#!/bin/bash

if [ $# = 0 ]; then
    echo "Immediately whitelists one or more domains."
    echo "Usage: whitelist.sh domain1 [domain2 ...]"
fi

combopattern=""

# For each argument passed to this script
for var in "$@"
do
  echo "Whitelisting $var..."

  # Construct basic pattern to match domain name.
  basicpattern=$(echo $var | awk -F '[# \t]' 'NF>0&&$1!="" {print ""$1""}' | sed 's/\./\\./g')

  if [ "$basicpattern" != "" ]; then
    # Add to the combination pattern that will be used below
    if [ "$combopattern" != "" ]; then combopattern="$combopattern|"; fi
    combopattern="$combopattern$basicpattern"

    # Also add the domain to the whitelist but only if it's not already present
    grep -E -q "^$basicpattern$" /etc/pihole/whitelist.txt \
    || echo "$var" >> /etc/pihole/whitelist.txt
  fi
done

# Now report on and remove matched domains
if [ "$combopattern" != "" ]; then
  echo "Modifying hosts file..."
  
  # Construct pattern to match entry in hosts file.
  # This consists of one or more IP addresses followed by the domain name.
  pattern=$(echo $combopattern | awk -F '[# \t]' '{printf "%s", "^(([0-9]+\.){3}[0-9]+ +)+("$1")$"}')

  # Output what will be removed and then actually remove
  sed -r -n 's/'"$pattern"'/  Removed: \3/p' /etc/pihole/gravity.list
  sed -r -i '/'"$pattern"'/d' /etc/pihole/gravity.list

  echo "** $# domain(s) whitelisted."
  # Force dnsmasq to reload /etc/pihole/gravity.list
  kill -HUP $(pidof dnsmasq)
fi