#!/bin/bash

# Author: gilbertas matusevicius
# Kolmisoft, 2015

. /usr/src/m2/framework/bash_functions.sh
. /usr/src/m2/framework/settings.sh

script_log="/var/log/m2/m2_pcap_control.log"
pcap_dir="/var/log/m2/pcap"
pcap_size="256MiB"
pcap_binary="/usr/src/m2/scripts/pcapsipdump"
pcap_output=""


get_first_net_interface()
{ 
    # Set variable default_interface to first non loopback interface and return 0
    # If ip command is not found or do not return anything, default_interface is empty and return value is 1
    default_interface=""
    /sbin/ip link show &> /dev/null
    if [ $? != 0 ]; then
         return 1;
    fi
    
    default_interface=$(/sbin/ip link show | grep -E '^[[:digit:]]+:' | awk -F':' '{print $2}' | sed 's/\s//g' | grep -vE '^lo$' | head -n1)
    if [ -z $default_interface ]; then
        return 1
    else 
        return 0
    fi
}

retrieve_email_settings()
{
    mysql_connect_data_v2 &> /dev/null
    if [ "$?" != "0" ]; then
        echo "[WARNING] $(date) Failed to retrieve database connection details. Will not send email" 
        return 1;
    fi
    
    
    Email_Smtp_Server=$(/usr/bin/mysql -h "$DB_HOST" -u "$DB_USERNAME" --password=$DB_PASSWORD "$DB_NAME" --disable-column-names -B -e 'SELECT value FROM conflines WHERE owner_id = 0 AND name = "Email_Smtp_Server"')    
    Email_Login=$(/usr/bin/mysql -h "$DB_HOST" -u "$DB_USERNAME" --password=$DB_PASSWORD "$DB_NAME" --disable-column-names -B -e 'SELECT value FROM conflines WHERE owner_id = 0 AND name = "Email_Login"')    
    Email_Password=$(/usr/bin/mysql -h "$DB_HOST" -u "$DB_USERNAME" --password=$DB_PASSWORD "$DB_NAME" --disable-column-names -B -e 'SELECT value FROM conflines WHERE owner_id = 0 AND name = "Email_Password"')    
    Email_from=$(/usr/bin/mysql -h "$DB_HOST" -u "$DB_USERNAME" --password=$DB_PASSWORD "$DB_NAME" --disable-column-names -B -e 'SELECT value FROM conflines WHERE owner_id = 0 AND name = "Email_from"')    
    Email_port=$(/usr/bin/mysql -h "$DB_HOST" -u "$DB_USERNAME" --password=$DB_PASSWORD "$DB_NAME" --disable-column-names -B -e 'SELECT value FROM conflines WHERE owner_id = 0 AND name = "Email_port"')    
         
    if [ "$Email_Smtp_Server" == "localhost" ]; then
        echo "[WARNING] $(date) smtp server is localhost. Will not send email" 
        return 1
    fi 
    
    return 0
}

read_m2_pcap_settings

if [ $PCAP_ENABLED == "0" ]; then
    echo "$(date) [WARNING] pcap is disabled. Will not run pcapsipdump command!" 
    exit 1
fi

if [ $PCAP_BUFFER_SIZE != "-1" ]; then
    pcap_size="$PCAP_BUFFER_SIZE"
fi

if [ $PCAP_LISTENING_NET_INTERFACE == "-1" ] || [ $PCAP_LISTENING_NET_INTERFACE == "default" ] || [ -z $PCAP_LISTENING_NET_INTERFACE ]
then
    get_first_net_interface 
    if [ $? != 0 ]; then
        pcap_interface="eth0"   
        echo "$(date) [WARNING] cannot get default interface, I will try to use $pcap_interface"
    else
        pcap_interface="$default_interface"
        echo "$(date) [NOTICE] using default interface $pcap_interface" 
    fi
else
    pcap_interface="$PCAP_LISTENING_NET_INTERFACE"
    echo "$(date) [NOTICE] using interface  $pcap_interface" 
fi

if ! [ -f $pcap_binary ]; then
   echo "$(date) [WARNING] pcapsipdump binary  $pcap_binary is not found. Updating scripts directory"
   svn update /usr/src/m2/scripts
fi



pcap_command="$pcap_binary -U -i $pcap_interface -d $pcap_dir -v 1 -B $pcap_size -R none"


sleep 5;

if ! ps aux | grep -v 'grep' | grep -Fqi pcapsipdump
then
    echo "$(date) [WARNING] pcapsipdump is not running. Enabling it"
    $pcap_command
else 
    echo "$(date) [NOTICE] pcapsipdump is running..."
    exit 1;
fi

sleep 5;
# Check again

if ! ps aux | grep -v 'grep' | grep -Fqi pcapsipdump
then
    echo "$(date) [WARNING] pcapsipdump is not running. Trying again"
    pcap_output=$($pcap_command 2>&1)
else
    echo "$(date) [NOTICE] pcapsupdump is running..."
    exit 1;
fi

sleep 5;

if ! ps aux | grep -v 'grep' | grep -Fqi pcapsipdump; then
    echo "$(date) [ERROR] pcapsipdump cannot be started. Preparing to send notification email to support"
    
    
    if grep -Fqi 'Email sending trigerred!' $script_log; then
        echo "$(date) [WARNING] Today email sending was already trigered. Will not send email today"
        exit 1
    fi
    
    retrieve_email_settings
    if [ "$?" != "0" ]; then
        echo "$(date) [ERROR] Cannot get email settings or settings are incorrect. I will NOT send email" 
        exit 1;
    fi
    
    echo "$date [WARNING] Email sending trigerred!"
    
    client_tag=$(grep 'ExceptionNotifier_email_prefix' /home/m2/config/environment.rb | awk -F'=' '{print $2}')
    ifconfig_output=$(/sbin/ifconfig)
    external_ip=$(curl showip.net)
    
#here documents don't like indentation
read -r -d '' email_output <<  EOF
Pcap command output:
$pcap_output
--------------
Client tag:
$client_tag
---------------
External IP ( curl showip.net)
$external_ip
----------------
ifconfig command output:
$ifconfig_output
EOF

    
    if [ "$Email_Login" == "" ] && [ "$Email_Password" == "" ]
    then
        /usr/local/m2/sendEmail -f $Email_from -t support@kolmisoft.com -u "pcapsipdump error" -s $Email_Smtp_Server:$Email_port -m "$email_output" -o tls='auto'

    else
        /usr/local/m2/sendEmail -f $Email_from -xu $Email_Login -xp $Email_Password -t support@kolmisoft.com -u "pcapsipdump error" -s $Email_Smtp_Server:$Email_port -m "$email_output" -o tls='auto'
    fi
    
fi