#!/bin/bash
# 
# Copyright (C) 2002 Laird Breyer
#  
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
# 
# Author:   Laird Breyer <laird@lbreyer.com>
#
# IMPLEMENTATION NOTES
#
# This script follows the mailcross testsuite interface
# requirements. Type man mailcross for details.
#
# The script accepts one of more commands on the command line,
# and may read STDIN and write STDOUT as follows:
#
# If $1 == "filter":
# In this case, a single email is expected on STDIN,
# and a list of category filenames is expected in $2, $3, etc.
# The script writes the category name corresponding to the 
# input email on STDOUT.
#
# If $1 == "learn":
# In this case, a standard mbox stream is expected on STDIN,
# while a suitable category file name is expected in $2. No output
# is written to STDOUT.
#
# If $1 == "clean":
# In this case, a directory is expected in $2, which is examined
# for old database information. If any old databases are found, they
# are purged or reset. No output is written to STDOUT.
#
# If $1 == "describe":
# In this case, STDIN and the command line are ignored. A single
# line is written on STDOUT, describing the filter functionality.
#
# If $1 == "bootstrap":
# In this case, the current script is copied to the directory $2,
# provided the classifier we're wrapping exists on the system.
#

QSF="qsf"

case "$1" in
    filter)
	shift
	CATEGORY=`basename $1`
	DBPATH=`dirname $1`
	$QSF -d "${DBPATH}/qsfdb" -t
	if [ "$?" = "0" ]; then
	    echo "notspam"
	else
	    echo "spam"
	fi
	;;
    learn)
	shift
	CATEGORY=`basename $1`
	DBPATH=`dirname $1`
	# unfortunately, qsf doesn't have an interface for
	# training a single category at a time
	# we save a full mbox and feed it at a later invocation
	cat > "${DBPATH}/${CATEGORY}_qsf"
	if [ -e "${DBPATH}/spam_qsf" -a -e "${DBPATH}/notspam_qsf" ]; then
	    $QSF -d "${DBPATH}/qsfdb" -T "${DBPATH}/spam_qsf" "${DBPATH}/notspam_qsf"
	    rm -f "${DBPATH}spam_qsf.gz" "${DBPATH}notspam_qsf"
	fi
	;;
    clean)
	shift
	find "$1" -name "qsfdb" -exec rm {} \;
	find "$1" -name "*_qsf" -exec rm {} \;
	find "$1" -name "*.tmp" -exec rm {} \;
	;;
    describe)
	VER="(unavailable?)"
	if [ -n "`which $QSF`" ] ; then
	    VER=`$QSF -V | head -1 | sed -e 's/qsf //' -e 's/ -.*//'`
	fi
	echo "qsf $VER with default options"
	;;
    bootstrap)
	if [ -d "$2" ] ; then
            if [ -n "`which $QSF`" ] ; then
		echo "selecting $0"
		cp "$0" "$2"
		echo -e "\tqsf is hard-coded for use only with exactly"
		echo -e "\ttwo categories named 'spam' and 'notspam'."
	    else
		echo "qsf appears to be missing"
            fi
	else
	    echo "bad target directory $2"
	fi
	;;
    toe)
	ME="$0"
	shift
	TRUECAT="$1"
	DBPATH=`dirname $1`
	shift
	cat > "$TEMPDIR/mailtoe.tmp"
	VERDICT=`cat "$TEMPDIR/mailtoe.tmp" | "$ME" filter "$@"`
	if [ "x$VERDICT" != "x`basename $TRUECAT`" ] ; then
	    if [ "$VERDICT" = "spam" ] ; then
		cat "$TEMPDIR/mailtoe.tmp" | $QSF -M -d "${DBPATH}/qsfdb"
	    else
		cat "$TEMPDIR/mailtoe.tmp" | $QSF -m -d "${DBPATH}/qsfdb"
	    fi
	fi
	echo -ne "$VERDICT"
	;;
    foot)
	ME="$0"
	shift
	TRUECAT="$1"
	DBPATH=`dirname $1`
	shift
	cat > "$TEMPDIR/mailfoot.tmp"
	VERDICT=`cat "$TEMPDIR/mailfoot.tmp" | "$ME" filter "$@"`
	if [ "`basename $TRUECAT`" = "spam" ] ; then
	    cat "$TEMPDIR/mailfoot.tmp" | $QSF -m -d "${DBPATH}/qsfdb"
	else
	    cat "$TEMPDIR/mailfoot.tmp" | $QSF -M -d "${DBPATH}/qsfdb"
	fi
	echo -ne "$VERDICT"
	;;
esac