Implement the desktop command palette

apps/desktop/src/action.rs

@@ -19,6 +19,7 @@ pub enum UiAction {
     CopyEditedField,
     Paste,
     Find,
+    CommandPalette,
     TogglePaneFocus,
     Refresh,
     ReloadEntry,
@@ -47,6 +48,7 @@ impl UiAction {
             Self::CopyEditedField => "copy-edited-field",
             Self::Paste => "paste",
             Self::Find => "find",
+            Self::CommandPalette => "command-palette",
             Self::TogglePaneFocus => "toggle-pane-focus",
             Self::Refresh => "refresh",
             Self::ReloadEntry => "reload-entry",
@@ -107,6 +109,7 @@ pub struct ActionContext {
     pub dirty: bool,
     pub saving: bool,
     pub switching_vault: bool,
+    pub modal_open: bool,
     pub focused_field: bool,
     pub focused_sensitive: bool,
     pub entry_path: bool,
@@ -156,6 +159,12 @@ pub const ACTIONS: &[ActionSpec] = &[
     ),
     spec(UiAction::Paste, MenuGroup::Edit, "Paste", Some("⌘V")),
     spec(UiAction::Find, MenuGroup::Edit, "Find", Some("⌘F")),
+    spec(
+        UiAction::CommandPalette,
+        MenuGroup::View,
+        "Command Palette…",
+        Some("⌘K"),
+    ),
     spec(
         UiAction::TogglePaneFocus,
         MenuGroup::View,
@@ -228,6 +237,7 @@ pub fn shortcut_label(action: UiAction) -> Option<String> {
 pub fn enabled(action: UiAction, context: ActionContext) -> bool {
     match action {
         UiAction::About | UiAction::Settings | UiAction::Help => true,
+        UiAction::CommandPalette => !context.modal_open,
         // Entry creation is not valid until the dedicated workflow exists.
         UiAction::NewEntry => false,
         UiAction::OpenFolder => {
@@ -282,6 +292,95 @@ pub fn enabled(action: UiAction, context: ActionContext) -> bool {
     }
 }
 
