#!/bin/bash

# Check if an interface name is provided
if [ -z "$1" ]; then
    echo "Usage: $0 <network-interface>"
    exit 1
fi

INTERFACE=$1

# Get the IP subnet for the provided network interface
IP_SUBNET=$(ip route show dev "$INTERFACE" | grep -v default | awk '{print $1}')


# Check if the IP information was found
if [ -z "$IP_SUBNET" ]; then
    echo "No IP address found for interface $INTERFACE."
    exit 1
fi

# Scan the subnet using nmap, running as root
echo "Scanning the subnet $IP_SUBNET..."
OUTPUT=$(sudo nmap -sP "$IP_SUBNET")

# Parse the nmap output and present it in a table
#echo "$OUTPUT" | awk '/Nmap scan report for/{
#    if ($5 ~ /^\(/) { ip=$5; name="Unknown"; }
#    else if ($6 ~ /^\(/) { name=$5; ip=$6; }
#    else { name="Unknown"; ip=$5; }
#
#    ip=gensub(/\(|\)/, "", "g", ip);  # Remove parentheses from IP
#
#    getline; getline; mac=$3; brand="";
#
#    # Capture the entire remainder as brand, remove parentheses
#    for (i=4; i<=NF; i++) brand = brand $i " ";
#    brand=gensub(/^\(|\)$/, "", "g", brand);  # Clean brand formatting
#    print name, ip, mac, brand
#}' | column -t -s ' ' -o ' | ' | awk 'BEGIN {print "Name               | IP Address       | MAC Address        | Brand\n-----------------------------------------------------------------"} {print}'

# Parse the nmap output and present it in a table
echo "$OUTPUT" | awk '/Nmap scan report for/{
    if ($5 ~ /^\(/) { ip=$5; name="Unknown"; }
    else if ($6 ~ /^\(/) { name=$5; ip=$6; }
    else { name="Unknown"; ip=$5; }

    ip=gensub(/\(|\)/, "", "g", ip);  # Remove parentheses from IP

    getline; getline; mac=$3; brand=$4;  # Skip status line and move to MAC and Brand
    gsub(/\(|\)/, "", brand);  # Clean brand formatting
    print name, ip, mac, brand
}' | column -t -s ' ' -o ' | ' | awk 'BEGIN {print "Name               | IP Address | MAC Address       | Brand\n-----------------------------------------------------------------"} {print}'


## Parse the nmap output and present it in a table
#echo "$OUTPUT" | awk '/Nmap scan report for/{
#    if ($5 ~ /^\(/) { ip=$5; name="Unknown"; }
#    else if ($6 ~ /^\(/) { name=$5; ip=$6; }
#    else { name="Unknown"; ip=$5; }
#
#    ip=gensub(/\(|\)/, "", "g", ip);  # Remove parentheses from IP
#
#    getline; getline; mac=$3; brand="";
#
#    # Capture the entire remainder as brand
#    if ($(NF-1) ~ /^\(/) {  # Check if the second last field starts with (
#        for (i=4; i<=NF; i++) brand = brand $i " ";
#        sub(/\s+$/, "", brand);  # Trim trailing space
#        brand=gensub(/\((.*)\)/, "\\1", "g", brand);  # Remove outer parentheses
#    }
#    print name, ip, mac, brand
#}' | column -t -s ' ' -o ' | ' | awk 'BEGIN {print "Name               | IP Address       | MAC Address        | Brand\n--------------------------------------------------------------------------------"} {print}'