#!/bin/bash
# ---------------------------------------------------
#  Send notification to a telegram account thru a bot account
#  Configuration is stored in /etc/telegram-notify.conf
#  Depends on curl 
#
#  Revision history :
#    10/01/2016, v1.0 - Creation by N. Bernaerts
#    22/01/2016, v1.1 - Handle emoticons
#    06/08/2016, v1.2 - Add API key and User ID parameters
#                       Remove dependency to PERL
#    08/08/2016, v1.3 - Add --document, --html and --silent options
#    10/11/2016, v1.4 - Add --icon option
#    11/01/2018, v1.5 - Add possibility of piped text, idea from Yasir Atabani
#    19/05/2018, v1.6 - Add socks5 proxy option, idea from RangerRU
#    28/06/2018, v1.7 - Add --warning and --config options, idea from Markus Hof
#    08/08/2019, v1.8 - Add --file option (file holding text to display)
#    23/09/2019, v1.9 - Add --quiet option, thanks to Alberto Panu
#    06/02/2020, v2.0 - Add --disable_preview option, thanks to Alex P.
#    30/01/2022, v2.1 - Add --code option and --protect
#    03/05/2022, v2.2 - Bug fixes, thanks to Radius17
#    31/01/2023, v2.3 - Fix for image and document sending, thanks to jacklul
#    01/02/2023, v2.4 - Add --debug and --position option, idea from z3r0l1nk
#    03/02/2023, v2.5 - Add --audio option and code rewrite
# ---------------------------------------------------

# initialise variables
TEXT=""
ICON=""
TYPE="text"
MODE="markdown"
DISABLE_PREVIEW="false"
PROTECT="false"
SILENT="false"
QUIET="false"
LINE_BREAK=$'\n'

# Configuration file
FILE_CONF="/etc/telegram-notify.conf"

# -------------------------------------------------------
#   Check tools availability
# -------------------------------------------------------

command -v curl >/dev/null 2>&1 || { echo "[Error] Please install curl"; exit 1; }

# -------------------------------------------------------
#   Loop to load arguments
# -------------------------------------------------------

# if no argument, display help
if [ $# -eq 0 ] 
then
  echo "Tool to send a message to a Telegram User or Channel."
  echo "Message is sent from a Telegram Bot and can contain icon, text, image and/or document."
  echo "Main parameters are :"
  echo "  --text <text>          Text of the message (use - for piped text)"
  echo "  --file <file>          File holding the text of the message"
  echo "  --photo <file>         Image to display"
  echo "  --document <file>      Document to transfer"
  echo "  --position <lat,long>  GPS position"
  echo "  --audio <file>         Audio file (converted to opus if needed)"
  echo "Options are :"
  echo "  --title <title>     Title of the message (if text message)"
  echo "  --html              Use HTML mode for text content (markdown by default)"
  echo "  --disable_preview   Don't create previews for links, image and/or document"
  echo "  --protect           Protects the contents of the sent message from forwarding and saving"
  echo "  --silent            Send message in silent mode (no user notification on the client)"
  echo "  --quiet             Don't print message to stdout"
  echo "  --config <file>     use alternate config file, instead of default ${FILE_CONF}"
  echo "  --user <user-id>    Recipient User or Channel ID (replaces user-id= in ${FILE_CONF})"
  echo "  --key <api-key>     API Key of your Telegram bot (replaces api-key= in ${FILE_CONF})"
  echo "Optional icons are :"
  echo "  --success           Add a success icon"
  echo "  --warning           Add a warning icon"
  echo "  --error             Add an error icon"
  echo "  --question          Add a question mark icon"
  echo "  --icon <code>       Add an icon by UTF code (ex 1F355)"
  echo "Other options are :"
  echo "  --debug             Display JSON answer for debug"
  echo "Here is an example of piped text :"
  echo "  echo 'text to be displayed' | telegram-notify --success --text -"
  exit
fi