+pub fn disabled_reason(action: UiAction, context: ActionContext) -> Option<&'static str> {
+    if enabled(action, context) {
+        return None;
+    }
+    Some(match action {
+        UiAction::NewEntry => "Entry creation is not available yet",
+        UiAction::OpenFolder if !context.storage_ready => "Shared configuration is unavailable",
+        UiAction::OpenFolder if context.saving => "Wait for the active save",
+        UiAction::OpenFolder => "Wait for vault validation",
+        UiAction::OpenEntry if !context.storage_ready => "Shared configuration is unavailable",
+        UiAction::OpenEntry if !context.entry_path => "Enter or select an entry path",
+        UiAction::OpenEntry if context.saving => "Wait for the active save",
+        UiAction::OpenEntry => "Wait for vault validation",
+        UiAction::Save if !context.unlocked => "Unlock the current entry first",
+        UiAction::Save if !context.editing => "Open an entry editor first",
+        UiAction::Save if !context.dirty => "The editor has no changes",
+        UiAction::Save if context.saving => "A save is already running",
+        UiAction::Save => "Wait for vault validation",
+        UiAction::CloseWindow | UiAction::Quit => "Wait for vault validation",
+        UiAction::Undo | UiAction::Redo | UiAction::Cut | UiAction::Paste | UiAction::Find => {
+            "Use the focused native text field"
+        }
+        UiAction::CopyField | UiAction::CopyEditedField if !context.unlocked => {
+            "Unlock an entry first"
+        }
+        UiAction::CopyField | UiAction::CopyEditedField if !context.document_open => {
+            "Open an entry first"
+        }
+        UiAction::CopyField | UiAction::CopyEditedField if !context.focused_field => {
+            "Select a field first"
+        }
+        UiAction::CopyField | UiAction::CopyEditedField if context.switching_vault => {
+            "Wait for vault validation"
+        }
+        UiAction::CopyField => "Use Copy Edited Field while editing",
+        UiAction::CopyEditedField => "Open the entry editor first",
+        UiAction::Refresh if !context.storage_ready => "Shared configuration is unavailable",
+        UiAction::Refresh if context.tree_loading => "A refresh is already running",
+        UiAction::Refresh => "Wait for vault validation",
+        UiAction::ReloadEntry if !context.unlocked => "Unlock an entry first",
+        UiAction::ReloadEntry if !context.document_open => "Open an entry first",
+        UiAction::ReloadEntry if context.saving => "Wait for the active save",
+        UiAction::ReloadEntry => "Wait for vault validation",
+        UiAction::EditEntry if !context.unlocked => "Unlock an entry first",
+        UiAction::EditEntry if !context.document_open => "Open an entry first",
+        UiAction::EditEntry if context.editing => "The entry editor is already open",
+        UiAction::EditEntry => "Wait for vault validation",
+        UiAction::ToggleReveal if !context.unlocked => "Unlock an entry first",
+        UiAction::ToggleReveal if !context.document_open => "Open an entry first",
+        UiAction::ToggleReveal if !context.focused_sensitive => "Select a sensitive field first",
+        UiAction::ToggleReveal => "Wait for vault validation",
+        UiAction::Lock => "The password store is already locked",
+        UiAction::CommandPalette => "Finish the current confirmation first",
+        UiAction::About
+        | UiAction::Settings
+        | UiAction::TogglePaneFocus
+        | UiAction::Minimize
