#!/bin/bash
# notify - display a macOS notification, speak it, or do both
#
# Usage:
#   notify [options] [message ...]
#   command | notify [options]
#
# Options:
#   -p, --say                  Display the notification and speak the message
#   -P, --say-only             Speak without displaying a notification
#       --notify-only          Disable speech, including NOTIFY_SAY
#   -t, --title title          Notification title (default: "Notification")
#   -s, --subtitle subtitle    Notification subtitle
#   -S, --sound sound          Notification sound (default: "Glass")
#   -n, --no-sound             Suppress the notification sound
#   -l, --list-sounds          List notification sounds and exit
#   -v, --voice voice          macOS speech voice
#   -r, --rate wpm             Speech rate in words per minute
#       --say-text text        Speak text instead of the displayed message
#   -b, --background           Start speech asynchronously
#   -L, --list-voices          List installed voices and exit
#   -h, --help                 Show help message
#
# Environment:
#   NOTIFY_TITLE       Default title
#   NOTIFY_SOUND       Default notification sound
#   NOTIFY_SAY         Set to 1, true, yes, or on to enable --say
#   NOTIFY_VOICE       Default speech voice
#   NOTIFY_RATE        Default speech rate

_notify() (
    local SCRIPT_NAME
    SCRIPT_NAME="$(basename "${BASH_SOURCE[0]}")"
    case "${BASH_SOURCE[0]}" in /dev/*|/proc/*) SCRIPT_NAME="" ;; esac
    case "$SCRIPT_NAME" in ""|bash|sh|zsh|dash) SCRIPT_NAME="notify" ;; esac

    # The subshell keeps these settings from changing a shell that sources us
    set +f
    shopt -u failglob

    _error() { echo "[ERR][$SCRIPT_NAME] $*" >&2; }

    _show_help() {
        local s=""
        local r=""
        [ -t 1 ] && s=$'\033[4m'
        [ -t 1 ] && r=$'\033[24m'

        cat <<EOF
NAME
  $SCRIPT_NAME - display a macOS notification, speak it, or do both

SYNOPSIS
  $SCRIPT_NAME [${s}options${r}] [${s}message${r} ...]
  ${s}command${r} | $SCRIPT_NAME [${s}options${r}]

DESCRIPTION
  Displays a macOS notification by default. --say adds synthesized speech;
  --say-only speaks without displaying a notification. The message may be
  passed as positional arguments or piped to stdin.

  Notification Center attributes notifications to Script Editor, the
  osascript host application. Notification duration is controlled by macOS
  under System Settings > Notifications > Script Editor.

OUTPUT MODES
  -p, --say                  Display the notification and speak the message
  -P, --say-only             Speak the message without displaying it
      --notify-only          Disable speech, including NOTIFY_SAY

  The last explicit output-mode option wins. Without one, using a speech
  option implies --say. Otherwise, notification-only output is the default.

NOTIFICATION OPTIONS
  -t, --title ${s}title${r}          Title (default: "Notification")
  -s, --subtitle ${s}subtitle${r}    Subtitle
  -S, --sound ${s}sound${r}          Sound name (default: "Glass")
  -n, --no-sound             Suppress the notification sound
  -l, --list-sounds          List available notification sounds and exit

SPEECH OPTIONS
  -v, --voice ${s}voice${r}          Voice name (default: macOS system voice)
  -r, --rate ${s}wpm${r}             Speaking rate in words per minute
      --say-text ${s}text${r}        Speak ${s}text${r} instead of the displayed message
  -b, --background           Start say asynchronously
  -L, --list-voices          List installed voices and their locales, then exit

INFORMATION
  -h, --help                 Show this help message

ENVIRONMENT
  NOTIFY_TITLE       Default title
  NOTIFY_SOUND       Default notification sound
  NOTIFY_SAY         Set to 1, true, yes, or on to enable --say
  NOTIFY_VOICE       Default voice when speech is enabled
  NOTIFY_RATE        Default speaking rate when speech is enabled

EXAMPLES
  $SCRIPT_NAME "Backup complete"
  make && $SCRIPT_NAME -t "Build" --say --no-sound "Build finished"
  $SCRIPT_NAME --say-only -v Samantha -r 190 "Tea is ready"
  $SCRIPT_NAME --say --say-text "Deploy healthy" "Production deployment is healthy"
  $SCRIPT_NAME --list-voices

EXIT STATUS
  0  Success
  1  No notification sounds were found
  2  Invalid arguments or missing required message
  3  A required macOS tool (osascript or say) is unavailable

  Otherwise, the status of a failed osascript or foreground say process is
  returned. Background mode can report only whether say was started.

