tix-tracker 0.11.0

//! The `F10` **Portfolio** page's **Roadmap** tab (WP05): the shared
//! [`RoadmapProjection`] the CLI renders, as a tab on the page `#1593` gives the
//! project registry.
//!
//! # A tab, not a mode
//!
//! The mission's earlier planning sketch described the roadmap as a top-level
//! page; the surface that actually shipped is an **additional tab on the `F10`
//! Portfolio page** (`switch_to_portfolio`), exactly as the Epics tab is. So there
//! is no new function key, no new [`crate::keybindings::InputContext`] and no new
//! `TopMode`: `Tab`/`Shift+Tab` cycle `Projects -> Epics -> Roadmap`, `j`/`k` walk
//! the rows, and `q`/`esc` close the page. `F9` stays reserved for `#1593`'s Data
//! page.
//!
//! # Exactly the CLI's rows
//!
//! Nothing here re-renders a figure. The list headline and the detail pane are the
//! CLI's own [`crate::commands::roadmap::roadmap_row_lines`] (the same lines
//! `tix roadmap show` prints, contributions and diagnostics included), the empty
//! state is [`crate::commands::roadmap::roadmap_list_lines`]'s own sentence, and
//! the active criteria line is
//! [`crate::commands::roadmap::roadmap_filter_line`]. The projection itself is the
//! shared [`crate::roadmap::projection::project`] over a once-per-refresh source
//! snapshot ([`projection_over`]); this module owns no progress, risk or ownership
//! rule, so the tab cannot disagree with the CLI about one (C-004, C-007).
//!
//! # Filters are the one DTO
//!
//! The filter editor ([`RoadmapOverlay::Filter`]) edits a [`FilterDraft`] and
//! normalizes it into the **same** [`RoadmapFilter`] the CLI builds; the predicate
//! and the ordering stay in [`crate::roadmap`]. There is no second filter grammar.
//!
//! # Actions go through the registry
//!
//! `c`/`e`/`a`/`x` open the create, rename, associate and dereference overlays.
//! Applying one calls [`crate::roadmap::registry`]'s own atomic boundary with the
//! live `tix.toml` path — the same writer `tix initiative …` uses — so a refusal
//! leaves the file byte-identical and no second writer exists (C-008).

use std::collections::HashSet;

use ratatui::Frame;
use ratatui::layout::{Constraint, Direction, Layout, Rect};
use ratatui::style::{Color, Modifier, Style};
use ratatui::text::{Line, Span};
use ratatui::widgets::{Block, Borders, Clear, Paragraph, Wrap};

use crate::app::App;
use crate::config::Config;
use crate::error::Result;
use crate::model::Issue;
use crate::roadmap::registry::{AssociationKind, InitiativeEdit, NewInitiative};
use crate::roadmap::{
    RoadmapConsumed, RoadmapFilter, RoadmapProjection, RoadmapRow, RoadmapSources,
};
use crate::storage::Store;

// ---------------------------------------------------------------------------
// Tab registration (read by `crate::ui::portfolio`)
// ---------------------------------------------------------------------------

/// The tab's label in the Portfolio strip.
pub const TAB_LABEL: &str = "Roadmap";

/// The registry the tab reads, as `tix.toml` spells it.
///
/// The roadmap is a **projection** over `[initiatives.<id>]`, so this names the
/// section the tab's data is declared in rather than a section of its own.
pub const TAB_SECTION: &str = "initiatives";

/// The tab's noun, for a detail pane with nothing to describe.
pub const TAB_NOUN: &str = "initiative";

/// What to say when the initiative registry is empty.
pub const TAB_EMPTY_HINT: &str =
    "No initiatives yet — run `tix initiative create <name>`, or press `c` to add one here.";

/// The one-line hint under the strip: the tab's keys, matching what the handler
/// reads.
pub const TAB_HINT: &str =
    "j/k row · c create · e rename · a associate · x dereference · f filter · Tab tabs · q close";

