Vim>> {
 63        self.vim.as_ref().and_then(|vim| vim.upgrade())
 64    }
 65
 66    fn current_operators_description(&self, vim: Entity<Vim>, cx: &mut Context<Self>) -> String {
 67        let recording = Vim::globals(cx)
 68            .recording_register
 69            .map(|reg| format!("recording @{reg} "))
 70            .into_iter();
 71
 72        let vim = vim.read(cx);
 73        recording
 74            .chain(
 75                cx.global::<VimGlobals>()
 76                    .pre_count
 77                    .map(|count| format!("{}", count)),
 78            )
 79            .chain(vim.selected_register.map(|reg| format!("\"{reg}")))
 80            .chain(
 81                vim.operator_stack
 82                    .iter()
 83                    .map(|item| item.status().to_string()),
 84            )
 85            .chain(
 86                cx.global::<VimGlobals>()
 87                    .post_count
 88                    .map(|count| format!("{}", count)),
 89            )
 90            .collect::<Vec<_>>()
 91            .join("")
 92    }
 93}
 94
 95impl Render for ModeIndicator {
 96    fn render(&mut self, _: &mut Window, cx: &mut Context<Self>) -> impl IntoElement {
 97        let vim = self.vim();
 98        let Some(vim) = vim else {
 99            return div().into_any();
100        };
101
102        let vim_readable = vim.read(cx);
103        let label = if let Some(label) = vim_readable.status_label.clone() {
104            label
105        } else {
106            let mode = if vim_readable.temp_mode {
107                format!("(insert) {}", vim_readable.mode)
108            } else {
109                vim_readable.mode.to_string()
110            };
111
112            let current_operators_description = self.current_operators_description(vim.clone(), cx);
113            let pending = self
114                .pending_keys
115                .as_ref()
116                .unwrap_or(&current_operators_description);
117            format!("{} -- {} --", pending, mode).into()
118        };
119
120        Label::new(label)
121            .size(LabelSize::Small)
122            .line_height_style(LineHeightStyle::UiLabel)
123            .into_any_element()
124    }
125}
126
127impl StatusItemView for ModeIndicator {
128    fn set_active_pane_item(
129        &mut self,
130        _active_pane_item: Option<&dyn ItemHandle>,
131        _window: &mut Window,
132        _cx: &mut Context<Self>,
133    ) {
134    }
135}