DEPENDENCIES
  osascript  Notification output (macOS only)
  say        Speech output and voice discovery (macOS only)
EOF
    }

    _list_sounds() {
        local sounds=""
        local user_sounds=""
        local dir
        local file
        local name

        if [ -n "${HOME:-}" ]; then user_sounds="$HOME/Library/Sounds"; fi
        for dir in /System/Library/Sounds /Library/Sounds "$user_sounds"; do
            [ -n "$dir" ] || continue
            [ -d "$dir" ] || continue
            for file in "$dir"/*; do
                [ -f "$file" ] || continue
                name="${file##*/}"
                name="${name%.*}"
                sounds="${sounds:+$sounds$'\n'}$name"
            done
        done

        if [ -z "$sounds" ]; then
            _error "No sounds found in the system, local, or user Sounds directories"
            return 1
        fi

        printf '%s\n' "$sounds" | sort -u
    }

    _expand_short_opts() {
        # $1 = string of short-opt letters that take a value (e.g. "nXHd"); "" for flag-only scripts
        # $2..$N = "$@"
        # Populates _EXPANDED; caller does: set -- "${_EXPANDED[@]}"; unset _EXPANDED
        local value_opts="$1"; shift
        _EXPANDED=()
        local passthru=""
        local arg
        local rest
        local c
        for arg in "$@"; do
            if [ -n "$passthru" ]; then _EXPANDED+=("$arg"); continue; fi
            case "$arg" in
                --)       passthru=1; _EXPANDED+=("$arg") ;;
                --*|-|"") _EXPANDED+=("$arg") ;;
                -[a-zA-Z]?*)
                    rest="${arg#-}"
                    while [ -n "$rest" ]; do
                        c="${rest%"${rest#?}"}"; rest="${rest#?}"
                        _EXPANDED+=("-$c")
                        case "$value_opts" in *"$c"*)
                            [ -n "$rest" ] && _EXPANDED+=("$rest")
                            rest="" ;;
                        esac
                    done ;;
                *)        _EXPANDED+=("$arg") ;;
            esac
        done
    }

    _env_true() {
        case "${1:-}" in
            1|[Tt][Rr][Uu][Ee]|[Yy][Ee][Ss]|[Oo][Nn]) return 0 ;;
            *) return 1 ;;
        esac
    }

    _set_action() {
        local requested="$1"
        if [ -n "$action" ]; then
            _error "Only one list option may be used at a time"
            return 2
        fi
        action="$requested"
    }

    _is_positive_integer() {
        case "$1" in
            ""|*[!0-9]*) return 1 ;;
            *[1-9]*) return 0 ;;
            *) return 1 ;;
        esac
    }

    local title="${NOTIFY_TITLE:-Notification}"
    local subtitle=""
    local sound="${NOTIFY_SOUND:-Glass}"
    local no_sound=""
    local explicit_mode=""
    local speech_requested=""
    local action=""
    local voice="${NOTIFY_VOICE:-}"
    local rate="${NOTIFY_RATE:-}"
    local say_text=""
    local say_text_set=""
    local background=""
    local -a args=()
    local -a _EXPANDED=()

    _expand_short_opts "tsSvr" "$@"
    set -- "${_EXPANDED[@]}"; unset _EXPANDED

    while [ $# -gt 0 ]; do
        case "$1" in
            -h|--help)
                _show_help
                return 0
                ;;
            -p|--say)
                explicit_mode="both"
                shift
                ;;
            -P|--say-only)
                explicit_mode="say"
                shift
                ;;
            # Negation flag: --notify-only intentionally has no short form
            --notify-only)
                explicit_mode="notify"
                shift
                ;;
            -l|--list-sounds)
                _set_action "sounds" || return 2
                shift
                ;;
            -L|--list-voices)
                _set_action "voices" || return 2
                shift
                ;;
            -n|--no-sound)
                no_sound=1
                shift
                ;;
            -t|--title)
                [ -n "${2-}" ] || { _error "-t|--title requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                title="$2"
                shift 2
                ;;
            --title=*)
                title="${1#*=}"
                [ -n "$title" ] || { _error "-t|--title requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            -s|--subtitle)
                [ -n "${2-}" ] || { _error "-s|--subtitle requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                subtitle="$2"
                shift 2
                ;;
            --subtitle=*)
                subtitle="${1#*=}"
                [ -n "$subtitle" ] || { _error "-s|--subtitle requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            -S|--sound)
                [ -n "${2-}" ] || { _error "-S|--sound requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                sound="$2"
                shift 2
                ;;
            --sound=*)
                sound="${1#*=}"
                [ -n "$sound" ] || { _error "-S|--sound requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                shift
                ;;
            -v|--voice)
                [ -n "${2-}" ] || { _error "-v|--voice requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                voice="$2"
                speech_requested=1
                shift 2
                ;;
            --voice=*)
                voice="${1#*=}"
                [ -n "$voice" ] || { _error "-v|--voice requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                speech_requested=1
                shift
                ;;
            -r|--rate)
                [ -n "${2-}" ] || { _error "-r|--rate requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                rate="$2"
                speech_requested=1
                shift 2
                ;;
            --rate=*)
                rate="${1#*=}"
                [ -n "$rate" ] || { _error "-r|--rate requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                speech_requested=1
                shift
                ;;
            # Collision: --say-text stays long-only because -s and -t are notification options
            --say-text)
                [ -n "${2-}" ] || { _error "--say-text requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                say_text="$2"
                say_text_set=1
                speech_requested=1
                shift 2
                ;;
            --say-text=*)
                say_text="${1#*=}"
                [ -n "$say_text" ] || { _error "--say-text requires a value. Run \`$SCRIPT_NAME -h\` for usage"; return 2; }
                say_text_set=1
                speech_requested=1
                shift
                ;;
            -b|--background)
                background=1
                speech_requested=1
                shift
                ;;
            --)
                shift
                while [ $# -gt 0 ]; do
                    args+=("$1")
                    shift
                done
                ;;
            -*)
                _error "Unknown argument '$1'. Run \`$SCRIPT_NAME -h\` for usage"
                return 2
                ;;
            *)
                args+=("$1")
                shift
                ;;
        esac
    done

