pinto-cli 0.1.1

//! CLI output formatting.

use super::dependency_display::{
    DEP_ID_LIMIT, DepSummary, DependencyIndex, dependency_legend, format_ids as format_dep_ids,
};
use chrono::Duration;
use pinto::backlog::{BacklogItem, ItemId};
use pinto::service::{Burndown, CycleTimeReport, DurationSummary, ItemDetail};
use pinto::timezone::DisplayTimezone;
use std::collections::{HashMap, HashSet};
use unicode_width::{UnicodeWidthChar, UnicodeWidthStr};

pub(super) mod board;
pub(super) mod item;
pub(super) mod report;
pub(super) mod sprint;
#[cfg(test)]
use board::format_board;
#[cfg(test)]
use pinto::i18n::current;
#[cfg(test)]
use sprint::format_sprints_with_timezone;

/// Make the PBI list human-readable formatted text (ID/Status/Title, optionally point labels).
pub(super) fn format_list(items: &[BacklogItem]) -> String {
    // Alignment is based on the number of characters (according to `{:<width$}` padding and `truncate`, and does not shift even in non-ASCII).
    let id_width = items
        .iter()
        .map(|it| it.id.to_string().chars().count())
        .max()
        .unwrap_or(0);
    let status_width = items
        .iter()
        .map(|it| it.status.as_str().chars().count())
        .max()
        .unwrap_or(0);

    let mut out = String::new();
    for it in items {
        let mut line = format!(
            "{:<id_width$}  {:<status_width$}  {}",
            it.id.to_string(),
            it.status.as_str(),
            it.title,
        );
        if let Some(points) = it.points {
            line.push_str(&format!("  ({points})"));
        }
        if !it.labels.is_empty() {
            line.push_str(&format!("  [{}]", it.labels.join(", ")));
        }
        out.push_str(line.trim_end());
        out.push('\n');
    }
    out
}

#[derive(Debug, Clone, Copy, Default)]
pub(crate) struct ListLongOptions {
    pub(crate) show_labels: bool,
    pub(crate) show_sprint: bool,
    pub(crate) timezone: DisplayTimezone,
}

impl ListLongOptions {
    pub(crate) const fn new(show_labels: bool, show_sprint: bool) -> Self {
        Self {
            show_labels,
            show_sprint,
            timezone: DisplayTimezone::Local,
        }
    }

    /// Set the timezone used by the created/updated columns.
    pub(crate) const fn with_timezone(mut self, timezone: DisplayTimezone) -> Self {
        self.timezone = timezone;
        self
    }
}

/// Format the PBI list into the detailed Scrum overview table.
///
/// The stable base order is ID, TITLE, STATUS, POINTS, ASSIGNEE, CREATED, and UPDATED.
/// LABELS and SPRINT are inserted between ASSIGNEE and CREATED only when selected.
pub(super) fn format_list_long(
    items: &[BacklogItem],
    max_width: usize,
    options: ListLongOptions,
) -> String {
    if items.is_empty() {
        return String::new();
    }

    let mut headers = vec![
        "ID".to_string(),
        "TITLE".to_string(),
        "STATUS".to_string(),
        "POINTS".to_string(),
        "ASSIGNEE".to_string(),
    ];
    let title_index = 1;
    let labels_index = options.show_labels.then(|| {
        headers.push("LABELS".to_string());
        headers.len() - 1
    });
    if options.show_sprint {
        headers.push("SPRINT".to_string());
    }
    headers.push("CREATED".to_string());
    headers.push("UPDATED".to_string());

    fn or_dash(value: Option<&str>) -> String {
        value.map(str::to_string).unwrap_or_else(|| "-".to_string())
    }

    let rows: Vec<Vec<String>> = items
        .iter()
        .map(|it| {
            let mut cells = vec![
                it.id.to_string(),
                it.title.clone(),
                it.status.as_str().to_string(),
                it.points
                    .map(|points| points.to_string())
                    .unwrap_or_else(|| "-".to_string()),
                or_dash(it.assignee.as_deref()),
            ];
            if options.show_labels {
                cells.push(if it.labels.is_empty() {
                    "-".to_string()
                } else {
                    it.labels.join(", ")
                });
            }
            if options.show_sprint {
                cells.push(or_dash(it.sprint.as_deref()));
            }
            cells.push(options.timezone.format_datetime(it.created, "%Y-%m-%d"));
            cells.push(options.timezone.format_datetime(it.updated, "%Y-%m-%d"));
            cells
        })
        .collect();

    let mut widths: Vec<usize> = headers
        .iter()
        .enumerate()
        .map(|(index, header)| {
            rows.iter()
                .map(|row| display_width(&row[index]))
                .max()
                .unwrap_or(0)
                .max(display_width(header))
        })
        .collect();
    let natural_title = widths[title_index];
    let natural_labels = labels_index.map_or(0, |index| widths[index]);
    let is_variable = |index: usize| index == title_index || labels_index == Some(index);
    const WIDE_SEP: usize = 2;
    let natural_width = widths.iter().sum::<usize>() + headers.len().saturating_sub(1) * WIDE_SEP;
    let separator_width = if max_width != usize::MAX && natural_width > max_width {
        1
    } else {
        WIDE_SEP
    };
    let fixed = widths
        .iter()
        .enumerate()
        .filter(|(index, _)| !is_variable(*index))
        .map(|(_, width)| width)
        .sum::<usize>()
        + headers.len().saturating_sub(1) * separator_width;
    let available = max_width.saturating_sub(fixed);

    if let Some(labels_index) = labels_index {
        let (title_width, labels_width) =
            if natural_title.saturating_add(natural_labels) <= available {
                (natural_title, natural_labels)
            } else {
                let labels_floor = display_width("LABELS");
                let mut labels_width = natural_labels.min((available / 3).max(labels_floor));
                let title_width =
                    natural_title.min(available.saturating_sub(labels_width).max(MIN_TITLE_WIDTH));
                let leftover = available.saturating_sub(title_width + labels_width);
                labels_width = natural_labels.min(labels_width + leftover);
                (title_width, labels_width)
            };
        widths[title_index] = title_width;
        widths[labels_index] = labels_width;
    } else {
        widths[title_index] = natural_title.min(available.max(MIN_TITLE_WIDTH));
    }

    let pad = |value: &str, width: usize| -> String {
        let value_width = display_width(value);
        if value_width >= width {
            value.to_string()
        } else {
            format!("{value}{}", " ".repeat(width - value_width))
        }
    };
    let render_line = |cells: &[String]| -> String {
        let mut line = cells
            .iter()
            .enumerate()
            .map(|(index, cell)| {
                let value = if index == title_index || labels_index == Some(index) {
                    truncate(cell, widths[index])
                } else {
                    cell.clone()
                };
                pad(&value, widths[index])
            })
            .collect::<Vec<_>>()
            .join(&" ".repeat(separator_width));
        line.truncate(line.trim_end().len());
        if max_width != usize::MAX && display_width(&line) > max_width {
            line = truncate(&line, max_width);
        }
        line
    };

    let mut out = String::new();
    out.push_str(&render_line(&headers));
    out.push('\n');
    for row in &rows {
        out.push_str(&render_line(row));
        out.push('\n');
    }
    out
}

/// Format the burndown chart into human-readable text.
///
/// Draw one line per day with a horizontal bar (`█`) for remaining work and `┆` for the ideal
/// line. If `max_width` is too narrow for the bar, fall back to a numerical table while keeping
/// the remaining and ideal values readable.
pub(super) fn format_burndown(chart: &Burndown, max_width: usize) -> String {
    /// Minimum track width required for a bar; narrower output uses the numerical table.
    const MIN_TRACK: usize = 10;
    /// Fixed width outside the bar: date, spacing, borders, and spacing around the value.
    const FIXED: usize = 10 + 1 + 1 + 1 + 1;

