xmobar: show the next calcurse appointment

Time of today's next appointment, or an icon for a whole-day event today or an appointment tomorrow; click lists both days, right-click opens the calcurse scratchpad. Uptime dropped and the date shortened to make room.

.config/xmobar/calcurse.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+# Next calcurse item for xmobar: pink " 10:15 | " for an appointment later today, a cyan icon for a whole-day
+# event today, a pink icon alone when the next appointment is tomorrow; empty otherwise.
+# With "list": show today's and tomorrow's items in a notification (for a click on the bar)
+set -uo pipefail
+
+icon=$'\xf3\xb0\x83\xad'    # nf-md-calendar, as UTF-8 bytes so the locale doesn't matter
+today=$(date +%F)
+
+query() {
+    calcurse -Q --filter-type cal --days 2 --output-datefmt %F "$@"
+}
+
+if [[ ${1:-} == list ]]; then
+    tomorrow=$(date -d tomorrow +%F)
+    body=$(query --format-apt '%S–%E  %m\n' --format-recur-apt '%S–%E  %m\n' \
+        --format-event 'all day  %m\n' --format-recur-event 'all day  %m\n' |
+        sed -e 's/&/\&amp;/g; s/</\&lt;/g; s/>/\&gt;/g' -e "s/^$today:$/Today:/; s/^$tomorrow:$/Tomorrow:/")
+    notify-send -a calcurse -i x-office-calendar "Calendar" "${body:-Nothing today or tomorrow}"
+    exit
+fi
+
+now=$(date +%s)
+day="" next="" event=false
+while read -r kind start; do
+    case $kind in
+    *:) day=${kind%:} ;;
+    A) [[ -z $next ]] && ((start > now)) && next=$start ;;
+    E) [[ $day == "$today" ]] && event=true ;;
+    esac
+done < <(query --format-apt 'A %s\n' --format-recur-apt 'A %s\n' --format-event 'E\n' --format-recur-event 'E\n')
+
+if [[ -n $next && $(date -d "@$next" +%F) == "$today" ]]; then
+    text="<fc=#ff79c6>$icon $(date -d "@$next" +%H:%M)</fc>"
+elif $event; then
+    text="<fc=#8be9fd>$icon</fc>"
+elif [[ -n $next ]]; then
+    text="<fc=#ff79c6>$icon</fc>"
+else
+    exit 0
+fi
+echo "$text | "