#!/bin/bash
TELEGRAM_TOKEN=""
PARSE_MODE="MarkdownV2"
ESCAPE_ALL=false
API_URL="https://api.telegram.org"

# _escape_text(input_text)
function _escape() {
	sed -E 's/[`~!@#$%^&*():<>.,?\|{}=+_-]/\\&/g' <<< "$1"
}

# _unescape_text(input_text)
function _unescape_text() {
	sed -E 's/\\/&�Meow�/g;s/\\�Meow�\\�Meow�\\�Meow�/\\/;s/\\�Meow�//g' <<< "$1"
}

# tg_send(chat, text, file, type, [id])
function tg_send() {
	if [[ $ESCAPE_ALL == true ]]; then
		text="$(_escape "$2")"
		echo "$2"
		echo "$text"
	else
		text="$2"
	fi
	if [[ $3 != '' ]]; then
		local type_snake=$4
		[[ $4 == '' ]] && local type_snake='document'
		[[ $4 == '' || $4 == 'document' ]] && local type="Document"
		[[ $4 == 'photo' ]] && local type="Photo"
		[[ $4 == 'audio' ]] && local type="Audio"
		[[ $4 == 'video' ]] && local type="Video"
		[[ $4 == 'animation' ]] && local type="Animation"
		[[ $4 == 'voice' ]] && local type="Voice"
		[[ $4 == 'video_note' ]] && local type="VideoNote"
		[[ $4 == 'sticker' ]] && local type="Sticker"

		if [[ $3 == "remoteFileId" ]]; then
			curl -s \
				 --form-string chat_id=$1 \
				 --form-string caption="$text" \
				 -F parse_mode=$PARSE_MODE \
				 -F $type_snake=$5 \
			 	 "${API_URL}/bot${TELEGRAM_TOKEN}/send${type}"
		else
			curl -s \
				 --form-string chat_id=$1 \
				 --form-string caption="$text" \
				 -F parse_mode=$PARSE_MODE \
			 	 -F $type_snake=@$3 \
			 	 "${API_URL}/bot${TELEGRAM_TOKEN}/send${type}"
		fi
	else
		curl -s \
			 --form-string chat_id=$1 \
			 --form-string text="$text" \
			 -F parse_mode=$PARSE_MODE \
			 "${API_URL}/bot${TELEGRAM_TOKEN}/sendMessage"
	fi
}

# tg_get_me()
function tg_get_me() {
	curl -s "${API_URL}/bot${TELEGRAM_TOKEN}/getMe"
}

# tg_get_file(id)
function tg_get_file() {
	curl -s "${API_URL}/file/bot${TELEGRAM_TOKEN}/$(curl -s "${API_URL}/bot${TELEGRAM_TOKEN}/getFile?file_id=$1" | jq -r '.result.file_path')"
}

# tg_get_messages(offset, timeout)
function _tg_get_updates() {
	curl -s "${API_URL}/bot${TELEGRAM_TOKEN}/getUpdates?offset=$1&timeout=p" | jq -c '.result[]'
}

function _on_msg() {	
	echo "[msg] ${event[from_username]}: ${event[text]}"
}

function _on_edit() {
	echo "[edit] ${event[json]}"
}

function _on_animation() {
	echo "[animation] ${event[json]}"
}

function _on_audio() {
	echo "[audio] ${event[json]}"
}

function _on_document() {
	echo "[document] ${event[json]}"
}

function _on_photo() {
	echo "[photo] ${event[json]}"
}

function _on_sticker() {
	echo "[sticker] ${event[json]}"
}

function _on_video() {
	echo "[video] ${event[json]}"
}

function _on_video_note() {
	echo "[video_note] ${event[json]}"
}

function _on_voice() {
	echo "[voice] ${event[json]}"
}

#jq_to_array(jq_expression)
function _jq_to_array() {
	declare -ga "_tmp=($(jq -r "$1" | sed 's/[][`~!@#$%^&*():;<>.,?\|{}=+-]/\\&/g;'"s@\\\'@\\'@g" ))"
}

function tg_start() {
	_offset=0
	while true; do
		IFS=$'\n'
		_events=($(_tg_get_updates $_offset 10))
		unset IFS

		for (( i=0; i<${#_events[@]}; i++ )); do
			declare -A event
			_msg_type="$(jq -r '(select(.message) | if .message.forward_date then "forwarded_message" else "message" end ), (select(.edited_message) | "edited_message")' <<< "${_events[$i]}")"

