Add a linux waybar battery module.

ansible/roles/sway/files/waybar_battery_freebsd

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+#
+# Read battery status in FreeBSD
+set -euo pipefail
+IFS=$'\n\t'
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+
+# TODO: Which is better, apm or reading sysctls from hw.acpi.battery ?
+
+SLEEP_INTERVAL=${SLEEP_INTERVAL:-30}
+
+while true; do
+    battery_percentage=$(apm -l)
+    battery_status=$(apm -b)
+    seconds_remaining=$(apm -t)
+
+    if [ $battery_status -eq 3 ]; then
+        if [ $battery_percentage -eq 100 ]; then
+            battery_icon=""
+        else
+            battery_icon=""
+        fi
+    elif [ $battery_percentage -le 20 ]; then
+        battery_icon=""
+    elif [ $battery_percentage -le 40 ]; then
+        battery_icon=""
+    elif [ $battery_percentage -le 60 ]; then
+        battery_icon=""
+    elif [ $battery_percentage -le 80 ]; then
+        battery_icon=""
+    elif [ $battery_percentage -lt 100 ]; then
+        battery_icon=""
+    else
+        battery_icon=""
+    fi
+    if [ $seconds_remaining -eq -1 ]; then
+        time_remaining="unknown time remaining."
+    else
+        time_remaining=$(printf '%dh:%dm:%ds\n' $((seconds_remaining/3600)) $((seconds_remaining%3600/60)) $((seconds_remaining%60)) )
+    fi
+
+    jq --unbuffered --compact-output <<EOF
+{
+"text":"${battery_percentage}% ${battery_icon}",
+"tooltip":"${time_remaining}",
+"percentage":${battery_percentage}
+}
+EOF
+    sleep $SLEEP_INTERVAL
+done