// ---------------------------------------------------------------------------
// The read adapter (T022)
// ---------------------------------------------------------------------------

/// The shared projection for `filter`, over an already-read issue snapshot.
///
/// This is the TUI's counterpart of the CLI's `build_sources` + `projection::project`
/// pair: the **consumed** facts (assigned, overdue, blocked, reference targets) are
/// gathered from their owning services — never derived here — and the join, the
/// predicate and the sort all stay in [`crate::roadmap`]. `issues` is passed in so
/// the page can reuse the `store.list_all()` read it already made for the Projects
/// and Epics tabs instead of reading the tree a second time (NFR-001).
pub fn projection_over(
    config: &Config,
    store: &Store,
    issues: &[Issue],
    filter: &RoadmapFilter,
) -> Result<RoadmapProjection> {
    filter.validate()?;
    let policy = config.health.policy()?;
    let root = Config::project_root(&store.issues_dir).unwrap_or_else(|| store.issues_dir.clone());
    let planner = crate::planning::Planner::from_config(config.clone(), root);
    let targets = crate::epics::ReferenceTargets::from_planner(&planner)?;
    let overdue: HashSet<u32> = planner
        .overdue_batch(store, &crate::model::today())
        .iter()
        .map(|issue| issue.number)
        .collect();
    let assigned = crate::projects::assigned_keys(issues);
    let (graph_issues, done_column) = store.graph_source()?;
    let views: Vec<crate::relationships::IssueView<'_>> =
        graph_issues.iter().map(Issue::issue_view).collect();
    let graph = crate::relationships::RelationshipGraph::new(&views, &done_column);
    let blocked: HashSet<u32> = graph_issues
        .iter()
        .filter(|issue| graph.blocked_state(issue.number).is_blocked)
        .map(|issue| issue.number)
        .collect();
    let consumed = RoadmapConsumed {
        targets,
        done_column,
        assigned,
        overdue,
        blocked,
    };
    let sources = RoadmapSources::new(config, issues, &policy, consumed);
    crate::roadmap::projection::project(config, &sources, filter)
}

// ---------------------------------------------------------------------------
// Pure render data (T022, T025)
// ---------------------------------------------------------------------------

/// One row's headline: the **CLI's own** header line, its tab separators spaced so
/// the TUI list reads as columns.
///
/// The content is [`crate::commands::roadmap::roadmap_row_lines`]'s first line
/// verbatim (`id`, name, target date or `undated`, summary state); replacing the
/// separator with spaces is presentation only.
#[must_use]
pub fn headline(row: &RoadmapRow) -> String {
    crate::commands::roadmap::roadmap_row_lines(row)
        .into_iter()
        .next()
        .unwrap_or_default()
        .replace('\t', "  ")
}

/// One row's detail lines: the CLI's `roadmap show` output, **verbatim**.
///
/// Every provenance, resolution (`[missing]`), progress, risk, policy version,
/// empty-summary sentence and diagnostic the CLI prints is here, because it is the
/// CLI's string.
#[must_use]
pub fn detail_lines(row: &RoadmapRow) -> Vec<String> {
    crate::commands::roadmap::roadmap_row_lines(row)
}

/// The CLI's explicit empty state for a projection that selected nothing.
#[must_use]
pub fn empty_state_lines(projection: &RoadmapProjection) -> Vec<String> {
    crate::commands::roadmap::roadmap_list_lines(projection)
}

/// The active normalized criteria, exactly as `tix roadmap list` prints them, or
/// `None` when the filter narrows nothing.
#[must_use]
pub fn filter_context(filter: &RoadmapFilter) -> Option<String> {
    crate::commands::roadmap::roadmap_filter_line(filter)
}

// ---------------------------------------------------------------------------
// Overlays: the filter editor and the initiative actions (T023, T024)
// ---------------------------------------------------------------------------

/// The verb an association overlay applies.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum AssocVerb {
    /// Record the target on the selected initiative.
    Associate,
    /// Drop the target from the selected initiative.
    Dereference,
}

