notify-send.sh

#!/usr/bin/env bash

# notify-send.sh - drop-in replacement for notify-send with more features
# Copyright (C) 2015-2021 notify-send.sh authors (see AUTHORS file)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Desktop Notifications Specification
# https://developer.gnome.org/notification-spec/

VERSION=1.2
NOTIFY_ARGS=(--session
             --dest org.freedesktop.Notifications
             --object-path /org/freedesktop/Notifications)
EXPIRE_TIME=-1
APP_NAME="${0##*/}"
REPLACE_ID=0
URGENCY=1
HINTS=()
SUMMARY_SET=n

help() {
    cat <<EOF
Usage:
  notify-send.sh [OPTION...] <SUMMARY> [BODY] - create a notification

Help Options:
  -?|--help                         Show help options

Application Options:
  -u, --urgency=LEVEL               Specifies the urgency level (low, normal, critical).
  -t, --expire-time=TIME            Specifies the timeout in milliseconds at which to expire the notification.
  -f, --force-expire                Forcefully closes the notification when the notification has expired.
  -a, --app-name=APP_NAME           Specifies the app name for the icon.
  -i, --icon=ICON[,ICON...]         Specifies an icon filename or stock icon to display.
  -c, --category=TYPE[,TYPE...]     Specifies the notification category.
  -h, --hint=TYPE:NAME:VALUE        Specifies basic extra data to pass. Valid types are int, double, string and byte.
  -o, --action=LABEL:COMMAND        Specifies an action. Can be passed multiple times. LABEL is usually a button's label. COMMAND is a shell command executed when action is invoked.
  -d, --default-action=COMMAND      Specifies the default action which is usually invoked by clicking the notification.
  -l, --close-action=COMMAND        Specifies the action invoked when notification is closed.
  -p, --print-id                    Print the notification ID to the standard output.
  -r, --replace=ID                  Replace existing notification.
  -R, --replace-file=FILE           Store and load notification replace ID to/from this file.
  -s, --close=ID                    Close notification.
  -v, --version                     Version of the package.

EOF
}

convert_type() {
    case "$1" in
        int) echo int32 ;;
        double|string|byte) echo "$1" ;;
        *) echo error; return 1 ;;
    esac
}

make_action_key() {
    echo "$(tr -dc _A-Z-a-z-0-9 <<< \"$1\")${RANDOM}"
}

make_action() {
    local action_key="$1"
    printf -v text "%q" "$2"
    echo "\"$action_key\", \"$text\""
}

make_hint() {
    type=$(convert_type "$1")
    [[ ! $? = 0 ]] && return 1
    name="$2"
    [[ "$type" = string ]] && command="\"$3\"" || command="$3"
    echo "\"$name\": <$type $command>"
}

concat_actions() {
    local result="$1"
    shift
    for s in "$@"; do
        result="$result, $s"
    done
    echo "[$result]"
}

concat_hints() {
    local result="$1"
    shift
    for s in "$@"; do
        result="$result, $s"
    done
    echo "{$result}"
}

parse_notification_id(){
    sed 's/(uint32 \([0-9]\+\),)/\1/g'
}

notify() {
    local actions="$(concat_actions "${ACTIONS[@]}")"
    local hints="$(concat_hints "${HINTS[@]}")"

    NOTIFICATION_ID=$(gdbus call "${NOTIFY_ARGS[@]}"  \
                            --method org.freedesktop.Notifications.Notify \
                            -- \
                            "$APP_NAME" "$REPLACE_ID" "$ICON" "$SUMMARY" "$BODY" \
                            "${actions}" "${hints}" "int32 $EXPIRE_TIME" \
                          | parse_notification_id)

    if [[ -n "$STORE_ID" ]] ; then
        echo "$NOTIFICATION_ID" > "$STORE_ID"
    fi
    if [[ -n "$PRINT_ID" ]] ; then
        echo "$NOTIFICATION_ID"
    fi

    if [[ -n "$FORCE_EXPIRE" ]] ; then
        SLEEP_TIME="$( LC_NUMERIC=C printf %f "${EXPIRE_TIME}e-3" )"
        ( sleep "$SLEEP_TIME" ; notify_close "$NOTIFICATION_ID" ) &
    fi

    maybe_run_action_handler
}

notify_close () {
    gdbus call "${NOTIFY_ARGS[@]}"  --method org.freedesktop.Notifications.CloseNotification "$1" >/dev/null
}

process_urgency() {
    case "$1" in
        low) URGENCY=0 ;;
        normal) URGENCY=1 ;;
        critical) URGENCY=2 ;;
        *) echo "Unknown urgency $URGENCY specified. Known urgency levels: low, normal, critical."
           exit 1
           ;;
    esac
}

process_category() {
    IFS=, read -a categories <<< "$1"
    for category in "${categories[@]}"; do
        hint="$(make_hint string category "$category")"
        HINTS=("${HINTS[@]}" "$hint")
    done
}

process_hint() {
    IFS=: read type name command <<< "$1"
    if [[ -z "$name" ]] || [[ -z "$command" ]] ; then
        echo "Invalid hint syntax specified. Use TYPE:NAME:VALUE."
        exit 1
    fi
    hint="$(make_hint "$type" "$name" "$command")"
    if [[ ! $? = 0 ]] ; then
        echo "Invalid hint type \"$type\". Valid types are int, double, string and byte."
        exit 1
    fi
    HINTS=("${HINTS[@]}" "$hint")
}

