//! Pure state mutations on AppState.
//! These don't need channels, async, or PTY runtime.

use std::time::Instant;

use tracing::warn;

use crate::detect::{Agent, AgentState};
use crate::events::AppEvent;
use crate::layout::PaneId;
#[cfg(test)]
use crate::layout::{find_in_direction, NavDirection};
use crate::terminal::{EffectiveStateChange, TerminalStateMutation};
use crate::workspace::WorkspaceGitStatus;

use super::api_helpers::pane_agent_status;
use super::state::{
    AgentNotificationDelivery, AppState, Mode, PaneFocusTarget, PendingAgentNotification,
    ToastKind, ToastNotification, ToastTarget,
};

fn is_background_completion_transition(prev_state: AgentState, new_state: AgentState) -> bool {
    matches!(new_state, AgentState::Idle)
        && matches!(prev_state, AgentState::Working | AgentState::Blocked)
}

fn is_completion_transition(change: &EffectiveStateChange) -> bool {
    is_background_completion_transition(change.previous_state, change.state)
}

fn public_tab_id_for_index(ws: &crate::workspace::Workspace, tab_idx: usize) -> Option<String> {
    let tab_number = ws.public_tab_number(tab_idx)?;
    Some(crate::workspace::public_tab_id_for_number(
        &ws.id, tab_number,
    ))
}

pub fn active_tab_suppresses_notifications(
    is_active_tab: bool,
    outer_terminal_focus: Option<bool>,
) -> bool {
    is_active_tab && outer_terminal_focus != Some(false)
}

pub fn notification_sound_for_state_change(
    suppress_active_tab_notifications: bool,
    prev_state: AgentState,
    new_state: AgentState,
) -> Option<crate::sound::Sound> {
    if new_state == prev_state {
        return None;
    }

    match new_state {
        AgentState::Blocked => Some(crate::sound::Sound::Request),
        AgentState::Idle
            if is_background_completion_transition(prev_state, new_state)
                && !suppress_active_tab_notifications =>
        {
            Some(crate::sound::Sound::Done)
        }
        _ => None,
    }
}

fn notification_sound_for_effective_state_change(
    suppress_active_tab_notifications: bool,
    change: &EffectiveStateChange,
) -> Option<crate::sound::Sound> {
    notification_sound_for_state_change(
        suppress_active_tab_notifications,
        change.previous_state,
        change.state,
    )
}

pub fn notification_toast_for_state_change(
    suppress_active_tab_notifications: bool,
    prev_state: AgentState,
    new_state: AgentState,
) -> Option<ToastKind> {
    if suppress_active_tab_notifications || new_state == prev_state {
        return None;
    }

    match new_state {
        AgentState::Blocked => Some(ToastKind::NeedsAttention),
        AgentState::Idle if is_background_completion_transition(prev_state, new_state) => {
            Some(ToastKind::Finished)
        }
        _ => None,
    }
}

fn notification_toast_for_effective_state_change(
    suppress_active_tab_notifications: bool,
    change: &EffectiveStateChange,
) -> Option<ToastKind> {
    notification_toast_for_state_change(
        suppress_active_tab_notifications,
        change.previous_state,
        change.state,
    )
}

pub fn notification_toast_for_pane_state_update(
    suppress_active_tab_notifications: bool,
    update: &PaneStateUpdate,
) -> Option<ToastKind> {
    if update.suppress_completion
        || suppress_active_tab_notifications
        || update.state == update.previous_state
    {
        return None;
    }

    notification_toast_for_state_change(
        suppress_active_tab_notifications,
        update.previous_state,
        update.state,
    )
}

fn toast_agent_label(agent_label: &str) -> &str {
    agent_label
}

fn toast_event_text(kind: ToastKind) -> &'static str {
    match kind {
        ToastKind::NeedsAttention => "needs attention",
        ToastKind::Finished => "finished",
        ToastKind::UpdateInstalled => "updated",
    }
}

fn sound_for_toast_kind(
    kind: ToastKind,
    suppress_active_tab_notifications: bool,
) -> Option<crate::sound::Sound> {
    match kind {
        ToastKind::NeedsAttention => Some(crate::sound::Sound::Request),
        ToastKind::Finished if !suppress_active_tab_notifications => {
            Some(crate::sound::Sound::Done)
        }
        ToastKind::Finished | ToastKind::UpdateInstalled => None,
    }
}

pub fn notification_context(
    ws: &crate::workspace::Workspace,
    workspace_label: &str,
    ws_idx: usize,
    pane_id: PaneId,
) -> String {
    let mut context = format!("{} · {}", workspace_label, ws_idx + 1);
    if ws.tabs.len() > 1 {
        if let Some(tab_idx) = ws.find_tab_index_for_pane(pane_id) {
            if let Some(label) = ws.tab_display_name(tab_idx) {
                context.push_str(&format!(" · {label}"));
            }
        }
    }
    context
}

#[derive(Debug, Clone, PartialEq, Eq)]
pub struct PaneStateUpdate {
    pub pane_id: PaneId,
    pub ws_idx: usize,
    pub previous_agent_label: Option<String>,
    pub previous_known_agent: Option<Agent>,
    pub previous_state: AgentState,
    pub previous_seen: bool,
    pub previous_presentation: crate::terminal::EffectivePresentation,
    pub agent_label: Option<String>,
    pub known_agent: Option<Agent>,
    pub state: AgentState,
    pub seen: bool,
    pub presentation: crate::terminal::EffectivePresentation,
    pub agent_name_changed: bool,
    pub agent_released: bool,
    pub agent_release_status: Option<crate::api::schema::AgentStatus>,
    pub suppress_completion: bool,
}

// ---------------------------------------------------------------------------
// Focus tracking
// ---------------------------------------------------------------------------

impl AppState {
    pub(crate) fn current_pane_focus_target(&self) -> Option<PaneFocusTarget> {
        let ws_idx = self.active?;
        let ws = self.workspaces.get(ws_idx)?;
        let pane_id = ws.focused_pane_id()?;
        Some(PaneFocusTarget {
            workspace_id: ws.id.clone(),
            pane_id,
        })
    }

    pub(crate) fn record_pane_focus_change(
        &mut self,
        previous: Option<PaneFocusTarget>,
        ws_idx: usize,
        pane_id: PaneId,
    ) {
        let Some(ws) = self.workspaces.get(ws_idx) else {
            return;
        };
        let target = PaneFocusTarget {
            workspace_id: ws.id.clone(),
            pane_id,
        };
        if previous.as_ref() != Some(&target) {
            self.previous_pane_focus = previous;
        }
    }

    fn record_pane_focus_after_navigation(&mut self, previous: Option<PaneFocusTarget>) {
        let current = self.current_pane_focus_target();
        if previous != current {
            self.previous_pane_focus = previous;
        }
    }

    pub(crate) fn focus_pane_in_workspace(&mut self, ws_idx: usize, pane_id: PaneId) -> bool {
        let Some(ws) = self.workspaces.get(ws_idx) else {
            return false;
        };
        let Some(tab_idx) = ws.find_tab_index_for_pane(pane_id) else {
            return false;
        };
        let previous = self.current_pane_focus_target();
        let target = PaneFocusTarget {
            workspace_id: ws.id.clone(),
            pane_id,
        };
        if previous.as_ref() == Some(&target) {
            return false;
        }

        self.switch_workspace_tab(ws_idx, tab_idx);
        if let Some(tab) = self
            .workspaces
            .get_mut(ws_idx)
            .and_then(|ws| ws.tabs.get_mut(tab_idx))
        {
            tab.layout.focus_pane(pane_id);
            self.previous_pane_focus = previous;
            self.mark_session_dirty();
            return true;
        }
        false
    }
}

// ---------------------------------------------------------------------------
// Workspace operations
// ---------------------------------------------------------------------------

impl AppState {
    pub(crate) fn next_agent_metadata_expiry(&self) -> Option<std::time::Instant> {
        self.terminals
            .values()
            .filter_map(|terminal| terminal.next_agent_metadata_expiry())
            .chain(
                self.terminals
                    .values()
                    .filter_map(|terminal| terminal.metadata_tokens.next_expiry()),
            )
            .chain(
                self.workspaces
                    .iter()
                    .filter_map(|workspace| workspace.metadata_tokens.next_expiry()),
            )
            .min()
    }

    pub(crate) fn expire_agent_metadata_at(
        &mut self,
        scheduled_deadline: std::time::Instant,
        now: std::time::Instant,
    ) -> Vec<PaneStateUpdate> {
        let pane_terminals: Vec<_> = self
            .workspaces
            .iter()
            .enumerate()
            .flat_map(|(ws_idx, ws)| {
                ws.tabs.iter().flat_map(move |tab| {
                    tab.layout
                        .pane_ids()
                        .into_iter()
                        .filter_map(move |pane_id| {
                            ws.pane_state(pane_id)
                                .map(|pane| (ws_idx, pane_id, pane.attached_terminal_id.clone()))
                        })
                })
            })
            .collect();
        pane_terminals
            .into_iter()
            .filter_map(|(ws_idx, pane_id, terminal_id)| {
                let previous_seen = self.workspaces[ws_idx].pane_state(pane_id)?.seen;
                let mutation = self
                    .terminals
                    .get_mut(&terminal_id)?
                    .expire_agent_metadata_at(scheduled_deadline, now)?;
                let change = mutation.effective_state_change?;
                let seen = self.apply_pane_state_change(ws_idx, pane_id, &change, false)?;
                let update = PaneStateUpdate {
                    pane_id,
                    ws_idx,
                    previous_agent_label: change.previous_agent_label.clone(),
                    previous_known_agent: change.previous_known_agent,
                    previous_state: change.previous_state,
                    previous_seen,
                    previous_presentation: change.previous_presentation.clone(),
                    agent_label: change.agent_label.clone(),
                    known_agent: change.known_agent,
                    state: change.state,
                    seen,
                    presentation: change.presentation.clone(),
                    agent_name_changed: false,
                    agent_released: false,
                    agent_release_status: None,
                    suppress_completion: false,
                };
                Some(update)
            })
            .collect()
    }

    pub(crate) fn expire_metadata_tokens(
        &mut self,
        now: std::time::Instant,
    ) -> (Vec<(usize, PaneId)>, Vec<usize>) {
        let pane_terminals = self
            .workspaces
            .iter()
            .enumerate()
            .flat_map(|(ws_idx, workspace)| {
                workspace.tabs.iter().flat_map(move |tab| {
                    tab.layout
                        .pane_ids()
                        .into_iter()
                        .filter_map(move |pane_id| {
                            workspace
                                .pane_state(pane_id)
                                .map(|pane| (ws_idx, pane_id, pane.attached_terminal_id.clone()))
                        })
                })
            })
            .collect::<Vec<_>>();
        let changed_panes = pane_terminals
            .into_iter()
            .filter_map(|(ws_idx, pane_id, terminal_id)| {
                let terminal = self.terminals.get_mut(&terminal_id)?;
                terminal.metadata_tokens.expire_at(now).then(|| {
                    terminal.revision = terminal.revision.saturating_add(1);
                    (ws_idx, pane_id)
                })
            })
            .collect();
        let changed_workspaces = self
            .workspaces
            .iter_mut()
            .enumerate()
            .filter_map(|(ws_idx, workspace)| {
                workspace.metadata_tokens.expire_at(now).then_some(ws_idx)
            })
            .collect();
        (changed_panes, changed_workspaces)
    }

    pub(crate) fn pane_is_in_active_tab(&self, ws_idx: usize, pane_id: PaneId) -> bool {
        let Some(active_ws_idx) = self.active else {
            return false;
        };
        if active_ws_idx != ws_idx {
            return false;
        }
        self.workspaces[ws_idx]
            .find_tab_index_for_pane(pane_id)
            .is_some_and(|tab_idx| tab_idx == self.workspaces[ws_idx].active_tab)
    }

    pub fn switch_workspace(&mut self, idx: usize) {
        if idx < self.workspaces.len() {
            let previous_focus = self.current_pane_focus_target();
            self.active = Some(idx);
            self.selected = idx;
            let workspace_id = self.workspaces[idx].id.clone();
            crate::logging::workspace_focused(&workspace_id);
            self.mark_session_dirty();
            if let Some(ws) = self.workspaces.get_mut(idx) {
                let active_tab = ws.active_tab;
                ws.switch_tab(active_tab);
                let tab_id =
                    public_tab_id_for_index(ws, active_tab).unwrap_or_else(|| workspace_id.clone());
                crate::logging::tab_focused(&workspace_id, &tab_id);
            }
            self.record_pane_focus_after_navigation(previous_focus);
        }
    }

    pub(crate) fn switch_workspace_tab(&mut self, ws_idx: usize, tab_idx: usize) -> bool {
        if ws_idx >= self.workspaces.len() {
            return false;
        }
        if self
            .workspaces
            .get(ws_idx)
            .is_none_or(|ws| tab_idx >= ws.tabs.len())
        {
            return false;
        }

        let previous_focus = self.current_pane_focus_target();
        let workspace_changed = self.active != Some(ws_idx);
        self.active = Some(ws_idx);
        self.selected = ws_idx;
        let workspace_id = self.workspaces[ws_idx].id.clone();
        if workspace_changed {
            crate::logging::workspace_focused(&workspace_id);
        }
        self.mark_session_dirty();
        if let Some(ws) = self.workspaces.get_mut(ws_idx) {
            ws.switch_tab(tab_idx);
            let tab_id =
                public_tab_id_for_index(ws, tab_idx).unwrap_or_else(|| workspace_id.clone());
            crate::logging::tab_focused(&workspace_id, &tab_id);
        }
        self.record_pane_focus_after_navigation(previous_focus);
        true
    }

    #[cfg(test)]
    pub fn switch_tab(&mut self, idx: usize) {
        if let Some(ws_idx) = self.active {
            let previous_focus = self.current_pane_focus_target();
            let Some(ws) = self.workspaces.get_mut(ws_idx) else {
                return;
            };
            ws.switch_tab(idx);
            let workspace_id = ws.id.clone();
            let tab_id = public_tab_id_for_index(ws, idx).unwrap_or_else(|| workspace_id.clone());
            crate::logging::tab_focused(&workspace_id, &tab_id);
            self.mark_session_dirty();
            self.record_pane_focus_after_navigation(previous_focus);
        }
    }

    pub(crate) fn mark_active_tab_seen(&mut self) -> bool {
        let Some(ws_idx) = self.active else {
            return false;
        };
        let Some(tab) = self
            .workspaces
            .get_mut(ws_idx)
            .and_then(crate::workspace::Workspace::active_tab_mut)
        else {
            return false;
        };

        let mut changed = false;
        for pane in tab.panes.values_mut() {
            if !pane.seen {
                pane.seen = true;
                changed = true;
            }
        }
        changed
    }

    pub fn move_workspace(&mut self, source_idx: usize, insert_idx: usize) -> bool {
        if source_idx >= self.workspaces.len() || insert_idx > self.workspaces.len() {
            return false;
        }

        let target_idx = if source_idx < insert_idx {
            insert_idx - 1
        } else {
            insert_idx
        };
        if source_idx == target_idx {
            return false;
        }

        self.mark_session_dirty();

        let active_id = self.active.map(|idx| self.workspaces[idx].id.clone());
        let selected_id = self
            .workspaces
            .get(self.selected)
            .map(|workspace| workspace.id.clone());

        let workspace = self.workspaces.remove(source_idx);
        self.workspaces.insert(target_idx, workspace);

        self.active = active_id.and_then(|id| self.workspaces.iter().position(|ws| ws.id == id));
        self.selected = selected_id
            .and_then(|id| self.workspaces.iter().position(|ws| ws.id == id))
            .unwrap_or(0);
        true
    }

    pub fn move_workspace_block(
        &mut self,
        workspace_ids: &[String],
        before_workspace_id: Option<&str>,
    ) -> bool {
        let moved_ids = workspace_ids
            .iter()
            .map(String::as_str)
            .collect::<std::collections::HashSet<_>>();
        if moved_ids.is_empty()
            || moved_ids.len() != workspace_ids.len()
            || !workspace_ids
                .iter()
                .all(|id| self.workspaces.iter().any(|workspace| workspace.id == *id))
            || before_workspace_id.is_some_and(|id| {
                moved_ids.contains(id)
                    || !self.workspaces.iter().any(|workspace| workspace.id == id)
            })
        {
            return false;
        }

        let mut desired_ids = self
            .workspaces
            .iter()
            .filter(|workspace| !moved_ids.contains(workspace.id.as_str()))
            .map(|workspace| workspace.id.clone())
            .collect::<Vec<_>>();
        let insert_idx = before_workspace_id
            .and_then(|id| desired_ids.iter().position(|candidate| candidate == id))
            .unwrap_or(desired_ids.len());
        desired_ids.splice(insert_idx..insert_idx, workspace_ids.iter().cloned());
        if self
            .workspaces
            .iter()
            .map(|workspace| workspace.id.as_str())
            .eq(desired_ids.iter().map(String::as_str))
        {
            return false;
        }

