#!/usr/bin/env bash
# Pi-hole: A black hole for Internet advertisements
# (c) 2017 Pi-hole, LLC (https://pi-hole.net)
# Network-wide ad blocking via your own hardware.
#
# Whitelist and blacklist domains
#
# This file is copyright under the latest version of the EUPL.
# Please see LICENSE file for your rights under this license.

# Globals
basename=pihole
piholeDir=/etc/${basename}
whitelist=${piholeDir}/whitelist.txt
blacklist=${piholeDir}/blacklist.txt
readonly wildcardlist="/etc/dnsmasq.d/03-pihole-wildcard.conf"
reload=false
addmode=true
verbose=true

domList=()
domToRemoveList=()

listMain=""
listAlt=""

helpFunc() {
  if [[ "${listMain}" == "${whitelist}" ]]; then
    param="w"
    type="white"
  elif [[ "${listMain}" == "${wildcardlist}" ]]; then
    param="wild"
    type="wildcard black"
  else
    param="b"
    type="black"
  fi

    echo "Usage: pihole -${param} [options] <domain> <domain2 ...>
Example: 'pihole -${param} site.com', or 'pihole -${param} site1.com site2.com'
${type^}list one or more domains

Options:
  -d, --delmode       Remove domain(s) from the ${type}list
  -nr, --noreload     Update ${type}list without refreshing dnsmasq
  -q, --quiet         Make output less verbose
  -h, --help          Show this help dialog
  -l, --list          Display all your ${type}listed domains"

  exit 0
}

EscapeRegexp() {
  # This way we may safely insert an arbitrary
  # string in our regular expressions
  # Also remove leading "." if present
  echo $* | sed 's/^\.*//' | sed "s/[]\.|$(){}?+*^]/\\\\&/g" | sed "s/\\//\\\\\//g"
}

HandleOther() {
  # First, convert everything to lowercase
  domain=$(sed -e "y/ABCDEFGHIJKLMNOPQRSTUVWXYZ/abcdefghijklmnopqrstuvwxyz/" <<< "$1")

  # Check validity of domain
  validDomain=$(echo "${domain}" | perl -lne 'print if /(?!.*[^a-z0-9-\.].*)^((?=[a-z0-9-]{1,63}\.)(xn--)?[a-z0-9-]+\.)*[a-z]{2,63}/')
  if [[ -z "${validDomain}" ]]; then
    echo "::: $1 is not a valid argument or domain name"
  else
    domList=("${domList[@]}" ${validDomain})
  fi
}

PoplistFile() {
  # Check whitelist file exists, and if not, create it
  if [[ ! -f ${whitelist} ]]; then
    touch ${whitelist}
  fi

  for dom in "${domList[@]}"; do
      # Logic: If addmode then add to desired list and remove from the other; if delmode then remove from desired list but do not add to the other
    if ${addmode}; then
      AddDomain "${dom}" "${listMain}"
      RemoveDomain "${dom}" "${listAlt}"
      if [[ "${listMain}" == "${whitelist}" || "${listMain}" == "${blacklist}" ]]; then
        RemoveDomain "${dom}" "${wildcardlist}"
      fi
    else
      RemoveDomain "${dom}" "${listMain}"
    fi
  done
}

AddDomain() {
  list="$2"
  domain=$(EscapeRegexp "$1")

  if [[ "${list}" == "${whitelist}" || "${list}" == "${blacklist}" ]]; then
    bool=true
    # Is the domain in the list we want to add it to?
    grep -Ex -q "${domain}" "${list}" > /dev/null 2>&1 || bool=false