			_event_type="$(jq -r '(select(.message) | .message), (select(.edited_message) | .edited_message) | (
				(select(.animation) | "animation"),
				(select(.audio) | "audio"),
				(select(.animation == null) | select(.document) | "document"),
				(select(.photo) | "photo"),
				(select(.sticker) | "sticker"),
				(select(.video) | "video"),
				(select(.video_note) | "video_note"),
				(select(.voice) | "voice"))' <<< "${_events[$i]}")"

			_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) |
				[.message_id,
				.from.id,
				.from.is_bot,
				.from.first_name,
				.from.last_name,
				.from.username,
				.chat.id,
				(if .chat.type == "private" then .chat.username else .chat.title end),
				.chat.type,
				.date,
				(select(.text) | .text), (select(.caption) | .caption),
				(if .reply_to_message then
					.reply_to_message | (
						"true",
						.message_id,
						.from.id,
						.from.is_bot,
						.from.first_name,
						.from.last_name,
						.from.username,
						.date,
						.text
					)
				else
					"false"
				end)]
				| @sh' <<< "${_events[$i]}"

			event[message_id]="${_tmp[0]}"
			event[from_id]="${_tmp[1]}"
			event[from_is_bot]="${_tmp[2]}"
			event[from_first_name]="$(_unescape_text "${_tmp[3]}")"
			event[from_last_name]="$(_unescape_text "${_tmp[4]}")"
			event[from_username]="${_tmp[5]}"
			event[chat_id]="${_tmp[6]}"
			event[chat_title]="$(_unescape_text "${_tmp[7]}")"
			event[chat_type]="${_tmp[8]}"
			event[date]="${_tmp[9]}"
			event[text]="$(_unescape_text "${_tmp[10]}")"

			if [[ "${_tmp[11]}" == "true" ]]; then
				event[reply]=true
				event[reply_message_id]="${_tmp[12]}"
				event[reply_from_id]="${_tmp[13]}"
				event[reply_from_is_bot]="${_tmp[14]}"
				event[reply_from_first_name]="$(_unescape_text "${_tmp[15]}")"
				event[reply_from_last_name]="$(_unescape_text "${_tmp[16]}")"
				event[reply_from_username]="${_tmp[17]}"
				event[reply_date]="${_tmp[18]}"
				event[reply_text]="$(_unescape_text "${_tmp[19]}")"
			else
				event[reply]=false
			fi

			unset _tmp

			if [[ "$_msg_type" == forwarded_message ]]; then
				_jq_to_array '.message |
				[.forward_from.id,
				.forward_from.is_bot,
				.forward_from.first_name,
				.forward_from.last_name,
				.forward_from.username,
				.forward_date] | @sh' <<< "${_events[$i]}"

				event[forward_id]="${_tmp[0]}"
				event[forward_is_bot]="${_tmp[1]}"
				event[forward_first_name]="$(_unescape_text "${_tmp[2]}")"
				event[forward_last_name]="$(_unescape_text "${_tmp[3]}")"
				event[forward_username]="${_tmp[4]}"
				event[forward_date]="${_tmp[5]}"
				unset _tmp
			fi

			event[type]="$_msg_type"
			event[json]="${_events[$i]}"
			if [[ "$_msg_type" == edited_message ]]; then
				_on_edit
			elif [[ "$_event_type" == animation ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .animation |
					[.file_name,
					.mime_type,
					.duration,
					.width,
					.height,
					.thumb.file_id,
					.thumb.file_unique_id,
					.thumb.height,
					.thumb.width,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"
				event[animation_file_name]="${_tmp[0]}"
				event[animation_mime_type]="${_tmp[1]}"
				event[animation_duration]="${_tmp[2]}"
				event[animation_width]="${_tmp[3]}"
				event[animation_height]="${_tmp[4]}"
				event[animation_thumb_file_id]="${_tmp[5]}"
				event[animation_thumb_file_unique_id]="${_tmp[6]}"
				event[animation_thumb_height]="${_tmp[7]}"
				event[animation_thumb_width]="${_tmp[8]}"
				event[animation_file_id]="${_tmp[9]}"
				event[animation_file_unique_id]="${_tmp[10]}"
				event[animation_file_size]="${_tmp[11]}"
				unset _tmp
				