/// The overlay open over the Roadmap tab: the filter editor, or one initiative
/// action. All are text surfaces, so the page assigns them raw keys ahead of the
/// binding layer (`j` typed into an owner name must stay a letter).
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum RoadmapOverlay {
    /// The normalized filter editor (T023).
    Filter(FilterDraft),
    /// Create an initiative; `c`.
    Create(NameDraft),
    /// Rename the selected initiative; `e`.
    Rename(NameDraft),
    /// Associate or dereference a reference on the selected initiative; `a`/`x`.
    Associate(AssociationDraft),
}

impl RoadmapOverlay {
    /// The overlay's title.
    #[must_use]
    pub fn title(&self) -> &'static str {
        match self {
            Self::Filter(_) => "Roadmap filter",
            Self::Create(_) => "New initiative",
            Self::Rename(_) => "Rename initiative",
            Self::Associate(draft) => match draft.verb {
                AssocVerb::Associate => "Associate reference",
                AssocVerb::Dereference => "Dereference reference",
            },
        }
    }

    /// The overlay's footer hint.
    #[must_use]
    pub fn hint(&self) -> &'static str {
        match self {
            Self::Filter(_) => "type to edit · tab/↑↓ field · enter apply · esc cancel",
            Self::Create(_) => "type a name · enter create · esc cancel",
            Self::Rename(_) => "type a name · enter rename · esc cancel",
            Self::Associate(_) => "type a target · ←/→ kind · enter apply · esc cancel",
        }
    }

    /// Move the focused field by `delta`, wrapping.
    pub fn focus(&mut self, delta: isize) {
        match self {
            Self::Filter(draft) => draft.focus(delta),
            Self::Associate(draft) => draft.focus(delta),
            Self::Create(_) | Self::Rename(_) => {}
        }
    }

    /// Cycle the association **kind** by `delta` (a no-op on every other overlay).
    pub fn cycle_kind(&mut self, delta: isize) {
        if let Self::Associate(draft) = self {
            draft.cycle_kind(delta);
        }
    }

    /// Append `ch` to the focused text field.
    pub fn push(&mut self, ch: char) {
        if let Some(field) = self.field_mut() {
            field.push(ch);
        }
    }

    /// Delete the focused field's last character.
    pub fn backspace(&mut self) {
        if let Some(field) = self.field_mut() {
            field.pop();
        }
    }

    /// The focused text field, or `None` when the overlay has none.
    fn field_mut(&mut self) -> Option<&mut String> {
        match self {
            Self::Filter(draft) => Some(draft.field_mut()),
            Self::Create(draft) | Self::Rename(draft) => Some(&mut draft.value),
            Self::Associate(draft) => draft.field_mut(),
        }
    }
}

/// A single text field — the create and rename overlays.
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct NameDraft {
    /// The typed value.
    pub value: String,
}

/// The normalized filter editor: one text row per criterion, in the DTO's own
/// field order.
///
/// The DTO the draft normalizes into is [`RoadmapFilter`]; the labels are a
/// comma-separated list in **this** control only, normalized to the DTO's
/// `Vec<String>` on apply.
#[derive(Debug, Clone, Default, PartialEq, Eq)]
pub struct FilterDraft {
    /// The `period_from` row.
    pub from: String,
    /// The `period_to` row.
    pub to: String,
    /// The `owner` row.
    pub owner: String,
    /// The `status` row.
    pub status: String,
    /// The `labels` row, comma-separated.
    pub labels: String,
    /// The `query` row.
    pub query: String,
    /// The focused row.
    pub field: usize,
}

impl FilterDraft {
    /// The rows in display order; index is [`Self::field`].
    pub const ROWS: [&'static str; 6] = ["from", "to", "owner", "status", "labels", "query"];

