#! /bin/sh
# Prepare up to $3 batches of nominal size $1, max size $2, bytes in files
#   named togo.[0-9] .
# Exit status:  0 some have been prepared, 1 none can be.
# This is now just central administration, with batchsplitter doing the work.

# =()<. ${NEWSCONFIG-@<NEWSCONFIG>@}>()=
. ${NEWSCONFIG-/usr/local/libexec/cnews/config}

PATH=$NEWSCTL/bin:$NEWSBIN/batch:$NEWSBIN:$NEWSPATH ; export PATH
umask $NEWSUMASK

regress=n
case "$1" in
'')	echo "Usage: $0 size max [nwanted]" >&2
	exit 2
	;;
-X)	regress=y
	shift
	;;
esac

nominal=$1
max=$2

# Limit $3 to 7, to stay within awk's limits on file descriptors.
case "$3" in
[1-7])	nwanted="$3"	;;
*)	nwanted=7	;;
esac

# We ultimately work from togo, but if it's all we've got, we immediately
# rename it togo.more so that we can unlock the news system.  If there
# is more than will fit in the numbered batches, we put the next few
# lots in togo.next, and use that thereafter until it's empty.  This
# avoids the need to paw through a long togo.more every time when there's
# a large backlog.
if test -s togo.next
then
	input=togo.next
elif test -s togo.more
then
	input=togo.more
else
	sigs='1 2 15'
	lock LOCKexplode $$ || exit 1
	trap "unlock LOCKexplode ; exit 1" $sigs
	rm -f togo.more
	mv togo togo.more
	>togo
	input=togo.more
	trap $sigs
	unlock LOCKexplode
fi

# A little precaution... do there seem to be a lot of nonexistent files?
# Check first three as quick screening, check next fifty to decide whether
# a relatively-costly existence filtering is in order.
nextonly=0
lotsmissing=25
if test " $regress" = " y"
then
	lotsmissing=0
fi
if test " `sed 3q $input | batchcheck -v | wc -l`" -gt 0 && \
	test " `sed 50q $input | batchcheck -v | wc -l`" -gt $lotsmissing
then
	# We filter only togo.next, because filtering a big togo.more is
	# a tedious job and best done a bit at a time.
	while test -s $input
	do
		if test " $input" != " togo.next"
		then
			batchsplitter $input $nominal $max 0
			input=togo.next
		fi
		batchcheck <togo.next >togo.tmp
		mv togo.tmp togo.next
		test -s togo.next && break	# if have articles, BREAK OUT
		input=togo.more			# no luck -- try again
	done
fi

if test -s $input
then
	batchsplitter $input $nominal $max $nwanted
	exit 0
else
	exit 1
fi