        let active_id = self.active.map(|idx| self.workspaces[idx].id.clone());
        let selected_id = self
            .workspaces
            .get(self.selected)
            .map(|workspace| workspace.id.clone());
        let desired_positions = desired_ids
            .iter()
            .enumerate()
            .map(|(index, id)| (id.clone(), index))
            .collect::<std::collections::HashMap<_, _>>();

        self.mark_session_dirty();
        self.workspaces.sort_by_key(|workspace| {
            desired_positions
                .get(&workspace.id)
                .copied()
                .unwrap_or(usize::MAX)
        });
        self.active = active_id.and_then(|id| self.workspaces.iter().position(|ws| ws.id == id));
        self.selected = selected_id
            .and_then(|id| self.workspaces.iter().position(|ws| ws.id == id))
            .unwrap_or(0);
        true
    }

    pub(crate) fn terminal_ids_for_workspace(
        &self,
        ws_idx: usize,
    ) -> Vec<crate::terminal::TerminalId> {
        self.workspaces
            .get(ws_idx)
            .into_iter()
            .flat_map(|ws| &ws.tabs)
            .flat_map(|tab| tab.panes.values())
            .map(|pane| pane.attached_terminal_id.clone())
            .collect()
    }

    pub(crate) fn pane_ids_for_workspace(&self, ws_idx: usize) -> Vec<PaneId> {
        self.workspaces
            .get(ws_idx)
            .into_iter()
            .flat_map(|ws| &ws.tabs)
            .flat_map(|tab| tab.layout.pane_ids())
            .collect()
    }

    pub(crate) fn terminal_ids_for_tab(
        &self,
        ws_idx: usize,
        tab_idx: usize,
    ) -> Vec<crate::terminal::TerminalId> {
        self.workspaces
            .get(ws_idx)
            .and_then(|ws| ws.tabs.get(tab_idx))
            .into_iter()
            .flat_map(|tab| tab.panes.values())
            .map(|pane| pane.attached_terminal_id.clone())
            .collect()
    }

    pub(crate) fn pane_ids_for_tab(&self, ws_idx: usize, tab_idx: usize) -> Vec<PaneId> {
        self.workspaces
            .get(ws_idx)
            .and_then(|ws| ws.tabs.get(tab_idx))
            .map(|tab| tab.layout.pane_ids())
            .unwrap_or_default()
    }

    pub(crate) fn terminal_id_for_pane(
        &self,
        ws_idx: usize,
        pane_id: PaneId,
    ) -> Option<crate::terminal::TerminalId> {
        self.workspaces
            .get(ws_idx)?
            .pane_state(pane_id)
            .map(|pane| pane.attached_terminal_id.clone())
    }

    pub(crate) fn remove_unattached_terminal_ids(
        &mut self,
        terminal_ids: impl IntoIterator<Item = crate::terminal::TerminalId>,
    ) {
        for terminal_id in terminal_ids {
            let still_attached = self.workspaces.iter().any(|ws| {
                ws.tabs.iter().any(|tab| {
                    tab.panes
                        .values()
                        .any(|pane| pane.attached_terminal_id == terminal_id)
                })
            });
            if !still_attached
                && self.terminals.remove(&terminal_id).is_some()
                && !self.terminal_runtime_shutdowns.contains(&terminal_id)
            {
                self.terminal_runtime_shutdowns.push(terminal_id);
            }
        }
    }

    pub(crate) fn remove_plugin_pane_records(
        &mut self,
        pane_ids: impl IntoIterator<Item = PaneId>,
    ) {
        let pane_ids = pane_ids.into_iter().collect::<Vec<_>>();
        if self
            .previous_pane_focus
            .as_ref()
            .is_some_and(|focus| pane_ids.contains(&focus.pane_id))
        {
            self.previous_pane_focus = None;
        }
        for pane_id in pane_ids {
            self.plugin_panes.remove(&pane_id);
        }
    }

    pub fn close_selected_workspace(&mut self) {
        if self.workspaces.is_empty() {
            return;
        }
        self.mark_session_dirty();
        let close_indices = self.workspace_close_indices(self.selected);

        let mut terminal_ids = Vec::new();
        let mut pane_ids = Vec::new();
        for idx in &close_indices {
            terminal_ids.extend(self.terminal_ids_for_workspace(*idx));
            pane_ids.extend(self.pane_ids_for_workspace(*idx));
            if let Some(workspace_id) = self.workspaces.get(*idx).map(|ws| ws.id.clone()) {
                crate::logging::workspace_closed(&workspace_id);
            }
        }
        let active_workspace_id = self
            .active
            .and_then(|idx| self.workspaces.get(idx))
            .map(|ws| ws.id.clone());
        self.remove_plugin_pane_records(pane_ids);
        for idx in close_indices.iter().rev() {
            self.workspaces.remove(*idx);
        }
        self.remove_unattached_terminal_ids(terminal_ids);
        if self.workspaces.is_empty() {
            self.active = None;
            self.selected = 0;
        } else {
            // Keep focus on the previously focused workspace
            if let Some(id) = active_workspace_id {
                if let Some(idx) = self.workspaces.iter().position(|ws| ws.id == id) {
                    self.selected = idx;
                }
            }
            if self.selected >= self.workspaces.len() {
                self.selected = self.workspaces.len() - 1;
            }
            self.active = Some(self.selected);
        }
    }
}

// ---------------------------------------------------------------------------
// Pane operations
// ---------------------------------------------------------------------------

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub(crate) enum PaneZoomCommand {
    Toggle,
    On,
    Off,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub(crate) enum PaneZoomNoopReason {
    SinglePane,
    AlreadyZoomed,
    AlreadyUnzoomed,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub(crate) struct PaneZoomOutcome {
    pub changed: bool,
    pub focus_changed: bool,
    pub reason: Option<PaneZoomNoopReason>,
    pub zoomed: bool,
}

impl AppState {
    #[cfg(test)]
    pub fn navigate_pane(&mut self, direction: NavDirection) {
        let Some(ws_idx) = self.active else {
            return;
        };
        let Some(tab) = self.workspaces.get(ws_idx).and_then(|ws| ws.active_tab()) else {
            return;
        };
        let panes = if tab.zoomed {
            tab.layout.panes(self.view.terminal_area)
        } else {
            self.view.pane_infos.clone()
        };

        if let Some(focused) = panes.iter().find(|p| p.is_focused) {
            if let Some(target) = find_in_direction(focused, direction, &panes) {
                self.focus_pane_in_workspace(ws_idx, target);
            }
        }
    }

    #[cfg(test)]
    pub fn swap_pane(&mut self, direction: NavDirection) -> bool {
        let Some(ws_idx) = self.active else {
            return false;
        };
        let Some(tab) = self.workspaces.get(ws_idx).and_then(|ws| ws.active_tab()) else {
            return false;
        };
        let panes = if tab.zoomed {
            tab.layout.panes(self.view.terminal_area)
        } else {
            self.view.pane_infos.clone()
        };

        let Some(focused) = panes.iter().find(|p| p.is_focused) else {
            return false;
        };
        let Some(target) = find_in_direction(focused, direction, &panes) else {
            return false;
        };
        let source = focused.id;
        let Some(tab) = self
            .workspaces
            .get_mut(ws_idx)
            .and_then(|ws| ws.active_tab_mut())
        else {
            return false;
        };
        if tab.layout.swap_panes(source, target) {
            self.mark_session_dirty();
            true
        } else {
            false
        }
    }

    #[cfg(test)]
    pub fn resize_pane(&mut self, direction: NavDirection) {
        if let Some(first) = self.view.pane_infos.first() {
            let area = self
                .view
                .pane_infos
                .iter()
                .fold(first.rect, |acc, p| acc.union(p.rect));
            if let Some(tab) = self
                .active
                .and_then(|i| self.workspaces.get_mut(i))
                .and_then(|ws| ws.active_tab_mut())
            {
                tab.layout.resize_focused(direction, 0.05, area);
                self.mark_session_dirty();
            }
        }
    }

    pub(crate) fn apply_pane_zoom(
        &mut self,
        ws_idx: usize,
        pane_id: PaneId,
        command: PaneZoomCommand,
    ) -> Option<PaneZoomOutcome> {
        let tab_idx = self
            .workspaces
            .get(ws_idx)?
            .find_tab_index_for_pane(pane_id)?;
        let focus_changed = self.focus_pane_in_workspace(ws_idx, pane_id);
        let tab = self
            .workspaces
            .get_mut(ws_idx)
            .and_then(|ws| ws.tabs.get_mut(tab_idx))?;
        if tab.layout.pane_count() <= 1 {
            return Some(PaneZoomOutcome {
                changed: false,
                focus_changed,
                reason: Some(PaneZoomNoopReason::SinglePane),
                zoomed: tab.zoomed,
            });
        }

        let desired = match command {
            PaneZoomCommand::Toggle => !tab.zoomed,
            PaneZoomCommand::On => true,
            PaneZoomCommand::Off => false,
        };
        let reason = match (command, tab.zoomed) {
            (PaneZoomCommand::On, true) => Some(PaneZoomNoopReason::AlreadyZoomed),
            (PaneZoomCommand::Off, false) => Some(PaneZoomNoopReason::AlreadyUnzoomed),
            _ => None,
        };
        if reason.is_some() {
            return Some(PaneZoomOutcome {
                changed: false,
                focus_changed,
                reason,
                zoomed: tab.zoomed,
            });
        }

        tab.zoomed = desired;
        let zoomed = tab.zoomed;
        self.mark_session_dirty();
        Some(PaneZoomOutcome {
            changed: true,
            focus_changed,
            reason: None,
            zoomed,
        })
    }

    #[cfg(test)]
    pub fn toggle_zoom(&mut self) {
        let Some(ws_idx) = self.active else {
            return;
        };
        let Some(pane_id) = self
            .workspaces
            .get(ws_idx)
            .and_then(crate::workspace::Workspace::focused_pane_id)
        else {
            return;
        };
        self.apply_pane_zoom(ws_idx, pane_id, PaneZoomCommand::Toggle);
    }

    pub(crate) fn workspace_close_indices(&self, ws_idx: usize) -> Vec<usize> {
        self.workspaces
            .get(ws_idx)
            .and_then(|ws| ws.worktree_space())
            .filter(|space| !space.is_linked_worktree)
            .map(|space| {
                self.workspaces
                    .iter()
                    .enumerate()
                    .filter_map(|(idx, ws)| {
                        ws.worktree_space()
                            .is_some_and(|member| member.key == space.key)
                            .then_some(idx)
                    })
                    .collect::<Vec<_>>()
            })
            .filter(|indices| indices.len() >= 2)
            .unwrap_or_else(|| vec![ws_idx])
    }

    pub(crate) fn workspace_close_would_close_worktree_group(&self, ws_idx: usize) -> bool {
        self.workspace_close_indices(ws_idx).len() >= 2
    }

    pub(crate) fn confirm_implicit_worktree_group_close(&self, ws_idx: usize) -> bool {
        self.confirm_close && self.workspace_close_would_close_worktree_group(ws_idx)
    }

    #[cfg(test)]
    fn close_focused_pane_would_close_workspace(&self, ws_idx: usize) -> bool {
        self.workspaces.get(ws_idx).is_some_and(|ws| {
            let pane_count = ws
                .active_tab()
                .map(|tab| tab.layout.pane_count())
                .unwrap_or(0);
            pane_count <= 1 && ws.tabs.len() <= 1
        })
    }

    pub(crate) fn close_pane_would_close_workspace(&self, ws_idx: usize, pane_id: PaneId) -> bool {
        self.workspaces.get(ws_idx).is_some_and(|ws| {
            ws.find_tab_index_for_pane(pane_id).is_some_and(|tab_idx| {
                ws.tabs[tab_idx].layout.pane_count() <= 1 && ws.tabs.len() <= 1
            })
        })
    }

    #[cfg(test)]
    /// Close the focused pane. Returns true when the close was deferred to confirmation.
    pub fn close_pane(&mut self) -> bool {
        let active = self.active;
        if active.is_some_and(|ws_idx| {
            self.close_focused_pane_would_close_workspace(ws_idx)
                && self.workspace_close_would_close_worktree_group(ws_idx)
        }) {
            if let Some(ws_idx) = active {
                if self.confirm_implicit_worktree_group_close(ws_idx) {
                    return true;
                }
            }
        }

        self.mark_session_dirty();
        let terminal_ids = active
            .and_then(|i| {
                self.workspaces
                    .get(i)
                    .and_then(|ws| ws.focused_pane_id().map(|pane_id| (i, pane_id)))
            })
            .and_then(|(i, pane_id)| self.terminal_id_for_pane(i, pane_id))
            .into_iter()
            .collect::<Vec<_>>();
        let pane_ids = active
            .and_then(|i| self.workspaces.get(i).and_then(|ws| ws.focused_pane_id()))
            .into_iter()
            .collect::<Vec<_>>();
        let should_close_workspace = active
            .and_then(|i| self.workspaces.get_mut(i))
            .is_some_and(|ws| ws.close_focused());
        self.remove_plugin_pane_records(pane_ids);
        if should_close_workspace {
            if let Some(active) = active {
                self.selected = active;
            }
            self.close_selected_workspace();
        } else {
            self.remove_unattached_terminal_ids(terminal_ids);
        }
        false
    }

    #[cfg(test)]
    /// Close the active tab. Returns true when the close was deferred to confirmation.
    pub fn close_tab(&mut self) -> bool {
        if self.active.is_some_and(|ws_idx| {
            self.workspaces
                .get(ws_idx)
                .is_some_and(|ws| ws.tabs.len() <= 1)
                && self.workspace_close_would_close_worktree_group(ws_idx)
        }) {
            if let Some(ws_idx) = self.active {
                if self.confirm_implicit_worktree_group_close(ws_idx) {
                    return true;
                }
            }
        }

        self.mark_session_dirty();
        let should_close_workspace = self
            .active
            .and_then(|i| self.workspaces.get(i))
            .is_some_and(|ws| ws.tabs.len() <= 1);
        if should_close_workspace {
            if let Some(active) = self.active {
                self.selected = active;
            }
            self.close_selected_workspace();
            return false;
        }
        if let Some(ws_idx) = self.active {
            let terminal_ids = self
                .workspaces
                .get(ws_idx)
                .map(|ws| self.terminal_ids_for_tab(ws_idx, ws.active_tab))
                .unwrap_or_default();
            let pane_ids = self
                .workspaces
                .get(ws_idx)
                .map(|ws| self.pane_ids_for_tab(ws_idx, ws.active_tab))
                .unwrap_or_default();
            let Some(ws) = self.workspaces.get_mut(ws_idx) else {
                return false;
            };
            let workspace_id = ws.id.clone();
            let closing_tab_id =
                public_tab_id_for_index(ws, ws.active_tab).unwrap_or_else(|| workspace_id.clone());
            ws.close_active_tab();
            self.remove_plugin_pane_records(pane_ids);
            self.remove_unattached_terminal_ids(terminal_ids);
            crate::logging::tab_closed(&workspace_id, &closing_tab_id);
        }
        false
    }
}

pub(super) fn url_from_link_target(target: crate::ghostty::LinkTarget) -> Option<String> {
    match target {
        crate::ghostty::LinkTarget::Uri(uri) => Some(uri),
        crate::ghostty::LinkTarget::Text { text, clicked_byte } => {
            url_at_byte(&text, clicked_byte).map(str::to_owned)
        }
    }
}

pub(crate) fn safe_web_url(url: &str) -> Option<&str> {
    (url.starts_with("http://") || url.starts_with("https://")).then_some(url)
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
struct TextCell {
    ch: char,
    start_col: u16,
    end_col: u16,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
struct CellSpan {
    start: usize,
    end: usize,
}

impl CellSpan {
    fn contains(self, idx: usize) -> bool {
        idx >= self.start && idx <= self.end
    }

    fn columns(self, cells: &[TextCell]) -> (u16, u16) {
        (cells[self.start].start_col, cells[self.end].end_col)
    }
}

/// Finds the terminal display-column bounds for the token under a double-click.
///
/// The algorithm first maps text to terminal cells so wide characters and
/// zero-width marks use display columns, then prefers structured spans that
/// users expect to copy whole (URLs and quoted paths), and finally falls back
/// to a separator-delimited token.
pub(crate) fn word_bounds_at_column(row: &str, col: u16) -> Option<(u16, u16)> {
    // Map the row into display cells before doing any word-boundary work.
    let cells = text_cells(row);
    let clicked_idx = cell_index_at_column(&cells, col)?;

    // Prefer spans that can legally include punctuation or spaces.
    let span = url_span_at_column(&cells, clicked_idx)
        .or_else(|| quoted_path_span_at_column(&cells, clicked_idx))
        .or_else(|| token_span_at_column(&cells, clicked_idx))?;

