mb

#!/bin/sh

# mb [-nq1] [folder [command...]] - thin REPL for mblaze(7)

# If invoked with -n, we display only new mail in whatever folder
# we're examining, which by default is your inbox as configured in
# ~/.mblaze/profile or in the envar INBOX.  See the README.md file for
# more on configuration.  If invoked with -q, we skip listing the
# folder and printing a usage summary at start (quiet start).  Any
# additional arguments beyond the folder are interpreted as a command
# and executed immediately upon startup.  If the -1 option is given,
# then we do not drop into the main loop and instead only execute
# whatever command was given as arguments and exit.

# Switch between new/cur sides of a Maildir w/the new/cur commands.

# The help system is based on hash-plus comments in this script, c.f
# the give_help function, below.

# type "brief" at the prompt for a brief usage summary
# type "help" for one-line summaries on each command
# type "help <cmd>" for more detailed help on <cmd>
# hit ^\ for a brief status report on the current folder
# use ^C to interrupt something, you land back in the loop

# This script comes with a small Perl program, rl, which uses GNU
# ReadLine and handles history.  For it to work you have to have the
# Term::ReadLine::Gnu Perl module installed on your system (pkg_add
# p5-Term-ReadLine-Gnu on OpenBSD).

alias my=typeset
# pirate version:
# alias me=typeset

SCRIPT=$0
OUR_CMDS=$(grep '#\+' $SCRIPT | \
		   sed -e 's/^.*#\+ //' | \
		   awk '{ print $1 }' | sort -u)
OUR_CMDLIST=$(echo ${OUR_CMDS} | sed -e 's/ /,/g')

# query config in ~/.mblaze/profile
MBLAZE=${MBLAZE-$HOME/.mblaze}
profile="$MBLAZE/profile"
basedir=$(mhdr -h MaildirBase $profile)
basedir=${basedir-$HOME/mail}
inbox_name=$(mhdr -h InboxName $profile)
[ -z "${inbox_name}" ] && inbox_name=INBOX
inbox=$(mhdr -h Inbox $profile)
[ -z "${inbox}" ] && inbox=${basedir}/${inbox_name}
editor_cmd=$(mhdr -h Editor $profile)
[ -z "${editor_cmd}" ] && editor_cmd=${EDITOR-${VISUAL-vi}}
EDITOR=${EDITOR-$editor_cmd}
mdopts=$(mhdr -h MdisplayOpts $profile)
synchost=$(mhdr -h SyncHost $profile)
synccmd=$(mhdr -h SyncCmd $profile)
[ -z "${synccmd}" ] && synccmd="rsync -azv"
syncrmt=$(mhdr -h SyncRemoteDir $profile)
[ -z "${syncrmt}" ] && syncrmt=$HOME
mairix=$(mhdr -h MairixCmd $profile)
[ -z "${mairix}" ] && mairix=mairix
index_opts=$(mhdr -h MairixIndexOpts $profile)
CMD=$(mhdr -h MBDefaultCmd $profile)
[ -z "$CMD" ] && CMD=minbox
shell_cmd=$(mhdr -h ShellEscapeCmd $profile)
[ -z "${shell_cmd}" ] && shell_cmd=${SHELL-/bin/sh}
rl_cmd=$(mhdr -h MBReadLineCmd $profile)
rl_from_profile=0
[ -n "${rl_cmd}" ] && rl_from_profile=1
[ -z "${rl_cmd}" ] && rl_cmd=rl
if [ $rl_from_profile -eq 0 ]; then
	rl_hist=$(mhdr -h MBHistoryFile $profile)
	[ -n "${rl_hist}" ] && rl_cmd="${rl_cmd} -F ${rl_hist}"
	rl_maxhist=$(mhdr -h MBHistoryMax $profile)
	[ -n "${rl_maxhist}" ] && rl_cmd="${rl_cmd} -X ${rl_maxhist}"
fi
rl_cmd="${rl_cmd} -C ${OUR_CMDLIST} -D ${basedir}"
quiet_start=$(mhdr -h MBStartQuiet $profile)
[ -z "${quiet_start}" ] && quiet_start=0