+        | UiAction::Help => "Action is unavailable",
+    })
+}
+
+pub const fn aliases(action: UiAction) -> &'static [&'static str] {
+    match action {
+        UiAction::About => &["version", "license", "credits"],
+        UiAction::Settings => &["preferences", "configuration", "config"],
+        UiAction::NewEntry => &["insert", "add password", "create entry"],
+        UiAction::OpenFolder => &["open vault", "open store", "choose folder"],
+        UiAction::OpenEntry => &["show entry", "view password"],
+        UiAction::Save => &["write", "save entry"],
+        UiAction::CloseWindow => &["close"],
+        UiAction::Quit => &["exit"],
+        UiAction::Undo => &["revert edit"],
+        UiAction::Redo => &["repeat edit"],
+        UiAction::Cut => &["remove selection"],
+        UiAction::CopyField | UiAction::CopyEditedField => &["copy value", "clipboard"],
+        UiAction::Paste => &["insert clipboard"],
+        UiAction::Find => &["search text"],
+        UiAction::CommandPalette => &["commands", "actions", "search commands"],
+        UiAction::TogglePaneFocus => &["next pane", "switch pane", "focus"],
+        UiAction::Refresh => &["reload vault", "refresh tree"],
+        UiAction::ReloadEntry => &["revert entry", "refresh entry"],
+        UiAction::EditEntry => &["modify entry"],
+        UiAction::ToggleReveal => &["show password", "hide password", "reveal field"],
+        UiAction::Lock => &["secure", "log out", "relock"],
+        UiAction::Minimize => &["hide window"],
+        UiAction::Help => &["shortcuts", "documentation"],
+    }
+}
+
 pub fn shortcut_action(key: &keyboard::Key, modifiers: keyboard::Modifiers) -> Option<UiAction> {
     if key.as_ref() == keyboard::Key::Named(Named::Tab) && modifiers.is_empty() {
         return Some(UiAction::TogglePaneFocus);
@@ -305,6 +404,7 @@ pub fn shortcut_action(key: &keyboard::Key, modifiers: keyboard::Modifiers) -> O
         keyboard::Key::Character("c" | "C") => Some(UiAction::CopyField),
         keyboard::Key::Character("v" | "V") => Some(UiAction::Paste),
         keyboard::Key::Character("f" | "F") => Some(UiAction::Find),
+        keyboard::Key::Character("k" | "K") => Some(UiAction::CommandPalette),
         keyboard::Key::Character("r" | "R") => Some(UiAction::Refresh),
         keyboard::Key::Character("l" | "L") => Some(UiAction::Lock),
         keyboard::Key::Character("m" | "M") => Some(UiAction::Minimize),
@@ -328,6 +428,7 @@ mod tests {
             dirty: true,
             saving: false,
             switching_vault: false,
+            modal_open: false,
             focused_field: true,
             focused_sensitive: true,
             entry_path: true,
@@ -417,6 +518,32 @@ mod tests {
         ] {
             assert!(!enabled(action, switching), "{action:?}");
         }
+        for spec in ACTIONS {
+            if !enabled(spec.action, ready) {
+                assert!(
+                    disabled_reason(spec.action, ready).is_some(),
+                    "{:?}",
+                    spec.action
+                );
+            }
+        }
+        assert!(!enabled(
+            UiAction::CommandPalette,
+            ActionContext {
+                modal_open: true,
+                ..ready
+            }
+        ));
+        assert_eq!(
+            disabled_reason(
+                UiAction::CommandPalette,
+                ActionContext {
+                    modal_open: true,
+                    ..ready
+                }
+            ),
+            Some("Finish the current confirmation first")
+        );
     }
 