    // Convert the internal cell span back to inclusive terminal columns.
    Some(span.columns(&cells))
}

fn url_at_byte(text: &str, clicked_byte: usize) -> Option<&str> {
    let range = url_byte_range(text, clicked_byte)?;
    text.get(range)
}

pub(super) fn url_byte_range(text: &str, clicked_byte: usize) -> Option<std::ops::Range<usize>> {
    let clicked_idx = text.get(..clicked_byte)?.chars().count();
    let cells = text_cells(text);
    let span = url_span_at_column(&cells, clicked_idx)?;
    let start = byte_index_for_cell(text, span.start);
    let end = byte_index_after_cell(text, span.end);
    safe_web_url(text.get(start..end)?)?;
    Some(start..end)
}

fn token_span_at_column(cells: &[TextCell], clicked_idx: usize) -> Option<CellSpan> {
    if is_word_separator(cells[clicked_idx].ch) {
        return None;
    }

    let mut start = clicked_idx;
    while start > 0 && !is_word_separator(cells[start - 1].ch) {
        start -= 1;
    }

    let mut end = clicked_idx;
    while end + 1 < cells.len() && !is_word_separator(cells[end + 1].ch) {
        end += 1;
    }

    trim_token_edges(cells, CellSpan { start, end }).filter(|span| span.contains(clicked_idx))
}

fn text_cells(row: &str) -> Vec<TextCell> {
    let mut next_col = 0u16;
    row.chars()
        .map(|ch| {
            let width = u16::from(crate::ghostty::unicode_codepoint_width(ch as u32));
            let start_col = if width == 0 {
                next_col.saturating_sub(1)
            } else {
                next_col
            };
            if width > 0 {
                next_col = next_col.saturating_add(width);
            }
            TextCell {
                ch,
                start_col,
                end_col: next_col.saturating_sub(1),
            }
        })
        .collect()
}

fn cell_index_at_column(cells: &[TextCell], col: u16) -> Option<usize> {
    cells
        .iter()
        .position(|cell| cell.start_col <= col && col <= cell.end_col)
}

fn byte_index_for_cell(row: &str, cell_idx: usize) -> usize {
    row.char_indices()
        .nth(cell_idx)
        .map(|(idx, _)| idx)
        .unwrap_or(row.len())
}

fn byte_index_after_cell(row: &str, cell_idx: usize) -> usize {
    row.char_indices()
        .nth(cell_idx.saturating_add(1))
        .map(|(idx, _)| idx)
        .unwrap_or(row.len())
}

fn url_span_at_column(cells: &[TextCell], clicked_idx: usize) -> Option<CellSpan> {
    let mut start = 0;
    while start < cells.len() {
        if starts_with_chars(&cells[start..], "http://")
            || starts_with_chars(&cells[start..], "https://")
        {
            let mut end = start;
            while end + 1 < cells.len() && !cells[end + 1].ch.is_whitespace() {
                end += 1;
            }
            if clicked_idx >= start && clicked_idx <= end {
                let span = trim_url_edges(cells, CellSpan { start, end })?;
                return span.contains(clicked_idx).then_some(span);
            }
            start = end + 1;
        } else {
            start += 1;
        }
    }
    None
}

fn trim_url_edges(cells: &[TextCell], span: CellSpan) -> Option<CellSpan> {
    let start = span.start;
    let mut end = span.end;
    while start <= end && should_trim_trailing_url_cell(cells, start, end) {
        if end == 0 {
            return None;
        }
        end -= 1;
    }
    (start <= end).then_some(CellSpan { start, end })
}

fn should_trim_trailing_url_cell(cells: &[TextCell], start: usize, end: usize) -> bool {
    match cells[end].ch {
        '"' | '\'' | '`' | '.' | ',' | ';' | ':' | '!' | '?' => true,
        ')' => !trailing_url_closer_is_balanced(cells, start, end, '(', ')'),
        ']' => !trailing_url_closer_is_balanced(cells, start, end, '[', ']'),
        '}' => !trailing_url_closer_is_balanced(cells, start, end, '{', '}'),
        _ => false,
    }
}

fn trailing_url_closer_is_balanced(
    cells: &[TextCell],
    start: usize,
    end: usize,
    open: char,
    close: char,
) -> bool {
    let mut balance = 0i32;
    for cell in &cells[start..end] {
        if cell.ch == open {
            balance += 1;
        } else if cell.ch == close {
            balance -= 1;
        }
    }
    balance > 0
}

fn quoted_path_span_at_column(cells: &[TextCell], clicked_idx: usize) -> Option<CellSpan> {
    let clicked = cells.get(clicked_idx)?.ch;
    if clicked == '"' || clicked == '\'' || clicked == '`' {
        return None;
    }

    for quote in ['"', '\'', '`'] {
        let mut start = None;
        for (idx, cell) in cells.iter().copied().enumerate() {
            let ch = cell.ch;
            if ch != quote || is_escaped(cells, idx) {
                continue;
            }
            if let Some(open) = start {
                if clicked_idx > open
                    && clicked_idx < idx
                    && cells[open + 1..idx].iter().any(|cell| cell.ch == '/')
                {
                    return Some(CellSpan {
                        start: open + 1,
                        end: idx - 1,
                    });
                }
                start = None;
            } else {
                start = Some(idx);
            }
        }
    }
    None
}

fn is_escaped(cells: &[TextCell], idx: usize) -> bool {
    let mut slashes = 0;
    let mut cursor = idx;
    while cursor > 0 && cells[cursor - 1].ch == '\\' {
        slashes += 1;
        cursor -= 1;
    }
    slashes % 2 == 1
}

fn starts_with_chars(cells: &[TextCell], prefix: &str) -> bool {
    prefix
        .chars()
        .enumerate()
        .all(|(idx, expected)| cells.get(idx).is_some_and(|cell| cell.ch == expected))
}

fn is_word_separator(ch: char) -> bool {
    ch.is_whitespace()
        || matches!(
            ch,
            '|' | '('
                | ')'
                | '['
                | ']'
                | '{'
                | '}'
                | ','
                | ';'
                | '!'
                | '（'
                | '）'
                | '：'
                | '、'
                | '。'
                | '，'
        )
}

fn trim_token_edges(cells: &[TextCell], span: CellSpan) -> Option<CellSpan> {
    let mut start = span.start;
    let mut end = span.end;
    while start <= end && is_leading_token_wrapper(cells[start].ch) {
        start += 1;
    }
    if start < end && cells[end].ch == '$' && is_trailing_token_wrapper(cells[end - 1].ch) {
        end -= 1;
    }
    while start <= end && is_trailing_token_wrapper(cells[end].ch) {
        if end == 0 {
            return None;
        }
        end -= 1;
    }
    (start <= end).then_some(CellSpan { start, end })
}

fn is_leading_token_wrapper(ch: char) -> bool {
    matches!(ch, '(' | '[' | '{' | '<' | '"' | '\'' | '`')
}

fn is_trailing_token_wrapper(ch: char) -> bool {
    matches!(
        ch,
        ')' | ']' | '}' | '>' | '"' | '\'' | '`' | '.' | ',' | ';' | ':' | '!' | '?'
    )
}

// ---------------------------------------------------------------------------
// Event handling
// ---------------------------------------------------------------------------

impl AppState {
    pub fn apply_workspace_git_statuses(
        &mut self,
        terminal_runtimes: &crate::terminal::TerminalRuntimeRegistry,
        results: Vec<WorkspaceGitStatus>,
    ) -> bool {
        let mut changed = false;
        for result in results {
            let Some(ws_idx) = self
                .workspaces
                .iter()
                .position(|ws| ws.id == result.workspace_id)
            else {
                continue;
            };

            if self.workspaces[ws_idx]
                .resolved_identity_cwd_from(&self.terminals, terminal_runtimes)
                .as_ref()
                != Some(&result.resolved_identity_cwd)
            {
                continue;
            }

            let ws = &mut self.workspaces[ws_idx];
            if ws.cached_identity_cwd != result.resolved_identity_cwd {
                ws.cached_identity_cwd = result.resolved_identity_cwd;
            }
            if ws.cached_auto_label != result.auto_label {
                ws.cached_auto_label = result.auto_label;
                changed |= ws.custom_name.is_none();
            }
            if ws.cached_git_status_key != result.status_cache_key {
                ws.cached_git_status_key = result.status_cache_key;
            }
            if result.demand.branch && ws.cached_git_branch != result.branch {
                ws.cached_git_branch = result.branch;
                changed = true;
            }
            if result.demand.ahead_behind && ws.cached_git_ahead_behind != result.ahead_behind {
                ws.cached_git_ahead_behind = result.ahead_behind;
                changed = true;
            }
            if ws.cached_git_space != result.space {
                ws.cached_git_space = result.space;
                changed = true;
            }
        }
        changed
    }

    pub fn handle_app_event(&mut self, event: AppEvent) -> Vec<PaneStateUpdate> {
        match event {
            AppEvent::PaneDied { pane_id, .. } => {
                self.handle_pane_died(pane_id);
                Vec::new()
            }
            AppEvent::WorktreeRuntimeRestoreFailed { .. } => Vec::new(),
            AppEvent::UpdateReady {
                version,
                install_command,
            } => {
                self.update_available = Some(version.clone());
                self.update_install_command = install_command.clone();
                self.latest_release_notes_available = true;
                self.update_dismissed = true;
                if matches!(
                    self.toast_config.delivery,
                    crate::config::ToastDelivery::Herdr
                ) {
                    self.toast = Some(ToastNotification {
                        kind: ToastKind::UpdateInstalled,
                        title: format!("v{version} available"),
                        context: crate::update::update_install_instruction(&install_command),
                        position: None,
                        target: None,
                    });
                }
                Vec::new()
            }
            AppEvent::AgentDetectionManifestsUpdated {
                updated, status, ..
            } => {
                self.agent_manifest_update_status = status;
                self.refresh_agent_manifest_summaries();
                if !updated.is_empty()
                    && matches!(
                        self.toast_config.delivery,
                        crate::config::ToastDelivery::Herdr
                    )
                {
                    let agent_list = updated
                        .iter()
                        .map(|item| {
                            format!(
                                "{} {}",
                                crate::detect::agent_label(item.agent),
                                item.version
                            )
                        })
                        .collect::<Vec<_>>()
                        .join(", ");
                    self.toast = Some(ToastNotification {
                        kind: ToastKind::UpdateInstalled,
                        title: "Agent detection rules updated".to_string(),
                        context: agent_list,
                        position: None,
                        target: None,
                    });
                }
                Vec::new()
            }
            AppEvent::AgentProcessDetected {
                pane_id,
                agent,
                observed_at,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    Some(terminal.set_detected_agent_process_at(agent, observed_at))
                })
                .into_iter()
                .collect(),
            AppEvent::CodexPromptObserved { pane_id, ready } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.observe_codex_prompt_ready(ready)
                })
                .into_iter()
                .collect(),
            AppEvent::StateChanged {
                pane_id,
                agent,
                state,
                visible_blocker,
                visible_working,
                process_exited,
                observed_at,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    Some(terminal.set_detected_state_with_screen_signals_at(
                        agent,
                        state,
                        visible_blocker,
                        false,
                        visible_working,
                        process_exited,
                        observed_at,
                    ))
                })
                .into_iter()
                .collect(),
            AppEvent::HookStateReported {
                pane_id,
                source,
                agent_label,
                state,
                message,
                seq,
                session_ref,
            } => {
                if crate::agent_resume::is_reserved_native_state_source(&source, &agent_label) {
                    self.update_terminal_state(pane_id, |terminal| {
                        terminal.set_agent_session_ref(source, agent_label, session_ref, seq)
                    })
                    .into_iter()
                    .collect()
                } else {
                    self.update_terminal_state(pane_id, |terminal| {
                        terminal.set_hook_authority_with_session_ref(
                            source,
                            agent_label,
                            state,
                            message,
                            session_ref,
                            seq,
                        )
                    })
                    .into_iter()
                    .collect()
                }
            }
            AppEvent::AgentResumeReported {
                pane_id,
                source,
                agent_label,
                seq,
                argv,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.record_reported_resume(&source, &agent_label, seq, argv);
                    None
                })
                .into_iter()
                .collect(),
            AppEvent::ReportedAgentShellReturned {
                pane_id,
                observed_at,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.clear_self_reported_agent(observed_at)
                })
                .into_iter()
                .collect(),
            AppEvent::AgentSessionReported {
                pane_id,
                source,
                agent_label,
                seq,
                session_ref,
                session_start_source,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.set_agent_session_ref_for_session_start(
                        source,
                        agent_label,
                        session_ref,
                        seq,
                        session_start_source,
                    )
                })
                .into_iter()
                .collect(),
            AppEvent::HookMetadataReported {
                pane_id,
                source,
                agent_label,
                applies_to_source,
                title,
                display_agent,
                state_labels,
                clear_title,
                clear_display_agent,
                clear_state_labels,
                seq,
                ttl,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.set_agent_metadata(crate::terminal::AgentMetadataReport {
                        source,
                        agent_label,
                        applies_to_source,
                        title,
                        display_agent,
                        state_labels,
                        clear_title,
                        clear_display_agent,
                        clear_state_labels,
                        ttl,
                        seq,
                    })
                })
                .into_iter()
                .collect(),
            AppEvent::HookAuthorityCleared {
                pane_id,
                source,
                seq,
            } => self
                .update_terminal_state(pane_id, |terminal| {
                    terminal.clear_hook_authority_with_mutation(source.as_deref(), seq)
                })
                .into_iter()
                .collect(),
            AppEvent::HookAgentReleased {
                pane_id,
                source,
                agent_label,
                seq,
                ..
            } => {
                if crate::agent_resume::is_official_agent_source(&source, &agent_label) {
                    Vec::new()
                } else {
                    self.update_terminal_state(pane_id, |terminal| {
                        terminal.release_agent_with_mutation(&source, &agent_label, seq)
                    })
                    .into_iter()
                    .collect()
                }
            }
            // Host-local effects are intercepted by HeadlessServer and forwarded to the
            // foreground client; they never touch AppState. Kept for AppEvent exhaustiveness.
            AppEvent::TerminalBell { .. } => Vec::new(),
            AppEvent::ClipboardWrite { .. } => Vec::new(),
            AppEvent::TerminalCwdReported { pane_id, cwd } => {
                if !cwd.is_absolute() || !cwd.is_dir() {
                    return Vec::new();
                }
                let Some(terminal_id) = self.workspaces.iter().find_map(|ws| {
                    ws.pane_state(pane_id)
                        .map(|pane| pane.attached_terminal_id.clone())
                }) else {
                    return Vec::new();
                };
                let Some(terminal) = self.terminals.get_mut(&terminal_id) else {
                    return Vec::new();
                };
                if terminal.cwd != cwd {
                    terminal.cwd = cwd;
                    self.mark_session_dirty();
                }
                Vec::new()
            }
            AppEvent::GitStatusRefreshed {
                results,
                cache_updates,
            } => {
                let _ = results;
                let _ = cache_updates;
                Vec::new()
            }
            AppEvent::WorktreeAddFinished(_) => Vec::new(),
            AppEvent::WorktreeRemoveFinished(_) => Vec::new(),
            AppEvent::WorktreeReadFinished(_) => Vec::new(),
            AppEvent::TabBarCommandFinished { .. } => Vec::new(),
            AppEvent::PluginCommandFinished { .. } => Vec::new(),
        }
    }

    fn update_terminal_state<F>(&mut self, pane_id: PaneId, update: F) -> Option<PaneStateUpdate>
    where
        F: FnOnce(&mut crate::terminal::TerminalState) -> Option<TerminalStateMutation>,
    {
        self.update_terminal_state_with_completion_policy(pane_id, false, update)
    }