# parse command-line args
VERBOSE=0
f=
only_one=0
args=$(getopt nq1 $*)
if [ $? -ne 0 ]; then
	echo usage: $(basename $SCRIPT) [-nqv1] [folder [cmd...]]
	exit 1
fi
set -- $args
while [ $# -ne 0 ]; do
	case "$1" in
		-1) only_one=1; shift ;;
		-n) CMD=mnewbox; shift ;;
		-q) quiet_start=1; shift ;;
		-v) VERBOSE=1; shift ;;
		--) shift; break ;;
	esac
done
if [ $# -gt 0 ]; then
	f=$1
	shift
	[ $f = "-" ] && f=""
fi

# set FOLDER and CMD
[ -n "$f" ] && FOLDER=$f
[ -z "${FOLDER}" ] && FOLDER=${INBOX-$inbox_name}
new=
[ "${CMD}" = "mnewbox" ] && new='*'

verbose () {
	if [ $VERBOSE -ne 0 ]; then
		echo $@
	fi
}

export FOLDER # for subprocesses

# common back-end to mcom/mfwd/mrep
tmux_send () {
	my cmd args msgno fullcmd title
	cmd=$1
	shift
	case ${cmd} in
		mcom)
			fullcmd="${cmd} $*"
			title="compose"
			;;
		mfwd|mrep)
			args=$(set_args $*)
			msgno=$(tmux show-buffer)
			title="reply"
			[ ${cmd} = mfwd ] && titla="fwd"
			title="${title} ${msgno}"
			fullcmd="${cmd} ${args} -- ${msgno}"
			;;
	esac
	tmux new-window -n "[$title]" "echo ${fullcmd}; env EDITOR=$EDITOR ${fullcmd}; echo '[PRESS RETURN TO CLOSE]'; read"
}

reply () {
	tmux_send mrep $*
}

send () {
	tmux_send mcom $*
}

fwd () {
	tmux_send mfwd $*
}

# rescan current folder and display the current sequence
rescan () {
	my nothing afterargs
	nothing=$1
	shift
	afterargs="$*"
	[ -n "${CMD}" ] && {
		if [ ${nothing} = inbox ]; then
			FOLDER=${INBOX-$inbox_name}
		elif [ ${nothing} = cd ]; then
			[ -z "${afterargs}" ] && afterargs=${INBOX-$inbox_name}
			FOLDER=${afterargs}
		fi
		echo ${CMD} ${FOLDER}
		${CMD} ${FOLDER}
	}
}

# deal with [msgno] [args...]
# if our first arg looks like a number, set msgno/tmux-buffer
# and shift it out.
# return what is left
set_args () {
	my the_args
	the_args="$*"
	case ${the_args} in
		[0-9]*)
			set -- ${the_args}
			tmux set-buffer $1
			shift
			the_args="$*"
			;;
	esac
	echo ${the_args}
}

# like set_args but for the extract/mime/show cases msgno can be
# implicit, if first arg is numeric but within the range
# 1..$number_attachments of cur message, don't treat it as a msg#,
# treat it as attachment#
special_args () {
	my the_args cur natt
	cur=$(tmux show-buffer)
	the_args="$*"
	case $1 in
		[0-9]*)
			if [ -n "${cur}" ]; then
				natt=$(mshow -t ${cur} |tail -1 | \
					       awk -F: '{print $1}')
				if [ $1 -gt $natt ]; then
					tmux set-buffer $1
					shift
					the_args="$*"
				fi
				# else it is an attachment#, leave args alone
			else
				tmux set-buffer $1
				shift
				the_args="$*"
			fi
			;;
	esac
	echo ${the_args}
}

# search this script for hash-plus comments and display them in various ways
give_help () {
	my cmds cmd
	# get the list of commands for starters, alpha-sorted
	cmds=$OUR_CMDS
	case $1 in
		help)
			# if they give us a specific command find help for it
			# otherwise, dump all the help summaries (first lines)
			if [ -z "$2" ]; then
				for cmd in ${cmds}; do
					grep "#\+ $cmd " $SCRIPT | head -1 | \
						sed -e 's/^.*#\+ //'
				done
			else
				# print all the help for a specific command
				grep "#\+ $2 " $SCRIPT | \
					sed -e 's/^.*#\+ //' | head -1
				grep "#\+ $2 " $SCRIPT | \
					sed -e 1d -e "s/^.*#\+ $2 /    /" | fmt
			fi
			;;
		brief)
			echo "commands/topics:"
			echo ${cmds} | rs
			echo "type msg# / sel msg# w/mouse in tmux and use . to see in new pane"
			echo "use: brief for this short help again, help <topic> for longer help"
			echo "sigs: ^\ (QUIT) = cur folder status, ^C (INT) = quit gracefully"
			;;
		man)
			if [ -z "$2" ]; then
				echo "man what?"
			else
				man $2
			fi
			;;
	esac
}