# loop to retrieve arguments
while test $# -gt 0
do
  case "$1" in
    "--text") shift; TEXT="$1"; shift; ;;
    "--file") shift; FILE="$1"; shift; ;;
    "--photo") shift; TYPE="pict"; FILE="$1"; shift; ;;
    "--document") shift; TYPE="doc"; FILE="$1"; shift; ;;
    "--audio") shift; TYPE="audio"; FILE="$1"; shift; ;;
    "--position") shift; TYPE="pos"; POSITION="$1"; shift; ;;
    "--title") shift; TITLE="$1"; shift; ;;
    "--html") MODE="html"; shift; ;;
    "--disable_preview") DISABLE_PREVIEW="true"; shift; ;;
    "--protect") PROTECT="true"; shift; ;;
    "--silent") SILENT="true"; shift; ;;
    "--quiet") QUIET="true"; shift; ;;
    "--config") shift; FILE_CONF="$1"; shift; ;;
    "--user") shift; USER_ID="$1"; shift; ;;
    "--key") shift; API_KEY="$1"; shift; ;;
    "--success") ICON=$(echo -e "\U2705"); shift; ;;
    "--warning") ICON=$(echo -e "\U26A0"); shift; ;;
    "--error") ICON=$(echo -e "\U1F6A8"); shift; ;;
    "--question") ICON=$(echo -e "\U2753"); shift; ;;
    "--icon") shift; ICON=$(echo -e "\U$1"); shift; ;;
    "--debug") DEBUG="ok"; shift; ;;
    *) shift; ;;
  esac
done

# -------------------------------------------------------
#   Read configuration
# -------------------------------------------------------

# if configuration file is present
if [ -f "${FILE_CONF}" ]
then
	# display used config file unless --quiet parameter is used
	[ "${QUIET}" = "false" ] && echo "[Info] Using configuration file ${FILE_CONF}"

	# if needed, load from configuration file
	[ "${API_KEY}" = "" ] && API_KEY=$(cat "${FILE_CONF}" | grep "api-key=" | cut -d'=' -f2)
	[ "${USER_ID}" = "" ] && USER_ID=$(cat "${FILE_CONF}" | grep "user-id=" | cut -d'=' -f2)

	# load socks proxy from configuration file
	SOCKS_PROXY=$(cat "${FILE_CONF}" | grep "socks-proxy=" | cut -d'=' -f2)
else
	# display warning unless --quiet parameter is used
	[ "${QUIET}" = "false" ] && echo "[Warning] Configuration file missing ${FILE_CONF}"
fi

# check API key and User ID
[ "${API_KEY}" = "" ] && { echo "[Error] Please provide API key or set it in ${FILE_CONF}"; exit 1; }
[ "${USER_ID}" = "" ] && { echo "[Error] Please provide User ID or set it in ${FILE_CONF}"; exit 1; }

# Check for file existence
[ "${FILE}" != "" -a ! -f "${FILE}" ] && { echo "[error] File ${FILE} doesn't exist"; exit 1; }

# generate temporary directory
TMP_DIR=$(mktemp -t -d "telegram-XXXXXXXX")
TMP_AUDIO="${TMP_DIR}/audio.ogg"

# -------------------------------------------------------
#   Text : space, line break, title and icon
# -------------------------------------------------------

# if text is a file, get its content
[ "${TYPE}" = "text" -a "${FILE}" != "" ] && TEXT=$(cat "${FILE}")

# if text is to be read from pipe, get it
[ ! -t 0 -a "${TEXT}" = "-" ] && TEXT=$(cat)

# convert \n to LF
TEXT=$(echo "${TEXT}" | sed 's:\\n:\n:g')

# if title defined, add it with line break
[ "${TITLE}" != "" -a "${MODE}" = "html" ] && TEXT="<b>${TITLE}</b>${LINE_BREAK}${LINE_BREAK}${TEXT}"
[ "${TITLE}" != "" -a "${MODE}" = "markdown" ] && TEXT="*${TITLE}*${LINE_BREAK}${LINE_BREAK}${TEXT}"

