#!/bin/sh

set -e

. /usr/share/debconf/confmodule

CONFIGDIR="/etc/silcd"
CONFIGFILE="$CONFIGDIR/silcd.conf"
IPCONFIGFILE="$CONFIGDIR/silcd-primary-ip.conf"
ADMINCONFIGFILE="$CONFIGDIR/silcd-admin.conf"
DEFAULT_CONFIGDIR="/usr/share/doc/silcd/examples"
DEFAULT_CONFIGFILE="$DEFAULT_CONFIGDIR/silcd.conf.default.gz"
DEFAULT_IPCONFIGFILE="$DEFAULT_CONFIGDIR/silcd-primary-ip.conf.default"
DEFAULT_ADMINCONFIGFILE="$DEFAULT_CONFIGDIR/silcd-admin.conf.default"

read_config() {
    PARAMETER="$1"
    sed -n -e "s/^[^#]*$PARAMETER  *=  *\"\(\(\\\.\|[^\"]\)*\)\".*$/\1/p" \
    	"$CONFIGFILE" | sed -e 's/\\//g'
}

if [ -e "$CONFIGFILE" ]; then
    PUBLIC_KEY="$(read_config PublicKey)"
    PRIVATE_KEY="$(read_config PrivateKey)"
else
    PUBLIC_KEY="/etc/silcd/silcd.pub"
    PRIVATE_KEY="/etc/silcd/silcd.prv"
fi

retrieve_debconf_answers() {
    db_get silcd/server-name
    SERVER_NAME="$RET"
    db_get silcd/host-name
    HOST_NAME="$RET"
    db_get silcd/real-name
    REAL_NAME="$RET"
    db_get silcd/email
    EMAIL="$RET"
    db_get silcd/organization
    ORGANIZATION="$RET"
    db_get silcd/country
    COUNTRY="$RET"
    db_get silcd/admin-nick
    ADMIN_NICK="$RET"
    db_get silcd/admin-passphrase
    ADMIN_PASSPHRASE="$RET"
}

rfc2253ize() {
    # We espace: symbols ,w+"\<> and spaces at end and begining
    echo "$1" | sed -e 's/[,;+"\\<>]/\\\0/g;s/ $/\\\0/g;s/^[ #]/\\\0/g'
}

create_key_pair() {
    local tmpdir

    retrieve_debconf_answers

    if [ -z "$SERVER_NAME" -o -z "$HOST_NAME" ]; then
        # Don't create keypair
        return
    fi

    IDENTIFIER="UN=$(rfc2253ize "SERVER_NAME"), HN=$(rfc2253ize "$HOST_NAME")"
    if [ -n "$REAL_NAME" ]; then
        IDENTIFIER="$IDENTIFIER, RN=$(rfc2253ize "$REAL_NAME")"
    fi
    if [ -n "$EMAIL" ]; then
        IDENTIFIER="$IDENTIFIER, E=$(rfc2253ize "$EMAIL")"
    fi
    if [ -n "$COUNTRY" ]; then
        IDENTIFIER="$IDENTIFIER, C=$(rfc2253ize "$COUNTRY")"
    fi

    tmpdir=$(mktemp -d -t silcd.XXXXXX)
    chmod 700 "$tmpdir"
    silcd --create-key-pair="$tmpdir" --identifier="$IDENTIFIER"
    mkdir -p "$(dirname "$PUBLIC_KEY")" "$(dirname "$PRIVATE_KEY")"
    mv -f "$tmpdir/silcd.pub" "$PUBLIC_KEY"
    mv -f "$tmpdir/silcd.prv" "$PRIVATE_KEY"
    chmod 0600 "$PRIVATE_KEY"
    rmdir "$tmpdir"
}

change_setting() {
    FILE="$1"
    shift
    KEY="$1"
    shift
    VALUE="$*"
 
    VALUE="$(echo "$VALUE" | sed -e 's,/,\\/,g;s,",\\\\",g')"
    sed -i -e "s/\([^#]*$KEY  *=  *\"\)[^\"]*\(\"\)/\1$VALUE\2/" "$FILE"
}

update_config_file() {
    retrieve_debconf_answers
    IP="$(getent hosts "$HOST_NAME" | awk '{print $1}')" 

    # silcd.conf
    TEMPFILE=$(tempfile)
    zcat "$DEFAULT_CONFIGFILE" > "$TEMPFILE"

    change_setting "$TEMPFILE" ServerType "$SERVER_NAME"
    change_setting "$TEMPFILE" hostname "$HOST_NAME"
    change_setting "$TEMPFILE" Admin "$REAL_NAME"
    change_setting "$TEMPFILE" AdminEmail "$EMAIL"
    change_setting "$TEMPFILE" Location "$COUNTRY"

    ucf --debconf-ok "$TEMPFILE" "$CONFIGFILE"

    rm -f "$TEMPFILE"

    # silcd-primary-ip.conf
    TEMPFILE=$(tempfile)
    cat "$DEFAULT_IPCONFIGFILE" > "$TEMPFILE"

    change_setting "$TEMPFILE" ip "$IP"

    ucf --debconf-ok "$TEMPFILE" "$IPCONFIGFILE"

    rm -f "$TEMPFILE"

    # silcd-admin.conf
    TEMPFILE="$(tempfile)"
    cat "$DEFAULT_ADMINCONFIGFILE" > "$TEMPFILE"

    change_setting "$TEMPFILE" Nick "$ADMIN_NICK"
    change_setting "$TEMPFILE" Passphrase "$ADMIN_PASSPHRASE"

    ucf --debconf-ok "$TEMPFILE" "$ADMINCONFIGFILE"

    rm -f "$TEMPFILE"
}

case "$1" in
    configure)
        if [ "$DEBCONF_RECONFIGURE" = "1" ] ||
           ! [ -e "$PUBLIC_KEY" -a -e "$PRIVATE_KEY" ]; then
            create_key_pair
        fi
        update_config_file
        ;;

    reconfigure)
        create_key_pair
        update_config_file
        ;;

    abort-upgrade|abort-remove|abort-deconfigure)
        ;;

    *)
        echo "postinst called with unknown argument \`$1'" >&2
        exit 1
        ;;
esac

# We are going to start a daemon, so we need to be debconf clean.
db_stop

#DEBHELPER#

exit 0

#vim: et sw=4