signal-cli-to-inbox

#! /bin/sh
# Repo: https://github.com/jneidel/signal-cli-to-file

# In signal-cli registered number you want to receive messages for
SIGNAL_NUMBER=
# for example:
SIGNAL_NUMBER=+4917222222222

# The directory where messages are to be created as files
INBOX_DIR=
# for example:
INBOX_DIR=$HOME/org/0_inbox

# Default message file extension
MESSAGE_FILE_EXT=md

# Turn off to not keep backups of the parsed messages in $BACKUP_DIR
BACKUP_MESSAGES=1

# Turn on to filter incoming message to only allow those on the whitelist
USE_WHITELIST=0
WHITELIST= # one number per line

if [ "$1" = "--help" ] || [ "$1" = "-h" ] || [ "$1" = "help" ]; then
  cat <<EOF
$ signal-to-inbox
Receive signal messages and sort them into the inbox

Prerequisite is to register the number with signal
EOF
  exit
fi
if [ -z "$SIGNAL_NUMBER" ] || [ -z "$INBOX_DIR" ]; then
  echo "Required variables are not configured"
  exit 1
fi

command -v signal-cli >/dev/null || { echo "signal-cli is not installed" 1>&2; exit 127; }

BACKUP_DIR="${XDG_DATA_HOME:-$HOME/.cache}/signal-cli"
ATTACHMENTS_DIR="$BACKUP_DIR/attachments"
mkdir -p "$BACKUP_DIR"
CACHE_FILE="$BACKUP_DIR/received-messages-$(date +%s)"

is_whitelisted() {
  [ "$USE_WHITELIST" -eq 0 ] && true

  local number_to_test="$1"
  if grep "$number_to_test" $WHITELIST >/dev/null; then
    true
  else
    false
  fi
}

receive() {
  ERROR_FILE="$INBOX_DIR/signal-cli-errors-$(date +%s)"
  signal-cli -a $SIGNAL_NUMBER receive --ignore-stories --send-read-receipts >$CACHE_FILE 2>/tmp/signal-cli-errors || {
    echo "Receiving signal messages failed!\nCACHE_FILE=$CACHE_FILE\n\n" >"$ERROR_FILE"
    cat /tmp/signal-cli-errors "$CACHE_FILE" >>"$ERROR_FILE"
  }
}

parseMessages() {
  if [ -z "$(cat $CACHE_FILE)" ]; then
    rm $CACHE_FILE
  else
    N=0
    BODY=""
    ATTACHMENT=""
    ignore_message=0
    attachment_count=1
    is_multiline=0
    multiline_body_done=0
    while read line; do
      if [ -n "$BODY" ] && [ "$multiline_body_done" -eq 0 ]; then
        if echo $line | grep -ve "^Expires in:" >/dev/null; then
          BODY="${BODY}\n$line"
          is_multiline=1
        else
          multiline_body_done=1
        fi
      fi

      has_envelope=`echo $line | grep -Po "^Envelope from: .+?\K\+\d+"`
      if [ -n "$has_envelope" ] && ! is_whitelisted "$has_envelope"; then
        ignore_message=1
      fi

      has_body=`echo $line | grep -Po "^Body: \K.+"`
      if [ -n "$has_body" ]; then
        BODY="$has_body"
      fi

      has_filename=`echo $line | grep -Po "Filename: \K.+"`
      if [ -n "$ATTACHMENT" ] && [ -n "$has_filename" ] && [ "$ignore_message" -eq 0 ]; then
          cp "$ATTACHMENT_DIR/$ATTACHMENT" "$INBOX_DIR/$has_filename"
          ATTACHMENT=""
          attachment_count=$((${attachment_count}+1))
      fi

      has_attachement=`echo $line | grep -Po "Id: \K.+"`
      if [ -n "$has_attachement" ] && [ "$ignore_message" -eq 0 ]; then
        if [ -n "$ATTACHMENT" ]; then
          if [ -n "$BODY" ]; then
            cp "$ATTACHMENT_DIR/$ATTACHMENT" "$INBOX_DIR/$BODY-$attachment_count.${ATTACHMENT##*.}"
          else
            cp "$ATTACHMENT_DIR/$ATTACHMENT" $INBOX_DIR/
          fi
          ATTACHMENT=""
        fi
        ATTACHMENT="$has_attachement"
      fi

      if [ -z "$line" ] && ([ "$is_multiline" -eq 0 ] || [ "$multiline_body_done" -eq 1 ]); then # reset
        if [ -n "$BODY" ] && [ -z "$ATTACHMENT" ] && [ "$ignore_message" -eq 0 ]; then
          body_shortend=`echo $BODY | tr "\n" " " | cut -c-50`
          filename=$body_shortend
          if echo $body_shortend | grep ":" >/dev/null; then
            filename=`echo $body_shortend | cut -d: -f1`
          fi

          # write text contents to file
          echo "$BODY" | grep -v "This transcript was generated generated by" >>"$INBOX_DIR/${filename}.$MESSAGE_FILE_EXT"
        fi

        if [ -n "$ATTACHMENT" ] && [ "$ignore_message" -eq 0 ]; then
          if [ -n "$BODY" ]; then
            cp "$ATTACHMENT_DIR/$ATTACHMENT" "$INBOX_DIR/$BODY-$attachment_count.${ATTACHMENT##*.}"
          else
            cp "$ATTACHMENT_DIR/$ATTACHMENT" $INBOX_DIR/
          fi
        fi

        N=$((${N}+1))
        BODY=""
        ATTACHMENT=""
        attachment_count=1
        multiline_body_done=0
        is_multiline=0
        ignore_message=0
      fi
    done <$CACHE_FILE
  fi
}

# To a send desktop notification
# ~/scripts/cron/cron-notify-send "Receiving notes from signal"
# see: https://github.com/jneidel/dotfiles/blob/master/scripts/cron/cron-notify-send

receive
parseMessages

[ "$BACKUP_MESSAGES" -eq 0 ] && rm "$CACHE_FILE"