Show a weather condition icon in xmobar

Replace the Weather plugin with weather.sh, which picks an icon from the METAR weather/sky and uses moon icons when the sun is down.

.config/xmobar/weather.sh

@@ -0,0 +1,69 @@
+#!/bin/bash
+# Current weather for xmobar, e.g. "<icon> 7°C": NOAA's decoded METAR (the source of xmobar's Weather plugin)
+# Icon from the weather, else the sky conditions; clear/partly/mostly cloudy get moon icons when the sun is down.
+# Temperature colors match the plugin's -L 0 -H 30: low up to 0, high above 30.
+
+STATION=LZIB LAT=48.2 LON=17.2
+
+declare -A ICON=(
+    [thermometer]=$'\xef\x8b\x89' [day_sunny]=$'\xee\x8c\x8d' [night_clear]=$'\xee\x8c\xab'
+    [day_cloudy]=$'\xee\x8c\x82' [night_partly_cloudy]=$'\xee\x8d\xb9' [day_sunny_overcast]=$'\xee\x8c\x8c'
+    [night_cloudy]=$'\xee\x8d\xbe' [cloudy]=$'\xee\x8c\x92' [cloud]=$'\xee\x8c\xbd'
+    [thunderstorm]=$'\xee\x8c\x9d' [rain_mix]=$'\xee\x8c\x96' [snow]=$'\xee\x8c\x9a' [showers]=$'\xee\x8c\x99'
+    [rain]=$'\xee\x8c\x98' [sprinkle]=$'\xee\x8c\x9b' [fog]=$'\xee\x8c\x93' [smoke]=$'\xee\x8d\x9c'
+    [dust]=$'\xee\x8d\x9d'
+)
+
+report=$(curl -sf --max-time 20 https://tgftp.nws.noaa.gov/data/observations/metar/decoded/"$STATION".TXT)
+temp=$(sed -n 's/^Temperature: .*(\([-0-9.]*\) C).*/\1/p' <<< "$report")
+if [[ -z $temp ]]; then
+    echo "${ICON[thermometer]} N/A"
+    exit 0
+fi
+
+# Phenomena "in the vicinity" aren't at the station; the rest are e.g. "light drizzle; mist"
+wx=$(sed -n 's/^Weather: //p' <<< "$report" | tr ';' '\n' | grep -v vicinity | tr '\n' ' ')
+wx=${wx,,}
+sky=$(sed -n 's/^Sky conditions: //p' <<< "$report")
+sky=${sky,,}
+
+# Sun above the horizon (elevation > -0.833°, as for sunrise/sunset) right now, from the low-precision solar position
+sun_up() {
+    awk -v t="$(date +%s)" -v lat="$LAT" -v lon="$LON" 'BEGIN {
+        r = atan2(0, -1) / 180; d = t / 86400 - 10957.5
+        g = (357.529 + 0.98560028 * d) * r
+        l = (280.459 + 0.98564736 * d + 1.915 * sin(g) + 0.020 * sin(2 * g)) * r
+        e = (23.439 - 0.00000036 * d) * r
+        ra = atan2(cos(e) * sin(l), cos(l)); s = sin(e) * sin(l); dec = atan2(s, sqrt(1 - s * s))
+        h = (280.46061837 + 360.98564736629 * d + lon) * r - ra
+        exit !(sin(lat * r) * sin(dec) + cos(lat * r) * cos(dec) * cos(h) > sin(-0.833 * r))
+    }'
+}
+
+case $wx in
+    *thunder*) icon=thunderstorm ;;
+    *freezing*|*sleet*|*ice\ pellets*|*hail*) icon=rain_mix ;;
+    *snow*rain*|*rain*snow*|*snow*drizzle*|*drizzle*snow*) icon=rain_mix ;;
+    *snow*) icon=snow ;;
+    *showers*) icon=showers ;;
+    *rain*) icon=rain ;;
+    *drizzle*) icon=sprinkle ;;
+    *fog*|*mist*) icon=fog ;;
+    *haze*|*smoke*) icon=smoke ;;
+    *dust*|*sand*) icon=dust ;;
+    *)
+        case $sky in
+            clear*) if sun_up; then icon=day_sunny; else icon=night_clear; fi ;;
+            "mostly clear"*|"partly cloudy"*) if sun_up; then icon=day_cloudy; else icon=night_partly_cloudy; fi ;;
+            "mostly cloudy"*) if sun_up; then icon=day_sunny_overcast; else icon=night_cloudy; fi ;;
+            overcast*|obscured*) icon=cloudy ;;
+            *) icon=cloud ;;
+        esac
+        ;;
+esac
+
+if awk -v t="$temp" 'BEGIN { exit !(t > 30) }'; then color="#ffb86c"
+elif awk -v t="$temp" 'BEGIN { exit !(t > 0) }'; then color="#50fa7b"
+else color="#8be9fd"
+fi
+echo "${ICON[$icon]} <fc=$color>$temp</fc>°C"

