#! /bin/sh
# $Header: /home/jerry/.bin/RCS/showmult,v 1.3 92/08/10 11:39:56 jerry mh_contrib $
###	showmult - show multiple MH messages; pass as separate files to pager
###	Usage (in MH profile):   mhl: -moreproc showmult
##
##	showmult FIXES AN IRRITATING MH show PROBLEM: BY DEFAULT, MH WITH mhl
##	READS ALL THE MESSAGE FILES YOU WANT TO SEE AT ONCE AND PIPES THEM ALL
##	TO YOUR PAGER (LIKE more).  SO, YOU CAN'T ASK THE PAGER TO JUMP BACK
##	AND FORTH WITHIN OR BETWEEN THE MESSAGES.
##
##	showmult WORKS AROUND THIS BY FEEDING THE INDIVIDUAL FILES FROM THE
##	mhl OUTPUT TO csplit -- SPLITTING THEM INTO SEPARATE FILES, THEN GIVING
##	THE INDIVIDUAL FILES TO THE PAGER.
##
#	ASSUMES THAT YOU'RE USING AN mhl FORMAT FILE THAT PUTS
#		>>> foldername:msgnum
#	AT THE START OF EVERY MESSAGE.
#
#	NOTE TO HACKERS: TABSTOPS SET AT 4 IN THIS CODE
#
#	USE AT YOUR OWN RISK.  SEEMS TO WORK, BUT IT'S YOUR RESPONSIBILITY!
#	PLEASE TELL ME ABOUT BUGS AND FIXES: Jerry Peek, jerry@ora.com

pager=${PAGER-less}	# PROGRAM FOR PAGING THRU MESSAGES (DEFAULT IS "less")
# START SEPARATOR LINE LIKE THE ONE mhl SHOULD OUTPUT ($mhfolder IS FOLDER NAME)
sep=">>> ${mhfolder?}:"
# SET PREFIX (LIKE msg12345-01, msg12345-02) FOR FILES csplit MAKES IN /tmp:
msgs=msg$$-
temp=/tmp/SHOWMULT$$
umask 077	# MAKE ALL TEMP FILES PRIVATE
trap 'rm -f $temp ${msgs}*; exit' 0 1 2 15

cat > $temp		# READ TEXT FROM mhl ON OUR STANDARD INPUT

# NUMBER OF SEPARATORS IN THE FILE = NUMBER OF MESSAGES.
numseps="`egrep -c \"^$sep\" $temp`"
case $? in
2)	echo "`basename $0` quitting: egrep bombed." 1>&2
	exit
	;;
esac

case "$numseps" in
0)	$pager $temp ;;	# NO SEPARATOR IF LESS THAN 2 MESSAGES
1)	# ONE SEPARATOR???  SHOW MESSAGE(S), THEN COMPLAIN:
	$pager $temp
	echo "`basename $0`: warning: wild message separator?  Couldn't split that." 1>&2
	;;
[2-9]|[1-9][0-9])
	# BETWEEN 2 AND 99 MESSAGES.  SHOW THEM.
	# FIRST, GET REPETITION NUMBER FOR csplit:
	repeats="`expr $numseps - 1`"
	cd /tmp
	# IF $sep HAS A "/" IN IT, ADD BACKSLASH(ES) TO KEEP csplit FROM PUKING:
	case "$sep" in
	*/*) sep="`echo \"$sep\" | sed 's@/@\\\\/@g'`" ;;
	esac
	if csplit -s -f $msgs $temp "/^$sep/" "{$repeats}"
	then
		rm -f ${msgs}00		# FIRST FILE IS ALWAYS EMPTY, SIGH
		$pager ${msgs}*
	else
		echo "`basename $0`: quitting: problem with 'csplit'?" 1>&2
	fi
	;;
[1-9]*)
	# csplit CAN'T HANDLE MORE THAN 100 MESSAGES AND WE CAN'T DO MORE THAN 99:
	echo "`basename $0`: sorry, can't handle more than 99 messages." 1>&2
	;;
*)	echo 1>&2 "`basename $0`: quitting: wild 'egrep -c' output?:
	$numseps"
	;;
esac

exit	# SHOULD REALLY SET A STATUS, I GUESS