#!/usr/bin/env bash

# usage
usage() {
USAGE=$(cat <<EOF
Usage: notifier <subject> <content> [<mail address>]

Sends out notifications. Please see man notifier.
EOF
)
	echo "$USAGE";
}

set -e;

NOTIFIER_SUBJECT=$1
if [ -z "$NOTIFIER_SUBJECT" ]; then
	echo "No subject given";
	echo "";
	usage;
	exit 1;
fi

NOTIFIER_CONTENT=$2
if [ -z "$NOTIFIER_CONTENT" ]; then
	echo "No content given";
	echo "";
	usage;
	exit 1;
fi

argsMailProvided="false"

if [[ -n "$3" ]]; then
  argsMailProvided="true"
fi

# check for config file
apply_config() {
  local config=$1;

  if [[ ! -f "$config" ]]; then
      echo "No config file specified";
      echo "";
      usage;
      exit 1;
  fi

  set -a;
  # shellcheck disable=SC1090
  source "$config";
  set +a;
}

check_requirements() {
	local mailEnabled=$1;
	local gotifyEnabled=$2;
  local mailAddress=$3;

  if [[ "${mailEnabled}" == "false" && "${gotifyEnabled}" == "false" ]]; then
    echo "Mail and gotify cannot be disabled simultanously";
    echo "";
    usage;
    exit 1;
  fi

	if [[ "${mailEnabled}" == "true" ]]; then
    type mailx &> /dev/null || { echo "Requiring 'mailx' but it's not installed"; exit 1; }

    if [ -z "${mailAddress}" ]; then
      echo "No mail address given";
      echo "";
      usage;
      exit 1;
    fi
	fi

	if [[ "${gotifyEnabled}" == "true" ]]; then
    type gotify &> /dev/null || { echo "Requiring 'gotify' but it's not installed"; exit 1; }
	fi
}

source_config() {
  local configFallback=$1;
  local configGlobalFallback=$2;

  checkMailEnabled=${NOTIFIER_MAIL_ENABLED:-1}
  checkGotifyEnabled=${NOTIFIER_GOTIFY_ENABLED:-1}
  checkMailAddress=${NOTIFIER_MAIL_ADDRESS:-1}

  if [[ ! -v "$checkMailEnabled" && ! -v "$checkGotifyEnabled" && ! -v "$checkMailAddress" ]]; then
    echo "Using environment variables for configuration instead of configuration files";
    return;
  else
    echo "Using configuration files";
  fi

  if [[ -f "$configFallback" ]]; then
    apply_config "$configFallback";
    return;
  fi

  if [[ -f "$configGlobalFallback" ]]; then
    apply_config "$configGlobalFallback";
    return;
  fi
}
source_config "$HOME/.notifier.conf" "/etc/notifier.conf"
check_requirements "${NOTIFIER_MAIL_ENABLED}" "${NOTIFIER_GOTIFY_ENABLED}" "${NOTIFIER_MAIL_ADDRESS}"

if [[ "${argsMailProvided}" == "true" ]]; then
  NOTIFIER_MAIL_ADDRESS=$3
  echo "Overwriting mail with argument value"
fi

echo "Using NOTIFIER_MAIL_ENABLED=${NOTIFIER_MAIL_ENABLED}"
echo "Using NOTIFIER_GOTIFY_ENABLED=${NOTIFIER_GOTIFY_ENABLED}"
echo "Using NOTIFIER_MAIL_ADDRESS=${NOTIFIER_MAIL_ADDRESS}"

SUBJECT="${NOTIFIER_SUBJECT}"
MESSAGE="${NOTIFIER_CONTENT}"

if [[ "${NOTIFIER_MAIL_ENABLED}" == "true" ]]; then
  echo "$MESSAGE"|mailx -Ssendwait -s "$SUBJECT" "$NOTIFIER_MAIL_ADDRESS";
  echo "Sent notifiction via mail to $NOTIFIER_MAIL_ADDRESS"
else
  echo "Sending notifictions via mail is disabled"
fi

if [[ "${NOTIFIER_GOTIFY_ENABLED}" == "true" ]]; then

  if [[ ! -f "${HOME}/.config/gotify/cli.json" && ! -f "${HOME}/gotify/cli.json" && ! -f "./cli.json" && ! -f "/etc/gotify/cli.json" ]]; then
    echo "Cannot find a valid cli.json, please run 'gotify init' before using this"
    exit 1;
  fi

  echo "$MESSAGE"|gotify push --quiet --title "${SUBJECT}";
  echo "Sent message via gotify"
else
  echo "Sending notifictions via gotify is disabled"
fi