    // Align remaining and ideal values to the width of the total, displaying ideal as a rounded integer.
    let value_width = chart.total.to_string().chars().count().max(1);

    let mut out = String::new();
    out.push_str(&format!(
        "{} {} — burndown ({})\n",
        chart.sprint_id,
        chart.sprint_title,
        chart.metric.as_str(),
    ));
    if let (Some(first), Some(last)) = (chart.days.first(), chart.days.last()) {
        out.push_str(&format!(
            "Period {} → {} · total {}\n",
            first.date, last.date, chart.total,
        ));
    }

    // Reserve the fixed fields before deciding whether a bar fits.
    let track = max_width.saturating_sub(FIXED + value_width);
    if track < MIN_TRACK {
        // Keep the `rem` and `ideal` headings wide enough for the total value.
        let rem_w = value_width.max(3);
        let ideal_w = value_width.max(5);
        out.push_str(&format!(
            "{:<10}  {:>rem_w$}  {:>ideal_w$}\n",
            "date", "rem", "ideal",
        ));
        for d in &chart.days {
            out.push_str(&format!(
                "{}  {:>rem_w$}  {:>ideal_w$}\n",
                d.date,
                d.remaining,
                d.ideal.round() as i64,
            ));
        }
        return out;
    }

    // Legend (bar = actual remaining, marker = ideal line).
    out.push_str("█ remaining  ┆ ideal\n");
    for d in &chart.days {
        let cells = scale(d.remaining, chart.total, track);
        let ideal_idx = scale_round(d.ideal, chart.total, track).min(track.saturating_sub(1));
        let mut bar: Vec<char> = (0..track)
            .map(|i| if i < cells { '█' } else { '░' })
            .collect();
        // Draw the ideal marker over the bar so it remains visible at that position.
        bar[ideal_idx] = '┆';
        let bar: String = bar.into_iter().collect();
        out.push_str(&format!(
            "{} │{}│ {:>vw$}\n",
            d.date,
            bar,
            d.remaining,
            vw = value_width,
        ));
    }
    out
}

/// Format the Cycle/Lead Time analysis (`cycletime`) as human-readable text.
///
/// If no items are complete, return a one-line summary. Otherwise, show the count, mean, median,
/// minimum, and maximum for each metric. Durations use compact date/time units. Completed items
/// without `start_at` are listed in a warning because they are excluded from Cycle Time.
pub(super) fn format_cycletime(report: &CycleTimeReport) -> String {
    let mut out = String::new();
    out.push_str(&format!(
        "Cycle/Lead time — {} completed\n",
        report.completed
    ));
    if report.completed == 0 {
        return out;
    }
    if let Some(cycle) = &report.cycle {
        out.push_str(&format!(
            "  cycle (start → done)    {}\n",
            format_summary(cycle)
        ));
    }
    if let Some(lead) = &report.lead {
        out.push_str(&format!(
            "  lead  (created → done)  {}\n",
            format_summary(lead)
        ));
    }
    if !report.missing_start.is_empty() {
        out.push_str(&format!(
            "\n⚠ {} completed item(s) without start time (excluded from cycle time): {}\n",
            report.missing_start.len(),
            format_ids(&report.missing_start),
        ));
    }
    out
}

/// Format one line of summary statistics (`n=… mean … median … min … max …`).
fn format_summary(s: &DurationSummary) -> String {
    format!(
        "n={} mean {} median {} min {} max {}",
        s.count,
        format_duration(s.mean),
        format_duration(s.median),
        format_duration(s.min),
        format_duration(s.max),
    )
}

/// Format a [`Duration`] as a compact, readable date/time value (for example, `2d 4h`, `12h 30m`,
/// `45m`, or `30s`).
///
/// Show at most two units, using enough precision for Cycle/Lead Time analysis. Zero is `0s`, and
/// negative values (such as manually edited `done_at < start_at`) receive a `-` prefix.
fn format_duration(d: Duration) -> String {
    let secs = d.num_seconds();
    if secs == 0 {
        return "0s".to_string();
    }
    let sign = if secs < 0 { "-" } else { "" };
    let secs = secs.unsigned_abs();
    let days = secs / 86_400;
    let hours = (secs % 86_400) / 3_600;
    let mins = (secs % 3_600) / 60;
    let s = secs % 60;
    let body = if days > 0 {
        if hours > 0 {
            format!("{days}d {hours}h")
        } else {
            format!("{days}d")
        }
    } else if hours > 0 {
        if mins > 0 {
            format!("{hours}h {mins}m")
        } else {
            format!("{hours}h")
        }
    } else if mins > 0 {
        if s > 0 {
            format!("{mins}m {s}s")
        } else {
            format!("{mins}m")
        }
    } else {
        format!("{s}s")
    };
    format!("{sign}{body}")
}

/// Scale `value / total` to a number of display cells; return zero when `total == 0`.
fn scale(value: u32, total: u32, width: usize) -> usize {
    if total == 0 {
        0
    } else {
        (u64::from(value) * width as u64 / u64::from(total)) as usize
    }
}

/// Scale `value / total` to display cells and round to the nearest cell; return zero when
/// `total == 0`.
fn scale_round(value: f64, total: u32, width: usize) -> usize {
    if total == 0 {
        0
    } else {
        (value / f64::from(total) * width as f64).round() as usize
    }
}

/// Format IDs separated by `, `, or return `-` when the list is empty.
fn format_ids(ids: &[ItemId]) -> String {
    if ids.is_empty() {
        "-".to_string()
    } else {
        ids.iter()
            .map(ItemId::to_string)
            .collect::<Vec<_>>()
            .join(", ")
    }
}

/// Human-readable rank cell: sibling-local ordinal plus the internal fractional
/// index. Children name their parent (`#2 under <parent-id>`) so the number
/// is clearly the order among that parent's children, not a whole-column
/// position.
fn rank_label(detail: &ItemDetail) -> String {
    match &detail.item.parent {
        Some(parent) => format!(
            "#{} under {} ({})",
            detail.rank_ordinal, parent, detail.item.rank
        ),
        None => format!("#{} ({})", detail.rank_ordinal, detail.item.rank),
    }
}

/// Format all item fields, bidirectional links, and the body as human-readable text.
///
/// If `common_dod` is `Some`, append the common Definition of Done after the item's Acceptance
/// Criteria under a separate heading. If it is `None`, display only the item's content.
pub(super) fn format_detail(
    detail: &ItemDetail,
    common_dod: Option<&str>,
    options: DetailOptions,
) -> String {
    let item = &detail.item;

    /// Labels used in the detail view to align value columns.
    const LABELS: [&str; 15] = [
        "Status",
        "Rank",
        "Points",
        "Labels",
        "Assignee",
        "Sprint",
        "Parent",
        "Children",
        "Depends on",
        "Depended by",
        "Started",
        "Completed",
        "Commits",
        "Created",
        "Updated",
    ];

    /// Return the width needed to align values after the longest ASCII label.
    const fn detail_label_width(labels: &[&str]) -> usize {
        let mut max = 0;
        let mut i = 0;
        while i < labels.len() {
            let len = labels[i].len() + 1; // The trailing colon.
            if len > max {
                max = len;
            }
            i += 1;
        }
        max + 1 // Ensure at least 1 space before the value.
    }

    const WIDTH: usize = detail_label_width(&LABELS);

    /// Format one label/value row with values aligned to the longest label.
    fn row(label: &str, value: impl AsRef<str>) -> String {
        format!("{:<WIDTH$}{}\n", format!("{label}:"), value.as_ref())
    }

