workspaces: a pill top left on every monitor with its workspaces

- one window per monitor (namespace magic-workspaces, Overlay like the
  island), showing that monitor's hyprland workspaces in the island's
  look: cover gradient, pink glow
- focused workspace pink, shown-elsewhere soft pink, empty ones dim;
  hover eases in (one at a time), a click switches workspace
- special workspaces are skipped; name-only ones show their first letter
- event-driven through Workspaces: redraws only on hyprland events and
  hover

src/workspaces.rs

@@ -0,0 +1,154 @@
+use std::collections::HashMap;
+use std::time::Duration;
+
+use amane::{
+    Animation, Blend, Center, Color, Full, Horizontal, InputArea, Layer, LayerWindow, Monitor, Padding, Palette, Parent, Pointer,
+    Rectangle, Row, Service, Shadow, Start, Text, Vertical, Weight, Widget, Workspace, Workspaces, Zone,
+};
+
+use crate::island::{CHIP_HOVER, CLEAR, COMPACT_H, DIM, EDGE, HOVER_MS, INK, PINK, SHADOW, TEXT, TOP_GAP, backdrop, backdrop_colors, faded};
+
+// one round slot per workspace, inside the pill's inset; the pill sits LEFT px from the monitor's edge
+const SLOT: f32 = 28.0;
+const SLOT_GAP: f32 = 4.0;
+const INSET: f32 = 5.0;
+const LEFT: f32 = 12.0;
+
+// each hovered workspace's highlight by workspace id, fading between 0 and 1
+#[derive(Default)]
+struct Hover(HashMap<i64, Animation>);
+
+impl Service for Hover {
+    fn new() -> Self {
+        Self::default()
+    }
+
+    // changes only through input
+    fn listen() {}
+}
+
+/*
+ * a pill in the top left corner of every monitor with that monitor's hyprland workspaces,
+ * in the island's look (cover gradient, pink glow). the focused workspace is pink, the one
+ * shown on another monitor a softer pink, empty ones dim; a click switches to it.
+ * Workspaces follows hyprland's events, so nothing polls
+ */
+pub fn view(monitor: &Monitor) -> LayerWindow {
+    let workspaces = Workspaces::read();
+    let hover = Hover::read();
+    let palette = Palette::read();
+
+    // special workspaces (scratchpads) aren't places to switch to
+    let here: Vec<&Workspace> = workspaces
+        .list()
+        .iter()
+        .filter(|workspace| workspace.output() == Some(monitor.name.as_str()))
+        .filter(|workspace| !workspace.name().is_some_and(|name| name.starts_with("special")))
+        .collect();
+
+    let count = here.len() as f32;
+    let width = 2.0 * INSET + count * SLOT + (count - 1.0).max(0.0) * SLOT_GAP;
+
+    let window = LayerWindow::new()
+        .width(LEFT + width + SHADOW)
+        .height(TOP_GAP + COMPACT_H + SHADOW)
+        .anchor_vertical(Vertical::Top)
+        .anchor_horizontal(Horizontal::Left)
+        // Overlay like the island: on a desktop of fullscreen windows, Top is hidden behind every one of them
+        .layer(Layer::Overlay)
+        .space(Zone::Ignore)
+        .namespace("magic-workspaces");
+
+    if here.is_empty() {
+        return window.visible(false);
+    }
+
+    let mut slots: Vec<Box<dyn Widget>> = Vec::new();
+
+    for workspace in here {
+        let id = workspace.id();
+        let lit = hover.0.get(&id).map_or(0.0, Animation::value);
+
+        // hyprland numbers its workspaces; a name-only one shows its first letter
+        let label = match workspace.name() {
+            Some(name) if workspace.index() == 0 => name.chars().next().map_or(String::new(), |letter| letter.to_uppercase().collect()),
+            _ => workspace.index().to_string(),
+        };
+
+        let (fill, color, weight) = if workspace.focused() {
+            (PINK, INK, Weight::Bold)
+        } else if workspace.active() {
+            (faded(PINK, 70), PINK, Weight::Bold)
+        } else {
+            let resting = if workspace.windows() > 0 { TEXT } else { DIM };
+
+            (Color::blend(CLEAR, CHIP_HOVER, lit), Color::blend(resting, TEXT, lit), Weight::Regular)
+        };
+
+        slots.push(Box::new(
+            Rectangle::new()
+                .width(SLOT)
+                .height(SLOT)
+                .radius(Full)
+                .fill(fill)
+                .align_child(Center, Center)
+                .scale(1.0 + 0.08 * lit)
+                .cursor(Pointer)
+                .on_hover(move |inside| hovering(id, inside))
+                .on_click(move |_| Workspaces::focus(id))
+                .child(Text::new(label).size(12.0).weight(weight).color(color)),
+        ));
+    }
+
+    let colors = backdrop_colors(&palette);
+
+    let pill = Rectangle::new()
+        .width(width)
+        .height(COMPACT_H)
+        .radius(Full)
+        .fill(backdrop(&colors, 255))
+        .border(1.0, EDGE)
+        .shadow(Shadow::drop(PINK).opacity(0.3).blur(22.0))
+        .padding(INSET)
+        .align_child(Start, Center)
+        .child(Row::new(slots).gap(SLOT_GAP).align(Center));
+
+    // clicks next to the pill reach the windows underneath
+    let region = InputArea {
+        x: LEFT as i32,
+        y: TOP_GAP as i32,
+        width: width.ceil() as i32,
+        height: COMPACT_H as i32,
+    };
+
+    window.input_region(vec![region]).child(
+        Rectangle::new()
+            .width(Parent)
+            .height(Parent)
+            .padding(Padding { top: TOP_GAP, right: 0.0, bottom: 0.0, left: LEFT })
+            .align_child(Start, Start)
+            .child(pill),
+    )
+}
+
+/*
+ * one workspace lit at a time: amane matches hover targets by their place in the frame,
+ * so a workspace that closes under the pointer never hears it leave
+ */
+fn hovering(id: i64, inside: bool) {
+    let mut hover = Hover::write();
+
+    if inside {
+        for (other, highlight) in &mut hover.0 {
+            if *other != id {
+                highlight.to(0.0);
+            }
+        }
+    }
+
+    hover
+        .0
+        .entry(id)
+        .or_insert_with(|| Animation::new(0.0).duration(Duration::from_millis(HOVER_MS)))
+        .to(if inside { 1.0 } else { 0.0 });
+}