#!/bin/bash
# Copyright (C) 2009-2012 Centro de Computacao Cientifica e Software Livre
# Departamento de Informatica - Universidade Federal do Parana - C3SL/UFPR
#
# This file is part of collect-agent
#
# collect-agent 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
# USA.

# This script collects the machine network usage, generating and sending an XML
# to the server. Exit status:
#
# 0 - Success
# 1 - Error while loading configuration
# 2 - INEP not configured
# 3 - XML filename not defined
# 4 - Client not found or without execution permission
# 5 - Error while collecting network usage data
# 6 - Error while executing the client

# ------------------------------------------------------------------------------
# Function: elapsedTime
# Verify if $DELAY seconds have elapsed since agent last execution.
# Return true or false.
function elapsedTime()
{
    test -f "${NETLASTEXEC}" || return 0

    atSeconds=$(date +%s)
    oldSeconds=$(cat ${NETLASTEXEC})

    (( (${atSeconds}-${oldSeconds}) >= ${DELAY} ))

    return $?
}

# ------------------------------------------------------------------------------
# Function: clientExec
# Execute client sender with all necessary parameters.
# The parameters are obtained from the global variables.
function clientExec()
{
    date +"%F %T - Sending network usage data to the server."

    ${CLIENT} $*
    error=$?

    if test ${error} -ne 0; then
        date +"%F %T - ERROR: while sending network usage data to the server."
        return ${error}
    fi
}

# ------------------------------------------------------------------------------
export PREFIX="$(dirname $(readlink -f $0))"
source ${PREFIX}/load-config.sh || exit 1
PREVIOUS_TRAFFIC="${PREFIX}/net/previous"

exec >> ${LOGFILE} 2>&1

date +"%F %T - Start of network usage execution."

# Check if inep file exists and is configured
if ! test -f ${CLIENTCONFDIR}/inep -a -n "$(cat ${CLIENTCONFDIR}/inep \
                                            2> /dev/null)"; then
    date \
    +"%F %T - INEP not found in ${CLIENTCONFDIR}/inep, waiting configuration."
    exit 2
fi

# Collect and send system data if elapsed enough time or if it's the first
# execution of the agent
if elapsedTime && test -d "${PREVIOUS_TRAFFIC}"; then
    if test -z "${NETXMLFILENAME}"; then
        printf "ERROR: Net XML filename not defined at configuration file.\n"
        exit 3
    else
        # Create "data" directory if it does not exist
        mkdir -p $(dirname $NETXMLFILENAME)
    fi
    if test ! -x "${CLIENT}"; then
        printf "ERROR: Client not found or without execution permission.\n"
        printf "${SCRIPTPATH} finished.\n"
        exit 4
    fi

    # Collect system data
    if ! ${XMLPARSER} "${NETSCRIPTSDIR}" "${NETXMLFILENAME}"; then
        date +"%F %T - ERROR: while collecting network usage data."
        exit 5
    fi

    date +"%F %T - New network usage data collected."
    if ! clientExec --net-usage; then
        exit 6
    fi
	
	# Remove data already sent
	rm -rf ${PREVIOUS_TRAFFIC}
	
    # Record the current execution time to be used by elapsedTime()
    date +%s > ${NETLASTEXEC}
fi

date +"%F %T - Network usage terminated successfully."
exit 0