use std::sync::OnceLock;use std::time::Duration;use std::time::Instant;use ratatui::style::Color;use ratatui::style::Modifier;use ratatui::style::Style;use ratatui::text::Span;use crate::color::blend;use crate::terminal_palette::default_bg;use crate::terminal_palette::default_fg;static PROCESS_START: OnceLock<Instant> = OnceLock::new();fn elapsed_since_start() -> Duration {    let start = PROCESS_START.get_or_init(Instant::now);    start.elapsed()}pub(crate) fn shimmer_spans(text: &str) -> Vec<Span<'static>> {    let chars: Vec<char> = text.chars().collect();    if chars.is_empty() {        return Vec::new();    }    // Use time-based sweep synchronized to process start.    let padding = 10usize;    let period = chars.len() + padding * 2;    let sweep_seconds = 2.0f32;    let pos_f =        (elapsed_since_start().as_secs_f32() % sweep_seconds) / sweep_seconds * (period as f32);    let pos = pos_f as usize;    let has_true_color = supports_color::on_cached(supports_color::Stream::Stdout)        .map(|level| level.has_16m)        .unwrap_or(false);    let band_half_width = 5.0;    let mut spans: Vec<Span<'static>> = Vec::with_capacity(chars.len());    let base_color = default_fg().unwrap_or((128, 128, 128));    let highlight_color = default_bg().unwrap_or((255, 255, 255));    for (i, ch) in chars.iter().enumerate() {        let i_pos = i as isize + padding as isize;        let pos = pos as isize;        let dist = (i_pos - pos).abs() as f32;        let t = if dist <= band_half_width {            let x = std::f32::consts::PI * (dist / band_half_width);            0.5 * (1.0 + x.cos())        } else {            0.0        };        let style = if has_true_color {            let highlight = t.clamp(0.0, 1.0);            let (r, g, b) = blend(highlight_color, base_color, highlight * 0.9);            // Allow custom RGB colors, as the implementation is thoughtfully            // adjusting the level of the default foreground color.            #[allow(clippy::disallowed_methods)]            {                Style::default()                    .fg(Color::Rgb(r, g, b))                    .add_modifier(Modifier::BOLD)            }        } else {            color_for_level(t)        };        spans.push(Span::styled(ch.to_string(), style));    }    spans}fn color_for_level(intensity: f32) -> Style {    // Tune fallback styling so the shimmer band reads even without RGB support.    if intensity < 0.2 {        Style::default().add_modifier(Modifier::DIM)    } else if intensity < 0.6 {        Style::default()    } else {        Style::default().add_modifier(Modifier::BOLD)    }}