#!/bin/rc

rfork en
# splits a window into an h by v grid of windows, with that window
# resized into the top-left of the grid

vars=(wsplitifs flags flagh flagv flagw flagi cmd window wcf reldim x0 xn y0 yn)
vars=($vars xd yd xd__ yd__ x y x_ y_ x__ y__ flagfmt args vars)

wsplitifs=' 		
'

flagfmt='h cols,v rows,s,w labelre,i winid'
args='[cmd args...]'
if(! ifs=() eval `$wsplitifs{aux/getflags $*} || {! ~ $#flagi 0 && ! ~ $#flagw 0 }) {
	aux/usage
	echo >[1=2] '-h: number of columns to create'
	echo >[1=2] '-v: number of rows to create'
	echo >[1=2] '-s: set scroll flag in all windows'
	echo >[1=2] '-i: id of window to split (default this window)'
	echo >[1=2] '-w: regex of window label to split (default this window)'
	echo >[1=2] 'it should be obvious that -i and -w are mutually exclusive'
}

if (~ $#* 0)
	cmd=rc
if not
	cmd=($*)

if (! ~ $#flagi 0 && ! ~ $#flagw 0) {
	echo >[1=2] 'can''t specify both -i and -w'
	exit 'bad combination of flags'
}

if (! ~ $#flagv 0 && ! test $flagv -ge 1) {
	echo >[1=2] 'bogus -v value'
	exit 'bad v splitnum'
}
if (! ~ $#flagh 0 && ! test $flagh -ge 1) {
	echo >[1=2] 'bogus -h value'
	exit 'bad h splitnum'
}

if (! ~ $#flagw 0) {
	window=`'\12'{grep -l -- $"flagw /mnt/wsys/wsys/*/label}
	if (! test $#window -eq 1) {
		echo >[1=2] $0: -w regex matched $#window windows
		exit 'bad window count'
	}
	if not
		wcf=`$wsplitifs{echo $"window | sed 's:/label$:/wctl:'}
}
if not # default to current window
	wcf=/mnt/wsys/wctl

if (! ~ $#flagi 0)
	wcf=/mnt/wsys/wsys/$flagi/wctl

if (~ $#flagh 0)
	flagh=1
if (~ $#flagv 0)
	flagv=1

# create a window using absolute coordinates
# only sane way to do this (at least without C) is to use the old-style
# attach specifier syntax:
#   Npid,minx,miny,maxx,maxy
# where pid must match the process in the new window if you want del to
# work.
fn win__ {
	@{ rfork ns
	{ # & block and unmount allow the calling window to die before children
		{unmount /mnt/acme /dev; unmount $wsys /dev} >[2]/dev/null
		if(mount $wsys /mnt/wsys N`{cat /dev/ppid}^,$1,$2,$3,$4) {
			bind -b /mnt/wsys /dev
			echo -n `{basename $"cmd} > /dev/label >[2] /dev/null
			if(! ~ $#flags 0)
				echo scroll > /dev/wctl
			rm -f /env/^$vars
			# exec to avoid changing pid again
			exec $cmd < /dev/cons > /dev/cons >[2] /dev/cons
		}
	} &
	}
}

fn floorall {
	for (i in $*)
		hoc -e 'int('^$i^')'
}

reldim=`$wsplitifs{dd -count 1 < $wcf >[2]/dev/null}

x0=$reldim(1)
y0=$reldim(2)
xn=$reldim(3)
yn=$reldim(4)
xd=`$wsplitifs{hoc -e '('^$xn^-^$x0^')/'^$flagh}
yd=`$wsplitifs{hoc -e '('^$yn^-^$y0^')/'^$flagv}
xd__=`{hoc -e 'int('^$xd^')'}
yd__=`{hoc -e 'int('^$yd^')'}

currentid=`$wsplitifs{cat /mnt/wsys/winid}

y=$y0
# do calculations with x_ and y_ (keep decimal points) and window operations
# with x__ and y__ (same values floored).
for (vi in `$wsplitifs{seq 1 1 $flagv}) {
	x=$x0
	y_=`$wsplitifs{hoc -e $y^+$yd}
	for (hi in `$wsplitifs{seq 1 1 $flagh}) {
		x_=`$wsplitifs{hoc -e $x^+$xd}
		if (test $hi -eq 1 && test $vi -eq 1) {
			echo 'current' > $wcf
			if (! ~ $#flags 0)
				echo 'scroll' > $wcf
			echo resize -dx $xd__ -dy $yd__ > $"wcf
			
			if (! ~ $#flagw 0)
				echo 'current' > /mnt/wsys/wsys/$currentid/wctl
		}
		if not
			win__ `$wsplitifs{floorall $x $y $x_ $y_} $cmd
		x=$x_
	}
	y=$y_
}

# only run cmd in this window if we resized it
if (! ~ $* '' &&  ~ $#flagi 0 && ~ $#flagw 0) {
	$cmd
}