push

#!/usr/bin/env bash

################################################################################
# Global variables.
################################################################################

_NAME="$(command basename "$0")"
_HELP_DOC="Send a push notification using Pushover, a push notification service.

Usage:
  $_NAME [options] <text_message>

Options:
  -p    Send message with high priority.
  -h    Print help.

Environment variables:
  PUSHOVER_USER		https://pushover.net
  PUSHOVER_TOKEN	https://pushover.net/apps/build"
CURL_ARGS="--connect-timeout 2 --max-time 5"

################################################################################
# Helper methods.
################################################################################

# Usage:
#       error <message> [<exit_code>]
error() {
	[[ $2 -eq 0 ]] && std_err_or_out=1 || std_err_or_out=2
	builtin echo "$_NAME: $1" >&"$std_err_or_out"
	exit "${2:-1}"
}

################################################################################
# Validate input.
################################################################################

priority=0
while getopts ":ph" arg; do
	case $arg in
	p) # priority
		priority=1
		;;
	h) # help
		builtin echo "$_HELP_DOC" && exit
		;;
	*)
		builtin echo "$_HELP_DOC" >&2 && exit 64 # EX_USAGE
		;;
	esac
done
shift $((OPTIND - 1))
[[ "${!#}" == "-p" ]] && priority=1 && set -- "${@:1:$#-1}"

[[ -z "$PUSHOVER_USER" ]] && error "missing environment variable, please set PUSHOVER_USER" 78   # EX_CONFIG
[[ -z "$PUSHOVER_TOKEN" ]] && error "missing environment variable, please set PUSHOVER_TOKEN" 78 # EX_CONFIG
[[ $# -eq 0 ]] && error "missing input, please pass a message" 64                                # EX_USAGE

################################################################################
# Execute.
################################################################################

# shellcheck disable=SC2086
response="$(
	command curl -qsS $CURL_ARGS \
		--form-string "user=$PUSHOVER_USER" \
		--form-string "token=$PUSHOVER_TOKEN" \
		--form-string "priority=$priority" \
		--form-string "message=$*" \
		"https://api.pushover.net/1/messages.json"
)" || error "unable to reach pushover.net"
if command grep -q '"user":"invalid"' <<<"$response"; then
	error "invalid user, please check the environment variable PUSHOVER_USER" 78 # EX_CONFIG
elif command grep -q '"token":"invalid"' <<<"$response"; then
	error "invalid token, please check the environment variable PUSHOVER_TOKEN" 78 # EX_CONFIG
elif ! command grep -q '"status":1' <<<"$response"; then
	error "unknown error: $response"
fi