screen-lock: the operator's lock screen is kept, i3lock-color with its blur, ring and clock

The first version swapped the colour build for the distribution's plain i3lock and locked to black;
adopting means keeping what the operator had. Plain i3lock remains the fallback, with a blurred
screenshot of its own.

modules/screen-lock/files/bin/screen-lock

@@ -2,9 +2,11 @@
 # screen-lock (module screen-lock, novox/hq ADR 0208): the locker. xss-lock runs it on idle, before
 # suspend and on logind's Lock, and node-lock-screen's `lock` ends in it.
 #
-# The distribution's i3lock: a black screen, failed attempts shown, an empty Enter ignored. The colour
-# build the predecessor used is not in the distribution; it can come back as a pinned archive
-# (ADR 0205), and then only these options change.
+# The operator's look, adopted from the predecessor's my-i3lock: the screen as it was, blurred, with
+# an orange ring, the time and the date. That needs i3lock-color, from the distribution's user
+# repository, kept as found until the mesh carries such software (novox/hq research 027, question 1).
+# On a machine without it the distribution's i3lock shows the same blurred screen, taken here, with
+# its own plain ring; failing that, black.
 #
 # Before a suspend, xss-lock hands this script a lock on the sleep (XSS_SLEEP_LOCK_FD) and suspends
 # once it is released. The locker must not inherit it, or the machine would wait for the unlock
@@ -12,13 +14,33 @@
 # xss-lock's own documented pattern for i3lock.
 set -u
 
-options=(--color=000000 --show-failed-attempts --ignore-empty-password)
-
 # One locker: a second press of the key, or a lock while locked, changes nothing.
 if pgrep -xu "$EUID" i3lock >/dev/null; then
 	exit 0
 fi
 
+if i3lock --version 2>&1 | grep -qi color; then
+	blank='#00000000' clear='#ffffff22' accent='#ca4a00' wrong='#880000bb' verifying='#bb00bbbb'
+	options=(
+		--insidever-color="$clear" --ringver-color="$verifying"
+		--insidewrong-color="$clear" --ringwrong-color="$wrong"
+		--inside-color="$blank" --ring-color="$accent" --line-color="$blank" --separator-color="$accent"
+		--verif-color="$accent" --wrong-color="$accent" --time-color="$accent" --date-color="$accent"
+		--layout-color="$accent" --keyhl-color="$wrong" --bshl-color="$wrong"
+		--screen 1 --blur 5 --ring-width=7.0 --clock --indicator
+		--time-str="%H:%M:%S" --date-str="%A, %Y-%m-%d"
+		--time-font=sans-serif --date-font=sans-serif --verif-font=sans-serif
+		--wrong-font=sans-serif --layout-font=sans-serif --keylayout 1
+		--show-failed-attempts --ignore-empty-password
+	)
+else
+	options=(--color=000000 --show-failed-attempts --ignore-empty-password)
+	shot="${XDG_RUNTIME_DIR:-/tmp}/screen-lock.png"
+	if command -v magick >/dev/null && magick import -window root -resize 25% -blur 0x3 -resize 400% "$shot" 2>/dev/null; then
+		options+=(--image="$shot")
+	fi
+fi
+
 if [[ -e /dev/fd/${XSS_SLEEP_LOCK_FD:--1} ]]; then
 	kill_i3lock() { pkill -xu "$EUID" "$@" i3lock; }
 	trap kill_i3lock TERM INT