     #[test]
@@ -426,6 +553,7 @@ mod tests {
             ("o", UiAction::OpenFolder),
             ("s", UiAction::Save),
             ("f", UiAction::Find),
+            ("k", UiAction::CommandPalette),
             ("n", UiAction::NewEntry),
             ("w", UiAction::CloseWindow),
             ("q", UiAction::Quit),

apps/desktop/src/main.rs

@@ -7,6 +7,7 @@ mod folder_picker;
 #[cfg(target_os = "macos")]
 mod native_menu;
 mod navigation;
+mod palette;
 
 use std::{
     path::PathBuf,
@@ -43,6 +44,7 @@ use ironstorage::{
     write::WriteOutcome,
 };
 use navigation::{NavigationIntent, NavigationKey, NavigationTree};
+use palette::CommandPalette;
 use zeroize::Zeroizing;
 
 use action::{ActionContext, MenuGroup, UiAction};
@@ -58,6 +60,9 @@ enum Message {
     Action(UiAction),
     FieldAction(EntryFieldId, UiAction),
     ToggleMenu(MenuGroup),
+    PaletteQueryChanged(String),
+    PaletteCancel,
+    PaletteInvoke(UiAction),
     DismissUtility,
     WindowResolved(UiAction, Option<window::Id>),
     FolderPicked(Result<Option<PathBuf>, String>),
@@ -186,6 +191,7 @@ struct App {
     status: String,
     open_menu: Option<MenuGroup>,
     utility: Option<UtilityView>,
+    palette: CommandPalette,
     #[cfg(target_os = "macos")]
     native_menu: Option<NativeMenu>,
 }
@@ -292,6 +298,7 @@ impl App {
             status: "Loading shared configuration…".to_owned(),
             open_menu: None,
             utility: None,
+            palette: CommandPalette::default(),
             #[cfg(target_os = "macos")]
             native_menu: None,
         };
@@ -310,7 +317,16 @@ impl App {
 