    fn update_terminal_state_with_completion_policy<F>(
        &mut self,
        pane_id: PaneId,
        force_suppress_completion: bool,
        update: F,
    ) -> Option<PaneStateUpdate>
    where
        F: FnOnce(&mut crate::terminal::TerminalState) -> Option<TerminalStateMutation>,
    {
        let ws_idx = self
            .workspaces
            .iter()
            .position(|ws| ws.pane_state(pane_id).is_some())?;
        let terminal_id = self.workspaces[ws_idx]
            .pane_state(pane_id)?
            .attached_terminal_id
            .clone();
        let previous_seen = self.workspaces[ws_idx].pane_state(pane_id)?.seen;
        let now = Instant::now();
        let (
            mutation,
            managed_changed,
            agent_name_changed,
            unchanged_change,
            suppress_acquisition_completion,
            completion_reset,
        ) = {
            let terminal = self.terminals.get_mut(&terminal_id)?;
            let previous_agent_name = terminal.agent_name.clone();
            let had_completion = terminal.last_agent_completion_seq.is_some() || !previous_seen;
            let resume_revision = terminal.reported_resume_revision();
            let mutation = update(terminal);
            terminal.reconcile_reported_resume();
            // Resume-only changes return no mutation but must still be saved.
            if terminal.reported_resume_revision() != resume_revision {
                self.session_dirty = true;
            }
            let mutation = mutation?;
            let completion_reset = mutation.session_ref_changed
                || mutation
                    .effective_state_change
                    .as_ref()
                    .is_some_and(|change| change.previous_agent_label != change.agent_label);
            if completion_reset {
                terminal.last_agent_completion_seq = None;
            }
            let managed_changed = terminal.reconcile_managed_agent_at(now, false);
            let suppress_acquisition_completion = terminal.finish_agent_process_acquisition();
            let agent_name_changed = terminal.agent_name != previous_agent_name;
            let unchanged_change = (mutation.agent_released
                || agent_name_changed
                || (completion_reset && had_completion))
                .then(|| terminal.unchanged_effective_state_change_at(now));
            (
                mutation,
                managed_changed,
                agent_name_changed,
                unchanged_change,
                suppress_acquisition_completion,
                completion_reset,
            )
        };
        if completion_reset {
            self.pending_agent_notifications.remove(&pane_id);
            self.workspaces[ws_idx].pane_state_mut(pane_id)?.seen = true;
        }
        if mutation.session_ref_changed || managed_changed || agent_name_changed {
            self.mark_session_dirty();
        }
        let agent_released = mutation.agent_released;
        let change = mutation.effective_state_change.or(unchanged_change)?;
        let suppress_completion = force_suppress_completion
            || (change.state == AgentState::Idle && suppress_acquisition_completion);
        if change.previous_state != change.state {
            self.next_agent_state_change_seq += 1;
            if let Some(terminal) = self.terminals.get_mut(&terminal_id) {
                terminal.last_agent_state_change_seq = Some(self.next_agent_state_change_seq);
                terminal.last_agent_completion_seq = (!suppress_completion
                    && is_completion_transition(&change))
                .then_some(self.next_agent_state_change_seq);
            }
        }
        let seen = self.apply_pane_state_change(ws_idx, pane_id, &change, suppress_completion)?;
        let update = PaneStateUpdate {
            pane_id,
            ws_idx,
            previous_agent_label: change.previous_agent_label.clone(),
            previous_known_agent: change.previous_known_agent,
            previous_state: change.previous_state,
            previous_seen,
            previous_presentation: change.previous_presentation.clone(),
            agent_label: if agent_released {
                change.previous_agent_label.clone()
            } else {
                change.agent_label.clone()
            },
            known_agent: if agent_released {
                change.previous_known_agent
            } else {
                change.known_agent
            },
            state: change.state,
            seen,
            presentation: change.presentation.clone(),
            agent_name_changed,
            agent_released,
            agent_release_status: agent_released.then(|| pane_agent_status(change.state, seen)),
            suppress_completion,
        };
        Some(update)
    }

    pub(crate) fn next_managed_agent_deadline(&self) -> Option<Instant> {
        self.terminals
            .values()
            .filter_map(crate::terminal::TerminalState::next_managed_agent_deadline)
            .min()
    }

    pub(crate) fn publish_pane_process_exit_if_agent(
        &mut self,
        pane_id: PaneId,
        suppress_completion: bool,
    ) -> Option<PaneStateUpdate> {
        let observed_at = std::time::Instant::now();
        let update = self.update_terminal_state_with_completion_policy(
            pane_id,
            suppress_completion,
            |terminal| {
                let agent = terminal.effective_known_agent().or(terminal.detected_agent);
                if agent.is_none() && !terminal.full_lifecycle_hook_authority_active() {
                    return None;
                }
                Some(terminal.set_detected_state_with_screen_signals_at(
                    agent,
                    AgentState::Idle,
                    false,
                    true,
                    false,
                    true,
                    observed_at,
                ))
            },
        )?;
        update.agent_released.then_some(update)
    }

    fn apply_pane_state_change(
        &mut self,
        ws_idx: usize,
        pane_id: PaneId,
        change: &EffectiveStateChange,
        suppress_completion: bool,
    ) -> Option<bool> {
        let is_active_tab = self.pane_is_in_active_tab(ws_idx, pane_id);
        let suppress_active_tab_notifications =
            active_tab_suppresses_notifications(is_active_tab, self.outer_terminal_focus);
        let pane = self.workspaces[ws_idx]
            .tabs
            .iter_mut()
            .find_map(|tab| tab.panes.get_mut(&pane_id))?;

        if change.state != AgentState::Idle {
            pane.seen = true;
        } else if !suppress_completion && is_completion_transition(change) {
            pane.seen = suppress_active_tab_notifications;
        }
        let seen = pane.seen;

        if !suppress_completion {
            if let Some(delivery) =
                self.record_or_deliver_agent_notification(ws_idx, pane_id, change)
            {
                self.apply_agent_notification_delivery(&delivery);
            }
        }

        Some(seen)
    }

    fn record_or_deliver_agent_notification(
        &mut self,
        ws_idx: usize,
        pane_id: PaneId,
        change: &EffectiveStateChange,
    ) -> Option<AgentNotificationDelivery> {
        self.pending_agent_notifications.remove(&pane_id);

        let is_active_tab = self.pane_is_in_active_tab(ws_idx, pane_id);
        let suppress_active_tab_notifications =
            active_tab_suppresses_notifications(is_active_tab, self.outer_terminal_focus);

        let client_notification_kind = notification_toast_for_effective_state_change(
            suppress_active_tab_notifications,
            change,
        );
        let sound = notification_sound_for_effective_state_change(
            suppress_active_tab_notifications,
            change,
        );
        if client_notification_kind.is_none() && sound.is_none() {
            return None;
        }

        let agent_label = change
            .agent_label
            .clone()
            .or_else(|| change.previous_agent_label.clone())?;
        let known_agent = change.known_agent.or(change.previous_known_agent);
        let kind = client_notification_kind.unwrap_or(match sound {
            Some(crate::sound::Sound::Request) => ToastKind::NeedsAttention,
            Some(crate::sound::Sound::Done) | None => ToastKind::Finished,
        });
        let workspace_id = self.workspaces[ws_idx].id.clone();

        if self.toast_config.delay_seconds == 0 {
            return self.agent_notification_delivery(
                ws_idx,
                pane_id,
                workspace_id,
                agent_label,
                known_agent,
                kind,
                change.state,
            );
        }

        self.pending_agent_notifications.insert(
            pane_id,
            PendingAgentNotification {
                pane_id,
                workspace_id,
                agent_label,
                known_agent,
                kind,
                state: change.state,
                deadline: {
                    let now = std::time::Instant::now();
                    let delay_seconds = self
                        .toast_config
                        .delay_seconds
                        .min(crate::config::MAX_TOAST_DELAY_SECONDS);
                    now.checked_add(std::time::Duration::from_secs(delay_seconds))
                        .unwrap_or(now)
                },
            },
        );
        None
    }

    fn agent_notification_delivery(
        &self,
        ws_idx: usize,
        pane_id: PaneId,
        workspace_id: String,
        agent_label: String,
        known_agent: Option<Agent>,
        kind: ToastKind,
        expected_state: AgentState,
    ) -> Option<AgentNotificationDelivery> {
        let terminal_state = self
            .workspaces
            .get(ws_idx)?
            .pane_state(pane_id)
            .and_then(|pane| self.terminals.get(&pane.attached_terminal_id))?;
        if terminal_state.state != expected_state {
            return None;
        }
        if terminal_state
            .effective_agent_label()
            .is_some_and(|current| current != agent_label)
        {
            return None;
        }

        let is_active_tab = self.pane_is_in_active_tab(ws_idx, pane_id);
        let suppress_active_tab_notifications =
            active_tab_suppresses_notifications(is_active_tab, self.outer_terminal_focus);
        let sound = sound_for_toast_kind(kind, suppress_active_tab_notifications)
            .filter(|_| self.sound.allows(known_agent));
        let build_toast = || {
            let workspace_label =
                self.workspaces[ws_idx].display_name_from_terminals(&self.terminals);
            let context =
                notification_context(&self.workspaces[ws_idx], &workspace_label, ws_idx, pane_id);
            ToastNotification {
                kind,
                title: format!(
                    "{} {}",
                    toast_agent_label(&agent_label),
                    toast_event_text(kind)
                ),
                context,
                position: None,
                target: Some(ToastTarget {
                    workspace_id: workspace_id.clone(),
                    pane_id,
                }),
            }
        };
        let toast = (!is_active_tab).then(build_toast);
        let client_notification = (!suppress_active_tab_notifications).then(build_toast);

        if toast.is_none() && client_notification.is_none() && sound.is_none() {
            return None;
        }

        Some(AgentNotificationDelivery {
            pane_id,
            workspace_id,
            agent_label,
            known_agent,
            kind,
            toast,
            client_notification,
            sound,
        })
    }

    fn apply_agent_notification_delivery(&mut self, delivery: &AgentNotificationDelivery) {
        if matches!(
            self.toast_config.delivery,
            crate::config::ToastDelivery::Herdr
        ) {
            if let Some(toast) = delivery.toast.clone() {
                self.toast = Some(toast);
            }
        }
    }

    pub fn next_pending_agent_notification_deadline(&self) -> Option<std::time::Instant> {
        self.pending_agent_notifications
            .values()
            .map(|pending| pending.deadline)
            .min()
    }

    pub fn drain_due_agent_notifications(
        &mut self,
        now: std::time::Instant,
    ) -> Vec<AgentNotificationDelivery> {
        let due_panes: Vec<PaneId> = self
            .pending_agent_notifications
            .iter()
            .filter_map(|(&pane_id, pending)| (pending.deadline <= now).then_some(pane_id))
            .collect();
        let mut deliveries = Vec::new();

        for pane_id in due_panes {
            let Some(pending) = self.pending_agent_notifications.remove(&pane_id) else {
                continue;
            };
            let Some(ws_idx) = self
                .workspaces
                .iter()
                .position(|ws| ws.id == pending.workspace_id)
            else {
                continue;
            };
            let Some(delivery) = self.agent_notification_delivery(
                ws_idx,
                pending.pane_id,
                pending.workspace_id,
                pending.agent_label,
                pending.known_agent,
                pending.kind,
                pending.state,
            ) else {
                continue;
            };
            self.apply_agent_notification_delivery(&delivery);
            deliveries.push(delivery);
        }

        deliveries
    }

    fn handle_pane_died(&mut self, pane_id: PaneId) {
        self.pending_agent_notifications.remove(&pane_id);
        self.remove_plugin_pane_records([pane_id]);
        let ws_idx = self
            .workspaces
            .iter()
            .position(|ws| ws.find_tab_index_for_pane(pane_id).is_some());

        let Some(ws_idx) = ws_idx else {
            warn!(pane = pane_id.raw(), "PaneDied for unknown pane");
            return;
        };

        let pane_terminal_id = self.terminal_id_for_pane(ws_idx, pane_id);
        let workspace_terminal_ids = self.terminal_ids_for_workspace(ws_idx);
        self.pane_id_aliases.retain(|_, alias| *alias != pane_id);
        self.public_pane_id_aliases
            .retain(|_, alias| *alias != pane_id);
        let should_close_workspace = {
            let ws = &mut self.workspaces[ws_idx];
            ws.remove_pane(pane_id)
        };
        self.mark_session_dirty();

        if should_close_workspace {
            let active_workspace_id = self
                .active
                .and_then(|idx| self.workspaces.get(idx))
                .map(|ws| ws.id.clone());
            let selected_workspace_id = self.workspaces.get(self.selected).map(|ws| ws.id.clone());
            self.workspaces.remove(ws_idx);
            self.remove_unattached_terminal_ids(workspace_terminal_ids);
            if self.workspaces.is_empty() {
                self.active = None;
                self.selected = 0;
                if self.mode == Mode::Terminal {
                    self.mode = Mode::Navigate;
                }
            } else {
                // Keep focus on the previously focused workspace
                if let Some(id) = active_workspace_id {
                    if let Some(idx) = self.workspaces.iter().position(|ws| ws.id == id) {
                        self.active = Some(idx);
                    }
                }
                if let Some(active) = self.active {
                    if active >= self.workspaces.len() {
                        self.active = Some(self.workspaces.len() - 1);
                    }
                }
                if let Some(id) = selected_workspace_id {
                    if let Some(idx) = self.workspaces.iter().position(|ws| ws.id == id) {
                        self.selected = idx;
                    }
                }
                if self.selected >= self.workspaces.len() {
                    self.selected = self.workspaces.len() - 1;
                }
            }
        } else {
            self.remove_unattached_terminal_ids(pane_terminal_id);
        }
    }
}

// ---------------------------------------------------------------------------
// Tests
// ---------------------------------------------------------------------------

#[cfg(test)]
mod tests {
    use super::*;
    use crate::detect::{Agent, AgentState};
    use crate::workspace::Workspace;
    use ratatui::layout::Direction;

    fn app_with_workspaces(names: &[&str]) -> AppState {
        let mut state = AppState::test_new();
        state.toast_config.delay_seconds = 0;
        for name in names {
            let ws = Workspace::test_new(name);
            state.workspaces.push(ws);
        }
        state.ensure_test_terminals();
        if !state.workspaces.is_empty() {
            state.active = Some(0);
            state.mode = Mode::Terminal;
        }
        state
    }

    fn mark_linked_worktree(state: &mut AppState, ws_idx: usize) {
        state.workspaces[ws_idx].worktree_space = Some(crate::workspace::WorktreeSpaceMembership {
            key: "repo-key".into(),
            label: "herdr".into(),
            repo_root: "/repo/herdr".into(),
            checkout_path: format!("/repo/worktree-{ws_idx}").into(),
            is_linked_worktree: true,
        });
    }

    fn mark_parent_worktree(state: &mut AppState, ws_idx: usize) {
        state.workspaces[ws_idx].worktree_space = Some(crate::workspace::WorktreeSpaceMembership {
            key: "repo-key".into(),
            label: "herdr".into(),
            repo_root: "/repo/herdr".into(),
            checkout_path: "/repo/herdr".into(),
            is_linked_worktree: false,
        });
    }

    #[test]
    fn notification_context_formats_resolved_workspace_label() {
        let state = app_with_workspaces(&["stale"]);
        let root = state.workspaces[0].tabs[0].root_pane;

        assert_eq!(
            notification_context(&state.workspaces[0], "__herdr_projects__", 0, root),
            "__herdr_projects__ · 1"
        );
    }

    fn selected_word(row: &str, col: u16) -> Option<String> {
        let (start, end) = word_bounds_at_column(row, col)?;
        Some(text_in_cell_range(row, start, end))
    }

    fn selected_url<'a>(row: &'a str, click: &str) -> Option<&'a str> {
        url_at_byte(row, row.find(click)?)
    }

    fn text_in_cell_range(row: &str, start_col: u16, end_col: u16) -> String {
        text_cells(row)
            .into_iter()
            .filter(|cell| cell.start_col >= start_col && cell.end_col <= end_col)
            .map(|cell| cell.ch)
            .collect()
    }

    fn col_of(row: &str, needle: &str) -> u16 {
        let byte_idx = row
            .find(needle)
            .unwrap_or_else(|| panic!("{needle:?} not found in {row:?}"));
        let prefix = &row[..byte_idx];
        prefix
            .chars()
            .map(|ch| u16::from(crate::ghostty::unicode_codepoint_width(ch as u32)))
            .sum()
    }

    fn assert_selects(row: &str, click: &str, expected: &str) {
        assert_eq!(
            selected_word(row, col_of(row, click)).as_deref(),
            Some(expected),
            "row={row:?}, click={click:?}"
        );
    }

    fn assert_selects_nothing(row: &str, click: &str) {
        assert_eq!(
            selected_word(row, col_of(row, click)),
            None,
            "row={row:?}, click={click:?}"
        );
    }