    /// Display `-` for an unset optional field.
    fn or_dash(value: Option<&str>) -> String {
        value.map(str::to_string).unwrap_or_else(|| "-".to_string())
    }

    let labels = if item.labels.is_empty() {
        "-".to_string()
    } else {
        item.labels.join(", ")
    };

    let mut out = format!("{}  {}\n\n", item.id, item.title);
    out.push_str(&row("Status", item.status.to_string()));
    // Rank is a human-readable, sibling-local ordinal (`#3`), with the internal
    // fractional index in parentheses. For a child, name the parent so it is
    // clear the number is the order among that parent's children, not the column.
    out.push_str(&row("Rank", rank_label(detail)));
    out.push_str(&row(
        "Points",
        item.points
            .map(|p| p.to_string())
            .unwrap_or_else(|| "-".to_string()),
    ));
    out.push_str(&row("Labels", labels));
    out.push_str(&row("Assignee", or_dash(item.assignee.as_deref())));
    out.push_str(&row("Sprint", or_dash(item.sprint.as_deref())));
    out.push_str(&row(
        "Parent",
        item.parent
            .as_ref()
            .map(ItemId::to_string)
            .unwrap_or_else(|| "-".to_string()),
    ));
    out.push_str(&row("Children", format_ids(&detail.children)));
    out.push_str(&row("Depends on", format_ids(&item.depends_on)));
    out.push_str(&row("Depended by", format_ids(&detail.dependents)));
    out.push_str(&row(
        "Started",
        item.start_at
            .map(|d| options.timezone.format_datetime(d, "%Y-%m-%dT%H:%M:%S%:z"))
            .unwrap_or_else(|| "-".to_string()),
    ));
    out.push_str(&row(
        "Completed",
        item.done_at
            .map(|d| options.timezone.format_datetime(d, "%Y-%m-%dT%H:%M:%S%:z"))
            .unwrap_or_else(|| "-".to_string()),
    ));
    // Show abbreviated SHAs here; `--json` exposes the complete values.
    let commits = if item.commits.is_empty() {
        "-".to_string()
    } else {
        item.commits
            .iter()
            .map(|sha| sha.chars().take(8).collect::<String>())
            .collect::<Vec<_>>()
            .join(", ")
    };
    out.push_str(&row("Commits", commits));
    out.push_str(&row(
        "Created",
        options
            .timezone
            .format_datetime(item.created, "%Y-%m-%dT%H:%M:%S%:z"),
    ));
    out.push_str(&row(
        "Updated",
        options
            .timezone
            .format_datetime(item.updated, "%Y-%m-%dT%H:%M:%S%:z"),
    ));

    // Build the content region from the item body and common DoD, then render it or append it
    // verbatim according to the selected option.
    let mut content = String::new();
    if !item.body.is_empty() {
        content.push_str(&item.body);
        content.push('\n');
    }
    if let Some(dod) = common_dod {
        content.push_str("\n## Definition of Done (common)\n\n");
        content.push_str(dod);
        content.push('\n');
    }
    if !content.is_empty() {
        out.push('\n');
        if options.markdown {
            out.push_str(&super::markdown::render_body(
                &content,
                options.width,
                options.color,
            ));
        } else {
            out.push_str(&content);
        }
    }
    out
}

/// Options controlling [`format_detail`] output.
#[derive(Debug, Clone, Copy)]
pub(crate) struct DetailOptions {
    /// Render the content region (body + common DoD) as Markdown.
    pub(crate) markdown: bool,
    /// Wrap width for Markdown rendering (terminal width for the CLI).
    pub(crate) width: usize,
    /// Emit ANSI colour for a real terminal; disable it for redirected output so pipes stay clean.
    pub(crate) color: bool,
    /// Timezone used for human-readable timestamp fields.
    pub(crate) timezone: DisplayTimezone,
}

/// Default number of terminal cells when the output width cannot be determined.
pub(super) const DEFAULT_TERM_WIDTH: usize = 80;

/// Minimum title width, preserving a readable title even on very narrow terminals.
const MIN_TITLE_WIDTH: usize = 10;

/// Format the board as human-readable text.
///
/// Preserve the column order from `config.toml`, then list each column's PBIs in ascending rank
/// order. Empty columns are shown as `(empty)`. Titles are truncated with an ellipsis to fit
/// `max_width` (or [`DEFAULT_TERM_WIDTH`] for non-TTY output), accounting for fixed borders and
/// double-width characters.
///
/// Items whose status is absent from `config.toml` appear in a `(!) undefined columns` section so
/// items are still visible after a column is removed or renamed.
///
/// Dependencies (`depends_on`) appear directly below each item as marker lines (`⊸` or `⊷`); an
/// unfinished dependency is marked `⊸!`. Parent-child links (`parent`) determine tree nesting,
/// while dependency links remain flat. If the board has no dependencies, omit the markers and
/// legend to keep the output compact.
///
/// Parent-child nesting is limited to items in the same column; a parent from another column is
/// treated as absent, so the item becomes a root. Items without an in-column parent remain flat.
/// The visited set prevents cycles or duplicate rendering, ensuring every item appears once.
fn render_column_tree(
    items: &[BacklogItem],
    id_width: usize,
    max_width: usize,
    deps: &DependencyIndex,
) -> String {
    let in_column: HashSet<&ItemId> = items.iter().map(|it| &it.id).collect();

    // Build child lists in column order and collect roots, including items whose parent is in another column.
    let mut children: HashMap<ItemId, Vec<&BacklogItem>> = HashMap::new();
    let mut roots: Vec<&BacklogItem> = Vec::new();
    for it in items {
        match tree_parent(it, &in_column) {
            Some(parent) => children.entry(parent).or_default().push(it),
            None => roots.push(it),
        }
    }

    let mut renderer = TreeRenderer {
        children,
        visited: HashSet::new(),
        id_width,
        max_width,
        deps,
        out: String::new(),
    };
    for root in &roots {
        renderer.render(root, "", true, true);
    }
    // Render any item missed by the root traversal (for example, because of a cycle) in column order.
    for it in items {
        if !renderer.visited.contains(&it.id) {
            renderer.render(it, "", true, true);
        }
    }
    renderer.out
}

/// Return `item`'s parent when that parent is in the same column.
fn tree_parent(item: &BacklogItem, in_column: &HashSet<&ItemId>) -> Option<ItemId> {
    let parent = item.parent.as_ref()?;
    in_column.contains(parent).then(|| parent.clone())
}

/// Tree drawing state. Avoid argument bloat and bundle child lists, visited sets, and output.
struct TreeRenderer<'a> {
    children: HashMap<ItemId, Vec<&'a BacklogItem>>,
    visited: HashSet<&'a ItemId>,
    id_width: usize,
    /// Terminal width (truncate each line's title to fit within this width).
    max_width: usize,
    /// Dependency index for subtracting dependent destination, dependent source, and block status.
    deps: &'a DependencyIndex,
    out: String,
}

impl<'a> TreeRenderer<'a> {
    /// Draw `node` and its descendants to `out`, adding a dependency marker immediately below when needed.
    ///
    /// `ancestor_prefix` contains the ancestor connection glyphs. `is_last` identifies the last
    /// sibling, and `is_root` identifies a column root. The visited set prevents duplicate output
    /// even when the parent graph contains a cycle.
    fn render(
        &mut self,
        node: &'a BacklogItem,
        ancestor_prefix: &str,
        is_last: bool,
        is_root: bool,
    ) {
        if !self.visited.insert(&node.id) {
            return; // Stop cycles and duplicate output.
        }
        let connector = if is_root {
            ""
        } else if is_last {
            "└─ "
        } else {
            "├─ "
        };
        let id_width = self.id_width;
        // Measure the fixed prefix before the title so continuation lines can align with it.
        let head = format!(
            "  {ancestor_prefix}{connector}{:<id_width$}  ",
            node.id.to_string()
        );
        let avail = self
            .max_width
            .saturating_sub(display_width(&head))
            .max(MIN_TITLE_WIDTH);
        self.out
            .push_str(&format!("{head}{}\n", truncate(&node.title, avail)));