     fn update(&mut self, message: Message) -> Task<Message> {
         match message {
-            Message::Action(action) => return self.invoke_action(action),
+            Message::Action(UiAction::CommandPalette) => return self.toggle_palette(),
+            Message::Action(action) => {
+                if self.palette.is_open() {
+                    self.palette.close();
+                    let restore = self.restore_focus();
+                    let action = self.invoke_action(action);
+                    return Task::batch([restore, action]);
+                }
+                return self.invoke_action(action);
+            }
             Message::FieldAction(id, action) => {
                 if let Some(editor) = self.editor.as_mut() {
                     editor.select(id);
@@ -320,6 +336,21 @@ impl App {
             Message::ToggleMenu(group) => {
                 self.open_menu = (self.open_menu != Some(group)).then_some(group);
             }
+            Message::PaletteQueryChanged(query) => {
+                self.palette.update_query(query);
+                return iced::widget::operation::snap_to(
+                    command_palette_scroll_id(),
+                    scrollable::RelativeOffset::START,
+                );
+            }
+            Message::PaletteCancel => {
+                self.touch_user_activity();
+                if self.palette.is_open() {
+                    self.palette.close();
+                    return self.restore_focus();
+                }
+            }
+            Message::PaletteInvoke(action) => return self.invoke_palette_action(action),
             Message::DismissUtility => self.utility = None,
             Message::WindowResolved(action, id) => {
                 let Some(id) = id else {
@@ -436,6 +467,33 @@ impl App {
             }
             Message::SidebarNavigate(key) => {
                 self.touch_user_activity();
+                if self.palette.is_open() {
+                    return match key {
+                        NavigationKey::Previous => {
+                            self.palette
+                                .move_selection(false, self.palette.results().len());
+                            self.scroll_palette_selection()
+                        }
+                        NavigationKey::Next => {
+                            self.palette
+                                .move_selection(true, self.palette.results().len());
+                            self.scroll_palette_selection()
+                        }
+                        NavigationKey::Activate => self
+                            .palette
+                            .selected_action()
+                            .map_or_else(Task::none, |action| self.invoke_palette_action(action)),
+                        NavigationKey::First => {
+                            self.palette.select_first();
+                            self.scroll_palette_selection()
+                        }
+                        NavigationKey::Last => {
+                            self.palette.select_last(self.palette.results().len());
+                            self.scroll_palette_selection()
+                        }
+                        NavigationKey::Collapse | NavigationKey::Expand => Task::none(),
+                    };
+                }
                 match self.pane_focus {
                     PaneFocus::Sidebar => {
                         let intent = self.navigation.navigate(key);
@@ -708,6 +766,7 @@ impl App {
             dirty: self.editor.as_ref().is_some_and(EntryEditor::is_dirty),
             saving: self.saving,
             switching_vault: self.switching_vault,
+            modal_open: self.confirmation.is_some() || self.generate_confirmation.is_some(),
             focused_field: focused.is_some(),
             focused_sensitive: focused
                 .is_some_and(|field| field.metadata().sensitivity() == EntrySensitivity::Sensitive),
@@ -740,6 +799,7 @@ impl App {
             UiAction::About => self.utility = Some(UtilityView::About),
             UiAction::Settings => self.utility = Some(UtilityView::Settings),
             UiAction::Help => self.utility = Some(UtilityView::Help),
+            UiAction::CommandPalette => return self.toggle_palette(),
             UiAction::OpenFolder => {
                 let initial = self
                     .storage
@@ -778,6 +838,62 @@ impl App {
         Task::none()
     }
 
+    fn toggle_palette(&mut self) -> Task<Message> {
+        if self.palette.is_open() {
+            self.palette.close();
+            return self.restore_focus();
+        }
+        let context = self.action_context();
+        if let Some(reason) = action::disabled_reason(UiAction::CommandPalette, context) {
+            self.status = reason.to_owned();
+            return Task::none();
+        }
+        self.open_menu = None;
+        self.utility = None;
+        self.palette.open();
+        iced::widget::operation::focus(command_palette_input_id())
+    }
+
+    fn invoke_palette_action(&mut self, selected: UiAction) -> Task<Message> {
+        if !self.palette.is_open() {
+            return Task::none();
+        }
+        let context = self.action_context();
+        if let Some(reason) = action::disabled_reason(selected, context) {
+            self.status = format!("{}: {reason}.", action::spec_for(selected).label);
+            return Task::none();
+        }
+        self.palette.close();
+        let restore = self.restore_focus();
+        let action = self.invoke_action(selected);
+        Task::batch([restore, action])
+    }
+
+    fn scroll_palette_selection(&self) -> Task<Message> {
+        let result_count = self.palette.results().len();
+        let y = if result_count <= 1 {
+            0.0
+        } else {
+            self.palette.selected() as f32 / (result_count - 1) as f32
+        };
+        iced::widget::operation::snap_to(
+            command_palette_scroll_id(),
+            scrollable::RelativeOffset { x: 0.0, y },
+        )
+    }
+
+    fn restore_focus(&self) -> Task<Message> {
+        match self.pane_focus {
+            PaneFocus::Sidebar => iced::widget::operation::focus_next(),
+            PaneFocus::Content => iced::widget::operation::focus(
+                self.editor
+                    .as_ref()
+                    .and_then(EntryEditor::focused)
+                    .map_or_else(content_focus_id, editor_field_input_id),
+            ),
+        }
+    }
+
     fn begin_tree_refresh(&mut self) -> Task<Message> {
         let Some(storage) = self.storage.clone() else {
             return Task::none();
@@ -1088,8 +1204,19 @@ impl App {
         .min_size(220)
         .on_resize(8, Message::PaneResized);
 