usage () {
	echo "usage: $*"
}

# handle one command and optional args
process_command () {
	my nothing afterargs beforeargs cmd do_mscan tohost
	nothing=$1
	shift
	afterargs="$*"
	beforeargs=
	cmd="mdisplay ${mdopts}"
	do_mscan=
	case ${nothing} in
		reply|fwd|send) #+ reply [msgno] [mcom-opts] - reply to cur/given msg in new (tmux) window
			#+ fwd [msgno] [mcom-opts] - forward message
			#+ send [mcom-opts] - send new message, c.f. mcom(1)
			${nothing} ${afterargs}
			return
			;;
		mime|extract|headers) #+ mime [msgno] - display mime structure of msg
			#+ extract [msgno] part# - extract given part of msgno
			#+ extract if no msgno is given and part# is a valid
			#+ extract attachment# for the current message, a
			#+ extract single numeric arg is taken to be att#
			#+ headers [opts] [msgno] - dump headers of msg to stdout
			#+ headers other options to mshow(1) can precede the
			#+ headers optional msgno, so >headers -H   will show
			#+ headers all raw headers of the current message
			case ${nothing} in
				mime)
					cmd="mshow -t"
					afterargs=$(special_args ${afterargs})
					;;
				extract)
					cmd="mshow -x"
					afterargs=$(special_args ${afterargs})
					;;
				headers)
					cmd="mshow -q"
					beforeargs=$(special_args ${afterargs})
					afterargs=""
					;;
			esac
			;;
		mv|cp)	#+ mv [msgno...] dest-folder - move msg to given folder
			#+ mv if no messages are given the current msg is
			#+ mv assumed.  dest-folder can be a path relative to
			#+ mv your MaildirBase config setting.
			#+ mv If dest-folder does not end in /new or /cur it
			#+ mv is assumed you meant /new.
			#+ cp [msgno...] dest-folder - copy msg to given folder
			#+ cp if no messages are given the current msg is
			#+ cp assumed.  dest-folder can be a path relative to
			#+ cp your MaildirBase config setting.
			#+ cp If dest-folder does not end in /new or /cur it
			#+ cp is assumed you meant /new.
			if [ "$nothing" = "cp" ]; then
				cmd="mrefile -k"
			else
				cmd=mrefile
			fi
			afterargs=$(set_args ${afterargs})
			[ -z "${afterargs}" ] && {
				usage "${nothing} [msgno] dest-folder"
				return
			}
			afterargs="${basedir}/${afterargs}"
			do_mscan=mscan
			;;
		rm)	#+ rm msgno [msgno...] - remove indicated messages
			#+ rm we refuse to simply operate on the current
			#+ rm message so you can't so easily delete it
			if [ -z "${afterargs}" ]; then
				give_help help rm
			else
				echo mrm ${afterargs}
				mrm ${afterargs}
			fi
			return
			;;
		inc)	#+ inc [all|new] - incorporate new mail into cur (mark all read in folder)
			#+ inc We use the minc(1) program from mblaze(7) to
			#+ inc incorporate new mail in the current folder,
			#+ inc which many MUAs call mark-all-as-read.
			#+ inc If we were in "new" mode (c.f. the new/all
			#+ inc commands) then we normall switch to "all"
			#+ inc mode after running minc.  If our optional
			#+ inc argument is "new", then we stay in "new" mode
			#+ inc instead.  If our optional argument is "all"
			#+ inc then instead of minc, we run the mincall
			#+ inc script to incorporate all new mail in all
			#+ inc folders.
			if [ -z "${afterargs}" -o "${afterargs}" = new ]; then
				echo minc ${FOLDER}
				minc ${basedir}/${FOLDER} | mscan
				if [ -n "${new}" -a -z "${afterargs}" ]; then
					new=
					CMD=minbox
				elif [ "${afterargs}" = new ]; then
					new='*'
					CMD=mnewbox
				fi
			elif [ "${afterargs}" = all ]; then
				mincall
			else
				usage "inc what?"
			fi
			return
			;;
		decrypt) #+ decrypt [msgno] - run mdecrypt on message
			cmd=mdecrypt
			afterargs=$(set_args ${afterargs})
			;;
		cat)	#+ cat [msgno] - dump raw message to stdout
			cmd=mshow
			afterargs=$(set_args ${afterargs})
			;;
		quit)	#+ quit - exit program
			exit 0
			;;
		ls|cd|inbox)
			#+ ls [slice] - (re)list current folder
			#+ ls if the optional slice is specified, only that slice of the
			#+ ls folder (new or cur) will be displayed. if it is a positive
			#+ ls number, that many from the front are displayed. if it is a
			#+ ls negative number, that many from the end. if it is a range
			#+ ls of numbers separated by a dash, e.g. 1-20, then that range
			#+ ls of messages is displayed. the setting of a slice is sticky,
			#+ ls meaning it is remembered and carries over to other commands
			#+ ls like new and all.
			#+ cd folder - switch to different folder
			#+ inbox - switch to in-box and list
			case "${afterargs}" in
				[0-9]*)
					MB_HEAD=${afterargs}
					export MB_HEAD
					unset MB_TAIL MB_MID
					;;
				-[0-9]*)
					MB_TAIL=${afterargs}
					export MB_TAIL
					unset MB_HEAD MB_MID
					;;
				[0-9]*-[0-9]*)
					MB_MID=${afterargs}
					export MB_MID
					unset MB_HEAD MB_TAIL
					;;
				-)
					unset MB_HEAD MB_TAIL MB_MID
					afterargs=""
					;;
			esac
			rescan ${nothing} ${afterargs}
			return
			;;
		all|cur|new) #+ cur [slice] - switch from new to cur in the current Maildir
			#+ cur the optional slice has the same syntax as for the ls
			#+ cur command, so: cur -10 displays the last ten messages in cur
			#+ all [slice] - alias for cur
