//! Theming for bos-settings.
//!
//! bos-settings deliberately owns almost no styling: it loads the ecosystem's
//! shared stylesheet (the same one breadbar/breadbox/breadpad use, generated by
//! `bread-theme` from the pywal palette) and adds only the few layout rules
//! specific to this app's sidebar + content shell. This keeps it visually
//! identical to the rest of the bread desktop and live-recolouring for free.

use gtk4::CssProvider;
use std::cell::RefCell;

// App-specific layout only — everything visual (colours, buttons, entries,
// switches, sidebar/row styling, cards, scrollbars) comes from the shared sheet.
const APP_CSS: &str = "\
.view-content { padding: 24px; }\n\
.view-content > label.title { margin-bottom: 16px; }\n\
/* Sidebar row sub-labels (the underlying binary/config name under a row's \
   human label) — smaller than the shared sheet's default dim-label size. */\n\
.caption { font-size: 11px; }\n\
/* bread-theme's shared sheet only overrides background-color on \
   suggested/destructive buttons, not background-image — so Adwaita's \
   built-in gradient (bright blue/red) paints over our flat colour \
   underneath it. Belongs upstream in bread-theme; patched locally here \
   until that's worth its own release. */\n\
button.suggested-action, button.destructive-action { background-image: none; }\n\
/* Same upstream gap for scale (Sound's volume sliders) — the shared sheet \
   has no `scale` rules at all, so they render in Adwaita's default blue. */\n\
scale trough { background-color: alpha(@on-surface, 0.15); border-radius: 999px; min-height: 6px; background-image: none; }\n\
scale highlight { background-color: @accent; background-image: none; border-radius: 999px; }\n\
scale slider { background-color: @on-surface; border-radius: 999px; }\n\
/* Destructive actions must not follow the wallpaper palette: @red is \
   pywal's color1, which can land on gold/yellow/anything depending on the \
   wallpaper (it did, this session) — making Delete/Remove look like a \
   primary action instead of a dangerous one. Fixed regardless of palette. */\n\
button.destructive-action { background-color: #c0392b; color: #ffffff; }\n\
button.destructive-action:hover { background-color: #d64535; }\n\
/* Adwaita's default switch slider (the knob) carries a box-shadow used for \
   its 3D bevel look — bread-theme's override only sets background-color, \
   so that shadow still renders as a pale ring around the knob on top of \
   our flat colour. */\n\
switch slider { box-shadow: none; outline: none; border: none; background-image: none; }\n\
switch { box-shadow: none; outline: none; border: none; background-image: none; }\n\
";

thread_local! {
    static APP_PROVIDER: RefCell<Option<CssProvider>> = const { RefCell::new(None) };
}

pub fn load(_display: &gtk4::gdk::Display) {
    // Shared ecosystem stylesheet (loads the generated file or a rendered
    // fallback, and live-reloads when the palette changes).
    bread_theme::gtk::apply_shared();

    // bos-settings layout, layered on top at APPLICATION priority.
    APP_PROVIDER.with(|cell| bread_theme::gtk::apply_css(APP_CSS, cell));
}