-        container(
+        let shortcut = if cfg!(target_os = "macos") {
-            column![
+            "⌘K"
+        } else {
+            "Ctrl+K"
+        };
+        let command_input = text_input(
+            &format!("Search commands ({shortcut})"),
+            self.palette.query(),
+        )
+        .id(command_palette_input_id())
+        .on_input(Message::PaletteQueryChanged)
+        .width(Length::Fixed(280.0));
+        let mut chrome = column![
             row![
                 text(authentication),
                 text(
@@ -1100,16 +1227,20 @@ impl App {
                         })
                 )
                 .size(13),
+                command_input,
                 text(&self.status).size(14),
                 text("Tab changes pane focus").size(12),
             ]
             .spacing(16)
             .padding(10),
             platform_menu_bar(self),
-                panes,
+        ];
-            ]
+        if self.palette.is_open() {
-            .height(Length::Fill),
+            chrome = chrome.push(command_palette_results(self));
-        )
+        }
+        chrome = chrome.push(panes);
+
+        container(chrome.height(Length::Fill))
             .width(Length::Fill)
             .height(Length::Fill)
             .into()
@@ -1124,6 +1255,66 @@ fn viewer_scroll_id() -> iced::widget::Id {
     iced::widget::Id::new("desktop-entry-viewer")
 }
 
+fn command_palette_input_id() -> iced::widget::Id {
+    iced::widget::Id::new("desktop-command-palette")
+}
+
+fn command_palette_scroll_id() -> iced::widget::Id {
+    iced::widget::Id::new("desktop-command-palette-results")
+}
+
+fn content_focus_id() -> iced::widget::Id {
+    iced::widget::Id::new("desktop-entry-path")
+}
+
+fn editor_field_input_id(id: EntryFieldId) -> iced::widget::Id {
+    format!("desktop-entry-field-{}", id.value()).into()
+}
+
+fn command_palette_results(app: &App) -> Element<'_, Message> {
+    let context = app.action_context();
+    let results = app.palette.results();
+    if results.is_empty() {
+        return container(text("No matching commands"))
+            .padding([8, 12])
+            .width(Length::Fill)
+            .into();
+    }
+
+    let mut rows = column![].spacing(2).padding([4, 8]);
+    for (index, action) in results.into_iter().enumerate() {
+        let spec = action::spec_for(action);
+        let shortcut = action::shortcut_label(action).unwrap_or_default();
+        let reason = action::disabled_reason(action, context);
+        let availability = reason.unwrap_or("Available");
+        let content = row![
+            text(spec.label).width(Length::Fill),
+            text(shortcut).size(13),
+            text(availability).size(13).width(Length::Fixed(250.0)),
+        ]
+        .spacing(12);
+        let item = button(content)
+            .width(Length::Fill)
+            .style(if index == app.palette.selected() {
+                button::primary
+            } else {
+                button::text
+            });
+        rows = rows.push(if reason.is_none() {
+            item.on_press(Message::PaletteInvoke(action))
+        } else {
+            item
+        });
+    }
+    container(
+        scrollable(rows)
+            .id(command_palette_scroll_id())
+            .height(Length::Fixed(240.0)),
+    )
+    .width(Length::Fill)
+    .into()
+}
+
 fn platform_menu_bar(app: &App) -> Element<'_, Message> {
     if cfg!(target_os = "macos") {
         return container(row![]).height(Length::Fixed(0.0)).into();
@@ -1318,6 +1509,7 @@ fn content_view(app: &App) -> Element<'_, Message> {
         })
         .size(20),
         text_input("Entry path", &app.entry_path)
+            .id(content_focus_id())
             .on_input(Message::EntryPathChanged)
             .on_submit(Message::Action(UiAction::OpenEntry)),
         button("Open").on_press(Message::Action(UiAction::OpenEntry)),
@@ -1549,6 +1741,7 @@ fn editor_view(editor: &EntryEditor, conflict: bool) -> Element<'_, Message> {
             },
             value.unwrap_or(""),
         )
+        .id(editor_field_input_id(id))
         .secure(sensitive && !editor.is_revealed(id))
         .on_input_maybe(
             value
@@ -1696,6 +1889,9 @@ fn poll_lease<B: SecretStoreBackend, C: AuthenticationClock>(
 
