#!/bin/sh -ue
#
# Read a mail folder with mutt.
#	- Cameron Simpson <cs@zip.com.au>
#

set -ue

: ${MAILHOMEHOST:=$HOMEHOST}
: ${DISPLAY:=''}
: ${LOGDIR:=$HOME/var/log}
: ${ALERTLOG:=$LOGDIR/alert}
: ${MAILDIR:=$HOME/mail}
: ${MAIL_EXPIRE_FORMAT:='%Y'}           # versus, say, %Y-%m

needhost "$MAILHOMEHOST@$SYSTEMID" \
|| { rhost=$SYSTEMID    # sshto clause to deliver to system home host
     qargv=`shqstr + -s "$@"`
     set -x
     exec envssh -t "$rhost" "$qargv"
   }

cmd=$0
usage="Usage: $0 [+a] [+s] [+t] [-f] [some-mutt-options...] [mutt-folder]"

mfolder=+me
delay=5
muttopts=
anyhost=
use_term=	## 1; case "$DISPLAY" in localhost:[1-9]*) use_term= ;; esac
use_screen=
preshcmd=:
postshcmd=:
termopts='-g M'

badopts=
while [ $# -gt 0 ]
do
  case $1 in
    +a)		termopts="$termopts $1" ;;
    -s)		use_screen=1 ;;
    +s)		use_screen= ;;
    +t)		use_term= ;;
    -f)		anyhost=1 ;;
    -[nR])	muttopts="$muttopts $1" ;;
    -[em])	muttopts="$muttopts $1 "`shqstr "$2"`; shift ;;
    --pre=*)	preshcmd=`expr "x$1" : 'x--pre=\(.*\)'` ;;
    --post=*)	postshcmd=`expr "x$1" : 'x--post=\(.*\)'` ;;
    --)		shift; break ;;
    -?*|+?*)	echo "$cmd: unrecognised option: $1" >&2; badopts=1 ;;
    *)		break ;;
  esac
  shift
done

if [ $# -gt 0 ]
then
  case $1 in
    /*|.|./*|..|../*)
    		mfolder=$1 ;;
    +*)		mfolder=$1 ;;
    imap:*|imaps:*)
    		mfolder=$1 anyhost=1 ;;
    *?.?*)	mfolder=nntp://$NNTPSERVER/$1 anyhost=1 ;;
    *)		mfolder=+$1 ;;
  esac
  shift
  [ $# = 0 ] || { echo "$cmd: extra arguments: $*" >&2; badopts=1; }
else
  # hack to clear my alert window when I view my default folder
  ( clear >>"$ALERTLOG" ) &
fi

[ $badopts ] && { echo "$usage" >&2; exit 2; }

fpath=`mailfolderpath "$mfolder"` || exit 1
muttcmd="$HOME/bin-local/mutt -f '$mfolder' -e 'fcc-hook . $mfolder' $muttopts"

# where to take copies - presumes sendmail=sendmesg-fcc in muttrc
SENDMESG_FCC="$fpath +spool-out"
export SENDMESG_FCC

if [ -z "$fpath" ]
then
  fbase=misc
else
  fbase=`basename "$fpath"`
  ismaildir "$fpath" \
  || ismhdir "$fpath" \
  || { echo "$cmd: $fpath: not Maildir or MH folder" >&2
       exit 1
     }

  mutthcache=$HOME/var/mutt/header-cache/$fbase
  { needdir "$mutthcache" \
    && muttcmd="$muttcmd -e 'set header_cache=$mutthcache'"
  } || :

  fmuttrc=$fpath/.muttrc
  [ ! -s "$fmuttrc" ] || muttcmd="$muttcmd -e 'source $fmuttrc'"

  fpremutt=$fpath/.preshcmd
  [ ! -s "$fpremutt" ] || preshcmd="$preshcmd; . $fpremutt"

  fpostmutt=$fpath/.postshcmd
  [ ! -s "$fpostmutt" ] || postshcmd="$postshcmd; . $fpostmutt"
fi

CURRENT_FOLDER=$fpath
DELETE_FOLDER=$MAILDIR/OLD/`date "+$MAIL_EXPIRE_FORMAT"`/$fbase
export DELETE_FOLDER
export CURRENT_FOLDER DELETE_FOLDER
maildir "$DELETE_FOLDER"

set -- sh -c "exec $muttcmd"
[ $use_screen ] && set -- scr "MUTT_$mfolder" "$@"
[ $use_term   ] && set -- term -j email $termopts -n "mutt $mfolder" "$@"

[ -z "$preshcmd" ] || eval "$preshcmd"
"$@"
xit=$?
[ -z "$postshcmd" ] || eval "$postshcmd" || xit=1

exit $xit