        // Build the child connection prefix. There is no extra indentation below a root, and the
        // marker row uses the same prefix so it aligns with the child title.
        let child_prefix = if is_root {
            String::new()
        } else {
            format!("{ancestor_prefix}{}", if is_last { "   " } else { "│  " })
        };
        if let Some(marker) = dependency_marker_line(
            &child_prefix,
            id_width,
            self.max_width,
            &self.deps.summary(node),
        ) {
            self.out.push_str(&marker);
            self.out.push('\n');
        }

        let Some(kids) = self.children.get(&node.id) else {
            return;
        };
        // Clone the references before recursing so `self` can be mutably borrowed.
        let kids: Vec<&BacklogItem> = kids.clone();
        let last = kids.len() - 1;
        for (i, kid) in kids.into_iter().enumerate() {
            self.render(kid, &child_prefix, i == last, false);
        }
    }
}

/// Format a dependency marker line (`⊸`, `⊸!`, or `⊷`).
///
/// `prefix` contains the ancestor connection line and is empty for a root. Reserve the fixed ID
/// prefix so the marker aligns with the title. Return `None` when there are no dependencies, and
/// truncate to `max_width` unless it is `usize::MAX` (`--no-truncate`).
fn dependency_marker_line(
    prefix: &str,
    id_width: usize,
    max_width: usize,
    deps: &DepSummary,
) -> Option<String> {
    if deps.is_empty() {
        return None;
    }
    let indent = format!("  {prefix}{:id_width$}  ", "");
    let mut body = String::new();
    if !deps.depends_on.is_empty() {
        let mark = if deps.blocked { "⊸!" } else { "⊸" };
        body.push_str(&format!(
            "{mark} {}",
            format_dep_ids(&deps.depends_on, DEP_ID_LIMIT)
        ));
    }
    if !deps.dependents.is_empty() {
        if !body.is_empty() {
            body.push_str("  ");
        }
        body.push_str(&format!(
            "⊷ {}",
            format_dep_ids(&deps.dependents, DEP_ID_LIMIT)
        ));
    }
    let avail = max_width
        .saturating_sub(display_width(&indent))
        .max(MIN_TITLE_WIDTH);
    Some(format!("{indent}{}", truncate(&body, avail)))
}

/// Return the terminal display width of one character.
///
/// [`unicode_width`] uses East Asian Width properties; control and undefined characters count as
/// zero cells.
fn char_width(c: char) -> usize {
    UnicodeWidthChar::width(c).unwrap_or(0)
}

/// Return the number of terminal cells occupied by `s`.
fn display_width(s: &str) -> usize {
    UnicodeWidthStr::width(s)
}

/// Truncate `s` so its display width is at most `max` cells.
///
/// If truncation is needed, replace the final cell with an ellipsis (`…`). Full-width characters
/// count as two cells, so they cannot overflow the limit. Return an empty string when `max` is zero.
fn truncate(s: &str, max: usize) -> String {
    if display_width(s) <= max {
        return s.to_string();
    }
    if max == 0 {
        return String::new();
    }
    // Reserve one cell for the ellipsis.
    let budget = max - 1;
    let mut width = 0;
    let mut out = String::new();
    for c in s.chars() {
        let w = char_width(c);
        if width + w > budget {
            break;
        }
        width += w;
        out.push(c);
    }
    out.push('…');
    out
}

#[cfg(test)]
mod tests {
    use super::*;
    use chrono::{DateTime, Utc};
    use pinto::backlog::{ItemId, Status};
    use pinto::rank::Rank;
    use pinto::service::{Board, BoardColumn};

    #[test]
    fn output_type_modules_expose_their_formatters() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![],
            }],
            orphaned: vec![],
        };

        assert_eq!(board::format_board(&board, 80), format_board(&board, 80));
    }

    fn item(number: u32, title: &str, status: &str) -> BacklogItem {
        let now = DateTime::<Utc>::from_timestamp(0, 0).expect("valid epoch");
        BacklogItem::new(
            ItemId::try_new("T", number).expect("safe test ID"),
            title,
            Status::new(status),
            Rank::between(None, None).expect("open bounds produce a rank"),
            now,
        )
        .expect("valid item")
    }

    // --- Detailed list (`list -l`) ---

    #[test]
    fn format_list_long_shows_status_points_labels_sprint_and_timestamps() {
        let mut it = item(1, "Detailed", "todo");
        it.points = Some(5);
        it.labels = vec!["backend".to_string(), "urgent".to_string()];
        it.sprint = Some("S-1".to_string());

        let out = format_list_long(
            std::slice::from_ref(&it),
            120,
            ListLongOptions::new(true, true),
        );

        assert!(out.contains("T-1"), "shows id: {out}");
        assert!(out.contains("todo"), "shows status: {out}");
        assert!(out.contains("Detailed"), "shows title: {out}");
        assert!(out.contains('5'), "shows points: {out}");
        assert!(
            out.contains("backend") && out.contains("urgent"),
            "shows labels: {out}"
        );
        assert!(out.contains("S-1"), "shows sprint: {out}");
        // The creation/update date and time (in days/UTC) will be displayed. Test item() uses epoch (1970-01-01).
        assert!(out.contains("1970-01-01"), "shows created/updated: {out}");
    }

    #[test]
    fn format_list_long_shows_dash_for_unset_optional_fields() {
        let out = format_list_long(&[item(1, "Bare", "todo")], 120, ListLongOptions::default());
        assert!(out.contains('-'), "unset fields show dash: {out}");
    }

    #[test]
    fn format_list_long_uses_configured_timezone_for_date_columns() {
        let mut it = item(1, "Boundary", "todo");
        let instant = DateTime::<Utc>::from_timestamp(30 * 60, 0).expect("timestamp");
        it.created = instant;
        it.updated = instant;
        let timezone = "-01:00".parse::<DisplayTimezone>().expect("offset");

        let out = format_list_long(
            &[it],
            120,
            ListLongOptions::default().with_timezone(timezone),
        );

        assert_eq!(
            out.lines()
                .nth(1)
                .expect("data row")
                .matches("1969-12-31")
                .count(),
            2,
            "both dates use the configured offset: {out}"
        );
    }

    #[test]
    fn format_list_long_has_header_row() {
        let out = format_list_long(&[item(1, "Task", "todo")], 120, ListLongOptions::default());
        let first_line = out.lines().next().unwrap_or_default();
        // The header indicates the column name of meta information (ID / STATUS, etc., distinguished from other lines by uppercase letters).
        assert!(first_line.contains("ID"), "header row: {first_line}");
        assert!(first_line.contains("STATUS"), "header row: {first_line}");
        assert!(first_line.contains("TITLE"), "header row: {first_line}");
    }

    #[test]
    fn format_list_long_is_empty_for_no_items() {
        assert_eq!(format_list_long(&[], 120, ListLongOptions::default()), "");
    }

    #[test]
    fn format_list_long_respects_terminal_width() {
        let long = "x".repeat(300);
        let out = format_list_long(&[item(1, &long, "todo")], 60, ListLongOptions::default());
        for line in out.lines() {
            assert!(
                display_width(line) <= 60,
                "line exceeds width 60 ({}): {line:?}",
                display_width(line)
            );
        }
        assert!(out.contains('…'), "long title is truncated: {out}");
    }

    #[test]
    fn format_list_long_unbounded_width_never_truncates() {
        let long = "x".repeat(300);
        let out = format_list_long(
            &[item(1, &long, "todo")],
            usize::MAX,
            ListLongOptions::default(),
        );
        assert!(out.contains(&long), "shows full title: {out}");
        assert!(!out.contains('…'), "no ellipsis: {out}");
    }

