# Application attention

Lime watches ICCCM `WM_HINTS` UrgencyHint and EWMH
`_NET_WM_STATE_DEMANDS_ATTENTION`. A request adds a quiet, clickable `! N`
badge to every visible Head bar. There are no flashes, popups, timers, or
automatic Activity switches. A window requesting both hints counts once.

Click the badge or use **Super-y → w → a** for a searchable list across all
Activities. The direct command search also offers “Windows needing attention”.
Entries show the Activity and the current application title. The ordinary
hidden-window picker marks requesting windows with `!`, and Activity search
shows request counts in its details.

## Visiting a request

- A leased window is focused on the Head that already owns it. It is not
  pulled onto the Head where you opened the picker. This also works for a
  non-visible member of a monocle stack.
- A hidden window is shown in its own Activity on the selected Head. If
  necessary, Lime resumes that Activity's **draft**, not an arbitrary saved View.
- Resuming a draft with contested windows still offers explicit partial/take
  choices. Opening or cancelling that choice does not change either Head.
  The target and its lease are checked again when you select an option.
- Visiting a window behind a different fullscreen window exits that fullscreen
  state so the requested window can actually be seen. Visiting the fullscreen
  window itself preserves fullscreen.
- Revealing a hidden window edits the live draft normally; it never rewrites
  a checkpoint. Merely receiving or displaying attention changes no model state.

Lime acknowledges attention when the selected, visible input target actually
has X focus, including focus inside a child widget. Another Head's saved focus,
root/background focus, and an open command-palette grab do not count. Clients
using `WM_TAKE_FOCUS` keep their request until they actually answer by taking
focus. Closing the menu after a visit then acknowledges the chosen application.

Acknowledgement clears only the urgency flag and the demands-attention atom;
other `WM_HINTS` fields, fullscreen, and unrelated EWMH state remain intact.
Applications can cancel either source independently. Destruction and genuine
withdrawal remove the client from the list; stale picker entries cannot revive it.

## Boundaries

This is **application attention**, not a desktop notification daemon or an
unread-message counter. Applications must publish the relevant X11 hints.
A game's fullscreen Head still hides its bar; another visible Head can show
the badge, and the menu remains accessible. Disabling the badge or the entire
bar does not disable the picker.

Attention is adapter-local, never part of session snapshots. Surviving X
windows have their current hints reread when adopted after a WM restart.
Dead windows and old alerts are not resurrected from disk. Hidden
`_NET_ACTIVE_WINDOW` requests which Lime declines become attention requests;
the existing activation policy for already leased clients is otherwise unchanged.

Configuration controls the badge's color, marker, and visibility; see
[bar appearance](configuration.md#bar-appearance). No personal configuration
changes are required for the default badge/menu. This addition changes backend
structure and ASDF components: use a fresh Lime process to load it, rather than
a function-only hot reload. Your running session is not modified by installing
the code.

## Implementation and tests

`src/x11/attention.lisp` owns the live source cache and acknowledgement.
ICCCM/EWMH adoption and property/client-message handlers feed it; focus effects
and normal FocusIn events acknowledge it. Focus queries run only for pending
requests, not as an idle poll. Bar/UI code consumes cached queries; the command
layer owns visiting and the ordinary Activity/lease transitions.

The owned-Xvfb smoke test is `test/x11-attention-smoke.lisp`. It covers real
ICCCM/EWMH changes and cancellation, both message atom slots, initial hints,
NoInput and asynchronous child focus, hidden and inactive Activities, bar clicks,
which-key visits, independent Heads, fullscreen preservation, stale selections,
and withdrawal/destruction. Server-free tests also cover partial/take collisions,
stale choices, checkpoint isolation, and configurable presentation.

Protocol references: [ICCCM WM_HINTS](https://www.x.org/releases/current/doc/xorg-docs/icccm/icccm.html)
and [EWMH window state](https://specifications.freedesktop.org/wm/1.5/ar01s05.html).