				_on_animation
			elif [[ "$_event_type" == audio ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .audio |
					[.duration,
					.file_name,
					.mime_type,
					.title,
					.performer,
					.thumb.file_id,
					.thumb.file_unique_id,
					.thumb.width,
					.thumb.height,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"
				event[audio_duration]="${_tmp[0]}"
				event[file_name]="${_tmp[1]}"
				event[mime_type]="${_tmp[2]}"
				event[title]="$(_unescape_text "${_tmp[3]}")"
				event[performer]="$(_unescape_text "${_tmp[4]}")"
				event[thumb_file_id]="${_tmp[5]}"
				event[thumb_file_unique_id]="${_tmp[6]}"
				event[thumb_width]="${_tmp[7]}"
				event[thumb_height]="${_tmp[8]}"
				event[file_id]="${_tmp[9]}"
				event[file_unique_id]="${_tmp[10]}"
				event[file_size]="${_tmp[11]}"
				unset _tmp
				
				_on_audio
			elif [[ "$_event_type" == document ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .document |
					[.file_name,
					.mime_type,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"

				event[document_file_name]="${_tmp[0]}"
				event[document_mime_type]="${_tmp[1]}"
				event[document_file_id]="${_tmp[2]}"
				event[document_file_unique_id]="${_tmp[3]}"
				event[document_file_size]="${_tmp[4]}"
				unset _tmp

				_on_document
			elif [[ "$_event_type" == photo ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .photo[-1] |
					[.file_id,
					.file_unique_id,
					.file_size,
					.width,
					.height] | @sh' <<< "${_events[$i]}" # stub - add more things to me!
				event[photo_file_id]="${_tmp[0]}"
				event[photo_file_unique_id]="${_tmp[1]}"
				event[photo_file_size]="${_tmp[2]}"
				event[photo_height]="${_tmp[3]}"
				event[photo_width]="${_tmp[4]}"
				unset _tmp

				_on_photo
			elif [[ "$_event_type" == sticker ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .sticker |
					[.width,
					.height,
					.emoji,
					.set_name,
					.is_animated,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"
				event[sticker_width]="${_tmp[0]}"
				event[sticker_height]="${_tmp[1]}"
				event[sticker_emoji]="${_tmp[2]}"
				event[sticker_set_name]="${_tmp[3]}"
				event[sticker_is_animated]="${_tmp[4]}"
				event[sticker_file_id]="${_tmp[5]}"
				event[sticker_file_unique_id]="${_tmp[6]}"
				event[sticker_file_size]="${_tmp[7]}"
				unset _tmp
				
				_on_sticker
			elif [[ "$_event_type" == video ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .video |
					[.duration,
					.width,
					.height,
					.file_name,
					.mime_type,
					.thumb.file_id,
					.thumb.file_unique_id,
					.thumb.width,
					.thumb.height,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"
				event[video_duration]="${_tmp[0]}"
				event[video_width]="${_tmp[1]}"
				event[video_height]="${_tmp[2]}"
				event[video_file_name]="${_tmp[3]}"
				event[video_mime_type]="${_tmp[4]}"
				event[video_thumb_file_id]="${_tmp[5]}"
				event[video_thumb_file_unique_id]="${_tmp[6]}"
				event[video_thumb_width]="${_tmp[7]}"
				event[video_thumb_height]="${_tmp[8]}"
				event[video_file_id]="${_tmp[9]}"
				event[video_file_unique_id]="${_tmp[10]}"
				event[video_file_size]="${_tmp[11]}"
				unset _tmp

				_on_video
			elif [[ "$_event_type" == video_note ]]; then
				# implement it yourself or use raw JSON
			 	# I don't consider video_note to be a valid way of messaging
				_on_video_note 
			elif [[ "$_event_type" == voice ]]; then
				_jq_to_array '(select(.message) | .message), (select(.edited_message) | .edited_message) | .voice |
					[.duration,
					.mime_type,
					.file_id,
					.file_unique_id,
					.file_size] | @sh' <<< "${_events[$i]}"
				event[voice_duration]="${_tmp[0]}"
				event[voice_mime_type]="${_tmp[1]}"
				event[voice_file_id]="${_tmp[2]}"
				event[voice_file_unique_id]="${_tmp[3]}"
				event[voice_file_size]="${_tmp[4]}"
				unset _tmp
				
				_on_voice
			else
				_on_msg
			fi
			declare -p event
			unset event
		done
		[[ ${#_events[@]} -gt 0 ]] && _update_id=$(jq 'select(.update_id != null) | .update_id' <<< "${_events[-1]}")
		[[ $_update_id != '' ]] && _offset=$((_update_id+1))
	done
}