    #[test]
    fn format_list_long_aligns_columns_with_fullwidth_titles() {
        // Even if full-width titles are mixed, the starting positions on the display width of subsequent columns (values such as POINTS) will be aligned.
        // With padding based on the number of characters (`{:<w$}`), there is a shift because 1 full-width character = 2 display widths.
        let mut a = item(1, "あいう", "todo");
        a.points = Some(5);
        let mut b = item(2, "short", "in-progress");
        b.points = Some(7);
        let out = format_list_long(&[a, b], 120, ListLongOptions::default());
        let lines: Vec<&str> = out.lines().collect();
        assert_eq!(lines.len(), 3, "header + 2 rows: {out}");

        // Each data row has equal display width before the POINTS value ('5' / '7', which does not appear in other column values).
        let points_col = |line: &str, needle: char| -> usize {
            let idx = line.find(needle).expect("points value present");
            display_width(&line[..idx])
        };
        let a_pos = points_col(lines[1], '5');
        let b_pos = points_col(lines[2], '7');
        assert_eq!(
            a_pos, b_pos,
            "POINTS column starts at same display column: \n{out}"
        );
    }

    #[test]
    fn format_list_long_fits_width_80_with_long_status_and_labels() {
        // Fallback width 80 for non-TTY is the main case. Long states (in-progress) and long labels
        // Even if there is, all 8 column headers and date values will fit without relying on hard truncation at the end of the line.
        let mut it = item(1, "カンバン: 選択アイテムの詳細ポップアップ", "in-progress");
        it.labels = vec![
            "feature".to_string(),
            "board".to_string(),
            "kanban".to_string(),
        ];
        let out = format_list_long(
            std::slice::from_ref(&it),
            80,
            ListLongOptions::new(true, true),
        );
        let lines: Vec<&str> = out.lines().collect();

        for line in &lines {
            assert!(
                display_width(line) <= 80,
                "line exceeds width 80 ({}): {line:?}",
                display_width(line)
            );
        }
        let header = lines[0];
        assert!(
            header.contains("UPDATED"),
            "header keeps last column intact: {header:?}"
        );
        // Dates (both creation and update) are displayed in full. item() uses epoch.
        let row = lines[1];
        assert_eq!(
            row.matches("1970-01-01").count(),
            2,
            "both dates intact: {row:?}"
        );
        assert!(row.contains("in-progress"), "status intact: {row:?}");
    }

    #[test]
    fn truncate_measures_display_width_for_fullwidth_chars() {
        // Full-width characters are converted to 2 digits. "Aiueo" has a display width of 10. If max=6, 2 characters (width 4) + … = width 5.
        let out = truncate("あいうえお", 6);
        assert_eq!(out, "あい…", "got {out:?}");
        assert_eq!(display_width(&out), 5, "fits within 6 columns");
    }

    #[test]
    fn truncate_leaves_short_strings_untouched() {
        assert_eq!(truncate("abc", 10), "abc");
        assert_eq!(truncate("あいう", 6), "あいう"); // Width 6 = max, not truncated.
    }

    #[test]
    fn display_width_counts_halfwidth_as_one_and_fullwidth_as_two() {
        assert_eq!(display_width("abc"), 3);
        assert_eq!(display_width("あ"), 2);
        assert_eq!(display_width("a１"), 3); // The full-width number '1' is 2 digits.
    }

    #[test]
    fn display_width_treats_combining_marks_as_zero() {
        // U+0301 (Combined Acute Accent) has a display width of 0. 'e' + join = 1 digit.
        assert_eq!(display_width("e\u{0301}"), 1);
    }

    #[test]
    fn display_width_treats_emoji_as_two() {
        // Emoji (U+1F600) is 2 digits equivalent to full-width characters.
        assert_eq!(display_width("😀"), 2);
    }

    fn detail(item: BacklogItem) -> ItemDetail {
        ItemDetail {
            item,
            rank_ordinal: 1,
            children: vec![],
            dependents: vec![],
        }
    }

    #[test]
    fn format_detail_appends_common_dod_section_after_body() {
        let mut it = item(1, "Task", "todo");
        it.body = "- [ ] item AC".to_string();
        let out = format_detail(
            &detail(it),
            Some("- [ ] common DoD"),
            DetailOptions {
                markdown: false,
                width: 80,
                color: false,
                timezone: DisplayTimezone::Local,
            },
        );
        assert!(out.contains("- [ ] item AC"), "keeps item body: {out}");
        assert!(
            out.contains("## Definition of Done (common)"),
            "adds heading: {out}"
        );
        assert!(out.contains("- [ ] common DoD"), "adds DoD body: {out}");
        // The common DoD follows the item's body.
        assert!(out.find("item AC").unwrap() < out.find("common DoD").unwrap());
    }

    #[test]
    fn format_detail_renders_markdown_body_when_enabled() {
        let mut it = item(1, "Task", "todo");
        it.body = "# Heading\n\n**bold** text".to_string();
        let out = format_detail(
            &detail(it),
            None,
            DetailOptions {
                markdown: true,
                width: 80,
                color: false,
                timezone: DisplayTimezone::Local,
            },
        );
        // Markdown syntax is rendered away; the text content remains.
        assert!(out.contains("Heading"), "keeps heading text: {out}");
        assert!(!out.contains("# Heading"), "strips heading syntax: {out}");
        assert!(!out.contains("**bold**"), "strips emphasis syntax: {out}");
    }

    #[test]
    fn format_detail_keeps_plain_body_when_markdown_disabled() {
        let mut it = item(1, "Task", "todo");
        it.body = "# Heading\n\n**bold** text".to_string();
        let out = format_detail(
            &detail(it),
            None,
            DetailOptions {
                markdown: false,
                width: 80,
                color: false,
                timezone: DisplayTimezone::Local,
            },
        );
        // Opt-out keeps the raw Markdown verbatim.
        assert!(out.contains("# Heading"), "keeps raw heading: {out}");
        assert!(out.contains("**bold**"), "keeps raw emphasis: {out}");
    }

    #[test]
    fn format_detail_omits_dod_section_when_none() {
        let out = format_detail(
            &detail(item(1, "Task", "todo")),
            None,
            DetailOptions {
                markdown: false,
                width: 80,
                color: false,
                timezone: DisplayTimezone::Local,
            },
        );
        assert!(
            !out.contains("Definition of Done"),
            "no DoD section when unset: {out}"
        );
    }

    #[test]
    fn format_detail_uses_configured_timezone_for_all_human_timestamps() {
        let instant = DateTime::<Utc>::from_timestamp(0, 0).expect("timestamp");
        let mut it = item(1, "Task", "todo");
        it.start_at = Some(instant);
        it.done_at = Some(instant);
        it.created = instant;
        it.updated = instant;
        let out = format_detail(
            &detail(it),
            None,
            DetailOptions {
                markdown: false,
                width: 80,
                color: false,
                timezone: "+09:00".parse().expect("offset"),
            },
        );
        assert_eq!(
            out.matches("1970-01-01T09:00:00+09:00").count(),
            4,
            "all four timestamps use the configured offset: {out}"
        );
    }

    #[test]
    pub(super) fn format_board_groups_items_under_columns_in_order() {
        let board = Board {
            columns: vec![
                BoardColumn {
                    status: Status::new("todo"),
                    items: vec![item(1, "First", "todo"), item(3, "Third", "todo")],
                },
                BoardColumn {
                    status: Status::new("in-progress"),
                    items: vec![item(2, "Second", "in-progress")],
                },
                BoardColumn {
                    status: Status::new("done"),
                    items: vec![],
                },
            ],
            orphaned: vec![],
        };

        let expected = "\
todo (2)
  T-1  First
  T-3  Third

in-progress (1)
  T-2  Second

done (0)
  (empty)
";
        assert_eq!(format_board(&board, 80), expected);
    }