    /// Seed the editor from an installed filter.
    #[must_use]
    pub fn from_filter(filter: &RoadmapFilter) -> Self {
        Self {
            from: filter.period_from.clone().unwrap_or_default(),
            to: filter.period_to.clone().unwrap_or_default(),
            owner: filter.owner.clone().unwrap_or_default(),
            status: filter.status.clone().unwrap_or_default(),
            labels: filter.labels.join(","),
            query: filter.query.clone().unwrap_or_default(),
            field: 0,
        }
    }

    /// Normalize the draft into **the one** filter DTO (contract §Normalized
    /// filter). A blank row is `None`/empty; `labels` splits on `,` and trims.
    #[must_use]
    pub fn to_filter(&self) -> RoadmapFilter {
        let opt = |value: &str| {
            let trimmed = value.trim();
            (!trimmed.is_empty()).then(|| trimmed.to_string())
        };
        RoadmapFilter {
            period_from: opt(&self.from),
            period_to: opt(&self.to),
            owner: opt(&self.owner),
            status: opt(&self.status),
            labels: self
                .labels
                .split(',')
                .map(str::trim)
                .filter(|label| !label.is_empty())
                .map(ToString::to_string)
                .collect(),
            query: opt(&self.query),
        }
    }

    /// The focused row's value.
    #[must_use]
    pub fn value(&self) -> &str {
        self.value_at(self.field)
    }

    /// The `index`-th row's value.
    #[must_use]
    pub fn value_at(&self, index: usize) -> &str {
        match index % Self::ROWS.len() {
            0 => &self.from,
            1 => &self.to,
            2 => &self.owner,
            3 => &self.status,
            4 => &self.labels,
            _ => &self.query,
        }
    }

    /// Move the focused row by `delta`, wrapping.
    pub fn focus(&mut self, delta: isize) {
        let len = Self::ROWS.len() as isize;
        self.field = (self.field as isize + delta).rem_euclid(len) as usize;
    }

    fn field_mut(&mut self) -> &mut String {
        match self.field % Self::ROWS.len() {
            0 => &mut self.from,
            1 => &mut self.to,
            2 => &mut self.owner,
            3 => &mut self.status,
            4 => &mut self.labels,
            _ => &mut self.query,
        }
    }
}

/// The association overlay's draft: the verb, the kind and the target.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct AssociationDraft {
    /// Whether applying the overlay associates or dereferences.
    pub verb: AssocVerb,
    /// The reference kind; cycled with `←`/`→`.
    pub kind: AssociationKind,
    /// The typed target.
    pub target: String,
    /// The focused field (`0` = kind, `1` = target).
    pub field: usize,
}

impl AssociationDraft {
    /// The kinds in cycle order.
    pub const KINDS: [AssociationKind; 3] = [
        AssociationKind::Project,
        AssociationKind::Epic,
        AssociationKind::Milestone,
    ];

    /// A fresh draft for `verb`.
    #[must_use]
    pub fn new(verb: AssocVerb) -> Self {
        Self {
            verb,
            kind: AssociationKind::Project,
            target: String::new(),
            field: 1,
        }
    }

    /// Cycle the kind by `delta`, wrapping.
    pub fn cycle_kind(&mut self, delta: isize) {
        let current = Self::KINDS
            .iter()
            .position(|kind| *kind == self.kind)
            .unwrap_or(0);
        let len = Self::KINDS.len() as isize;
        self.kind = Self::KINDS[(current as isize + delta).rem_euclid(len) as usize];
    }

    /// The kind's label in the overlay.
    #[must_use]
    pub fn kind_label(&self) -> &'static str {
        self.kind.field()
    }

    fn focus(&mut self, delta: isize) {
        let len = 2isize;
        self.field = (self.field as isize + delta).rem_euclid(len) as usize;
    }

    fn field_mut(&mut self) -> Option<&mut String> {
        (self.field % 2 == 1).then_some(&mut self.target)
    }
}

/// The initiative the create overlay builds: a name; every other field is the
/// CLI's own default and is edited later (or from `tix initiative edit`).
#[must_use]
pub fn new_initiative(draft: &NameDraft) -> NewInitiative {
    NewInitiative {
        name: draft.value.trim().to_string(),
        ..NewInitiative::default()
    }
}