maybe_run_action_handler() {
    if [[ -n "$NOTIFICATION_ID" ]] && [[ -n "$ACTION_COMMANDS" ]]; then
        local notify_action="$(dirname ${BASH_SOURCE[0]})/notify-action.sh"
        if [[ -x "$notify_action" ]] ; then
            "$notify_action" "$NOTIFICATION_ID" "${ACTION_COMMANDS[@]}" &
            exit 0
        else
            echo "executable file not found: $notify_action"
            exit 1
        fi
    fi
}

process_action() {
    IFS=: read name command <<<"$1"
    if [[ -z "$name" ]] || [[ -z "$command" ]]; then
        echo "Invalid action syntax specified. Use NAME:COMMAND."
        exit 1
    fi

    local action_key="$(make_action_key "$name")"
    ACTION_COMMANDS=("${ACTION_COMMANDS[@]}" "$action_key" "$command")

    local action="$(make_action "$action_key" "$name")"
    ACTIONS=("${ACTIONS[@]}" "$action")
}

process_special_action() {
    action_key="$1"
    command="$2"

    if [[ -z "$action_key" ]] || [[ -z "$command" ]]; then
        echo "Command must not be empty"
        exit 1
    fi

    ACTION_COMMANDS=("${ACTION_COMMANDS[@]}" "$action_key" "$command")

    if [[ "$action_key" != close ]]; then
        local action="$(make_action "$action_key" "$name")"
        ACTIONS=("${ACTIONS[@]}" "$action")
    fi
}

process_posargs() {
    if [[ "$1" = -* ]] && ! [[ "$positional" = yes ]] ; then
        echo "Unknown option $1"
        exit 1
    else
        if [[ "$SUMMARY_SET" = n ]]; then
            SUMMARY="$1"
            SUMMARY_SET=y
        else
            BODY="$1"
        fi
    fi
}

while (( $# > 0 )) ; do
    case "$1" in
        -\?|--help)
            help
            exit 0
            ;;
        -v|--version)
            echo "${0##*/} $VERSION"
            exit 0
            ;;
        -u|--urgency|--urgency=*)
            [[ "$1" = --urgency=* ]] && urgency="${1#*=}" || { shift; urgency="$1"; }
            process_urgency "$urgency"
            ;;
        -t|--expire-time|--expire-time=*)
            [[ "$1" = --expire-time=* ]] && EXPIRE_TIME="${1#*=}" || { shift; EXPIRE_TIME="$1"; }
            if ! [[ "$EXPIRE_TIME" =~ ^-?[0-9]+$ ]]; then
                echo "Invalid expire time: ${EXPIRE_TIME}"
                exit 1;
            fi
            ;;
        -f|--force-expire)
            FORCE_EXPIRE=yes
            ;;
        -a|--app-name|--app-name=*)
            [[ "$1" = --app-name=* ]] && APP_NAME="${1#*=}" || { shift; APP_NAME="$1"; }
            ;;
        -i|--icon|--icon=*)
            [[ "$1" = --icon=* ]] && ICON="${1#*=}" || { shift; ICON="$1"; }
            ;;
        -c|--category|--category=*)
            [[ "$1" = --category=* ]] && category="${1#*=}" || { shift; category="$1"; }
            process_category "$category"
            ;;
        -h|--hint|--hint=*)
            [[ "$1" = --hint=* ]] && hint="${1#*=}" || { shift; hint="$1"; }
            process_hint "$hint"
            ;;
        -o | --action | --action=*)
            [[ "$1" == --action=* ]] && action="${1#*=}" || { shift; action="$1"; }
            process_action "$action"
            ;;
        -d | --default-action | --default-action=*)
            [[ "$1" == --default-action=* ]] && default_action="${1#*=}" || { shift; default_action="$1"; }
            process_special_action default "$default_action"
            ;;
        -l | --close-action | --close-action=*)
            [[ "$1" == --close-action=* ]] && close_action="${1#*=}" || { shift; close_action="$1"; }
            process_special_action close "$close_action"
            ;;
        -p|--print-id)
            PRINT_ID=yes
            ;;
        -r|--replace|--replace=*)
            [[ "$1" = --replace=* ]] && REPLACE_ID="${1#*=}" || { shift; REPLACE_ID="$1"; }
            ;;
        -R|--replace-file|--replace-file=*)
            [[ "$1" = --replace-file=* ]] && filename="${1#*=}" || { shift; filename="$1"; }
            if [[ -s "$filename" ]]; then
                REPLACE_ID="$(< "$filename")"
            fi
            STORE_ID="$filename"
            ;;
        -s|--close|--close=*)
            [[ "$1" = --close=* ]] && close_id="${1#*=}" || { shift; close_id="$1"; }
            # always check that --close provides a numeric value
            if [[ -z "$close_id" || ! "$close_id" =~ ^[0-9]+$ ]]; then
              echo "Invalid close id: '$close_id'"
              exit 1
            fi
            notify_close "$close_id"
            exit $?
            ;;
        --)
            positional=yes
            ;;
        *)
            process_posargs "$1"
            ;;
    esac
    shift
done

# always force --replace and --replace-file to provide a numeric value; 0 means no id provided
if [[ -z "$REPLACE_ID" || ! "$REPLACE_ID" =~ ^[0-9]+$ ]]; then
    REPLACE_ID=0
fi

# urgency is always set
HINTS=("$(make_hint byte urgency "$URGENCY")" "${HINTS[@]}")

if [[ "$SUMMARY_SET" = n ]] ; then
    help
    exit 1
else
    notify
fi