    #[test]
    pub(super) fn format_board_follows_terminal_width() {
        let long = "x".repeat(200);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, &long, "todo")],
            }],
            orphaned: vec![],
        };

        // Each line does not exceed the specified width (based on display width) on both narrow and wide terminals.
        let narrow = format_board(&board, 40);
        let wide = format_board(&board, 100);
        let narrow_w = narrow.lines().map(display_width).max().unwrap();
        let wide_w = wide.lines().map(display_width).max().unwrap();
        assert!(narrow.contains('…') && wide.contains('…'), "both truncate");
        assert!(
            narrow_w <= 40,
            "narrow line too wide ({narrow_w}): {narrow}"
        );
        assert!(wide_w <= 100, "wide line too wide ({wide_w}): {wide}");
        // Follows the width of the device, showing more information the wider it is.
        assert!(
            wide_w > narrow_w,
            "wider terminal shows more (fixed width?)"
        );
    }

    #[test]
    fn format_board_with_unbounded_width_never_truncates() {
        // `--no-truncate` displays the entire text with virtually unlimited width (usize::MAX).
        let long = "x".repeat(300);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, &long, "todo")],
            }],
            orphaned: vec![],
        };
        let out = format_board(&board, usize::MAX);
        assert!(out.contains(&long), "shows full title");
        assert!(!out.contains('…'), "no ellipsis: {out}");
    }

    #[test]
    fn format_board_truncates_fullwidth_titles_by_display_width() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, &"あ".repeat(80), "todo")],
            }],
            orphaned: vec![],
        };
        let out = format_board(&board, 40);
        let widest = out.lines().map(display_width).max().unwrap();
        assert!(out.contains('…'), "fullwidth title truncated: {out}");
        assert!(widest <= 40, "fullwidth line too wide ({widest}): {out}");
    }

    #[test]
    pub(super) fn format_sprints_lists_id_state_and_name() {
        use pinto::sprint::{Sprint, SprintId};
        let now = DateTime::<Utc>::from_timestamp(0, 0).expect("valid epoch");
        let planned = Sprint::new(SprintId::new("S-1").unwrap(), "Planning", now).unwrap();
        let mut active = Sprint::new(SprintId::new("sprint-2").unwrap(), "Build", now).unwrap();
        active.goal = "Ship the sprint".to_string();
        active.start(now).unwrap();

        let out = format_sprints_with_timezone(&[planned, active], DisplayTimezone::Local);

        let expected = "\
S-1       planned  Planning
sprint-2  active   Build  goal: Ship the sprint
";
        assert_eq!(out, expected);
    }

    #[test]
    pub(super) fn format_sprints_shows_period_with_minute_precision() {
        use pinto::sprint::{Sprint, SprintId};
        let now = DateTime::<Utc>::from_timestamp(0, 0).expect("valid epoch");
        let mut s = Sprint::new(SprintId::new("S-1").unwrap(), "Checkout", now).unwrap();
        s.start = Some(
            chrono::NaiveDate::from_ymd_opt(2026, 7, 6)
                .unwrap()
                .and_hms_opt(9, 30, 0)
                .unwrap()
                .and_utc(),
        );
        s.end = Some(
            chrono::NaiveDate::from_ymd_opt(2026, 7, 17)
                .unwrap()
                .and_hms_opt(18, 15, 0)
                .unwrap()
                .and_utc(),
        );

        let out = format_sprints_with_timezone(&[s], DisplayTimezone::Utc);
        assert!(
            out.contains("(2026-07-06 09:30 → 2026-07-17 18:15)"),
            "period shows minutes: {out}"
        );
    }

    #[test]
    fn format_sprints_uses_configured_timezone_for_periods() {
        use pinto::sprint::{Sprint, SprintId};
        let now = DateTime::<Utc>::from_timestamp(0, 0).expect("valid epoch");
        let mut sprint = Sprint::new(SprintId::new("S-1").unwrap(), "Boundary", now).unwrap();
        sprint.start = Some(now);
        sprint.end = Some(now);

        let out = format_sprints_with_timezone(
            &[sprint],
            "+09:00".parse::<DisplayTimezone>().expect("offset"),
        );

        assert!(
            out.contains("(1970-01-01 09:00 → 1970-01-01 09:00)"),
            "period uses configured timezone: {out}"
        );
    }

    #[test]
    pub(super) fn format_board_lists_orphaned_items_under_undefined_columns_section() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, "Kept", "todo")],
            }],
            orphaned: vec![item(2, "Stranded", "review")],
        };

        let expected = "\
todo (1)
  T-1  Kept

(!) undefined columns (1)
  T-2  Stranded  [review]
";
        assert_eq!(format_board(&board, 80), expected);
    }

    // --- Tree display ---

    fn with_parent(mut it: BacklogItem, parent: u32) -> BacklogItem {
        it.parent = Some(ItemId::try_new("T", parent).expect("safe test ID"));
        it
    }

    fn with_deps(mut it: BacklogItem, deps: &[u32]) -> BacklogItem {
        it.depends_on = deps
            .iter()
            .map(|&n| ItemId::try_new("T", n).expect("safe test ID"))
            .collect();
        it
    }

    #[test]
    fn format_board_renders_parent_child_as_tree() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![
                    item(1, "Epic", "todo"),
                    with_parent(item(2, "Story", "todo"), 1),
                    with_parent(item(3, "Task", "todo"), 2),
                ],
            }],
            orphaned: vec![],
        };

        let expected = "\
todo (3)
  T-1  Epic
  └─ T-2  Story
     └─ T-3  Task
";
        assert_eq!(format_board(&board, 80), expected);
    }

    #[test]
    fn format_board_renders_dependencies_as_flat_markers_not_tree() {
        // T-2 and T-3 depend on T-1. Dependencies are not nested in the tree, each item remains flat.
        // Represented by a dependent marker line (⊸/⊷).
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![
                    item(1, "Base", "todo"),
                    with_deps(item(2, "Dependent A", "todo"), &[1]),
                    with_deps(item(3, "Dependent B", "todo"), &[1]),
                ],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        // Tree borders (├─/└─) are not used, and all three items are lined up flat.
        assert!(
            !out.contains('├') && !out.contains('└'),
            "no tree lines: {out}"
        );
        assert!(out.contains("  T-1  Base\n"), "base flat: {out}");
        assert!(out.contains("  T-2  Dependent A\n"), "dep A flat: {out}");
        assert!(out.contains("  T-3  Dependent B\n"), "dep B flat: {out}");
        // T-2/T-3 appears in the dependents marker of T-1.
        assert!(out.contains("⊷ T-2 T-3"), "T-1 dependents marker: {out}");
        // T-1 appears on the dependencies_on marker of T-2/T-3 (blocking because it is incomplete).
        assert_eq!(
            out.matches("⊸! T-1").count(),
            2,
            "both dependents show blocked depends-on marker: {out}"
        );
    }

    #[test]
    fn format_board_leaves_unrelated_items_flat() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, "A", "todo"), item(2, "B", "todo")],
            }],
            orphaned: vec![],
        };

        let expected = "\
todo (2)
  T-1  A
  T-2  B
";
        assert_eq!(format_board(&board, 80), expected);
    }

    #[test]
    fn format_board_ignores_cross_column_relationships() {
        // If the parent is in another column, it is not nested and is treated as the root of that column.
        let board = Board {
            columns: vec![
                BoardColumn {
                    status: Status::new("todo"),
                    items: vec![with_parent(item(2, "Child", "todo"), 1)],
                },
                BoardColumn {
                    status: Status::new("done"),
                    items: vec![item(1, "Parent", "done")],
                },
            ],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        // Child of todo column is flat (parent T-1 is not nested because it is done column).
        assert!(out.contains("todo (1)\n  T-2  Child\n"), "got:\n{out}");
    }