			#+ new [slice] - switch from cur to new in the current Maildir
			#+ new the optional slice has the same syntax as for the ls
			#+ new command, so: new -10 shows the last ten messages in new
			if [ ${nothing} = "new" ]; then
				CMD=mnewbox
				new='*'
			else
				CMD=minbox
				new=
			fi
			case "${afterargs}" in
				[0-9]*)
					MB_HEAD=${afterargs}
					export MB_HEAD
					unset MB_TAIL MB_MID
					;;
				-[0-9]*)
					MB_TAIL=${afterargs}
					export MB_TAIL
					unset MB_HEAD MB_MID
					;;
				[0-9]*-[0-9]*)
					MB_MID=${afterargs}
					export MB_MID
					unset MB_HEAD MB_TAIL
					;;
				-)
					unset MB_HEAD MB_TAIL MB_MID
					afterargs=""
					;;
			esac
			rescan ${nothing} ${afterargs}
			return
			;;
		spam)	#+ spam [msgno] - run message through mrespam
			if [ -n "${afterargs}" ]; then
				echo mrespam ${afterargs}
				mrespam ${afterargs}
				return
			fi
			cmd=mrespam
			;;
		unspam) #+ unspam [msgno] - run message through munspam
			if [ -n "${afterargs}" ]; then
				echo munspam ${afterargs}
				munspam ${afterargs}
				return
			fi
			cmd=munspam
			;;
		grep)	#+ grep args... - run magrep args on current folder,
			#+ grep displays results on stdout, no change to current seq.
			#+ grep magrep cheat sheet: header:regexp find messages where
			#+ grep header matches regexp, /:regexp find messages where
			#+ grep body matches regexp. only one regexp-style arg is
			#+ grep allowed, subsequent args are an optional message seq.
			#+ grep by default the current msgseq is searched, c.f.
			#+ grep magrep(1) et al.
			magrep ${afterargs} | mthread | mscan
			return
			;;
		restrict) #+ restrict args - like grep but sets current msgseq
			#+ restrict sets the current msgseq to matching messages,
			#+ restrict same syntax as the grep command
			magrep ${afterargs} | mthread | mseq -S | mscan
			return
			;;
		search) #+ search mairix-expr - run mairix on args and cd into Search
			#+ search mairix dumps search results into a folder named Search
			#+ search via hardlinks, by default it is overwritten every search
			#+ search use -a to append results. mairix-expr cheat-sheet:
			#+ search t:to c:cc f:from s:subj m:msgid b:body d:date1-date2
			#+ search z:lowsize-hisize n:attachment F:flags
			#+ search also can be combined e.g. tc:to+from bs:body+subj
			#+ search a:addr is short for tcf:addr (to/cc/from)
			${mairix} -H ${afterargs}
			CMD=minbox
			new=''
			rescan cd Search
			return
			;;
		find)	#+ find mairix-expr - like search but dump excerpts to stdout
			${mairix} -x ${afterargs}
			return
			;;
		index)	#+ index - run mairix (or whatever) to (re)index your mail
			#+ index runs whatever indexer you have configured (def: mairix)
			#+ index to (re)index your mail for search, default arg is -p.
			#+ index the mailcheck script that comes with mb also can do
			#+ index this automatically as mail is fetched.
			echo ${mairix} ${index_opts}
			${mairix} ${index_opts}
			return
			;;
		dirs)	#+ dirs - list Maildirs with new mail in them
			mnewdirs | rs
			return
			;;
		sync)	#+ sync [host] - sync maildir to another host
			#+ sync sync mail tree to another host; if no
			#+ sync host is given, the default from your
			#+ sync SyncHost preference is used.
			tohost="${afterargs}"
			[ -z "${tohost}" ] && tohost=${synchost}
			echo ${synccmd} ${basedir} ${tohost}:${syncrmt}
			${synccmd} ${basedir} ${tohost}:${syncrmt}
			return
			;;
		help|brief|man) #+ help [cmd] - list commands and what they do
			#+ brief [cmd] - print a brief usage summary/command list
			#+ man [args] - use the system man(1) command on args
			give_help ${nothing} ${afterargs}
			return
			;;
		prompt)
			#+ prompt - not actually a command, just doc :-)
			#+ prompt the mb prompt has the following parts:
			#+ prompt the name of the folder you are viewing,
			#+ prompt a star if you are in new instead of cur,
			#+ prompt and any slice you have restricted to via
			#+ prompt e.g. the new, cur or ls commands and a
			#+ prompt greater-than sign, e.g. INBOX*-10>
			#+ prompt means you are in your inbox viewing
			#+ prompt only the last ten messages in new
			give_help help prompt
			return
			;;
		[0-9]*) tmux set-buffer ${nothing}
			;;
		[a-zA-Z]*)
			if [ -d ${basedir}/${nothing} ]; then
				rescan cd ${nothing}
				return
			fi
			usage "not recognized: ${nothing}"
			give_help brief
			return
			;;
		.) ;;	#+ . - a single dot displays the current message
		!*)	#+ ! cmd ... - run a shell command
			#+ ! this is an ancient unix tradition
			nothing=$(echo ${nothing} | sed -e 's/^!//')
			echo ${shell_cmd} -c "${nothing} ${afterargs}"
			${shell_cmd} -c "${nothing} ${afterargs}"
			return
			;;
	esac
	msgno=$(tmux show-buffer)
	if [ -n "${msgno}" ]; then
		f=$(mpick ${msgno} 2>/dev/null)
		verbose "[msgno: ${msgno} .. $f]"
		if [ -n "$f" ]; then
			echo ${cmd} ${beforeargs} ${msgno} ${afterargs}
			if [ -n "${do_mscan}" ]; then
				${cmd} ${beforeargs} ${msgno} ${afterargs} | \
					${do_mscan}
			else
				${cmd} ${beforeargs} ${msgno} ${afterargs}
			fi
		fi
	fi
}

