rite_runtime/
display.rs

1//! Line-oriented rendering of protocol events for live frontends.
2//!
3//! The console driver and the TUI both surface the same `StepFact` and
4//! `UiSignal` stream; this module is the single source of truth for the
5//! short one-line summary each variant produces. Frontends pick how to
6//! style and place the line (stdout vs ratatui log feed), but the icon
7//! and text are aligned.
8//!
9//! Returns `None` for variants intentionally suppressed from the live
10//! feed (currently `StepFact::PromptAnswered`, since the prompt itself
11//! was already surfaced by `AwaitPrompt` and the operator typed the
12//! answer in front of them).
13
14use rite_model::StepFact;
15
16use crate::protocol::{Icon, UiSignal};
17
18/// One-line summary of a [`StepFact`] for live-frontend display.
19///
20/// Returns `None` for facts the live UI shouldn't surface:
21/// - `PromptAnswered`: the operator just typed it.
22/// - `BackendOperation` / `AttestationRecorded`: the surrounding action
23///   handler already calls `Reporter::log` with its own narrative line.
24/// - `CeremonyCompleted`: the frontend renders a dedicated completion
25///   screen with the fingerprint.
26#[must_use]
27pub fn fact_summary(fact: &StepFact) -> Option<(Icon, String)> {
28    match fact {
29        StepFact::CeremonyStarted { name, .. } => Some((Icon::Info, format!("Ceremony: {name}"))),
30        StepFact::ActStarted { label, .. } => Some((Icon::Info, format!("Act: {label}"))),
31        StepFact::StepStarted {
32            id,
33            label,
34            role_name,
35            ..
36        } => Some((
37            Icon::Info,
38            format!("Step {label} ({id}), role: {role_name}"),
39        )),
40        StepFact::PromptAnswered { .. }
41        | StepFact::BackendOperation { .. }
42        | StepFact::AttestationRecorded { .. }
43        | StepFact::CeremonyCompleted { .. } => None,
44        StepFact::ArtifactWritten { path, .. } => Some((
45            Icon::Checkmark,
46            format!("Artifact written: {}", path.display()),
47        )),
48        StepFact::DeviationRecorded { text, .. } => {
49            Some((Icon::Warning, format!("Deviation: {text}")))
50        }
51        StepFact::StepCompleted { outcome, .. } => match outcome {
52            rite_model::StepOutcome::Completed { message } => {
53                Some((Icon::Checkmark, message.clone()))
54            }
55            _ => Some((Icon::Checkmark, "Step completed".to_string())),
56        },
57        StepFact::CeremonyFailed { error, .. } => {
58            Some((Icon::Cross, format!("Ceremony failed: {}", error.message)))
59        }
60        // `StepFact` is `#[non_exhaustive]`; future variants may carry
61        // payloads the live UI shouldn't blindly Debug-print. Surface a
62        // typed placeholder until each new variant is given a summary.
63        _ => Some((Icon::Info, "unknown fact variant".to_string())),
64    }
65}
66
67/// One-line summary of a [`UiSignal`] for live-frontend display.
68///
69/// Returns `None` for the structured signals that frontends handle
70/// out-of-band ([`UiSignal::CeremonyOverview`], [`UiSignal::SystemInfo`],
71/// [`UiSignal::Environment`]), which populate structured fields rather than a
72/// single narration line.
73#[must_use]
74pub fn signal_summary(signal: &UiSignal) -> Option<(Icon, String)> {
75    match signal {
76        UiSignal::LogLine { icon, text, .. } => Some((*icon, text.clone())),
77        UiSignal::Progress {
78            phase, fraction, ..
79        } => {
80            let text = match fraction {
81                Some(f) => format!("{phase}: {:>5.1}%", f * 100.0),
82                None => format!("{phase}…"),
83            };
84            Some((Icon::Spinner, text))
85        }
86        UiSignal::CeremonyOverview { .. } | UiSignal::SystemInfo(_) | UiSignal::Environment(_) => {
87            None
88        }
89    }
90}
91
92/// Truncate a string to at most `max_chars` Unicode scalar values, appending
93/// `"..."` when truncation occurs.
94///
95/// Safe on multibyte input: never slices inside a UTF-8 code point.
96#[must_use]
97pub fn truncate_for_display(s: &str, max_chars: usize) -> String {
98    match s.char_indices().nth(max_chars) {
99        Some((boundary, _)) => format!("{}...", &s[..boundary]),
100        None => s.to_string(),
101    }
102}
103
104#[cfg(test)]
105mod tests {
106    use super::truncate_for_display;
107
108    #[test]
109    fn truncate_passes_through_short_input() {
110        assert_eq!(truncate_for_display("short", 10), "short");
111    }
112
113    #[test]
114    fn truncate_adds_ellipsis_when_too_long() {
115        assert_eq!(
116            truncate_for_display("this is a long string", 10),
117            "this is a ..."
118        );
119    }
120
121    #[test]
122    fn truncate_respects_utf8_code_point_boundaries() {
123        // Each emoji is a 4-byte UTF-8 sequence; naive byte slicing panics.
124        let s = "🦀🦀🦀🦀🦀";
125        assert_eq!(truncate_for_display(s, 2), "🦀🦀...");
126        assert_eq!(truncate_for_display(s, 5), "🦀🦀🦀🦀🦀");
127    }
128}
rite_runtime/display.rs

rite_runtime/
display.rs