    #[test]
    fn double_click_word_bounds_cover_terminal_text() {
        let cases = [
            (
                "see https://example.com/a-b_c?q=x@y.",
                "example.com",
                "https://example.com/a-b_c?q=x@y",
            ),
            (
                "open \"https://example.com/a,b;c?q=x\";",
                "example.com",
                "https://example.com/a,b;c?q=x",
            ),
            (
                "see https://en.wikipedia.org/wiki/Foo_(bar_(baz)),",
                "wikipedia",
                "https://en.wikipedia.org/wiki/Foo_(bar_(baz))",
            ),
            (
                "see https://example.com/a(b[c{d}e]f),",
                "example.com",
                "https://example.com/a(b[c{d}e]f)",
            ),
            (
                "see (https://example.com/a(b(c)d)))",
                "example.com",
                "https://example.com/a(b(c)d)",
            ),
            (
                "open /tmp/foo-bar/baz_qux/",
                "foo-bar",
                "/tmp/foo-bar/baz_qux/",
            ),
            (
                "open ./src/app/actions.rs:795",
                "actions",
                "./src/app/actions.rs:795",
            ),
            (
                "open ../herdr-worktrees/issue-1",
                "herdr",
                "../herdr-worktrees/issue-1",
            ),
            (
                "edit src/app/actions.rs,then",
                "actions",
                "src/app/actions.rs",
            ),
            (
                "cat \"/tmp/build output/log.txt\"",
                "output",
                "/tmp/build output/log.txt",
            ),
            (
                "cat '/Users/me/Library/Application Support/app/config.json'",
                "Support",
                "/Users/me/Library/Application Support/app/config.json",
            ),
            ("echo 你好-world done", "好", "你好-world"),
            (
                "註解已補（slice 4 5b5fcc0715）：整合原本",
                "5b5fcc0715",
                "5b5fcc0715",
            ),
            ("先跑 cargo test", "cargo", "cargo"),
            (
                "export PATH=$HOME/.cargo/bin:$PATH",
                "$HOME",
                "PATH=$HOME/.cargo/bin:$PATH",
            ),
            (
                "git checkout feature/foo-bar_baz",
                "foo",
                "feature/foo-bar_baz",
            ),
            ("refs #123 and @owner/name", "#123", "#123"),
            ("refs #123 and @owner/name", "owner", "@owner/name"),
            ("cargo test --package=herdr", "--package", "--package=herdr"),
            (
                "cargo test app::actions::tests",
                "app::",
                "app::actions::tests",
            ),
            (
                "image ghcr.io/org/app:latest",
                "ghcr",
                "ghcr.io/org/app:latest",
            ),
            ("ERROR [worker-1] request_id=abc-123", "worker", "worker-1"),
            (
                "tmux|newhoo|fixhoo|newmoo|notification|window_bell|herdr",
                "newhoo",
                "newhoo",
            ),
            (
                "render_status_line(app, area)",
                "render",
                "render_status_line",
            ),
            ("render_status_line(app, area)", "app", "app"),
            ("render_status_line(app, area)", "area", "area"),
            ("if !enabled {", "enabled", "enabled"),
            ("println!(\"hi\")", "println", "println"),
            ("( master)$", "master", "master"),
            ("regex foo$", "foo", "foo$"),
        ];

        for (row, click, expected) in cases {
            assert_selects(row, click, expected);
        }

        let row = "echo 你好-world done";
        assert_eq!(
            selected_word(row, col_of(row, "好") + 1).as_deref(),
            Some("你好-world")
        );
    }

    #[test]
    fn double_click_word_bounds_treat_cjk_punctuation_as_delimiters() {
        for delimiter in ['（', '）', '：', '、', '。', '，'] {
            let row = format!("left{delimiter}right");
            assert_selects(&row, "left", "left");
            assert_selects(&row, "right", "right");
            assert_selects_nothing(&row, &delimiter.to_string());
            assert_eq!(
                selected_word(&row, col_of(&row, &delimiter.to_string()) + 1),
                None,
                "second display cell of {delimiter:?} should not select"
            );
        }
    }

    #[test]
    fn double_click_word_bounds_ignore_delimiters() {
        for (row, click) in [
            (
                "tmux|newhoo|fixhoo|newmoo|notification|window_bell|herdr",
                "|",
            ),
            ("alpha,beta;gamma", ","),
            ("alpha,beta;gamma", ";"),
            ("render_status_line(app, area)", "("),
            ("render_status_line(app, area)", ")"),
            ("if !enabled {", "!"),
            ("if !enabled {", "{"),
            ("(done).", "("),
            ("(done).", "."),
        ] {
            assert_selects_nothing(row, click);
        }
    }

    #[test]
    fn link_resolution_regions_unicode_punctuation_and_explicit_links() {
        let mut terminal = crate::ghostty::Terminal::new(80, 4, 1024).unwrap();
        terminal.write("[文档](https://example.com/路径?q=a(b)), next".as_bytes());
        let regions = terminal
            .viewport_link_regions(7, 0, url_byte_range)
            .unwrap();
        assert_eq!(
            regions
                .iter()
                .map(|r| (r.row, r.start_col, r.end_col))
                .collect::<Vec<_>>(),
            vec![(0, 7, 37)]
        );
        assert!(terminal
            .viewport_link_regions(1, 0, url_byte_range)
            .unwrap()
            .is_empty());
        terminal.resize(20, 4, 0, 0).unwrap();
        assert_eq!(
            terminal
                .viewport_link_regions(9, 1, url_byte_range)
                .unwrap()
                .iter()
                .map(|r| (r.row, r.start_col, r.end_col))
                .collect::<Vec<_>>(),
            vec![(0, 7, 19), (1, 0, 17)]
        );
        for text in [
            "file:///tmp/a",
            "javascript:alert(1)",
            "\x1b]8;;https://example.com\x1b\\https://example.com\x1b]8;;\x1b\\",
        ] {
            let mut terminal = crate::ghostty::Terminal::new(80, 4, 1024).unwrap();
            terminal.write(text.as_bytes());
            assert!(terminal
                .viewport_link_regions(0, 0, url_byte_range)
                .unwrap()
                .is_empty());
        }
        let mut terminal = crate::ghostty::Terminal::new(80, 4, 1024 * 1024).unwrap();
        terminal.write(format!("https://example.com/{}", "a".repeat(9000)).as_bytes());
        assert!(terminal
            .viewport_link_regions(0, 0, url_byte_range)
            .unwrap()
            .is_empty());
    }

    #[test]
    fn link_resolution_regions_keep_grapheme_byte_offsets() {
        let mut terminal = crate::ghostty::Terminal::new(40, 3, 1024).unwrap();
        terminal.write("e\u{301}(https://example.com/路e\u{301}),".as_bytes());
        let expected = vec![crate::ghostty::LinkRegion {
            row: 0,
            start_col: 2,
            end_col: 24,
        }];
        for col in 2..=24 {
            assert_eq!(
                terminal
                    .viewport_link_regions(col, 0, url_byte_range)
                    .unwrap(),
                expected,
                "column {col}"
            );
        }
        assert!(terminal
            .viewport_link_regions(0, 0, url_byte_range)
            .unwrap()
            .is_empty());
        assert!(terminal
            .viewport_link_regions(25, 0, url_byte_range)
            .unwrap()
            .is_empty());
        terminal.resize(21, 1, 0, 0).unwrap();
        let regions = terminal
            .viewport_link_regions(1, 0, url_byte_range)
            .unwrap();
        assert_eq!(
            regions,
            vec![crate::ghostty::LinkRegion {
                row: 0,
                start_col: 0,
                end_col: 3
            }]
        );
    }

    #[test]
    fn link_resolution_regions_clip_wraps_and_wide_padding() {
        let mut terminal = crate::ghostty::Terminal::new(21, 3, 1024).unwrap();
        terminal.write("https://example.com/路径".as_bytes());
        let regions = terminal
            .viewport_link_regions(1, 1, url_byte_range)
            .unwrap();
        assert_eq!(
            regions
                .iter()
                .map(|r| (r.row, r.start_col, r.end_col))
                .collect::<Vec<_>>(),
            vec![(0, 0, 19), (1, 0, 3)]
        );
        assert!(terminal
            .viewport_link_regions(19, 2, url_byte_range)
            .unwrap()
            .is_empty());
        let mut terminal = crate::ghostty::Terminal::new(20, 2, 1024).unwrap();
        terminal.write(b"https://example.com/abcdefghijklmnopqrstuv");
        assert_eq!(
            terminal
                .viewport_link_regions(0, 0, url_byte_range)
                .unwrap()
                .iter()
                .map(|r| (r.row, r.start_col, r.end_col))
                .collect::<Vec<_>>(),
            vec![(0, 0, 19), (1, 0, 1)]
        );
        terminal.scroll_viewport_row(0);
        assert_eq!(
            terminal
                .viewport_link_regions(0, 0, url_byte_range)
                .unwrap()
                .iter()
                .map(|r| (r.row, r.start_col, r.end_col))
                .collect::<Vec<_>>(),
            vec![(0, 0, 19), (1, 0, 19)]
        );
        assert!(terminal
            .viewport_link_regions(0, 2, url_byte_range)
            .unwrap()
            .is_empty());
    }

    #[test]
    fn link_activation_resolves_full_url_with_either_end_offscreen() {
        let url = "https://example.com/abcdefghijklmnopqrstuv";
        let mut terminal = crate::ghostty::Terminal::new(20, 2, 1024 * 1024).unwrap();
        terminal.write(url.as_bytes());
        let target = terminal.viewport_link_target(0, 0).unwrap().unwrap();
        assert_eq!(url_from_link_target(target).as_deref(), Some(url));
        terminal.scroll_viewport_row(0);
        let target = terminal.viewport_link_target(5, 1).unwrap().unwrap();
        assert_eq!(url_from_link_target(target).as_deref(), Some(url));
    }

    #[test]
    fn link_activation_preserves_unicode_and_click_boundaries_after_resize() {
        let mut terminal = crate::ghostty::Terminal::new(80, 5, 1024 * 1024).unwrap();
        terminal.write("[文档](https://example.com/路径?q=a(b)), next".as_bytes());
        assert!(
            url_from_link_target(terminal.viewport_link_target(1, 0).unwrap().unwrap()).is_none()
        );
        assert_eq!(
            url_from_link_target(terminal.viewport_link_target(7, 0).unwrap().unwrap()).as_deref(),
            Some("https://example.com/路径?q=a(b)")
        );
        terminal.resize(20, 5, 0, 0).unwrap();
        assert_eq!(
            url_from_link_target(terminal.viewport_link_target(9, 1).unwrap().unwrap()).as_deref(),
            Some("https://example.com/路径?q=a(b)")
        );
        assert!(terminal.viewport_link_target(19, 4).unwrap().is_none());
    }

    #[test]
    fn link_activation_skips_wide_character_wrap_padding() {
        let url = "https://example.com/路径";
        let mut terminal = crate::ghostty::Terminal::new(20, 3, 1024).unwrap();
        terminal.write(url.as_bytes());
        for col in 0..4 {
            let target = terminal.viewport_link_target(col, 1).unwrap().unwrap();
            assert_eq!(url_from_link_target(target).as_deref(), Some(url));
        }
    }

    #[test]
    fn url_at_byte_returns_safe_visible_url_only() {
        assert_eq!(
            selected_url("see https://example.com/a(b)c.", "example"),
            Some("https://example.com/a(b)c")
        );
        assert_eq!(
            selected_url("[docs](https://example.com/docs),", "example"),
            Some("https://example.com/docs")
        );
        assert_eq!(
            selected_url("[docs](https://example.com/docs)", "docs"),
            None
        );
        assert_eq!(selected_url("open file:///tmp/report", "file"), None);
    }

    #[test]
    fn apply_workspace_git_statuses_updates_matching_workspace() {
        let mut state = app_with_workspaces(&["one", "two"]);
        let first_id = state.workspaces[0].id.clone();
        let first_cwd = state.workspaces[0].resolved_identity_cwd().unwrap();
        let second_id = state.workspaces[1].id.clone();

        let terminal_runtimes = crate::terminal::TerminalRuntimeRegistry::new();
        let changed = state.apply_workspace_git_statuses(
            &terminal_runtimes,
            vec![WorkspaceGitStatus {
                workspace_id: first_id,
                resolved_identity_cwd: first_cwd.clone(),
                status_cache_key: first_cwd,
                demand: crate::workspace::GitStatusRefreshDemand::ALL,
                auto_label: "one".into(),
                branch: Some("main".into()),
                ahead_behind: Some((2, 1)),
                space: None,
            }],
        );

        assert!(changed);
        assert_eq!(state.workspaces[0].branch().as_deref(), Some("main"));
        assert_eq!(state.workspaces[0].git_ahead_behind(), Some((2, 1)));
        assert_eq!(state.workspaces[1].id, second_id);
        assert_eq!(state.workspaces[1].git_ahead_behind(), None);
    }

    #[test]
    fn apply_workspace_git_statuses_ignores_stale_cwd() {
        let mut state = app_with_workspaces(&["one"]);
        let workspace_id = state.workspaces[0].id.clone();
        state.workspaces[0].cached_git_branch = Some("old".into());
        state.workspaces[0].cached_git_ahead_behind = Some((1, 0));

        let terminal_runtimes = crate::terminal::TerminalRuntimeRegistry::new();
        let changed = state.apply_workspace_git_statuses(
            &terminal_runtimes,
            vec![WorkspaceGitStatus {
                workspace_id,
                resolved_identity_cwd: std::path::PathBuf::from("/definitely/not/current"),
                status_cache_key: std::path::PathBuf::from("/definitely/not/current"),
                demand: crate::workspace::GitStatusRefreshDemand::ALL,
                auto_label: "stale".into(),
                branch: Some("main".into()),
                ahead_behind: Some((0, 1)),
                space: None,
            }],
        );

        assert!(!changed);
        assert_eq!(state.workspaces[0].branch().as_deref(), Some("old"));
        assert_eq!(state.workspaces[0].git_ahead_behind(), Some((1, 0)));
    }

    #[test]
    fn apply_workspace_git_statuses_ignores_unrequested_branch_changes() {
        let mut state = app_with_workspaces(&["one"]);
        let workspace_id = state.workspaces[0].id.clone();
        let cwd = state.workspaces[0].resolved_identity_cwd().unwrap();
        state.workspaces[0].cached_auto_label = "one".into();
        state.workspaces[0].cached_git_branch = Some("old".into());

        let terminal_runtimes = crate::terminal::TerminalRuntimeRegistry::new();
        let changed = state.apply_workspace_git_statuses(
            &terminal_runtimes,
            vec![WorkspaceGitStatus {
                workspace_id,
                resolved_identity_cwd: cwd.clone(),
                status_cache_key: cwd,
                demand: crate::workspace::GitStatusRefreshDemand {
                    branch: false,
                    ahead_behind: true,
                },
                auto_label: "one".into(),
                branch: Some("new".into()),
                ahead_behind: None,
                space: None,
            }],
        );

        assert!(!changed);
        assert_eq!(state.workspaces[0].branch().as_deref(), Some("old"));
    }

    #[test]
    fn apply_workspace_git_statuses_clears_missing_git_status() {
        let mut state = app_with_workspaces(&["one"]);
        let workspace_id = state.workspaces[0].id.clone();
        let cwd = state.workspaces[0].resolved_identity_cwd().unwrap();
        state.workspaces[0].cached_git_branch = Some("main".into());
        state.workspaces[0].cached_git_ahead_behind = Some((1, 2));

        let terminal_runtimes = crate::terminal::TerminalRuntimeRegistry::new();
        let changed = state.apply_workspace_git_statuses(
            &terminal_runtimes,
            vec![WorkspaceGitStatus {
                workspace_id,
                resolved_identity_cwd: cwd.clone(),
                status_cache_key: cwd,
                demand: crate::workspace::GitStatusRefreshDemand::ALL,
                auto_label: "one".into(),
                branch: None,
                ahead_behind: None,
                space: None,
            }],
        );

        assert!(changed);
        assert_eq!(state.workspaces[0].branch(), None);
        assert_eq!(state.workspaces[0].git_ahead_behind(), None);
    }

    #[test]
    fn apply_workspace_git_statuses_does_not_change_worktree_membership() {
        let mut state = app_with_workspaces(&["one"]);
        mark_linked_worktree(&mut state, 0);
        let workspace_id = state.workspaces[0].id.clone();
        let cwd = state.workspaces[0].resolved_identity_cwd().unwrap();
        let membership = state.workspaces[0].worktree_space().cloned();

        let terminal_runtimes = crate::terminal::TerminalRuntimeRegistry::new();
        let changed = state.apply_workspace_git_statuses(
            &terminal_runtimes,
            vec![WorkspaceGitStatus {
                workspace_id,
                resolved_identity_cwd: cwd.clone(),
                status_cache_key: cwd,
                demand: crate::workspace::GitStatusRefreshDemand::ALL,
                auto_label: "other".into(),
                branch: Some("scratch".into()),
                ahead_behind: None,
                space: Some(crate::workspace::GitSpaceMetadata {
                    key: "other-repo-key".into(),
                    checkout_key: "/other/checkout".into(),
                    repo_name: "other".into(),
                    repo_root: "/other/repo".into(),
                    is_linked_worktree: false,
                }),
            }],
        );

        assert!(changed);
        assert_eq!(state.workspaces[0].worktree_space().cloned(), membership);
    }

    #[test]
    fn switch_workspace_updates_active_and_selected() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);
        state.switch_workspace(2);
        assert_eq!(state.active, Some(2));
        assert_eq!(state.selected, 2);
    }

