polybar: Add calendar popup on date-module click

.config/polybar/launch.sh

@@ -3,11 +3,13 @@
 XDG_CONF="${XDG_CONFIG_HOME:-$HOME/.config}"
 BASE_DIR="$XDG_CONF/polybar"
 
+calendar_exec="st -A 0.45 -t polybar-datetime-calendar \"$BASE_DIR/scripts/calendar.sh\" &"
 declare -A module_flags
 module_flags=(
 	[battery]="$BASE_DIR/scripts/battery.sh"
 	[bluetooth]="$BASE_DIR/scripts/bluetooth.sh"
 	[bluetooth_click_left]="$BASE/scripts/bluetooth.sh --toggle &"
+	[datetime]="%{A1:$calendar_exec:} %date% - %time% %{A}"
 	[media]="$BASE_DIR/scripts/media.sh"
 	[powermenu]="%{A1:$XDG_CONF/rofi/powermenu.sh &:}%{T2}...%{T-}%{A}"
 	[vpn]="$BASE_DIR/scripts/vpn.sh"