#!/bin/bash 

str_dir_name=`dirname $0`
. $str_dir_name/xcatlib.sh

if [ -z "$1" ];then
    echo "$0 need the interface name."
    exit
fi

str_nic_name=$1
str_ip_mask=`ip addr show dev $str_nic_name | grep inet | grep -v inet6 | awk '{print $2}' | head -n 1`

str_ip=`echo $str_ip_mask | awk -F'/' '{print $1}'`
str_mask=`echo $str_ip_mask | awk -F'/' '{print $2}'`

str_net=$(v4calcnet $str_ip $str_mask)

num_i=1
while [ $num_i -le $NETWORKS_LINES ];do
    eval str_temp=\$NETWORKS_LINE$num_i
    str_net_table=`echo $str_temp | awk -F'net=' '{print $2}' | awk -F'|' '{print $1}'`

    if [ "$str_net" = "$str_net_table" ];then
        str_gateway=`echo $str_temp | awk -F'gateway=' '{print $2}' | awk -F'|' '{print $1}' | sed 's:^/::'`
    fi
    num_i=$((num_i+1))
done

if [ -z "$str_gateway" ];then
    echo "Can not find the corresponding network defination"
    exit
fi

echo $str_gateway |  grep -E '^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$' > /dev/null
if [ $? -ne 0 ];then
    echo "The gateway must be ipv4 address: $str_gateway"
    exit
fi

#change the default route
route del default
route add default gw $str_gateway dev $str_nic_name

#change the gateway persistent
if [ -f "/etc/debian_version" ];then
    debianpreconf
    #delete the gateway from all configuration files
    sed -i "s/.*gateway.*//" /etc/network/interfaces.d/*
    
    str_conf_file="/etc/network/interfaces.d/$str_nic_name"
    echo "  gateway $str_gateway --" >> $str_conf_file
elif [ -f "/etc/SuSE-release" ];then
    grep -i "default" /etc/sysconfig/network/routes
    if [ $? -eq 0 ];then
        sed -i "s/.*default.*/default ${str_gateway} - -/i" /etc/sysconfig/network/routes
    else
        echo "default ${str_gateway} - -" >> /etc/sysconfig/network/routes
    fi
else
    grep -i "GATEWAY" /etc/sysconfig/network
    if [ $? -eq 0 ];then
        sed -i "s/.*GATEWAY.*/GATEWAY=${str_gateway}/i" /etc/sysconfig/network
    else
        echo "GATEWAY=${str_gateway}" >> /etc/sysconfig/network
    fi
fi