#!/usr/bin/env bash

SCRIPT_PATH=$(realpath -s "${0}")
SCRIPT_DIR=$(dirname "$SCRIPT_PATH")
SCRIPT=$(basename "$SCRIPT_PATH")

usage() {
  cat <<EOF
Usage: $SCRIPT [OPTIONS]... ZONE[@VIEW]

Add new DNS zones.

Options:
  -c, --config           path to config file
  -h, --help             print this help message
  -f, --force            add zone without confirmation prompt
  -i, --interactive      interactively ask for missing arguments
  -t, --config-template  config file/template (overrides value set in ZONE_TEMPLATES config option)
  -z, --zone-template    zone file/template (overrides value set in ZONE_TEMPLATES config option)
EOF
  exit
}

config_file="/etc/dns-manager/config.sh"
config_template=""
force=false
interactive=false
zone=""
zone_template=""

declare -a args=()
while [ -n "$1" ]; do
  opt=$1
  shift
  case "$opt" in
    -c|--config)
      config_file=$1
      if ! shift; then
        echo "$SCRIPT: missing argument to option -- '$opt'" >&2
	exit 1
      fi
    ;;
    -h|--help)
      usage
    ;;
    -f|--force)
      force=true
    ;;
    -i|--interactive)
      interactive=true
    ;;
    -t|--config-template)
      config_template=$1
      if ! shift; then
        echo "$SCRIPT: missing argument to option -- '$opt'" >&2
	exit 1
      fi
    ;;
    -z|--zone-template)
      zone_template=$1
      if ! shift; then
        echo "$SCRIPT: missing argument to option -- '$opt'" >&2
	exit 1
      fi
    ;;
    -*)
      echo "$SCRIPT: invalid option -- '$opt'" >&2
      exit 1
    ;;
    *)
      args+=("$opt")
      if (( ${#args[@]} > 1 )); then
        echo "$SCRIPT: invalid argument -- '$opt'" >&2
        exit 1
      fi
    ;;
  esac
done

source "$config_file" || exit 2

LIB_DIR=${LIB_DIR:-$SCRIPT_DIR/lib}
source "$LIB_DIR"/dns.sh || exit 3
source "$LIB_DIR"/output.sh || exit 3

set -- "${args[@]}"

zone=$1
if shift; then
  dns_check_zone_name_view "$zone" zone view || exit 10
elif $interactive; then
  dns_read_zone_view zone view || exit 11
else
  echo "$SCRIPT: missing argument -- ZONE[@VIEW]" >&2
  exit 1
fi

declare -A output
if [ "${view}" == "*" ]; then
  json_array_to_bash views < <(dns_zone_views)
else
  views=("$view")
fi

for view in "${views[@]}"; do
  dns_get_base_config "$view" zone_dir conf_dir || exit 13

  zone_conf_file="$conf_dir/$zone.conf"
  [ -f "$zone_conf_file" ] && echo "ERROR: config file already exists -- '$zone_conf_file'" >&2 && exit 14

  zone_file="$zone_dir/$zone.zone"
  [ -f "$zone_file" ] && echo "ERROR: zone file already exists -- '$zone_file'" >&2 && exit 15

  IFS=":" read -r cfg_zone_template cfg_config_template <<<"${ZONE_TEMPLATES["$view"]}"

  conf_template=${config_template:-${cfg_config_template}}
  [ -z "$conf_template" ] && echo "ERROR: config template not configured nor specified by '-t' option" >&2 && exit 16
  ! [ -f "$conf_template" ] && echo "ERROR: zone config template: no such file -- '$conf_template'" >&2 && exit 17

  zone_template=${zone_template:-${cfg_zone_template}}
  [ -z "$zone_template" ] && echo "ERROR: zone template not configured nor specified by '-z' option" >&2 && exit 18
  ! [ -f "$zone_template" ] && echo "ERROR: zone template: no such file -- '$zone_template'" >&2 && exit 19

  dns_check_zone_view "$zone@$view" &>/dev/null && echo "ERROR: non-managed zone already exists in DNS -- '$zone@$view'" >&2 && exit 16
done

if ! $force; then
  for view in "${views[@]}"; do
    echo "View: $view"
    echo -e "\e[32m+ $TAB$zone\e[0m"
  done
  echo
  ! yes_no "Proceed?" && echo -e "Aborted" && exit
  echo
fi

echo -n "Adding zone to config... "
for view in "${views[@]}"; do
  dns_get_base_config "$view" zone_dir conf_dir conf_file || exit 13

  zone_conf_file="$conf_dir/$zone.conf"
  zone_file="$zone_dir/$zone.zone"

  IFS=":" read -r cfg_zone_template cfg_config_template <<<"${ZONE_TEMPLATES["$view"]}"
  conf_template=${config_template:-${cfg_config_template}}
  zone_template=${zone_template:-${cfg_zone_template}}

  ! sed "s#%ZONE%#$zone#g;s#%ZONE_FILE%#$zone_file#g" "$conf_template" >"$zone_conf_file" && echo "ERROR: unable to write to config file -- '$zone_conf_file'" >&2 && exit 20
  ! sed "s#%ZONE%#$zone#g" "$zone_template" >"$zone_file" && echo "ERROR: unable to write to zone file -- '$zone_file'" >&2 && exit 21
  ! chown named:named "$zone_file" && echo "ERROR: unable to set ownership of zone file to 'named:named' -- '$zone_file'" >&2 && exit 22

  tmp=$(mktemp)
  cat >"$tmp" <<EOF
/*
 * This file was generated by DNS-Manager.
 * DO NOT EDIT, YOUR CHANGES WILL BE OVERWRITTEN!
 */
EOF
  while IFS=$NEWLINE read -r file; do
    if ! cat "$file" >>"$tmp"; then
      echo "ERROR: unable to write to temp file -- '$tmp'" >&2
      rm "$tmp"
      exit 23
    fi
  done < <(find "$conf_dir" -maxdepth 1 -type f -name '*.conf')
  if ! cat "$tmp" > "$conf_file"; then
    echo "ERROR: unable to write config file -- '$conf_file'" >&2
    rm "$tmp"
    exit 24
  fi
  rm "$tmp"
done
echo "Ok"

dns_reload_config || exit 25