 fn event_message(event: &Event) -> Option<Message> {
     if let Event::Keyboard(keyboard::Event::KeyPressed { key, modifiers, .. }) = event {
+        if key.as_ref() == keyboard::Key::Named(keyboard::key::Named::Escape) {
+            return Some(Message::PaletteCancel);
+        }
         if let Some(action) = action::shortcut_action(key, *modifiers) {
             return Some(Message::Action(action));
         }
@@ -1940,6 +2136,7 @@ mod tests {
             status: String::new(),
             open_menu: None,
             utility: None,
+            palette: CommandPalette::default(),
             #[cfg(target_os = "macos")]
             native_menu: None,
         }
@@ -2195,6 +2392,64 @@ mod tests {
         assert!(app.status.contains("Wait for vault validation"));
     }
 
+    #[test]
+    fn command_palette_focus_matching_execution_cancellation_and_availability_are_shared() {
+        let mut app = test_app(None);
+        app.pane_focus = PaneFocus::Content;
+
+        let _focus = app.update(Message::Action(UiAction::CommandPalette));
+        assert!(app.palette.is_open());
+        assert_eq!(app.palette.selected(), 0);
+        let _task = app.update(Message::SidebarNavigate(NavigationKey::Next));
+        assert_eq!(app.palette.selected(), 1);
+        let _task = app.update(Message::SidebarNavigate(NavigationKey::Previous));
+        assert_eq!(app.palette.selected(), 0);
+
+        let _task = app.update(Message::PaletteQueryChanged("about".to_owned()));
+        assert_eq!(app.palette.selected_action(), Some(UiAction::About));
+        let _task = app.update(Message::SidebarNavigate(NavigationKey::Activate));
+        assert!(!app.palette.is_open());
+        assert_eq!(app.utility, Some(UtilityView::About));
+        assert_eq!(app.pane_focus, PaneFocus::Content);
+
+        app.utility = None;
+        let _task = app.update(Message::Action(UiAction::CommandPalette));
+        let _task = app.update(Message::PaletteQueryChanged("lock".to_owned()));
+        assert_eq!(app.palette.selected_action(), Some(UiAction::Lock));
+        let _task = app.update(Message::SidebarNavigate(NavigationKey::Activate));
+        assert!(app.palette.is_open());
+        assert!(app.status.contains("already locked"));
+        let _restore = app.update(Message::PaletteCancel);
+        assert!(!app.palette.is_open());
+        assert!(app.palette.query().is_empty());
+        assert_eq!(app.pane_focus, PaneFocus::Content);
+
+        app.confirmation = Some(PendingAction::CloseWindow(window::Id::unique()));
+        let _task = app.update(Message::Action(UiAction::CommandPalette));
+        assert!(!app.palette.is_open());
+        assert!(app.status.contains("Finish the current confirmation"));
+        app.confirmation = None;
+
+        let _task = app.update(Message::Action(UiAction::CommandPalette));
+        let _task = app.update(Message::PaletteInvoke(UiAction::Settings));
+        assert!(!app.palette.is_open());
+        assert_eq!(app.utility, Some(UtilityView::Settings));
+
+        let escape = Event::Keyboard(keyboard::Event::KeyPressed {
+            key: keyboard::Key::Named(keyboard::key::Named::Escape),
+            modified_key: keyboard::Key::Named(keyboard::key::Named::Escape),
+            physical_key: keyboard::key::Physical::Code(keyboard::key::Code::Escape),
+            location: keyboard::Location::Standard,
+            modifiers: keyboard::Modifiers::NONE,
+            text: None,
+            repeat: false,
+        });
+        assert!(matches!(
+            event_message(&escape),
+            Some(Message::PaletteCancel)
+        ));
+    }
+
     #[test]
     fn vault_switch_result_replaces_state_only_after_storage_success() {
         let (_temporary, storage) = fixture_storage();