    #[test]
    fn format_board_handles_dependency_cycles_without_looping() {
        // Even when T-1 and T-2 depend on each other, rendering must terminate and show each once.
        // Dependencies are markers, not nested tree edges.
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![
                    with_deps(item(1, "A", "todo"), &[2]),
                    with_deps(item(2, "B", "todo"), &[1]),
                ],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        assert_eq!(out.matches("T-1  A").count(), 1, "T-1 shown once: {out}");
        assert_eq!(out.matches("T-2  B").count(), 1, "T-2 shown once: {out}");
        // Mutual dependence: Both parties can both depend on and depend on (blocking).
        assert_eq!(out.matches("⊸! T-2").count(), 1, "A depends on B: {out}");
        assert_eq!(out.matches("⊸! T-1").count(), 1, "B depends on A: {out}");
    }

    // --- Dependency marker display ---

    fn done(mut it: BacklogItem) -> BacklogItem {
        it.done_at = Some(chrono::Utc::now());
        it
    }

    #[test]
    fn format_board_shows_dependency_markers_with_legend() {
        // A dependent item points to an incomplete dependency, so markers and the legend appear.
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![
                    item(1, "Base", "todo"),
                    with_deps(item(2, "Dependent", "todo"), &[1]),
                ],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        // The legend uses the same localized wording as kanban.
        let legend = dependency_legend(current());
        assert!(
            out.starts_with(&format!("{legend}\n\n")),
            "shared legend header: {out}"
        );
        assert!(out.contains("⊷ T-2"), "T-1 dependents marker: {out}");
        assert!(
            out.contains("⊸! T-1"),
            "T-2 blocked depends-on marker: {out}"
        );
    }

    #[test]
    fn format_board_omits_legend_when_no_dependencies_exist() {
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, "A", "todo"), item(2, "B", "todo")],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        assert!(
            !out.contains('⊸') && !out.contains('⊷'),
            "no markers: {out}"
        );
        assert!(!out.contains("依存先"), "no legend: {out}");
        let expected = "\
todo (2)
  T-1  A
  T-2  B
";
        assert_eq!(out, expected, "unchanged noise-free output: {out}");
    }

    #[test]
    fn format_board_omits_legend_when_marker_chars_appear_only_in_titles() {
        // A legend will not be displayed for boards that only include `⊸` / `⊷` in the title but have no dependencies.
        // (Display of the legend is determined by data, not by string search).
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![item(1, "記号 ⊸ と ⊷ を含むが依存なし", "todo")],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        let legend = dependency_legend(current());
        assert!(
            !out.contains(&legend),
            "no legend for marker chars in titles: {out}"
        );
    }

    #[test]
    fn format_board_marks_blocked_vs_resolved_dependencies() {
        // T-2 depends on unfinished T-1 (blocked) / T-4 depends on completed T-3 (resolved).
        let board = Board {
            columns: vec![
                BoardColumn {
                    status: Status::new("todo"),
                    items: vec![
                        item(1, "Base", "todo"),
                        with_deps(item(2, "Blocked", "todo"), &[1]),
                    ],
                },
                BoardColumn {
                    status: Status::new("done"),
                    items: vec![done(item(3, "Finished base", "done"))],
                },
            ],
            orphaned: vec![with_deps(item(4, "Unblocked", "todo"), &[3])],
        };

        let out = format_board(&board, 80);
        assert!(out.contains("⊸! T-1"), "blocked marker uses '!': {out}");
        assert!(
            out.contains("⊸ T-3") && !out.contains("⊸! T-3"),
            "resolved dependency has no '!': {out}"
        );
    }

    #[test]
    fn format_board_truncates_dependency_ids_beyond_limit() {
        // The number of dependent sources is 4 (maximum 3) → the first 3 dependencies + `+1` are abbreviated.
        let mut base = item(1, "Base", "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependents: Vec<BacklogItem> = (2..=5)
            .map(|n| with_deps(item(n, &format!("Dep {n}"), "todo"), &[1]))
            .collect();
        let mut items = vec![base];
        items.extend(dependents);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items,
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        assert!(
            out.contains("⊷ T-2 T-3 T-4 +1"),
            "dependents truncated with +N: {out}"
        );
        // Omitting `+N` for the number of IDs is independent of the display width, so even `--no-truncate` (unlimited width)
        // continues to be applied (as opposed to suppressing the ellipsis `…` by width).
        let unbounded = format_board(&board, usize::MAX);
        assert!(
            unbounded.contains("⊷ T-2 T-3 T-4 +1"),
            "id count truncation still applies under --no-truncate: {unbounded}"
        );
    }

    #[test]
    fn format_board_keeps_parent_child_tree_with_dependency_markers() {
        // The parent-child tree (├─/└─) is maintained, and if there is a dependency, a marker line is added below it.
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![
                    item(1, "Base", "todo"),
                    with_deps(with_parent(item(2, "Story", "todo"), 1), &[1]),
                ],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 80);
        assert!(out.contains("  T-1  Base\n"), "root flat: {out}");
        assert!(
            out.contains("  └─ T-2  Story\n"),
            "parent-child tree kept: {out}"
        );
        // The marker line appears at a position that inherits the tree's indentation (rule width).
        assert!(
            out.contains("     ⊸! T-1\n") || out.contains("     ⊸! T-1  ⊷"),
            "marker aligned under child title: {out:?}"
        );
    }

    #[test]
    fn format_board_marks_orphaned_items_too() {
        let board = Board {
            columns: vec![],
            orphaned: vec![
                item(1, "Base", "review"),
                with_deps(item(2, "Dependent", "review"), &[1]),
            ],
        };

        let out = format_board(&board, 80);
        assert!(out.contains("⊷ T-2"), "orphaned dependents marker: {out}");
        assert!(out.contains("⊸! T-1"), "orphaned depends-on marker: {out}");
    }

    #[test]
    fn format_board_truncates_dependency_marker_line_by_width() {
        let mut base = item(1, &"x".repeat(200), "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependents: Vec<BacklogItem> = (2..=9)
            .map(|n| with_deps(item(n, "d", "todo"), &[1]))
            .collect();
        let mut items = vec![base];
        items.extend(dependents);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items,
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 40);
        let legend = dependency_legend(current());
        // Legends are not subject to width restrictions. Validate only cards and dependent marker lines.
        for line in out.lines().filter(|line| *line != legend) {
            assert!(display_width(line) <= 40, "line exceeds width 40: {line:?}");
        }
    }

    #[test]
    fn format_board_with_unbounded_width_does_not_truncate_dependency_marker_line() {
        // With `--no-truncate` (usize::MAX), dependent marker lines are also not marked with an ellipsis (...) depending on their width.
        // However, the `+N` omission of the ID count (DEP_ID_LIMIT) is a mechanism independent of the display width, so
        // If the number of dependent sources exceeds the upper limit, `+N` is added as usual (here, only one item within the upper limit).
        let mut base = item(1, "Base", "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependent = with_deps(item(2, &"y".repeat(200), "todo"), &[1]);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![base, dependent],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, usize::MAX);
        assert!(!out.contains('…'), "no ellipsis in unbounded width: {out}");
        assert!(out.contains("⊸! T-1"), "marker not truncated away: {out}");
    }

