#!/bin/bash

# This script will echo the IPv4 of this unix machine. E.g. 100.200.300.45
# If passed -format-for-tomcat-context, it will echo the same with a pipe
# symbol up front and all the . escaped with a "\". E.g. "|100\.200\.300\.45"

#http://www.wikihow.com/Find-Your-IP-Address-on-a-Mac#Finding_Your_Internal_IP_Using_the_Terminal_sub
#http://stackoverflow.com/questions/1469849/how-to-split-one-string-into-multiple-strings-in-bash-shell
#http://www.linuxforums.org/forum/red-hat-fedora-linux/193076-ifconfig-doesnt-display-ipv4-address.html


# The following echoes the IPv4, e.g. 100.200.300.45
# But need to still replace the . with \.

#echo `ifconfig eth0 | grep "inet " | grep -v 127.0.0.1`|cut -d' ' -f 2|cut -d':' -f 2

tmp=`ifconfig eth0 2>&1 | grep "inet " | grep -v 127.0.0.1`
# As below: if $tmp is empty, can just return |, as that doesn't really matter. Will be consistent with windows
if [[ $tmp = *"Device not found"* ]] || [[ -z "${tmp// }" ]]; then
    # eth0 is not found on Kathy's machine where the default ethernet device has a different name
    # But ifconfig on its own works there, so try that next
    tmp=`ifconfig 2>&1 | grep "inet " | grep -v 127.0.0.1`
    if [[ $tmp = *"Device not found"* ]] || [[ -z "${tmp// }" ]]; then
	echo "|"
    fi
fi

# grab just the portion of the line we want
tmp=`echo $tmp|cut -d' ' -f 2|cut -d':' -f 2`

# if requested to format the IPv4 for the solr.xml tomcat context file
if [ "$1" == "-format-for-tomcat-context" ]; then

    #http://stackoverflow.com/questions/13210880/replace-one-substring-for-another-string-in-shell-script
    #${original_string//searchterm/$string_to_replace_searchterm_with}
    replace="."
    replacement="\."
    
    tmp=${tmp//$replace/$replacement}
    
    # next, if the tmp variable is not the empty string, prefix the | operator
    # http://unix.stackexchange.com/questions/146942/how-can-i-test-if-a-variable-is-empty-or-contains-only-spaces
    # Can just return | if $tmp is empty, as that doesn't really matter. Will be consistent with windows
    if [[ ! -z "${tmp// }" ]]; then
	tmp="|$tmp"
    else
	tmp="|"
    fi

fi

echo $tmp