    #[test]
    fn switch_workspace_marks_panes_seen() {
        let mut state = app_with_workspaces(&["a", "b"]);
        // Mark a pane in workspace 1 as unseen
        let id = *state.workspaces[1].panes.keys().next().unwrap();
        state.workspaces[1].panes.get_mut(&id).unwrap().seen = false;

        state.switch_workspace(1);
        assert!(state.workspaces[1].panes.get(&id).unwrap().seen);
    }

    #[test]
    fn switch_workspace_out_of_bounds_is_noop() {
        let mut state = app_with_workspaces(&["a"]);
        state.switch_workspace(5);
        assert_eq!(state.active, Some(0));
    }

    #[test]
    fn move_workspace_reorders_without_changing_logical_selection() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);
        let active_id = state.workspaces[1].id.clone();
        let selected_id = state.workspaces[2].id.clone();
        state.active = Some(1);
        state.selected = 2;

        state.move_workspace(1, 0);

        let names: Vec<_> = state
            .workspaces
            .iter()
            .map(|ws| ws.display_name())
            .collect();
        assert_eq!(names, vec!["b", "a", "c"]);
        assert_eq!(state.active, Some(0));
        assert_eq!(state.selected, 2);
        assert_eq!(state.workspaces[state.active.unwrap()].id, active_id);
        assert_eq!(state.workspaces[state.selected].id, selected_id);
    }

    #[test]
    fn move_workspace_accepts_insert_at_end() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);

        state.move_workspace(0, state.workspaces.len());

        let names: Vec<_> = state
            .workspaces
            .iter()
            .map(|ws| ws.display_name())
            .collect();
        assert_eq!(names, vec!["b", "c", "a"]);
    }

    #[test]
    fn move_workspace_block_collects_non_contiguous_members() {
        let mut state =
            app_with_workspaces(&["child-one", "normal", "parent", "child-two", "tail"]);
        let parent_id = state.workspaces[2].id.clone();
        let child_one_id = state.workspaces[0].id.clone();
        let child_two_id = state.workspaces[3].id.clone();
        let tail_id = state.workspaces[4].id.clone();
        state.active = Some(0);
        state.selected = 4;

        assert!(state.move_workspace_block(
            &[parent_id, child_one_id.clone(), child_two_id],
            Some(&tail_id),
        ));

        let names = state
            .workspaces
            .iter()
            .map(|workspace| workspace.display_name())
            .collect::<Vec<_>>();
        assert_eq!(
            names,
            ["normal", "parent", "child-one", "child-two", "tail"]
        );
        assert_eq!(state.workspaces[state.active.unwrap()].id, child_one_id);
        assert_eq!(state.workspaces[state.selected].id, tail_id);
    }

    #[test]
    fn move_workspace_block_rejects_invalid_and_noop_orders() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);
        let ids = state
            .workspaces
            .iter()
            .map(|workspace| workspace.id.clone())
            .collect::<Vec<_>>();

        assert!(!state.move_workspace_block(&[], None));
        assert!(!state.move_workspace_block(&[ids[0].clone(), ids[0].clone()], None));
        assert!(!state.move_workspace_block(&["missing".into()], None));
        assert!(!state.move_workspace_block(&[ids[0].clone()], Some(&ids[0])));
        assert!(!state.move_workspace_block(&[ids[0].clone()], Some(&ids[1])));
        assert_eq!(
            state
                .workspaces
                .iter()
                .map(|workspace| workspace.display_name())
                .collect::<Vec<_>>(),
            ["a", "b", "c"]
        );
    }

    #[test]
    fn close_workspace_adjusts_indices() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);
        state.selected = 1;
        state.active = Some(1);

        state.close_selected_workspace();

        assert_eq!(state.workspaces.len(), 2);
        assert_eq!(state.selected, 1);
        assert_eq!(state.active, Some(1));
        assert_eq!(state.workspaces[1].custom_name.as_deref(), Some("c"));
    }

    #[test]
    fn close_parent_worktree_workspace_closes_group() {
        let mut state = app_with_workspaces(&["main", "issue", "notes"]);
        state.workspaces[0].worktree_space = Some(crate::workspace::WorktreeSpaceMembership {
            key: "repo-key".into(),
            label: "herdr".into(),
            repo_root: "/repo/herdr".into(),
            checkout_path: "/repo/herdr".into(),
            is_linked_worktree: false,
        });
        state.workspaces[1].worktree_space = Some(crate::workspace::WorktreeSpaceMembership {
            key: "repo-key".into(),
            label: "herdr".into(),
            repo_root: "/repo/herdr".into(),
            checkout_path: "/repo/herdr-issue".into(),
            is_linked_worktree: true,
        });
        state.selected = 0;
        state.active = Some(0);

        state.close_selected_workspace();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "notes");
        assert_eq!(state.active, Some(0));
        assert_eq!(state.selected, 0);
    }

    #[test]
    fn close_last_workspace_clears_active() {
        let mut state = app_with_workspaces(&["only"]);
        state.selected = 0;
        state.close_selected_workspace();

        assert!(state.workspaces.is_empty());
        assert_eq!(state.active, None);
        assert_eq!(state.selected, 0);
    }

    #[test]
    fn close_workspace_at_end_adjusts_selected() {
        let mut state = app_with_workspaces(&["a", "b"]);
        state.selected = 1;
        state.active = Some(1);

        state.close_selected_workspace();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.selected, 0);
        assert_eq!(state.active, Some(0));
    }

    #[test]
    fn close_non_focused_workspace_keeps_focus() {
        let mut state = app_with_workspaces(&["a", "b", "c"]);
        state.selected = 1;
        state.active = Some(0);

        state.close_selected_workspace();

        assert_eq!(state.workspaces.len(), 2);
        assert_eq!(state.workspaces[0].display_name(), "a");
        assert_eq!(state.workspaces[1].display_name(), "c");
        assert_eq!(state.selected, 0);
        assert_eq!(state.active, Some(0));
        state.assert_invariants_for_test();
    }

    #[test]
    fn pane_died_last_pane_removes_workspace() {
        let mut state = app_with_workspaces(&["a", "b"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_pane_died(pane_id);

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].custom_name.as_deref(), Some("b"));
        state.assert_invariants_for_test();
    }

    #[test]
    fn pane_died_last_workspace_enters_navigate() {
        let mut state = app_with_workspaces(&["only"]);
        state.mode = Mode::Terminal;
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_pane_died(pane_id);

        assert!(state.workspaces.is_empty());
        assert_eq!(state.mode, Mode::Navigate);
        state.assert_invariants_for_test();
    }

    #[test]
    fn pane_died_multi_pane_keeps_workspace() {
        let mut state = app_with_workspaces(&["test"]);
        let second_id = state.workspaces[0].test_split(Direction::Horizontal);
        state.ensure_test_terminals();

        state.handle_pane_died(second_id);

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].panes.len(), 1);
        state.assert_invariants_for_test();
    }

    #[test]
    fn pane_died_unknown_pane_is_noop() {
        let mut state = app_with_workspaces(&["test"]);
        let fake_id = PaneId::from_raw(9999);

        state.handle_pane_died(fake_id);

        assert_eq!(state.workspaces.len(), 1);
        state.assert_invariants_for_test();
    }
    #[test]
    fn state_changed_updates_pane() {
        let mut state = app_with_workspaces(&["test"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Working,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let terminal_id = state.workspaces[0]
            .panes
            .get(&pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        let terminal = state.terminals.get(&terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Working);
        assert_eq!(terminal.detected_agent, Some(Agent::Pi));
    }

    #[test]
    fn state_changed_idle_in_background_marks_unseen() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.active = Some(0);
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        // First set it to Working
        let bg_terminal_id = state.workspaces[1]
            .panes
            .get(&bg_pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        state.terminals.get_mut(&bg_terminal_id).unwrap().state = AgentState::Working;

        // Now transition to Idle while in background
        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let pane = state.workspaces[1].panes.get(&bg_pane_id).unwrap();
        assert!(!pane.seen);
        assert!(matches!(
            state.toast.as_ref().map(|toast| toast.kind),
            Some(ToastKind::Finished)
        ));
    }

    #[test]
    fn active_tab_completion_marks_pane_seen() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.outer_terminal_focus = Some(true);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .panes
            .get(&pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        state.terminals.get_mut(&terminal_id).unwrap().state = AgentState::Working;
        state.workspaces[0].panes.get_mut(&pane_id).unwrap().seen = false;

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let terminal = state.terminals.get(&terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Idle);
        let pane = state.workspaces[0].panes.get(&pane_id).unwrap();
        assert!(pane.seen);
    }

    #[test]
    fn initial_idle_in_background_stays_seen() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let pane = state.workspaces[1].panes.get(&bg_pane_id).unwrap();
        assert!(pane.seen);
    }

    fn assert_completion_guard_sequence(
        acquired: bool,
        states: &[AgentState],
        expect_completion: bool,
    ) {
        let mut app = app_with_workspaces(&["active", "background"]);
        app.active = Some(0);
        app.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        app.toast_config.delay_seconds = 0;
        let pane_id = app.workspaces[1].tabs[0].root_pane;
        if acquired {
            app.handle_app_event(AppEvent::AgentProcessDetected {
                pane_id,
                agent: Agent::Pi,
                observed_at: Instant::now(),
            });
        }
        for &state in states {
            app.handle_app_event(AppEvent::StateChanged {
                pane_id,
                agent: Some(Agent::Pi),
                state,
                visible_blocker: state == AgentState::Blocked,
                visible_working: state == AgentState::Working,
                process_exited: false,
                observed_at: Instant::now(),
            });
        }
        let finished = app
            .toast
            .as_ref()
            .is_some_and(|toast| toast.kind == ToastKind::Finished);
        assert_eq!(
            finished, expect_completion,
            "completion notification: {states:?}"
        );
        assert_eq!(
            !app.workspaces[1].panes[&pane_id].seen, expect_completion,
            "unseen completion: {states:?}"
        );
        let terminal = &app.terminals[&app.workspaces[1].panes[&pane_id].attached_terminal_id];
        assert_eq!(
            terminal.last_agent_completion_seq.is_some(),
            expect_completion
        );
        if expect_completion {
            assert_eq!(
                terminal.last_agent_completion_seq,
                terminal.last_agent_state_change_seq
            );
        }
        app.assert_invariants_for_test();
    }

    #[test]
    fn completion_guard_unknown_to_idle_is_not_completed_work() {
        assert_completion_guard_sequence(false, &[AgentState::Unknown, AgentState::Idle], false);
    }

    #[test]
    fn completion_guard_first_work_finishes_without_prior_idle() {
        assert_completion_guard_sequence(true, &[AgentState::Working, AgentState::Idle], true);
    }

    #[test]
    fn completion_guard_first_work_can_pause_for_permission() {
        assert_completion_guard_sequence(
            true,
            &[AgentState::Working, AgentState::Blocked, AgentState::Idle],
            true,
        );
    }

    #[test]
    fn completion_guard_startup_trust_is_not_completed_work() {
        assert_completion_guard_sequence(true, &[AgentState::Blocked, AgentState::Idle], false);
    }

    #[test]
    fn completion_guard_managed_launch_readiness_does_not_swallow_work() {
        for first_state in [AgentState::Blocked, AgentState::Working] {
            let mut app = app_with_workspaces(&["active", "background"]);
            app.active = Some(0);
            let pane_id = app.workspaces[1].tabs[0].root_pane;
            let terminal_id = app.workspaces[1].panes[&pane_id]
                .attached_terminal_id
                .clone();
            app.terminals
                .get_mut(&terminal_id)
                .unwrap()
                .begin_managed_agent(
                    "worker".into(),
                    Agent::Pi,
                    Instant::now(),
                    std::time::Duration::ZERO,
                    std::time::Duration::from_secs(60),
                );
            for state in [first_state, AgentState::Idle] {
                app.handle_app_event(AppEvent::StateChanged {
                    pane_id,
                    agent: Some(Agent::Pi),
                    state,
                    visible_blocker: state == AgentState::Blocked,
                    visible_working: state == AgentState::Working,
                    process_exited: false,
                    observed_at: Instant::now(),
                });
            }
            let terminal = &app.terminals[&terminal_id];
            assert!(terminal.managed_agent_interactive_ready());
            assert_eq!(
                terminal.last_agent_completion_seq.is_some(),
                first_state == AgentState::Working
            );
            assert_eq!(
                !app.workspaces[1].panes[&pane_id].seen,
                first_state == AgentState::Working
            );
        }
    }

    #[test]
    fn codex_prompt_observation_changes_readiness_without_completing_a_turn() {
        let mut app = app_with_workspaces(&["active", "background"]);
        let pane_id = app.workspaces[1].tabs[0].root_pane;
        let terminal_id = app.workspaces[1].panes[&pane_id]
            .attached_terminal_id
            .clone();
        app.terminals
            .get_mut(&terminal_id)
            .unwrap()
            .begin_managed_agent(
                "reviewer".into(),
                Agent::Codex,
                Instant::now(),
                std::time::Duration::ZERO,
                std::time::Duration::from_secs(60),
            );
        app.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Codex),
            state: AgentState::Unknown,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: Instant::now(),
        });
        app.handle_app_event(AppEvent::CodexPromptObserved {
            pane_id,
            ready: true,
        });
        let terminal = &app.terminals[&terminal_id];
        assert!(terminal.managed_agent_interactive_ready());
        assert_eq!(terminal.state, AgentState::Unknown);
        assert!(terminal.last_agent_completion_seq.is_none());
    }

    #[test]
    fn completion_guard_same_state_agent_replacement_clears_old_work() {
        let mut app = app_with_workspaces(&["active", "background"]);
        app.active = Some(0);
        app.toast_config.delay_seconds = 5;
        let pane_id = app.workspaces[1].tabs[0].root_pane;
        for (seq, label, state) in [
            (1, "old", AgentState::Working),
            (2, "old", AgentState::Idle),
            (3, "new", AgentState::Idle),
        ] {
            app.handle_app_event(AppEvent::HookStateReported {
                pane_id,
                source: "custom:worker".into(),
                agent_label: label.into(),
                state,
                message: None,
                seq: Some(seq),
                session_ref: None,
            });
            if seq == 2 {
                assert!(!app.workspaces[1].panes[&pane_id].seen);
                assert!(app.pending_agent_notifications.contains_key(&pane_id));
            }
        }
        let terminal = &app.terminals[&app.workspaces[1].panes[&pane_id].attached_terminal_id];
        assert_eq!(terminal.effective_agent_label(), Some("new"));
        assert!(terminal.last_agent_completion_seq.is_none());
        assert!(app.workspaces[1].panes[&pane_id].seen);
        assert!(!app.pending_agent_notifications.contains_key(&pane_id));
    }

    #[test]
    fn completion_guard_idle_session_replacement_clears_seen_and_pending_delivery() {
        let mut app = app_with_workspaces(&["active", "background"]);
        app.active = Some(0);
        app.toast_config.delay_seconds = 5;
        let pane_id = app.workspaces[1].tabs[0].root_pane;
        for (seq, session, reason) in [(1, "old-session", "startup"), (2, "new-session", "clear")] {
            let updates = app.handle_app_event(AppEvent::AgentSessionReported {
                pane_id,
                source: "herdr:claude".into(),
                agent_label: "claude".into(),
                seq: Some(seq),
                session_ref: crate::agent_resume::AgentSessionRef::id(session),
                session_start_source: Some(reason.into()),
            });
            if seq == 1 {
                for state in [AgentState::Working, AgentState::Idle] {
                    app.handle_app_event(AppEvent::StateChanged {
                        pane_id,
                        agent: Some(Agent::Claude),
                        state,
                        visible_blocker: false,
                        visible_working: state == AgentState::Working,
                        process_exited: false,
                        observed_at: Instant::now(),
                    });
                }
                assert!(!app.workspaces[1].panes[&pane_id].seen);
                assert!(app.pending_agent_notifications.contains_key(&pane_id));
            } else {
                assert!(
                    !updates.is_empty(),
                    "session replacement must publish attention reset"
                );
            }
        }
        let terminal = &app.terminals[&app.workspaces[1].panes[&pane_id].attached_terminal_id];
        assert_eq!(
            terminal
                .persisted_agent_session
                .as_ref()
                .unwrap()
                .session_ref
                .value,
            "new-session"
        );
        assert!(terminal.last_agent_completion_seq.is_none());
        assert!(app.workspaces[1].panes[&pane_id].seen);
        assert!(!app.pending_agent_notifications.contains_key(&pane_id));
    }

    #[test]
    fn completion_guard_normal_turn_still_finishes() {
        assert_completion_guard_sequence(
            true,
            &[AgentState::Idle, AgentState::Working, AgentState::Idle],
            true,
        );
    }