/// The rename edit a [`RoadmapOverlay::Rename`] draft applies: a **label** change
/// only, so the stable id — and every association — survives (C-002).
#[must_use]
pub fn rename_edit(draft: &NameDraft) -> InitiativeEdit {
    InitiativeEdit {
        name: crate::projects::Patch::Set(draft.value.trim().to_string()),
        ..InitiativeEdit::default()
    }
}

// ---------------------------------------------------------------------------
// Rendering
// ---------------------------------------------------------------------------

/// The style of everything secondary.
fn dim() -> Style {
    Style::default().fg(Color::DarkGray)
}

/// Draw the Roadmap tab into `area`: the active criteria line, then the ordered
/// rows beside the selected row's CLI detail.
///
/// The whole tab is one function so the Portfolio page's renderer only has to
/// dispatch to it — the tab cannot drift from the page's other tabs, and the
/// page's own layout code stays untouched beyond the dispatch.
pub fn render_tab(app: &App, f: &mut Frame, area: Rect, selected: usize) {
    let split = Layout::default()
        .direction(Direction::Vertical)
        .constraints([Constraint::Length(1), Constraint::Min(1)])
        .split(area);

    let criteria = filter_context(app.roadmap_filter());
    let line = match criteria {
        Some(text) => Line::from(Span::styled(text, Style::default().fg(Color::Cyan))),
        None => Line::from(Span::styled(
            "filter: none (no criterion set) · f to edit",
            dim(),
        )),
    };
    f.render_widget(Paragraph::new(line), split[0]);

    let body = Layout::default()
        .direction(Direction::Horizontal)
        .constraints([Constraint::Percentage(55), Constraint::Min(24)])
        .split(split[1]);

    let projection = app.portfolio_roadmap();
    let rows: &[RoadmapRow] =
        projection.map_or(&[], |projection| projection.initiatives.as_slice());

    let list_title = format!("{} ({})", TAB_LABEL, rows.len());
    let list_block = Block::default().borders(Borders::ALL).title(list_title);
    if rows.is_empty() {
        // Two distinct empty states, never one blank pane: a registry with no
        // initiatives names how to fill it, a filter that selected nothing prints
        // the CLI's own sentence for that case, and a projection that could not be
        // built says so rather than panicking on a missing value.
        let text = if app.roadmap_registry_is_empty() {
            TAB_EMPTY_HINT.to_string()
        } else {
            match projection {
                Some(projection) => empty_state_lines(projection).join("\n"),
                None => "The roadmap could not be read — check the filter and the registries."
                    .to_string(),
            }
        };
        f.render_widget(
            Paragraph::new(text)
                .block(list_block)
                .wrap(Wrap { trim: true })
                .style(dim()),
            body[0],
        );
    } else {
        let lines: Vec<Line<'static>> = rows
            .iter()
            .enumerate()
            .map(|(index, row)| {
                let selected = index == selected;
                let style = if selected {
                    Style::default().add_modifier(Modifier::BOLD)
                } else {
                    Style::default()
                };
                Line::from(vec![
                    Span::raw(if selected { "> " } else { "  " }),
                    Span::styled(headline(row), style),
                ])
            })
            .collect();
        f.render_widget(Paragraph::new(lines).block(list_block), body[0]);
    }

    let detail_block = Block::default()
        .borders(Borders::ALL)
        .title(format!("{} detail", TAB_NOUN));
    match rows.get(selected) {
        Some(row) => {
            let lines: Vec<Line<'static>> = detail_lines(row)
                .into_iter()
                .map(|line| Line::from(line.replace('\t', "  ")))
                .collect();
            f.render_widget(
                Paragraph::new(lines)
                    .block(detail_block)
                    .wrap(Wrap { trim: false }),
                body[1],
            );
        }
        None => f.render_widget(
            Paragraph::new(Span::styled(
                "Nothing selected. An initiative has to exist before the page can describe it.",
                dim(),
            ))
            .block(detail_block)
            .wrap(Wrap { trim: true }),
            body[1],
        ),
    }