spew_status () {
	echo ''
	mlist -i ${basedir}/${FOLDER}
	rm -f $MBLAZE/seq-
}

slice () {
	if [ -n "$MB_HEAD" ]; then
		echo +${MB_HEAD}
	elif [ -n "$MB_TAIL" ]; then
		echo ${MB_TAIL}
	elif [ -n "$MB_MID" ]; then
		echo :${MB_MID}
	fi
}

msgno=
if [ $quiet_start -eq 0 ]; then
	${CMD} ${FOLDER}
	echo "folder: ${FOLDER}, cmd: ${CMD}, editor: ${EDITOR}"
	give_help brief
fi
if [ $# -gt 0 ]; then
	process_command $*
	[ $only_one -ne 0 ] && exit 0
fi

trap 'spew_status; echo "("quit" or EOF to quit)"' QUIT INT
trap 'spew_status; echo "[TERM]"; quitting=1' TERM

quitting=0
while [ $quitting -eq 0 ]; do
	line=$(${rl_cmd} mb "${FOLDER}${new}$(slice)> ")
	status=$?
	if [ $status -ne 0 ]; then
		if [ $status -lt 100 ]; then
			echo "  [QUIT]"
			quitting=1
		fi
	elif [ -n "${line}" ]; then
		set -- $line
		process_command $*
	fi
done

exit 0