    if [[ "${bool}" == false ]]; then
      # Domain not found in the whitelist file, add it!
      if [[ "${verbose}" == true ]]; then
      echo "::: Adding $1 to $list..."
      fi
      reload=true
      # Add it to the list we want to add it to
      echo "$1" >> "${list}"
    else
      if [[ "${verbose}" == true ]]; then
        echo "::: ${1} already exists in ${list}, no need to add!"
      fi
    fi
  elif [[ "${list}" == "${wildcardlist}" ]]; then
    source "${piholeDir}/setupVars.conf"
    # Remove the /* from the end of the IPv4addr.
    IPV4_ADDRESS=${IPV4_ADDRESS%/*}
    IPV6_ADDRESS=${IPV6_ADDRESS}

    bool=true
    # Is the domain in the list?
    grep -e "address=\/${domain}\/" "${wildcardlist}" > /dev/null 2>&1 || bool=false

    if [[ "${bool}" == false ]]; then
      if [[ "${verbose}" == true ]]; then
      echo "::: Adding $1 to wildcard blacklist..."
      fi
      reload=true
      echo "address=/$1/${IPV4_ADDRESS}" >> "${wildcardlist}"
      if [[ "${#IPV6_ADDRESS}" > 0 ]]; then
        echo "address=/$1/${IPV6_ADDRESS}" >> "${wildcardlist}"
      fi
    else
      if [[ "${verbose}" == true ]]; then
        echo "::: ${1} already exists in wildcard blacklist, no need to add!"
      fi
    fi
  fi
}

RemoveDomain() {
    list="$2"
    domain=$(EscapeRegexp "$1")

    if [[ "${list}" == "${whitelist}" || "${list}" == "${blacklist}" ]]; then
      bool=true
      # Is it in the list? Logic follows that if its whitelisted it should not be blacklisted and vice versa
      grep -Ex -q "${domain}" "${list}" > /dev/null 2>&1 || bool=false
      if [[ "${bool}" == true ]]; then
        # Remove it from the other one
        echo "::: Removing $1 from $list..."
        # /I flag: search case-insensitive
        sed -i "/${domain}/Id" "${list}"
        reload=true
      else
        if [[ "${verbose}" == true ]]; then
          echo "::: ${1} does not exist in ${list}, no need to remove!"
        fi
      fi
    elif [[ "${list}" == "${wildcardlist}" ]]; then
      bool=true
      # Is it in the list?
      grep -e "address=\/${domain}\/" "${wildcardlist}" > /dev/null 2>&1 || bool=false
      if [[ "${bool}" == true ]]; then
        # Remove it from the other one
        echo "::: Removing $1 from $list..."
        # /I flag: search case-insensitive
        sed -i "/address=\/${domain}/Id" "${list}"
        reload=true
      else
        if [[ "${verbose}" == true ]]; then
          echo "::: ${1} does not exist in ${list}, no need to remove!"
        fi
      fi
    fi
}

Reload() {
  # Reload hosts file
  pihole -g -sd
}

Displaylist() {
  if [[ "${listMain}" == "${whitelist}" ]]; then
    string="gravity resistant domains"
  else
    string="domains caught in the sinkhole"
  fi
  verbose=false
  echo -e "Displaying $string:\n"
  count=1
  while IFS= read -r RD; do
    echo "${count}: ${RD}"
    count=$((count+1))
  done < "${listMain}"
  exit 0;
}

for var in "$@"; do
  case "${var}" in
    "-w" | "whitelist"   ) listMain="${whitelist}"; listAlt="${blacklist}";;
    "-b" | "blacklist"   ) listMain="${blacklist}"; listAlt="${whitelist}";;
    "-wild" | "wildcard" ) listMain="${wildcardlist}";;
    "-nr"| "--noreload"  ) reload=false;;
    "-d" | "--delmode"   ) addmode=false;;
    "-f" | "--force"     ) force=true;;
    "-q" | "--quiet"     ) verbose=false;;
    "-h" | "--help"      ) helpFunc;;
    "-l" | "--list"      ) Displaylist;;
    *                    ) HandleOther "${var}";;
  esac
done

shift

if [[ $# = 0 ]]; then
  helpFunc
fi

PoplistFile

if ${reload}; then
  Reload
fi