#!/bin/bash
# -*- coding: utf-8 -*-
###########################################################################
#                                                                         #
#  envbot - an IRC bot in bash                                            #
#  Copyright (C) 2007-2008  Arvid Norlander                               #
#                                                                         #
#  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 3 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, see <http://www.gnu.org/licenses/>.  #
#                                                                         #
###########################################################################
#---------------------------------------------------------------------
## A transport module using /dev/tcp
#---------------------------------------------------------------------

# A list of features supported
# These are used: ipv4, ipv6, ssl, nossl, bind
transport_supports="ipv4 ipv6 nossl"

# Check if all the stuff needed to use this transport is available
# Return status
#   0 yes
#   1 no
transport_check_support() {
	# If anyone can tell me how to check if /dev/tcp is supported
	# without trying to make a connection (that could fail for so
	# many other reasons), please contact me.
	echo "NOTE: It is possible that this transport is not supported on your system"
	echo "      However, there is no way it can be checked except trying to connect."
	echo "      If you see an error below try netcat or socat transport instead."
	return 0
}

# Try to connect
# Parameters
#   $1 hostname/IP
#   $2 port
#   $3 If 1 use SSL. If the module does not support it, just ignore it.
#   $4 IP to bind to if any and if supported
#      If the module does not support it, just ignore it.
# Return status
#   0 if Ok
#   1 if connection failed
transport_connect() {
	exec 3<&-
	exec 3<> "/dev/tcp/${1}/${2}"
	time_get_current 'transport_lastvalidtime'
}

# Called to close connection
# No parameters, no return code check
transport_disconnect() {
	exec 3<&-
	# To force code to consider this disconnected.
	transport_lastvalidtime=0
}

# Return status
#   0 If connection is still alive
#   1 If it isn't.
transport_alive() {
	local newtime=
	time_get_current 'newtime'
	(( newtime - transport_lastvalidtime > 300 )) && return 1
	return 0
}

# Return a line in the variable line.
# Return status
#   0 If Ok
#   1 If connection failed
transport_read_line() {
    while true
    do
	ze_length="$( wc -l '/tmp/un-provoked-message-store' 2> /dev/null )"

	if [[ -r /tmp/un-provoked-message-store ]] &&
	     [[ -w /tmp/un-provoked-message-store ]] && (( ${ze_length%% *} ))
	then
	    read -r line < /tmp/un-provoked-message-store
	    line=':'${INJECT_NICK}'!~user@2001:ba8:1f1:f216::5 PRIVMSG #parabola :'"${line}"

	    # remove the top line of the file
	    if (( ${ze_length%% *} < 2 ))
	    then
		echo -n > /tmp/un-provoked-message-store
	    else
		tail -n +2 /tmp/un-provoked-message-store |
		sponge /tmp/un-provoked-message-store
	    fi

	    break
	else
	    read -t 5 -ru 3 line
	    the_return_code="${?}"
	    (( the_return_code == 0 )) && break
	    (( the_return_code > 128 )) && continue
	    [[ "${the_return_code}" -ne 0 ]] && return
	fi
    done

    time_get_current 'transport_lastvalidtime'
    line=${line//$'\r'/}
}


# Send a line
# Parameters
#   $* send this
# Return code not checked.
transport_write_line() {
	echo "$*" >&3
}