.config/xmobar/xmobarrc_hdmi

@@ -8,14 +8,7 @@ Config { overrideRedirect   = True
        , borderColor        = "#24283b" 
        , allDesktops        = True
        , pickBroadest       = True
-       , commands           = [ Run Weather "LZIB"
+       , commands           = [ Run Com "/home/fuxino/.config/xmobar/weather.sh" [] "weather" 9000
-                                [ "--template", "\xf2c9 <tempC>°C"
-                                , "-L", "0"
-                                , "-H", "30"
-                                , "--low"       , "#8be9fd"
-                                , "--normal"    , "#50fa7b"
-                                , "--high"      , "#ffb86c"
-                                ] 9000
                               , Run MultiCpu
                                 [ "--template"  , "\xf4bc <total>%"
                                 , "--Low"       , "25"
@@ -55,5 +48,5 @@ Config { overrideRedirect   = True
                               ]
         , sepChar           = "%"
         , alignSep          = "}{"
-        , template          = "  | %UnsafeXMonadLog% } %multicpu% %coretemp% | %memory% | <action=`/home/fuxino/.config/xmobar/kbd_cycle.sh` button=1><action=`/home/fuxino/.config/xmobar/kbd_cycle.sh prev` button=3>  %kbd%</action></action> { <action=`/home/fuxino/.config/xmobar/calcurse.sh list` button=1><action=`xdotool key super+shift+a` button=3>%calcurse%</action></action><action=`/home/fuxino/.config/xmobar/backup.sh list`>%backup%</action><action=`/home/fuxino/.config/xmobar/updates.sh list`>%updates%</action><action=`/home/fuxino/.config/xmobar/ens_brief.sh week`>%LZIB% <fc=#565f89>·</fc> %ens_brief%</action> | %pactl_volume% | %date% "
+        , template          = "  | %UnsafeXMonadLog% } %multicpu% %coretemp% | %memory% | <action=`/home/fuxino/.config/xmobar/kbd_cycle.sh` button=1><action=`/home/fuxino/.config/xmobar/kbd_cycle.sh prev` button=3>  %kbd%</action></action> { <action=`/home/fuxino/.config/xmobar/calcurse.sh list` button=1><action=`xdotool key super+shift+a` button=3>%calcurse%</action></action><action=`/home/fuxino/.config/xmobar/backup.sh list`>%backup%</action><action=`/home/fuxino/.config/xmobar/updates.sh list`>%updates%</action><action=`/home/fuxino/.config/xmobar/ens_brief.sh week`>%weather% <fc=#565f89>·</fc> %ens_brief%</action> | %pactl_volume% | %date% "
         }

.config/xmobar/xmobarrc_laptop

@@ -8,14 +8,7 @@ Config { overrideRedirect   = True
        , borderColor        = "#24283b" 
        , allDesktops        = True
        , pickBroadest       = True
-       , commands           = [ Run Weather "LZIB"
+       , commands           = [ Run Com "/home/fuxino/.config/xmobar/weather.sh" [] "weather" 9000
-                                [ "--template", "\xf2c9 <tempC>°C"
-                                , "-L", "0"
-                                , "-H", "30"
-                                , "--low"       , "#8be9fd"
-                                , "--normal"    , "#50fa7b"
-                                , "--high"      , "#ffb86c"
-                                ] 9000
                               , Run MultiCpu
                                 [ "--template"  , "\xf4bc <total>%"
                                 , "--Low"       , "25"
@@ -56,5 +49,5 @@ Config { overrideRedirect   = True
                               ]
         , sepChar           = "%"
         , alignSep          = "}{"
-        , template          = "  | %UnsafeXMonadLog% } %multicpu% %coretemp% | %memory% | <action=`/home/fuxino/.config/xmobar/kbd_cycle.sh` button=1><action=`/home/fuxino/.config/xmobar/kbd_cycle.sh prev` button=3>  %kbd%</action></action> { <action=`/home/fuxino/.config/xmobar/calcurse.sh list` button=1><action=`xdotool key super+shift+a` button=3>%calcurse%</action></action><action=`/home/fuxino/.config/xmobar/backup.sh list`>%backup%</action><action=`/home/fuxino/.config/xmobar/updates.sh list`>%updates%</action><action=`/home/fuxino/.config/xmobar/ens_brief.sh week`>%LZIB% <fc=#565f89>·</fc> %ens_brief%</action> | %pactl_volume% | %date% %_XMONAD_TRAYPAD% "
+        , template          = "  | %UnsafeXMonadLog% } %multicpu% %coretemp% | %memory% | <action=`/home/fuxino/.config/xmobar/kbd_cycle.sh` button=1><action=`/home/fuxino/.config/xmobar/kbd_cycle.sh prev` button=3>  %kbd%</action></action> { <action=`/home/fuxino/.config/xmobar/calcurse.sh list` button=1><action=`xdotool key super+shift+a` button=3>%calcurse%</action></action><action=`/home/fuxino/.config/xmobar/backup.sh list`>%backup%</action><action=`/home/fuxino/.config/xmobar/updates.sh list`>%updates%</action><action=`/home/fuxino/.config/xmobar/ens_brief.sh week`>%weather% <fc=#565f89>·</fc> %ens_brief%</action> | %pactl_volume% | %date% %_XMONAD_TRAYPAD% "
         }