    render_overlay(app, f, area);
}

/// Draw the open overlay, if any, centered over `area`.
pub fn render_overlay(app: &App, f: &mut Frame, area: Rect) {
    let Some(overlay) = app.roadmap_overlay() else {
        return;
    };
    let rect = crate::ui::modal::modal_rect(area);
    f.render_widget(Clear, rect);

    let mut lines: Vec<Line<'static>> = Vec::new();
    let row = |focused: bool, key: &str, value: &str| {
        let marker = if focused { "> " } else { "  " };
        let style = if focused {
            Style::default().add_modifier(Modifier::BOLD)
        } else {
            Style::default()
        };
        Line::from(vec![
            Span::styled(format!("{marker}{key}: "), dim()),
            Span::styled(value.to_string(), style),
        ])
    };
    match overlay {
        RoadmapOverlay::Filter(draft) => {
            for (index, key) in FilterDraft::ROWS.iter().enumerate() {
                let focused = index == draft.field % FilterDraft::ROWS.len();
                let value = if focused {
                    format!("{}_", draft.value())
                } else {
                    draft.value_at(index).to_string()
                };
                lines.push(row(focused, key, &value));
            }
        }
        RoadmapOverlay::Create(draft) | RoadmapOverlay::Rename(draft) => {
            lines.push(row(true, "name", &format!("{}_", draft.value)));
        }
        RoadmapOverlay::Associate(draft) => {
            let kind = draft.kind_label().to_string();
            lines.push(row(draft.field % 2 == 0, "kind", &kind));
            let target = if draft.field % 2 == 1 {
                format!("{}_", draft.target)
            } else {
                draft.target.clone()
            };
            lines.push(row(draft.field % 2 == 1, "target", &target));
        }
    }
    lines.push(Line::from(""));
    lines.push(Line::from(Span::styled(overlay.hint(), dim())));

    f.render_widget(
        Paragraph::new(lines)
            .block(
                Block::default()
                    .borders(Borders::ALL)
                    .title(overlay.title()),
            )
            .wrap(Wrap { trim: false }),
        rect,
    );
}

#[cfg(test)]
mod tests {
    #[allow(clippy::wildcard_imports)]
    use super::*;

    #[test]
    fn the_filter_draft_normalizes_into_the_one_shared_dto() {
        let mut draft = FilterDraft::from_filter(&RoadmapFilter::default());
        assert_eq!(draft.to_filter(), RoadmapFilter::default());
        draft.from = " 2026-01-01 ".to_string();
        draft.owner = "alice".to_string();
        draft.labels = "one, two ,, three".to_string();
        draft.query = "  ".to_string();
        let filter = draft.to_filter();
        assert_eq!(filter.period_from.as_deref(), Some("2026-01-01"));
        assert_eq!(filter.owner.as_deref(), Some("alice"));
        assert_eq!(filter.labels, vec!["one", "two", "three"]);
        assert_eq!(filter.query, None, "a blank row narrows nothing");
        // The DTO's own validator owns the syntax rule.
        assert!(filter.validate().is_ok());
        let mut bad = FilterDraft::from_filter(&RoadmapFilter::default());
        bad.from = "not-a-date".to_string();
        assert!(bad.to_filter().validate().is_err());
    }

    #[test]
    fn the_filter_draft_seeds_from_an_installed_filter() {
        let filter = RoadmapFilter {
            period_to: Some("2026-12-31".to_string()),
            status: Some("active".to_string()),
            labels: vec!["a".to_string(), "b".to_string()],
            ..RoadmapFilter::default()
        };
        let draft = FilterDraft::from_filter(&filter);
        assert_eq!(draft.to, "2026-12-31");
        assert_eq!(draft.status, "active");
        assert_eq!(draft.labels, "a,b");
        assert_eq!(draft.to_filter(), filter, "a round trip through the editor");
        // The rows are the DTO's own field order.
        assert_eq!(
            FilterDraft::ROWS,
            ["from", "to", "owner", "status", "labels", "query"]
        );
    }