    #[test]
    fn first_idle_after_process_detection_is_not_completion() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.active = Some(0);
        let pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::AgentProcessDetected {
            pane_id,
            agent: Agent::Pi,
            observed_at: Instant::now(),
        });
        let direct_idle = state
            .handle_app_event(AppEvent::StateChanged {
                pane_id,
                agent: Some(Agent::Pi),
                state: AgentState::Idle,
                visible_blocker: false,
                visible_working: false,
                process_exited: false,
                observed_at: Instant::now(),
            })
            .pop()
            .expect("direct idle state update");
        assert!(direct_idle.suppress_completion);

        state.handle_app_event(AppEvent::AgentProcessDetected {
            pane_id,
            agent: Agent::Pi,
            observed_at: Instant::now(),
        });
        for agent_state in [AgentState::Working, AgentState::Blocked] {
            state.handle_app_event(AppEvent::StateChanged {
                pane_id,
                agent: Some(Agent::Pi),
                state: agent_state,
                visible_blocker: agent_state == AgentState::Blocked,
                visible_working: agent_state == AgentState::Working,
                process_exited: false,
                observed_at: Instant::now(),
            });
        }
        let update = state
            .handle_app_event(AppEvent::StateChanged {
                pane_id,
                agent: Some(Agent::Pi),
                state: AgentState::Idle,
                visible_blocker: false,
                visible_working: false,
                process_exited: false,
                observed_at: Instant::now(),
            })
            .pop()
            .expect("idle state update");

        assert!(!update.suppress_completion);
        assert!(!state.workspaces[1].panes[&pane_id].seen);
        assert!(matches!(
            state.toast.as_ref().map(|toast| toast.kind),
            Some(ToastKind::Finished)
        ));

        state.handle_app_event(AppEvent::AgentProcessDetected {
            pane_id,
            agent: Agent::Codex,
            observed_at: Instant::now(),
        });
        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Codex),
            state: AgentState::Working,
            visible_blocker: false,
            visible_working: true,
            process_exited: false,
            observed_at: Instant::now(),
        });
        let exit_update = state
            .handle_app_event(AppEvent::StateChanged {
                pane_id,
                agent: Some(Agent::Codex),
                state: AgentState::Idle,
                visible_blocker: false,
                visible_working: false,
                process_exited: true,
                observed_at: Instant::now(),
            })
            .pop()
            .expect("process exit update");
        assert!(!exit_update.suppress_completion);
    }

    #[test]
    fn waiting_sound_plays_even_in_active_workspace() {
        assert_eq!(
            notification_sound_for_state_change(true, AgentState::Working, AgentState::Blocked),
            Some(crate::sound::Sound::Request)
        );
    }

    #[test]
    fn done_sound_only_plays_in_background() {
        assert_eq!(
            notification_sound_for_state_change(false, AgentState::Working, AgentState::Idle),
            Some(crate::sound::Sound::Done)
        );
        assert_eq!(
            notification_sound_for_state_change(true, AgentState::Working, AgentState::Idle),
            None
        );
        assert_eq!(
            notification_sound_for_state_change(false, AgentState::Unknown, AgentState::Idle),
            None
        );
    }

    #[test]
    fn background_waiting_sets_attention_toast() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "pi needs attention");
        assert_eq!(toast.context, "background · 2");
    }

    #[test]
    fn delayed_background_waiting_schedules_before_toast() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.toast_config.delay_seconds = 1;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        assert!(state.toast.is_none());
        assert!(state.pending_agent_notifications.contains_key(&bg_pane_id));

        let deadline = state.next_pending_agent_notification_deadline().unwrap();
        let deliveries = state.drain_due_agent_notifications(deadline);
        assert_eq!(deliveries.len(), 1);

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "pi needs attention");
        assert_eq!(toast.context, "background · 2");
        assert!(state.pending_agent_notifications.is_empty());
    }

    #[test]
    fn delayed_background_waiting_cancels_when_agent_resumes_working() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.toast_config.delay_seconds = 1;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        let deadline = state.next_pending_agent_notification_deadline().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Working,
            visible_blocker: false,
            visible_working: true,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        assert!(state.pending_agent_notifications.is_empty());
        assert!(state.drain_due_agent_notifications(deadline).is_empty());
        assert!(state.toast.is_none());
    }

    #[test]
    fn delayed_background_waiting_is_suppressed_if_pane_becomes_active() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.toast_config.delay_seconds = 1;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        let deadline = state.next_pending_agent_notification_deadline().unwrap();
        state.active = Some(1);

        assert!(state.drain_due_agent_notifications(deadline).is_empty());
        assert!(state.toast.is_none());
    }

    #[test]
    fn delayed_active_tab_unfocused_keeps_client_notification_available() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.outer_terminal_focus = Some(false);
        state.toast_config.delivery = crate::config::ToastDelivery::System;
        state.toast_config.delay_seconds = 1;
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let deadline = state.next_pending_agent_notification_deadline().unwrap();
        let deliveries = state.drain_due_agent_notifications(deadline);

        assert_eq!(deliveries.len(), 1);
        assert!(deliveries[0].toast.is_none());
        assert!(deliveries[0].client_notification.is_some());
        assert!(state.toast.is_none());
    }

    #[test]
    fn delayed_background_waiting_is_cleared_when_pane_dies() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.toast_config.delay_seconds = 1;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        let deadline = state.next_pending_agent_notification_deadline().unwrap();
        state.handle_app_event(AppEvent::PaneDied {
            pane_id: bg_pane_id,
            exit_reason: crate::platform::ChildExitReason::Exited,
        });

        assert!(state.pending_agent_notifications.is_empty());
        assert!(state.drain_due_agent_notifications(deadline).is_empty());
        assert!(state.toast.is_none());
    }

    fn report_custom_agent_with_resume(state: &mut AppState, pane_id: PaneId, argv: &[&str]) {
        state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "prime-agent".into(),
            agent_label: "prime-agent".into(),
            state: AgentState::Idle,
            message: None,
            seq: Some(1),
            session_ref: None,
        });
        state.handle_app_event(AppEvent::AgentResumeReported {
            pane_id,
            source: "prime-agent".into(),
            agent_label: "prime-agent".into(),
            seq: Some(1),
            argv: argv.iter().map(|part| part.to_string()).collect(),
        });
    }

    fn first_pane_terminal(state: &AppState) -> (PaneId, crate::terminal::TerminalId) {
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0].panes[&pane_id]
            .attached_terminal_id
            .clone();
        (pane_id, terminal_id)
    }

    #[test]
    fn reported_resume_follows_the_reporting_agent_until_release() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        report_custom_agent_with_resume(&mut state, pane_id, &["prime-agent", "--resume", "a"]);

        let resume = state.terminals[&terminal_id].reported_resume().unwrap();
        assert_eq!(resume.agent, "prime-agent");
        assert_eq!(resume.argv, vec!["prime-agent", "--resume", "a"]);

        state.handle_app_event(AppEvent::AgentResumeReported {
            pane_id,
            source: "someone-else".into(),
            agent_label: "other".into(),
            seq: None,
            argv: vec!["other".into()],
        });
        assert_eq!(
            state.terminals[&terminal_id]
                .reported_resume()
                .unwrap()
                .argv,
            vec!["prime-agent", "--resume", "a"]
        );

        state.handle_app_event(AppEvent::HookAgentReleased {
            pane_id,
            source: "prime-agent".into(),
            agent_label: "prime-agent".into(),
            known_agent: None,
            seq: Some(2),
        });
        assert!(state.terminals[&terminal_id].reported_resume().is_none());
    }

    #[test]
    fn reported_resume_is_dropped_and_saved_when_another_agent_takes_the_pane() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        report_custom_agent_with_resume(&mut state, pane_id, &["prime-agent", "--resume", "a"]);
        state.session_dirty = false;

        state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "custom:other".into(),
            agent_label: "other".into(),
            state: AgentState::Working,
            message: None,
            seq: None,
            session_ref: None,
        });

        assert!(state.terminals[&terminal_id].reported_resume().is_none());
        assert!(state.session_dirty);
    }

    #[test]
    fn reported_resume_of_recognized_agent_is_dropped_when_its_process_exits() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        state.handle_app_event(AppEvent::AgentProcessDetected {
            pane_id,
            agent: Agent::Pi,
            observed_at: std::time::Instant::now(),
        });
        state.handle_app_event(AppEvent::AgentResumeReported {
            pane_id,
            source: "herdr:pi".into(),
            agent_label: "pi".into(),
            seq: None,
            argv: vec!["pi".into(), "--continue".into()],
        });
        assert!(state.terminals[&terminal_id].reported_resume().is_some());
        state.session_dirty = false;

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: true,
            observed_at: std::time::Instant::now(),
        });

        assert!(state.terminals[&terminal_id].reported_resume().is_none());
        assert!(state.session_dirty);

        state.handle_app_event(AppEvent::AgentResumeReported {
            pane_id,
            source: "herdr:pi".into(),
            agent_label: "pi".into(),
            seq: None,
            argv: vec!["pi".into(), "--continue".into()],
        });
        assert!(
            state.terminals[&terminal_id].reported_resume().is_none(),
            "a late report must not revive an exited agent"
        );
    }

    #[test]
    fn shell_return_drops_self_reported_agent_and_its_resume() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        report_custom_agent_with_resume(&mut state, pane_id, &["prime-agent", "--resume", "a"]);
        assert!(state.terminals[&terminal_id].self_reported_agent_active());

        state.handle_app_event(AppEvent::ReportedAgentShellReturned {
            pane_id,
            observed_at: std::time::Instant::now(),
        });

        let terminal = &state.terminals[&terminal_id];
        assert_eq!(terminal.effective_agent_label(), None);
        assert!(terminal.reported_resume().is_none());
        assert!(!terminal.self_reported_agent_active());
    }

    #[test]
    fn delayed_shell_return_keeps_an_agent_that_claimed_the_pane_afterwards() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        let shell_seen_idle_at = std::time::Instant::now();
        report_custom_agent_with_resume(&mut state, pane_id, &["prime-agent", "--resume", "b"]);

        state.handle_app_event(AppEvent::ReportedAgentShellReturned {
            pane_id,
            observed_at: shell_seen_idle_at,
        });

        let terminal = &state.terminals[&terminal_id];
        assert_eq!(terminal.effective_agent_label(), Some("prime-agent"));
        assert!(terminal.reported_resume().is_some());
    }

    #[test]
    fn shell_return_keeps_agents_herdr_recognizes_by_process() {
        let mut state = app_with_workspaces(&["one"]);
        let (pane_id, terminal_id) = first_pane_terminal(&state);
        state.handle_app_event(AppEvent::AgentProcessDetected {
            pane_id,
            agent: Agent::Pi,
            observed_at: std::time::Instant::now(),
        });
        state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "herdr:pi".into(),
            agent_label: "pi".into(),
            state: AgentState::Working,
            message: None,
            seq: Some(1),
            session_ref: None,
        });
        assert!(!state.terminals[&terminal_id].self_reported_agent_active());

        state.handle_app_event(AppEvent::ReportedAgentShellReturned {
            pane_id,
            observed_at: std::time::Instant::now(),
        });

        assert_eq!(
            state.terminals[&terminal_id].effective_agent_label(),
            Some("pi")
        );
    }

    #[test]
    fn hook_reported_unknown_agent_sets_toast_title_from_label() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::HookStateReported {
            pane_id: bg_pane_id,
            source: "custom:hermes".into(),
            agent_label: "hermes".into(),
            state: AgentState::Blocked,
            message: None,
            seq: None,
            session_ref: None,
        });

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "hermes needs attention");
        assert_eq!(toast.context, "background · 2");
    }

    #[test]
    fn visible_blocker_overrides_hook_working_and_notifies() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();
        let bg_terminal_id = state.workspaces[1]
            .panes
            .get(&bg_pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Codex),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        state.handle_app_event(AppEvent::HookStateReported {
            pane_id: bg_pane_id,
            source: "herdr:codex".into(),
            agent_label: "codex".into(),
            state: AgentState::Working,
            message: None,
            seq: Some(1),
            session_ref: None,
        });
        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Codex),
            state: AgentState::Blocked,
            visible_blocker: true,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let terminal = state.terminals.get(&bg_terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Blocked);
        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "codex needs attention");
    }

    #[test]
    fn reserved_native_state_report_does_not_override_screen_state() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .panes
            .get(&pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Claude),
            state: AgentState::Working,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "herdr:claude".into(),
            agent_label: "claude".into(),
            state: AgentState::Blocked,
            message: None,
            seq: Some(1),
            session_ref: crate::agent_resume::AgentSessionRef::id("claude-session"),
        });
        let terminal = state.terminals.get(&terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Working);
        assert!(terminal.hook_authority.is_none());
        assert!(terminal.persisted_agent_session.is_some());

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Claude),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let terminal = state.terminals.get(&terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Idle);
        assert!(state.toast.is_none());
    }

    #[test]
    fn official_release_preserves_process_owned_agent_identity() {
        let mut state = app_with_workspaces(&["active"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .panes
            .get(&pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Working,
            visible_blocker: false,
            visible_working: true,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        let terminal = state.terminals.get_mut(&terminal_id).unwrap();
        terminal.set_persisted_agent_session(crate::agent_resume::PersistedAgentSession {
            source: "herdr:pi".into(),
            agent: "pi".into(),
            session_ref: crate::agent_resume::AgentSessionRef::path(
                std::env::current_dir()
                    .unwrap()
                    .join("release-session.jsonl")
                    .display()
                    .to_string(),
            )
            .unwrap(),
        });
        terminal.set_hook_authority(
            "herdr:pi".into(),
            "pi".into(),
            AgentState::Working,
            None,
            Some(1),
        );
        terminal.set_agent_name("reviewer".into());
        state.session_dirty = false;

        let updates = state.handle_app_event(AppEvent::HookAgentReleased {
            pane_id,
            source: "herdr:pi".into(),
            agent_label: "pi".into(),
            known_agent: Some(Agent::Pi),
            seq: Some(2),
        });

        assert!(updates.is_empty());
        let terminal = &state.terminals[&terminal_id];
        assert_eq!(terminal.state, AgentState::Working);
        assert_eq!(terminal.detected_agent, Some(Agent::Pi));
        assert_eq!(terminal.agent_name.as_deref(), Some("reviewer"));
        assert!(terminal.full_lifecycle_hook_authority_active());
        assert!(!state.session_dirty);
    }

    #[test]
    fn devin_state_report_refreshes_session_without_overriding_screen_state() {
        let mut state = app_with_workspaces(&["active"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .panes
            .get(&pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Devin),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });
        state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "herdr:devin".into(),
            agent_label: "devin".into(),
            state: AgentState::Working,
            message: None,
            seq: Some(1),
            session_ref: crate::agent_resume::AgentSessionRef::id("devin-session"),
        });

        let terminal = state.terminals.get(&terminal_id).unwrap();
        assert_eq!(terminal.state, AgentState::Idle);
        assert!(terminal.hook_authority.is_none());
        assert!(terminal.persisted_agent_session.is_some());
    }

    #[test]
    fn hidden_custom_session_ref_only_update_marks_session_dirty_without_visible_update() {
        let mut state = app_with_workspaces(&["active"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let test_dir = std::env::current_dir().unwrap();
        let first_session = test_dir.join("one.jsonl").display().to_string();
        let second_session = test_dir.join("two.jsonl").display().to_string();

        let first_updates = state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "custom:pi".into(),
            agent_label: "pi".into(),
            state: AgentState::Working,
            message: None,
            seq: Some(20),
            session_ref: crate::agent_resume::AgentSessionRef::path(first_session),
        });
        assert_eq!(first_updates.len(), 1);
        state.session_dirty = false;

        let second_updates = state.handle_app_event(AppEvent::HookStateReported {
            pane_id,
            source: "custom:pi".into(),
            agent_label: "pi".into(),
            state: AgentState::Working,
            message: None,
            seq: Some(21),
            session_ref: crate::agent_resume::AgentSessionRef::path(second_session),
        });

        assert!(second_updates.is_empty());
        assert!(state.session_dirty);
    }

    #[test]
    fn custom_release_clears_report_owned_agent() {
        let mut state = app_with_workspaces(&["active"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .pane_state(pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        state
            .terminals
            .get_mut(&terminal_id)
            .unwrap()
            .set_hook_authority(
                "custom:agent".into(),
                "custom-agent".into(),
                AgentState::Working,
                None,
                Some(1),
            );

        state.handle_app_event(AppEvent::HookAgentReleased {
            pane_id,
            source: "custom:agent".into(),
            agent_label: "custom-agent".into(),
            known_agent: None,
            seq: Some(2),
        });

        let terminal = &state.terminals[&terminal_id];
        assert!(terminal.hook_authority.is_none());
        assert_eq!(terminal.state, AgentState::Unknown);
    }