    #[test]
    fn format_board_with_zero_width_falls_back_to_min_title_width() {
        // Even if the width is extremely small (0), there will be no panic or infinite loop, and it will also go to the marker line as well as the title.
        // The lower limit of MIN_TITLE_WIDTH is effective (variable parts excluding fixed parts are drawn with the lower limit width).
        let mut base = item(1, "Base", "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependents: Vec<BacklogItem> = (2..=9)
            .map(|n| with_deps(item(n, "d", "todo"), &[1]))
            .collect();
        let mut items = vec![base];
        items.extend(dependents);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items,
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 0);
        let legend = dependency_legend(current());
        // Short markers (width ≤ MIN_TITLE_WIDTH) remain.
        assert!(out.contains("⊸! T-1"), "short marker survives: {out}");
        // Long markers (8 dependent sources) are omitted at the lower limit width. The fixed part is ` {id:3} ` (width 7).
        // The legend line at the beginning (fixed header, not subject to width restrictions) is excluded from inspection.
        let dependents_line = out
            .lines()
            .find(|l| l.contains('⊷') && *l != legend)
            .unwrap_or_else(|| panic!("dependents marker line exists: {out}"));
        assert!(
            dependents_line.contains('…'),
            "truncated: {dependents_line:?}"
        );
        assert!(
            display_width(dependents_line) <= 7 + MIN_TITLE_WIDTH,
            "marker line bounded by MIN_TITLE_WIDTH floor: {dependents_line:?}"
        );
    }

    #[test]
    fn format_board_narrower_than_fixed_prefix_keeps_min_title_width() {
        // Even if the width is narrower than the fixed part (` {id} ` = width 7), it will be drawn with the lower limit MIN_TITLE_WIDTH and will not collapse.
        let mut base = item(1, "Base", "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependents: Vec<BacklogItem> = (2..=9)
            .map(|n| with_deps(item(n, "d", "todo"), &[1]))
            .collect();
        let mut items = vec![base];
        items.extend(dependents);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items,
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 5);
        let legend = dependency_legend(current());
        assert!(out.contains("⊸! T-1"), "short marker survives: {out}");
        // The legend line at the beginning (fixed header, not subject to width restrictions) is excluded from inspection.
        for line in out
            .lines()
            .filter(|l| (l.contains('⊷') || l.contains('⊸')) && *l != legend)
        {
            assert!(
                display_width(line) <= 7 + MIN_TITLE_WIDTH,
                "marker line bounded by MIN_TITLE_WIDTH floor: {line:?}"
            );
        }
    }

    #[test]
    fn format_board_handles_fullwidth_titles_with_markers_at_small_width() {
        // Even if the title + dependent marker contains full-width characters, the width calculation will not fail and each line will fit within the width.
        let mut base = item(1, "全角の長いタイトルを持つ基盤タスク", "todo");
        base.id = ItemId::try_new("T", 1).expect("safe test ID");
        let dependent = with_deps(item(2, "依存する全角タイトルのタスク", "todo"), &[1]);
        let board = Board {
            columns: vec![BoardColumn {
                status: Status::new("todo"),
                items: vec![base, dependent],
            }],
            orphaned: vec![],
        };

        let out = format_board(&board, 20);
        let legend = dependency_legend(current());
        assert!(out.contains('…'), "fullwidth titles truncated: {out}");
        assert!(out.contains("⊸! T-1"), "marker rendered: {out}");
        assert!(out.contains("⊷ T-2"), "dependents marker rendered: {out}");
        // The legend line at the beginning (fixed header, not subject to width restrictions) is excluded from inspection.
        for line in out.lines().filter(|l| *l != legend) {
            assert!(
                display_width(line) <= 20,
                "line within width 20 despite fullwidth chars: {line:?}"
            );
        }
    }

    // --- Burndown drawing ---

    fn sample_burndown() -> Burndown {
        use pinto::service::{BurndownDay, BurndownMetric};
        use pinto::sprint::SprintId;
        let d = |m, day| chrono::NaiveDate::from_ymd_opt(2026, m, day).unwrap();
        Burndown {
            sprint_id: SprintId::new("S-1").unwrap(),
            sprint_title: "Sprint One".to_string(),
            metric: BurndownMetric::Points,
            total: 8,
            days: vec![
                BurndownDay {
                    date: d(7, 6),
                    remaining: 8,
                    ideal: 8.0,
                },
                BurndownDay {
                    date: d(7, 7),
                    remaining: 5,
                    ideal: 4.0,
                },
                BurndownDay {
                    date: d(7, 8),
                    remaining: 0,
                    ideal: 0.0,
                },
            ],
        }
    }

    #[test]
    fn format_burndown_wide_draws_bars_within_width() {
        let out = format_burndown(&sample_burndown(), 80);
        assert!(
            out.contains("S-1 Sprint One — burndown (points)"),
            "header: {out}"
        );
        assert!(
            out.contains("Period 2026-07-06 → 2026-07-08"),
            "period: {out}"
        );
        assert!(out.contains('█'), "draws bars: {out}");
        assert!(out.contains('┆'), "draws ideal marker: {out}");
        // The daily bar line fits within the width of 80 (headings such as titles are not included).
        for line in out.lines().filter(|l| l.starts_with("2026-")) {
            assert!(line.width() <= 80, "line exceeds width: {line:?}");
        }
    }

    #[test]
    fn format_burndown_narrow_falls_back_to_numeric_table() {
        let out = format_burndown(&sample_burndown(), 22);
        assert!(!out.contains('█'), "no bars in narrow mode: {out}");
        assert!(out.contains("rem"), "table header has rem: {out}");
        assert!(out.contains("ideal"), "table header has ideal: {out}");
        // The remaining amount for each date is displayed as a numerical value.
        assert!(out.contains("2026-07-06"), "lists dates: {out}");
        // Daily lines fit within width 22 (headings such as titles are not included).
        for line in out.lines().filter(|l| l.starts_with("2026-")) {
            assert!(line.width() <= 22, "line exceeds width: {line:?}");
        }
    }

    #[test]
    fn format_duration_shows_up_to_two_units() {
        assert_eq!(format_duration(Duration::zero()), "0s");
        assert_eq!(format_duration(Duration::seconds(30)), "30s");
        assert_eq!(format_duration(Duration::minutes(45)), "45m");
        assert_eq!(format_duration(Duration::seconds(90)), "1m 30s");
        assert_eq!(format_duration(Duration::hours(12)), "12h");
        assert_eq!(format_duration(Duration::minutes(150)), "2h 30m");
        assert_eq!(format_duration(Duration::days(2)), "2d");
        assert_eq!(format_duration(Duration::hours(52)), "2d 4h");
        assert_eq!(format_duration(Duration::hours(-5)), "-5h");
    }

    fn sample_summary() -> DurationSummary {
        DurationSummary {
            count: 2,
            mean: Duration::hours(36),
            median: Duration::hours(30),
            min: Duration::hours(24),
            max: Duration::hours(48),
        }
    }

    #[test]
    fn format_cycletime_lists_both_metrics_and_missing_warning() {
        let report = CycleTimeReport {
            cycle: Some(sample_summary()),
            lead: Some(sample_summary()),
            missing_start: vec![ItemId::try_new("T", 7).expect("safe test ID")],
            completed: 3,
        };
        let out = format_cycletime(&report);
        assert!(out.contains("3 completed"), "shows completed count: {out}");
        assert!(out.contains("cycle (start → done)"), "cycle line: {out}");
        assert!(out.contains("lead  (created → done)"), "lead line: {out}");
        assert!(out.contains("mean 1d 12h"), "humanizes durations: {out}");
        assert!(
            out.contains("T-7") && out.contains("without start time"),
            "warns about missing start: {out}"
        );
    }

    #[test]
    fn format_cycletime_reports_no_completed_items() {
        let report = CycleTimeReport {
            cycle: None,
            lead: None,
            missing_start: Vec::new(),
            completed: 0,
        };
        let out = format_cycletime(&report);
        assert!(out.contains("0 completed"), "states none completed: {out}");
        assert!(!out.contains("cycle ("), "no metric lines: {out}");
    }
}