#!/bin/sh

# Requires: xdotool, xprop (xorg-xprop)

# Size and place the focused window as a percentage of the usable screen.

# xfwm4's own tile_* keys already cover halves and quarters (Shift+Super+h/l);

# this is for the geometries it has no name for -- a centered 60% window, a

# narrow reading column. The argument is WxH, optionally +X+Y, all in percent

# of the work area, with no offset meaning centered:

#   win 60x70       60% wide, 70% tall, centered

#   win 100x40+0+0  full width, top 40%

# The win-* symlinks beside it are presets, so a keybind is a bare path with

# no arguments -- the same trick vol-up/vol-down use.

set -u

win=$(xdotool getactivewindow 2>/dev/null) || exit 0

# The name it was called by (win-center -> center), or the first argument.

geom=${1:-$(printf '%s' "${0##*/}" | sed 's/^win-*//')}

case "$geom" in

    center) geom=40x60     ;;

    big)    geom=90x90     ;;

    small)  geom=40x50     ;;

    read)   geom=45x90     ;;

    full)   geom=100x100   ;;

esac

# Split WxH[+X+Y]. A missing offset stays empty and is read as "centre me".

pw=${geom%%x*}

rest=${geom#*x}

case "$rest" in

    *+*+*) ph=${rest%%+*}; off=${rest#*+}; px=${off%%+*}; py=${off#*+} ;;

    *)     ph=$rest;       px=;            py= ;;

esac

case "$pw$ph$px$py" in

    *[!0-9]*|'') echo "usage: ${0##*/} WxH[+X+Y] | center|big|small|read|full" >&2; exit 2 ;;

esac

# xfwm4 refuses to resize a maximized window, so drop those states first;

# without this the first press after a maximize silently does nothing.

xdotool windowstate --remove MAXIMIZED_VERT --remove MAXIMIZED_HORZ "$win" 2>/dev/null

# The first desktop's work area: the screen minus polybar's reserved strip, so

# a 100%-tall window stops at the bar instead of sliding under it.

set -- $(xprop -root _NET_WORKAREA | sed 's/.*= //; s/,//g')

ax=$1 ay=$2 aw=$3 ah=$4

# windowmove places the frame, but windowsize sets the *client* area, so the

# decorations have to come off the requested size or every window lands one

# title bar too tall.

set -- $(xprop -id "$win" _NET_FRAME_EXTENTS 2>/dev/null | sed 's/.*= //; s/,//g')

fl=${1:-0} fr=${2:-0} ft=${3:-0} fb=${4:-0}

w=$((aw * pw / 100))

h=$((ah * ph / 100))

# An omitted offset centres on that axis, which is what most of the presets

# want; a given one is a percentage from the work area's top-left corner.

if [ -n "$px" ]; then x=$((ax + aw * px / 100)); else x=$((ax + (aw - w) / 2)); fi

if [ -n "$py" ]; then y=$((ay + ah * py / 100)); else y=$((ay + (ah - h) / 2)); fi

xdotool windowmove "$win" "$x" "$y" \

        windowsize "$win" $((w - fl - fr)) $((h - ft - fb))