Merge pull request #2262 from zed-industries/manual-language-selection

Introduce language selector

crates/language_selector/Cargo.toml

@@ -0,0 +1,21 @@
+[package]
+name = "language_selector"
+version = "0.1.0"
+edition = "2021"
+publish = false
+
+[lib]
+path = "src/language_selector.rs"
+doctest = false
+
+[dependencies]
+editor = { path = "../editor" }
+fuzzy = { path = "../fuzzy" }
+language = { path = "../language" }
+gpui = { path = "../gpui" }
+picker = { path = "../picker" }
+project = { path = "../project" }
+theme = { path = "../theme" }
+settings = { path = "../settings" }
+workspace = { path = "../workspace" }
+anyhow = "1.0"

crates/language_selector/src/language_selector.rs

@@ -0,0 +1,228 @@
+use std::sync::Arc;
+
+use editor::Editor;
+use fuzzy::{match_strings, StringMatch, StringMatchCandidate};
+use gpui::{
+    actions, elements::*, AnyViewHandle, AppContext, Entity, ModelHandle, MouseState,
+    MutableAppContext, RenderContext, View, ViewContext, ViewHandle,
+};
+use language::{Buffer, LanguageRegistry};
+use picker::{Picker, PickerDelegate};
+use project::Project;
+use settings::Settings;
+use workspace::{AppState, Workspace};
+
+actions!(language_selector, [Toggle]);
+
+pub fn init(app_state: Arc<AppState>, cx: &mut MutableAppContext) {
+    Picker::<LanguageSelector>::init(cx);
+    cx.add_action({
+        let language_registry = app_state.languages.clone();
+        move |workspace, _: &Toggle, cx| {
+            LanguageSelector::toggle(workspace, language_registry.clone(), cx)
+        }
+    });
+}
+
+pub enum Event {
+    Dismissed,
+}
+
+pub struct LanguageSelector {
+    buffer: ModelHandle<Buffer>,
+    project: ModelHandle<Project>,
+    language_registry: Arc<LanguageRegistry>,
+    candidates: Vec<StringMatchCandidate>,
+    matches: Vec<StringMatch>,
+    picker: ViewHandle<Picker<Self>>,
+    selected_index: usize,
+}
+
+impl LanguageSelector {
+    fn new(
+        buffer: ModelHandle<Buffer>,
+        project: ModelHandle<Project>,
+        language_registry: Arc<LanguageRegistry>,
+        cx: &mut ViewContext<Self>,
+    ) -> Self {
+        let handle = cx.weak_handle();
+        let picker = cx.add_view(|cx| Picker::new("Select Language...", handle, cx));
+
+        let candidates = language_registry
+            .language_names()
+            .into_iter()
+            .enumerate()
+            .map(|(candidate_id, name)| StringMatchCandidate::new(candidate_id, name))
+            .collect::<Vec<_>>();
+        let mut matches = candidates
+            .iter()
+            .map(|candidate| StringMatch {
+                candidate_id: candidate.id,
+                score: 0.,
+                positions: Default::default(),
+                string: candidate.string.clone(),
+            })
+            .collect::<Vec<_>>();
+        matches.sort_unstable_by(|mat1, mat2| mat1.string.cmp(&mat2.string));
+
+        Self {
+            buffer,
+            project,
+            language_registry,
+            candidates,
+            matches,
+            picker,
+            selected_index: 0,
+        }
+    }
+
+    fn toggle(
+        workspace: &mut Workspace,
+        registry: Arc<LanguageRegistry>,
+        cx: &mut ViewContext<Workspace>,
+    ) {
+        if let Some((_, buffer, _)) = workspace
+            .active_item(cx)
+            .and_then(|active_item| active_item.act_as::<Editor>(cx))
+            .and_then(|editor| editor.read(cx).active_excerpt(cx))
+        {
+            workspace.toggle_modal(cx, |workspace, cx| {
+                let project = workspace.project().clone();
+                let this = cx.add_view(|cx| Self::new(buffer, project, registry, cx));
+                cx.subscribe(&this, Self::on_event).detach();
+                this
+            });
+        }
+    }
+
+    fn on_event(
+        workspace: &mut Workspace,
+        _: ViewHandle<LanguageSelector>,
+        event: &Event,
+        cx: &mut ViewContext<Workspace>,