apps/desktop/src/native_menu.rs

@@ -125,6 +125,7 @@ fn accelerator(action: UiAction) -> Option<Accelerator> {
         UiAction::Cut => (command, Code::KeyX),
         UiAction::Paste => (command, Code::KeyV),
         UiAction::Find => (command, Code::KeyF),
+        UiAction::CommandPalette => (command, Code::KeyK),
         UiAction::Refresh => (command, Code::KeyR),
         UiAction::Lock => (command, Code::KeyL),
         UiAction::Help => (Modifiers::empty(), Code::F1),

apps/desktop/src/palette.rs

@@ -0,0 +1,186 @@
+//! Deterministic fuzzy matching over the shared desktop action registry.
+
+use crate::action::{self, UiAction};
+
+#[derive(Debug, Default)]
+pub struct CommandPalette {
+    open: bool,
+    query: String,
+    selected: usize,
+}
+
+impl CommandPalette {
+    pub fn is_open(&self) -> bool {
+        self.open
+    }
+
+    pub fn query(&self) -> &str {
+        &self.query
+    }
+
+    pub fn selected(&self) -> usize {
+        self.selected
+    }
+
+    pub fn open(&mut self) {
+        self.open = true;
+        self.query.clear();
+        self.selected = 0;
+    }
+
+    pub fn close(&mut self) {
+        self.open = false;
+        self.query.clear();
+        self.selected = 0;
+    }
+
+    pub fn update_query(&mut self, query: String) {
+        self.open = true;
+        self.query = query;
+        self.selected = 0;
+    }
+
+    pub fn move_selection(&mut self, forward: bool, result_count: usize) {
+        if result_count == 0 {
+            self.selected = 0;
+        } else if forward {
+            self.selected = (self.selected + 1) % result_count;
+        } else {
+            self.selected = self.selected.checked_sub(1).unwrap_or(result_count - 1);
+        }
+    }
+
+    pub fn select_first(&mut self) {
+        self.selected = 0;
+    }
+
+    pub fn select_last(&mut self, result_count: usize) {
+        self.selected = result_count.saturating_sub(1);
+    }
+
+    pub fn results(&self) -> Vec<UiAction> {
+        matches(&self.query)
+    }
+
+    pub fn selected_action(&self) -> Option<UiAction> {
+        self.results().get(self.selected).copied()
+    }
+}
+
+pub fn matches(query: &str) -> Vec<UiAction> {
+    let query = normalize(query);
+    let mut matches = action::ACTIONS
+        .iter()
+        .enumerate()
+        .filter(|(_, spec)| spec.action != UiAction::CommandPalette)
+        .filter_map(|(order, spec)| {
+            std::iter::once(spec.label)
+                .chain(std::iter::once(spec.action.id()))
+                .chain(action::aliases(spec.action).iter().copied())
+                .filter_map(|candidate| fuzzy_score(&query, &normalize(candidate)))
+                .min()
+                .map(|score| (score, order, spec.action))
+        })
+        .collect::<Vec<_>>();
+    matches.sort_by_key(|(score, order, _)| (*score, *order));
+    matches.into_iter().map(|(_, _, action)| action).collect()
+}
+
+fn normalize(value: &str) -> String {
+    value
+        .chars()
+        .flat_map(char::to_lowercase)
+        .filter(|character| character.is_alphanumeric())
+        .collect()
+}
+
+fn fuzzy_score(query: &str, candidate: &str) -> Option<usize> {
+    if query.is_empty() {
+        return Some(0);
+    }
+    if query == candidate {
+        return Some(0);
+    }
+    if candidate.starts_with(query) {
+        return Some(10 + candidate.len().saturating_sub(query.len()));
+    }
+    if let Some(index) = candidate.find(query) {
+        return Some(30 + index + candidate.len().saturating_sub(query.len()));
+    }
+    if let Some(gaps) = subsequence_gaps(query, candidate) {
+        return Some(60 + gaps);
+    }
+    let distance = edit_distance(query, candidate);
+    let tolerance = query.chars().count().div_ceil(3).clamp(1, 3);
+    (distance <= tolerance).then_some(100 + distance * 10 + candidate.len())
+}
+
+fn subsequence_gaps(query: &str, candidate: &str) -> Option<usize> {
+    let mut positions = candidate.char_indices();
+    let mut previous = None;
+    let mut gaps = 0;
+    for expected in query.chars() {
+        let (position, _) = positions.find(|(_, actual)| *actual == expected)?;
+        if let Some(previous) = previous {
+            gaps += position.saturating_sub(previous + 1);
+        }
+        previous = Some(position);
+    }
+    Some(gaps + candidate.len().saturating_sub(query.len()))
+}
+
+fn edit_distance(left: &str, right: &str) -> usize {
+    let right = right.chars().collect::<Vec<_>>();
+    let mut previous = (0..=right.len()).collect::<Vec<_>>();
+    for (left_index, left_character) in left.chars().enumerate() {
+        let mut current = Vec::with_capacity(right.len() + 1);
+        current.push(left_index + 1);
+        for (right_index, right_character) in right.iter().enumerate() {
+            current.push(
+                (previous[right_index + 1] + 1)
+                    .min(current[right_index] + 1)
+                    .min(previous[right_index] + usize::from(left_character != *right_character)),
+            );
+        }
+        previous = current;
+    }
+    previous[right.len()]
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn matching_handles_misspellings_subsequences_aliases_and_stable_order() {
+        assert_eq!(matches("setings").first(), Some(&UiAction::Settings));
+        assert_eq!(matches("rfsh").first(), Some(&UiAction::Refresh));
+        assert_eq!(matches("open vault").first(), Some(&UiAction::OpenFolder));
+        assert_eq!(
+            matches(""),
+            action::ACTIONS
+                .iter()
+                .filter_map(|spec| {
+                    (spec.action != UiAction::CommandPalette).then_some(spec.action)
+                })
+                .collect::<Vec<_>>()
+        );
+    }
+
+    #[test]
+    fn selection_wraps_and_query_changes_reset_it() {
+        let mut palette = CommandPalette::default();
+        palette.open();
+        palette.move_selection(false, 3);
+        assert_eq!(palette.selected(), 2);
+        palette.move_selection(true, 3);
+        assert_eq!(palette.selected(), 0);
+        palette.select_last(3);
+        assert_eq!(palette.selected(), 2);
+        palette.select_first();
+        assert_eq!(palette.selected(), 0);
+        palette.update_query("lock".to_owned());
+        assert_eq!(palette.selected(), 0);
+        assert_eq!(palette.selected_action(), Some(UiAction::Lock));
+    }
+}