# if icon defined, include ahead of notification
[ "${ICON}" != "" ] && TEXT="${ICON} ${TEXT}"

# -----------------
#   Notification
# -----------------

# default option
ARR_OPTIONS=( "--silent" "--insecure" )

# if needed, socks5 option
[ "${SOCKS_PROXY}" != "" ] && ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--socks5-hostname" "${SOCKS_PROXY}" )

case "${TYPE}" in

  # text
  "text") 
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--data" "chat_id=${USER_ID}" "--data" "disable_notification=${SILENT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--data" "protect_content=${PROTECT}" "--data" "disable_web_page_preview=${DISABLE_PREVIEW}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--data" "parse_mode=${MODE}" "--data" "text=${TEXT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "https://api.telegram.org/bot${API_KEY}/sendMessage" )
    ;;
    
  # image
  "pict")
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "chat_id=${USER_ID}" "--form" "disable_notification=${SILENT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "protect_content=${PROTECT}" "--form" "disable_web_page_preview=${DISABLE_PREVIEW}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "parse_mode=${MODE}" "--form" "photo=@${FILE}" "--form" "caption=${TEXT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "https://api.telegram.org/bot${API_KEY}/sendPhoto" )
    ;;

  # document
  "doc") 
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "chat_id=${USER_ID}" "--form" "disable_notification=${SILENT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "protect_content=${PROTECT}" "--form" "disable_web_page_preview=${DISABLE_PREVIEW}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "parse_mode=${MODE}" "--form" "document=@${FILE}" "--form" "caption=${TEXT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "https://api.telegram.org/bot${API_KEY}/sendDocument" )
    ;;

  # position
  "pos") 
    # extract coordonates
    LATITUDE=$(echo "${POSITION}" | cut -d',' -f1)
    LONGITUDE=$(echo "${POSITION}" | cut -d',' -f2)

    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "chat_id=${USER_ID}" "--form" "disable_notification=${SILENT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "parse_mode=${MODE}" "--form" "caption=${TEXT}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "latitude=${LATITUDE}" "--form" "longitude=${LONGITUDE}" )
    ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "https://api.telegram.org/bot${API_KEY}/sendLocation" )
    ;;

  # audio
  "audio") 
    # if needed, convert audio file
    IS_OPUS=$(file "${FILE}" | grep "Opus audio")
    command -v ffmpeg >/dev/null 2>&1 && IS_FFMPEG="ok"

    [ "${IS_OPUS}" != "" ] && TMP_AUDIO="${FILE}"
    [ "${IS_OPUS}" = "" -a "${IS_FFMPEG}" = "ok" ] && ffmpeg -i "${FILE}" -loglevel quiet -c libopus -ab 64k "${TMP_AUDIO}"

    # if proper audio file
    if [ -f "${TMP_AUDIO}" ]
    then
      ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "chat_id=${USER_ID}" "--form" "disable_notification=${SILENT}" )
      ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "--form" "parse_mode=${MODE}" "--form" "voice=@${TMP_AUDIO}" "--form" "caption=${TEXT}" )
      ARR_OPTIONS=( "${ARR_OPTIONS[@]}" "https://api.telegram.org/bot${API_KEY}/sendVoice" )
    else
      ARR_OPTIONS=( )
      [ "${QUIET}" = "false" ] && echo "[Error] FFmpeg absent, Opus conversion impossible"
    fi
    ;;

  *) 
    ARR_OPTIONS=( )
    ;;
esac

# if there is a message to send
if [ ${#ARR_OPTIONS[@]} -gt 0 ]
then
  # send message
  RESULT=$(curl "${ARR_OPTIONS[@]}")

  # if debug mode, display bot answer
  if [ "${DEBUG}" = "ok" ]
  then
    echo "option : ${ARR_OPTIONS[@]}"
    echo "answer : ${RESULT}" 
  fi

#  else, nothing, error
else
  # display error message unless --quiet parameter is used
  [ "${QUIET}" = "false" ] && echo "[Error] Nothing to notify"
  
fi

# remove temporary directory
rm -r "${TMP_DIR}"