+    ) {
+        match event {
+            Event::Dismissed => {
+                workspace.dismiss_modal(cx);
+            }
+        }
+    }
+}
+
+impl Entity for LanguageSelector {
+    type Event = Event;
+}
+
+impl View for LanguageSelector {
+    fn ui_name() -> &'static str {
+        "LanguageSelector"
+    }
+
+    fn render(&mut self, cx: &mut RenderContext<Self>) -> ElementBox {
+        ChildView::new(self.picker.clone(), cx).boxed()
+    }
+
+    fn focus_in(&mut self, _: AnyViewHandle, cx: &mut ViewContext<Self>) {
+        if cx.is_self_focused() {
+            cx.focus(&self.picker);
+        }
+    }
+}
+
+impl PickerDelegate for LanguageSelector {
+    fn match_count(&self) -> usize {
+        self.matches.len()
+    }
+
+    fn confirm(&mut self, cx: &mut ViewContext<Self>) {
+        if let Some(mat) = self.matches.get(self.selected_index) {
+            let language_name = &self.candidates[mat.candidate_id].string;
+            let language = self.language_registry.language_for_name(language_name);
+            cx.spawn(|this, mut cx| async move {
+                let language = language.await?;
+                this.update(&mut cx, |this, cx| {
+                    this.project.update(cx, |project, cx| {
+                        project.set_language_for_buffer(&this.buffer, language, cx);
+                    });
+                });
+                anyhow::Ok(())
+            })
+            .detach_and_log_err(cx);
+        }
+
+        cx.emit(Event::Dismissed);
+    }
+
+    fn dismiss(&mut self, cx: &mut ViewContext<Self>) {
+        cx.emit(Event::Dismissed);
+    }
+
+    fn selected_index(&self) -> usize {
+        self.selected_index
+    }
+
+    fn set_selected_index(&mut self, ix: usize, _: &mut ViewContext<Self>) {
+        self.selected_index = ix;
+    }
+
+    fn update_matches(&mut self, query: String, cx: &mut ViewContext<Self>) -> gpui::Task<()> {
+        let background = cx.background().clone();
+        let candidates = self.candidates.clone();
+        cx.spawn(|this, mut cx| async move {
+            let matches = if query.is_empty() {
+                candidates
+                    .into_iter()
+                    .enumerate()
+                    .map(|(index, candidate)| StringMatch {
+                        candidate_id: index,
+                        string: candidate.string,
+                        positions: Vec::new(),
+                        score: 0.0,
+                    })
+                    .collect()
+            } else {
+                match_strings(
+                    &candidates,
+                    &query,
+                    false,
+                    100,
+                    &Default::default(),
+                    background,
+                )
+                .await
+            };
+
+            this.update(&mut cx, |this, cx| {
+                this.matches = matches;
+                this.selected_index = this
+                    .selected_index
+                    .min(this.matches.len().saturating_sub(1));
+                cx.notify();
+            });
+        })
+    }
+
+    fn render_match(
+        &self,
+        ix: usize,
+        mouse_state: &mut MouseState,
+        selected: bool,
+        cx: &AppContext,
+    ) -> ElementBox {
+        let settings = cx.global::<Settings>();
+        let theme = &settings.theme;
+        let mat = &self.matches[ix];
+        let style = theme.picker.item.style_for(mouse_state, selected);
+        let buffer_language_name = self.buffer.read(cx).language().map(|l| l.name());
+        let mut label = mat.string.clone();
+        if buffer_language_name.as_deref() == Some(mat.string.as_str()) {
+            label.push_str(" (current)");
+        }
+
+        Label::new(label, style.label.clone())
+            .with_highlights(mat.positions.clone())
+            .contained()
+            .with_style(style.container)
+            .boxed()
+    }
+}