    #[test]
    fn focus_wraps_and_the_association_kind_cycles() {
        let mut draft = FilterDraft::from_filter(&RoadmapFilter::default());
        draft.focus(-1);
        assert_eq!(draft.field, FilterDraft::ROWS.len() - 1, "backward wraps");
        draft.focus(1);
        assert_eq!(draft.field, 0, "forward wraps");

        let mut association = AssociationDraft::new(AssocVerb::Associate);
        assert_eq!(association.kind, AssociationKind::Project);
        association.cycle_kind(1);
        assert_eq!(association.kind, AssociationKind::Epic);
        association.cycle_kind(1);
        assert_eq!(association.kind, AssociationKind::Milestone);
        association.cycle_kind(1);
        assert_eq!(association.kind, AssociationKind::Project, "forward wraps");
        association.cycle_kind(-1);
        assert_eq!(
            association.kind,
            AssociationKind::Milestone,
            "backward wraps"
        );
        // Only the target row takes text; the overlay routes characters to it.
        let mut association = AssociationDraft::new(AssocVerb::Associate);
        let mut overlay = RoadmapOverlay::Associate(association.clone());
        overlay.push('p');
        let RoadmapOverlay::Associate(focused_target) = &overlay else {
            unreachable!("the overlay is an association");
        };
        assert_eq!(focused_target.target, "p");
        overlay.backspace();
        let RoadmapOverlay::Associate(cleared) = &overlay else {
            unreachable!("the overlay is an association");
        };
        assert_eq!(cleared.target, "");
        // The kind row is not a text row: a character typed there is dropped.
        association.field = 0;
        overlay = RoadmapOverlay::Associate(association);
        overlay.push('p');
        let RoadmapOverlay::Associate(kind_row) = &overlay else {
            unreachable!("the overlay is an association");
        };
        assert!(kind_row.target.is_empty(), "the kind row takes no text");
    }

    #[test]
    fn the_action_drafts_build_the_services_own_specs() {
        let new = new_initiative(&NameDraft {
            value: "  Alpha  ".to_string(),
        });
        assert_eq!(
            new.name, "Alpha",
            "the name is trimmed, nothing else is invented"
        );
        assert!(new.outcome.is_none() && new.projects.is_empty());

        let edit = rename_edit(&NameDraft {
            value: "Renamed".to_string(),
        });
        assert_eq!(
            edit,
            InitiativeEdit {
                name: crate::projects::Patch::Set("Renamed".to_string()),
                ..InitiativeEdit::default()
            },
            "a rename touches the label only, never the stable id (C-002)"
        );
    }

    #[test]
    fn the_tab_registration_names_how_to_fill_an_empty_registry() {
        assert_eq!(TAB_LABEL, "Roadmap");
        assert_eq!(TAB_SECTION, "initiatives");
        assert_eq!(TAB_NOUN, "initiative");
        assert!(TAB_EMPTY_HINT.contains("tix initiative create"));
        for key in [
            "c create",
            "e rename",
            "a associate",
            "x dereference",
            "f filter",
        ] {
            assert!(TAB_HINT.contains(key), "the hint advertises `{key}`");
        }
    }

    #[test]
    fn the_overlay_titles_and_hints_are_stable() {
        assert_eq!(
            RoadmapOverlay::Create(NameDraft::default()).title(),
            "New initiative"
        );
        assert_eq!(
            RoadmapOverlay::Associate(AssociationDraft::new(AssocVerb::Dereference)).title(),
            "Dereference reference"
        );
        assert_eq!(
            RoadmapOverlay::Filter(FilterDraft::default()).hint(),
            "type to edit · tab/↑↓ field · enter apply · esc cancel"
        );
    }
}