//! The one-row footer: key hints along the bottom.
//!
//! Was `alloy_tui::AlloyStatusBar`. It moved here when `got` stopped depending
//! on Alloy's design system: the colour mapping it needs is family-level and
//! now lives in `makeover-tui`, but a footer's layout is this app's opinion
//! about its own chrome, not something two unrelated programs should share.
//!
//! Only the hint half came across. The original also carried a right-aligned
//! transient status slot; `got` never set one, and an unused builder method is
//! a worse thing to keep than fifteen lines are to rewrite if it is ever
//! wanted.

use makeover_tui::Theme;
use ratatui::buffer::Buffer;
use ratatui::layout::Rect;
use ratatui::style::Style;
use ratatui::text::{Line, Span};
use ratatui::widgets::{Paragraph, Widget};

/// A footer key hint: the key, and what it does.
pub(crate) struct Hint {
    pub(crate) key: &'static str,
    pub(crate) label: &'static str,
}

/// Terse constructor, so hint lists read as data at the call site:
/// `[hint("Tab", "group"), hint("q", "quit")]`.
pub(crate) const fn hint(key: &'static str, label: &'static str) -> Hint {
    Hint { key, label }
}

pub(crate) struct StatusBar<'a> {
    theme: &'a Theme,
    hints: Vec<Hint>,
}

impl<'a> StatusBar<'a> {
    pub(crate) fn new(theme: &'a Theme, hints: impl IntoIterator<Item = Hint>) -> Self {
        Self {
            theme,
            hints: hints.into_iter().collect(),
        }
    }
}

impl Widget for StatusBar<'_> {
    fn render(self, area: Rect, buf: &mut Buffer) {
        // The bar reads as its own band, so the whole row takes the sunken
        // surface first and every span below is drawn onto it.
        let base = Style::default().bg(self.theme.surface_sunken);
        Paragraph::new("").style(base).render(area, buf);

        let mut spans: Vec<Span> = Vec::with_capacity(self.hints.len() * 3);
        for (i, h) in self.hints.iter().enumerate() {
            if i > 0 {
                spans.push(Span::raw("   "));
            }
            // The key takes the action colour and the label is muted: a key
            // hint IS the actionable element, which is the one place accent on
            // text is not decoration.
            spans.push(Span::styled(
                h.key,
                Style::default().fg(self.theme.action_primary),
            ));
            spans.push(Span::raw(" "));
            spans.push(Span::styled(
                h.label,
                Style::default().fg(self.theme.content_muted),
            ));
        }
        Paragraph::new(Line::from(spans))
            .style(base)
            .render(area, buf);
    }
}