polybar: Handle dynamic settings through launch.sh

Since polybar supports include files, we can generate part of the bar
config with launch.sh and store it in $HOME/.cache. Since launch.sh is
a shell script, and since bspc is an interface to bspwm, we can also
change the necessary window manager settings required for different
bars, or even configure the settings for no bar at all.

A future implementation of launch.sh may allow us to change polybar
dimensions based on current resolution and whether the screen is HiDPI
or not, although it probably won't be *too* fancy since I don't need to
support every potential DPI a user may have.

Alternatively, someone could submit a patch for polybar to make it
DPI-aware. This is the ideal solution since the bar would be scaled
naturally based on dpi, instead of having to manually halve things
ourselves.

.config/polybar/config

@@ -13,45 +13,27 @@ text                        = ${xrdb:color7}
 background-alt              = ${xrdb:color8}
 
 [bar/main]
-inherit                     = bar/secondary
-
-# Make the bar float
-# offset-x                  = offset-y = window_gap in bspwmrc
-# width                     = screen resolution - offset-x * 2
-# border-size               = border_width in bspwmrc
-# border-bottom-size        = border-size / 2
-# line-size                 = border-size / 2
-offset-x                    = 30
-offset-y                    = 30
-width                       = 3780
-border-size                 = 8
-border-bottom-size          = 4
-line-size                   = 4
-
-[bar/secondary]
 modules-left                = bspwm
 modules-center              = mpd
 modules-right               = cpu ram volume date time
 
 monitor                     = VGA-1
+wm-restack                  = bspwm
+include-file                = $HOME/.cache/polybar/config
+
 foreground                  = ${color.text}
 background                  = ${color.background}
+border-color                = ${color.text}
+
 font-0                      = "Fira Mono:style=Bold:size=19"
 font-1                      = "Noto Sans CJK JP:size=19"
 font-2                      = "Font Awesome 5 Free:style=Solid:size=19"
 font-3                      = "Font Awesome 5 Free:style=Regular:size=19"
 font-4                      = "Font Awesome 5 Brands:style=Regular:size=19"
 
-height                      = 80
 padding-left                = 2
 padding-right               = 2
 module-margin               = 1
-border-color                = ${color.background-alt}
-border-bottom-size          = 4
-# line-size                 = 4
-
-# Make fullscreen programs show above polybar
-wm-restack = bspwm
 
 [module/bspwm]
 type                        = internal/bspwm

.config/polybar/launch.sh

@@ -1,12 +1,50 @@
 #!/bin/sh
 # New Start: A modern Arch workflow built with an emphasis on functionality.
-# Copyright (C) 2017 Donovan Glover
+# Copyright (C) 2017-2018 Donovan Glover
 
 # Terminate any previous instances of polybar
 killall -q polybar
 
+bspc_config() {
+  bspc config top_padding $1 &
+  bspc config border_width $2 &
+  bspc config window_gap $3 &
+}
+
+# If no bar was specified, we're done here.
+if [ -z "$1" ]; then bspc_config 0 4 0; exit; fi
+
+# Set defaults
+POLYBAR_HEIGHT=80
+HOST_WIDTH=3840
+
+# Make the bar float
+if [ "$1" == "float" ]; then
+  POLYBAR_BORDER_SIZE=8     # Later set to bspwm's border_width
+  POLYBAR_OFFSET_XY=30      # Later set to bspwm's window_gap
+  POLYBAR_WIDTH=$(($HOST_WIDTH - $POLYBAR_OFFSET_XY * 2))
+fi
+
+# Set the bspwm variables
+BSPWM_TOP_PADDING=$(($POLYBAR_HEIGHT + ${POLYBAR_OFFSET_XY:-0} + ${POLYBAR_BORDER_SIZE:-0} * 2))
+BSPWM_BORDER_WIDTH=${POLYBAR_BORDER_SIZE:-8}
+BSPWM_WINDOW_GAP=${POLYBAR_OFFSET_XY:-20}
+
+bspc_config $BSPWM_TOP_PADDING $BSPWM_BORDER_WIDTH $BSPWM_WINDOW_GAP
+
+# Make the polybar config
+mkdir -p $HOME/.cache/polybar
+
+cat >$HOME/.cache/polybar/config <<EOL
+width                       = ${POLYBAR_WIDTH:-3840}
+height                      = $POLYBAR_HEIGHT
+offset-x                    = ${POLYBAR_OFFSET_XY:-0}
+offset-y                    = ${POLYBAR_OFFSET_XY:-0}
+border-size                 = ${POLYBAR_BORDER_SIZE:-0}
+EOL
+
 # Wait until there are no more polybar instances running
 while pgrep -u $UID -x polybar >/dev/null; do sleep 1; done
 
 # Start polybar
-launch polybar secondary
+launch polybar main