    #[test]
    fn terminal_cwd_report_updates_terminal_cwd_and_marks_session_dirty() {
        let mut state = app_with_workspaces(&["active"]);
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();
        let terminal_id = state.workspaces[0]
            .pane_state(pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        let cwd =
            std::env::temp_dir().join(format!("herdr-cwd-report-test-{}", std::process::id()));
        std::fs::create_dir_all(&cwd).unwrap();
        state.session_dirty = false;

        let updates = state.handle_app_event(AppEvent::TerminalCwdReported {
            pane_id,
            cwd: cwd.clone(),
        });

        assert!(updates.is_empty());
        assert_eq!(state.terminals.get(&terminal_id).unwrap().cwd, cwd);
        assert!(state.session_dirty);
        let _ = std::fs::remove_dir_all(cwd);
    }

    #[test]
    fn background_idle_sets_finished_toast() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let bg_pane_id = *state.workspaces[1].panes.keys().next().unwrap();
        let bg_terminal_id = state.workspaces[1]
            .panes
            .get(&bg_pane_id)
            .unwrap()
            .attached_terminal_id
            .clone();
        state.terminals.get_mut(&bg_terminal_id).unwrap().state = AgentState::Working;

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Droid),
            state: AgentState::Idle,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::Finished);
        assert_eq!(toast.title, "droid finished");
        assert_eq!(toast.context, "background · 2");
        let target = toast.target.as_ref().expect("toast target");
        assert_eq!(&target.workspace_id, &state.workspaces[1].id);
        assert_eq!(target.pane_id, bg_pane_id);
    }

    #[test]
    fn background_toast_includes_tab_name_when_workspace_has_multiple_tabs() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.workspaces[1].tabs[0].set_custom_name("main".into());
        let second_tab = state.workspaces[1].test_add_tab(Some("logs"));
        state.ensure_test_terminals();
        let bg_pane_id = state.workspaces[1].tabs[second_tab].root_pane;

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "pi needs attention");
        assert_eq!(toast.context, "background · 2 · logs");
    }

    #[test]
    fn background_tab_in_active_workspace_still_sets_toast() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.workspaces[0].tabs[0].set_custom_name("main".into());
        let second_tab = state.workspaces[0].test_add_tab(Some("logs"));
        state.ensure_test_terminals();
        let bg_pane_id = state.workspaces[0].tabs[second_tab].root_pane;

        state.handle_app_event(AppEvent::StateChanged {
            pane_id: bg_pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        let toast = state.toast.as_ref().unwrap();
        assert_eq!(toast.kind, ToastKind::NeedsAttention);
        assert_eq!(toast.title, "pi needs attention");
        assert_eq!(toast.context, "active · 1 · logs");
    }

    #[test]
    fn active_workspace_active_tab_does_not_set_toast() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        assert!(state.toast.is_none());
    }

    #[test]
    fn active_workspace_active_tab_keeps_herdr_toast_suppressed_when_outer_terminal_is_unfocused() {
        let mut state = app_with_workspaces(&["active"]);
        state.active = Some(0);
        state.outer_terminal_focus = Some(false);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let pane_id = *state.workspaces[0].panes.keys().next().unwrap();

        state.handle_app_event(AppEvent::StateChanged {
            pane_id,
            agent: Some(Agent::Pi),
            state: AgentState::Blocked,
            visible_blocker: false,
            visible_working: false,
            process_exited: false,
            observed_at: std::time::Instant::now(),
        });

        assert!(state.toast.is_none());
    }

    #[test]
    fn active_tab_suppression_preserves_unknown_focus_behavior() {
        assert!(active_tab_suppresses_notifications(true, None));
        assert!(active_tab_suppresses_notifications(true, Some(true)));
        assert!(!active_tab_suppresses_notifications(true, Some(false)));
        assert!(!active_tab_suppresses_notifications(false, None));
    }

    #[test]
    fn update_ready_sets_manual_update_toast() {
        let mut state = AppState::test_new();
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;

        let updates = state.handle_app_event(AppEvent::UpdateReady {
            version: "0.5.0".into(),
            install_command: "herdr update".into(),
        });

        assert!(updates.is_empty());
        assert_eq!(state.update_available.as_deref(), Some("0.5.0"));
        assert!(state.latest_release_notes_available);
        assert!(state.update_dismissed);
        let toast = state.toast.as_ref().expect("update toast");
        assert_eq!(toast.kind, ToastKind::UpdateInstalled);
        assert_eq!(toast.title, "v0.5.0 available");
        assert_eq!(
            toast.context,
            "detach, run `herdr update`, then run Herdr again to reconnect"
        );
    }

    #[test]
    fn update_ready_uses_event_install_command_in_toast() {
        let mut state = AppState::test_new();
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;

        state.handle_app_event(AppEvent::UpdateReady {
            version: "0.5.0".into(),
            install_command: "brew update && brew upgrade herdr".into(),
        });

        assert_eq!(
            state.update_install_command,
            "brew update && brew upgrade herdr"
        );
        let toast = state.toast.as_ref().expect("update toast");
        assert_eq!(
            toast.context,
            "detach, run `brew update && brew upgrade herdr`, then run Herdr again to reconnect"
        );
    }

    #[test]
    fn agent_detection_manifest_update_event_updates_status_and_toast() {
        let mut state = AppState::test_new();
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        let status = crate::detect::manifest_update::ManifestUpdateStatus {
            last_result: Some("checked".to_string()),
            ..Default::default()
        };

        let updates = state.handle_app_event(AppEvent::AgentDetectionManifestsUpdated {
            updated: vec![crate::detect::manifest_update::ManifestUpdateCommit {
                agent: Agent::Codex,
                version: crate::detect::manifest_update::ManifestVersion::parse("2026.06.10.1")
                    .unwrap(),
            }],
            activated: Vec::new(),
            status,
        });

        assert!(updates.is_empty());
        assert_eq!(
            state.agent_manifest_update_status.last_result.as_deref(),
            Some("checked")
        );
        let toast = state.toast.as_ref().expect("manifest update toast");
        assert_eq!(toast.kind, ToastKind::UpdateInstalled);
        assert_eq!(toast.title, "Agent detection rules updated");
        assert_eq!(toast.context, "codex 2026.06.10.1");
    }

    #[test]
    fn toggle_zoom_works() {
        let mut state = app_with_workspaces(&["test"]);
        state.workspaces[0].test_split(Direction::Horizontal);

        assert!(!state.workspaces[0].zoomed);
        state.toggle_zoom();
        assert!(state.workspaces[0].zoomed);
        state.toggle_zoom();
        assert!(!state.workspaces[0].zoomed);
    }

    #[test]
    fn toggle_zoom_single_pane_noop() {
        let mut state = app_with_workspaces(&["test"]);
        state.toggle_zoom();
        assert!(!state.workspaces[0].zoomed);
    }

    #[test]
    fn navigate_pane_changes_focus_while_zoomed() {
        let mut state = app_with_workspaces(&["test"]);
        let root = state.workspaces[0].tabs[0].root_pane;
        let right = state.workspaces[0].test_split(Direction::Horizontal);
        state.workspaces[0].layout.focus_pane(root);
        state.workspaces[0].zoomed = true;
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );

        assert_eq!(state.view.pane_infos.len(), 1);
        assert_eq!(state.view.pane_infos[0].id, root);

        state.navigate_pane(NavDirection::Right);
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );

        assert!(state.workspaces[0].zoomed);
        assert_eq!(state.workspaces[0].focused_pane_id(), Some(right));
        assert_eq!(state.view.pane_infos.len(), 1);
        assert_eq!(state.view.pane_infos[0].id, right);
        assert!(state.view.pane_infos[0].inner_rect.x > state.view.pane_infos[0].rect.x);
    }

    #[test]
    fn swap_pane_direction_preserves_focus_and_swaps_layout_cells() {
        let mut state = app_with_workspaces(&["test"]);
        let root = state.workspaces[0].tabs[0].root_pane;
        let right = state.workspaces[0].test_split(Direction::Horizontal);
        state.workspaces[0].layout.focus_pane(root);
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );
        let before_root_rect = state
            .view
            .pane_infos
            .iter()
            .find(|info| info.id == root)
            .unwrap()
            .rect;
        let before_right_rect = state
            .view
            .pane_infos
            .iter()
            .find(|info| info.id == right)
            .unwrap()
            .rect;

        assert!(state.swap_pane(NavDirection::Right));
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );

        assert_eq!(state.workspaces[0].focused_pane_id(), Some(root));
        assert_eq!(
            state
                .view
                .pane_infos
                .iter()
                .find(|info| info.id == root)
                .unwrap()
                .rect,
            before_right_rect
        );
        assert_eq!(
            state
                .view
                .pane_infos
                .iter()
                .find(|info| info.id == right)
                .unwrap()
                .rect,
            before_root_rect
        );
    }

    #[test]
    fn swap_pane_direction_stays_zoomed_and_mutates_hidden_layout() {
        let mut state = app_with_workspaces(&["test"]);
        let root = state.workspaces[0].tabs[0].root_pane;
        let right = state.workspaces[0].test_split(Direction::Horizontal);
        state.workspaces[0].layout.focus_pane(root);
        state.workspaces[0].zoomed = true;
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );

        assert!(state.swap_pane(NavDirection::Right));
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );

        assert!(state.workspaces[0].zoomed);
        assert_eq!(state.workspaces[0].focused_pane_id(), Some(root));
        assert_eq!(state.view.pane_infos.len(), 1);
        assert_eq!(state.view.pane_infos[0].id, root);

        state.workspaces[0].zoomed = false;
        crate::ui::compute_view_with_runtime_registry(
            &mut state,
            &crate::terminal::TerminalRuntimeRegistry::new(),
            ratatui::layout::Rect::new(0, 0, 100, 20),
        );
        let root_rect = state
            .view
            .pane_infos
            .iter()
            .find(|info| info.id == root)
            .unwrap()
            .rect;
        let right_rect = state
            .view
            .pane_infos
            .iter()
            .find(|info| info.id == right)
            .unwrap()
            .rect;

        assert!(root_rect.x > right_rect.x);
    }

    #[test]
    fn close_pane_removes_from_workspace() {
        let mut state = app_with_workspaces(&["test"]);
        let closed = state.workspaces[0].test_split(Direction::Horizontal);
        state.ensure_test_terminals();
        assert_eq!(state.workspaces[0].panes.len(), 2);
        state.plugin_panes.insert(
            closed,
            crate::app::state::PluginPaneRecord {
                plugin_id: "example.pane".into(),
                entrypoint: "board".into(),
            },
        );
        state.close_pane();
        assert_eq!(state.workspaces[0].panes.len(), 1);
        assert!(!state.plugin_panes.contains_key(&closed));
        state.assert_invariants_for_test();
    }

    #[test]
    fn pane_process_exit_publish_marks_agent_idle_before_pane_removal() {
        let mut state = app_with_workspaces(&["active", "background"]);
        state.toast_config.delivery = crate::config::ToastDelivery::Herdr;
        state.active = Some(1);
        state.ensure_test_terminals();
        let pane_id = state.workspaces[0].tabs[0].root_pane;
        let terminal_id = state.terminal_id_for_pane(0, pane_id).unwrap();
        state
            .terminals
            .get_mut(&terminal_id)
            .unwrap()
            .set_detected_state(Some(Agent::Pi), AgentState::Working);
        assert_eq!(
            state.terminals.get(&terminal_id).unwrap().state,
            AgentState::Working
        );

        let update = state
            .publish_pane_process_exit_if_agent(pane_id, false)
            .expect("process exit update");

        assert!(!state.pane_is_in_active_tab(update.ws_idx, pane_id));
        assert_eq!(update.previous_state, AgentState::Working);
        assert_eq!(update.state, AgentState::Idle);
        assert_eq!(update.agent_label.as_deref(), Some("pi"));
        assert_eq!(update.known_agent, Some(Agent::Pi));
        assert!(update.agent_released);
        assert_eq!(
            update.agent_release_status,
            Some(crate::api::schema::AgentStatus::Done)
        );
        assert!(matches!(
            state.toast.as_ref().map(|toast| toast.kind),
            Some(ToastKind::Finished)
        ));
    }

    #[test]
    fn close_pane_removes_unattached_terminal_state() {
        let mut state = app_with_workspaces(&["test"]);
        let pane_id = state.workspaces[0].test_split(Direction::Horizontal);
        state.ensure_test_terminals();
        let terminal_id = state.terminal_id_for_pane(0, pane_id).unwrap();

        state.close_pane();

        assert!(!state.terminals.contains_key(&terminal_id));
        state.assert_invariants_for_test();
    }

    #[test]
    fn close_tab_removes_unattached_terminal_states() {
        let mut state = app_with_workspaces(&["test"]);
        let tab_idx = state.workspaces[0].test_add_tab(Some("logs"));
        state.ensure_test_terminals();
        state.workspaces[0].switch_tab(tab_idx);
        let pane_id = state.workspaces[0].tabs[tab_idx].root_pane;
        let terminal_id = state.terminal_id_for_pane(0, pane_id).unwrap();
        state.plugin_panes.insert(
            pane_id,
            crate::app::state::PluginPaneRecord {
                plugin_id: "example.pane".into(),
                entrypoint: "board".into(),
            },
        );
        state.close_tab();

        assert!(!state.terminals.contains_key(&terminal_id));
        assert!(!state.plugin_panes.contains_key(&pane_id));
        state.assert_invariants_for_test();
    }

    #[test]
    fn close_workspace_removes_unattached_terminal_states() {
        let mut state = app_with_workspaces(&["one", "two"]);
        let pane_id = state.workspaces[0].tabs[0].root_pane;
        let terminal_id = state.terminal_id_for_pane(0, pane_id).unwrap();
        state.plugin_panes.insert(
            pane_id,
            crate::app::state::PluginPaneRecord {
                plugin_id: "example.pane".into(),
                entrypoint: "board".into(),
            },
        );
        state.close_selected_workspace();

        assert!(!state.terminals.contains_key(&terminal_id));
        assert!(!state.plugin_panes.contains_key(&pane_id));
        state.assert_invariants_for_test();
    }

    #[test]
    fn close_tab_closes_active_workspace_not_selected_workspace() {
        let mut state = app_with_workspaces(&["selected", "active"]);
        let active_terminal_id = state
            .terminal_id_for_pane(1, state.workspaces[1].tabs[0].root_pane)
            .unwrap();
        state.active = Some(1);
        state.selected = 0;

        state.close_tab();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "selected");
        assert!(!state.terminals.contains_key(&active_terminal_id));
        state.assert_invariants_for_test();
    }

    #[test]
    fn close_pane_last_pane_closes_active_workspace_not_selected_workspace() {
        let mut state = app_with_workspaces(&["selected", "active"]);
        let active_terminal_id = state
            .terminal_id_for_pane(1, state.workspaces[1].tabs[0].root_pane)
            .unwrap();
        state.active = Some(1);
        state.selected = 0;

        state.close_pane();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "selected");
        assert!(!state.terminals.contains_key(&active_terminal_id));
        state.assert_invariants_for_test();
    }

    #[test]
    fn close_pane_last_pane_in_parent_worktree_group_prompts() {
        let mut state = app_with_workspaces(&["parent", "child"]);
        mark_parent_worktree(&mut state, 0);
        mark_linked_worktree(&mut state, 1);
        state.active = Some(0);
        state.selected = 1;

        let deferred = state.close_pane();

        assert!(deferred);
        assert_eq!(state.selected, 1);
        assert_eq!(state.workspaces.len(), 2);
    }

    #[test]
    fn close_tab_in_linked_worktree_closes_workspace_only() {
        let mut state = app_with_workspaces(&["selected", "active"]);
        mark_linked_worktree(&mut state, 1);
        state.active = Some(1);
        state.selected = 0;

        state.close_tab();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "selected");
    }

    #[test]
    fn close_tab_last_tab_in_parent_worktree_group_prompts() {
        let mut state = app_with_workspaces(&["parent", "child"]);
        mark_parent_worktree(&mut state, 0);
        mark_linked_worktree(&mut state, 1);
        state.active = Some(0);
        state.selected = 1;

        let deferred = state.close_tab();

        assert!(deferred);
        assert_eq!(state.selected, 1);
        assert_eq!(state.workspaces.len(), 2);
    }

    #[test]
    fn close_pane_last_pane_in_linked_worktree_closes_workspace_only() {
        let mut state = app_with_workspaces(&["selected", "active"]);
        mark_linked_worktree(&mut state, 1);
        state.active = Some(1);
        state.selected = 0;

        state.close_pane();

        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "selected");
    }

    #[test]
    fn close_pane_last_pane_in_parent_worktree_group_closes_when_confirmation_disabled() {
        let mut state = app_with_workspaces(&["parent", "child", "notes"]);
        mark_parent_worktree(&mut state, 0);
        mark_linked_worktree(&mut state, 1);
        state.confirm_close = false;
        state.active = Some(0);
        state.selected = 0;

        let deferred = state.close_pane();

        assert!(!deferred);
        assert_eq!(state.workspaces.len(), 1);
        assert_eq!(state.workspaces[0].display_name(), "notes");
    }
}