    if [ -n "$action" ]; then
        if [ "${#args[@]}" -gt 0 ]; then
            _error "List options do not accept a message"
            return 2
        fi

        case "$action" in
            sounds)
                _list_sounds
                return $?
                ;;
            voices)
                if ! command -v say >/dev/null 2>&1; then
                    _error "say is required"
                    return 3
                fi
                say -v '?'
                return $?
                ;;
        esac
    fi

    local message=""
    local index
    if [ "${#args[@]}" -gt 0 ]; then
        message="${args[0]}"
        index=1
        while [ "$index" -lt "${#args[@]}" ]; do
            message="$message ${args[$index]}"
            index=$((index + 1))
        done
    elif [ -p /dev/stdin ] || [ ! -t 0 ]; then
        message="$(cat)"
    fi

    if [ -z "$message" ]; then
        _error "MESSAGE is required (pass as arguments or pipe stdin)"
        _show_help >&2
        return 2
    fi

    local mode="notify"
    if [ -n "$explicit_mode" ]; then
        mode="$explicit_mode"
    elif _env_true "${NOTIFY_SAY:-}" || [ -n "$speech_requested" ]; then
        mode="both"
    fi

    if [ "$mode" = "notify" ] && [ -n "$explicit_mode" ] && [ -n "$speech_requested" ]; then
        _error "Speech options cannot be combined with --notify-only"
        return 2
    fi

    local notify_enabled=""
    local say_enabled=""
    case "$mode" in
        notify) notify_enabled=1 ;;
        say) say_enabled=1 ;;
        both) notify_enabled=1; say_enabled=1 ;;
    esac

    if [ -n "$say_enabled" ] && [ -n "$rate" ] && ! _is_positive_integer "$rate"; then
        _error "-r|--rate must be a positive integer in words per minute"
        return 2
    fi

    if [ -n "$notify_enabled" ] && ! command -v osascript >/dev/null 2>&1; then
        _error "osascript is required"
        return 3
    fi
    if [ -n "$say_enabled" ] && ! command -v say >/dev/null 2>&1; then
        _error "say is required"
        return 3
    fi

    local effective_sound="$sound"
    if [ -n "$no_sound" ]; then effective_sound=""; fi

    local speech_text="$message"
    local -a say_args=()
    if [ -n "$say_enabled" ]; then
        if [ -n "$say_text_set" ]; then speech_text="$say_text"; fi
        [ -n "$voice" ] && say_args+=(-v "$voice")
        [ -n "$rate" ] && say_args+=(-r "$rate")
    fi

    local notify_rc=0
    local say_rc=0

    if [ -n "$notify_enabled" ]; then
        osascript - "$message" "$title" "$subtitle" "$effective_sound" <<'APPLESCRIPT'
on run argv
    set msg to item 1 of argv
    set ttl to item 2 of argv
    set sub to item 3 of argv
    set snd to item 4 of argv
    if sub is "" and snd is "" then
        display notification msg with title ttl
    else if sub is "" then
        display notification msg with title ttl sound name snd
    else if snd is "" then
        display notification msg with title ttl subtitle sub
    else
        display notification msg with title ttl subtitle sub sound name snd
    end if
end run
APPLESCRIPT
        notify_rc=$?
    fi

    if [ -n "$say_enabled" ]; then
        if [ -n "$background" ]; then
            say "${say_args[@]}" <<< "$speech_text" &
            say_rc=$?
        else
            say "${say_args[@]}" <<< "$speech_text"
            say_rc=$?
        fi
    fi

    if [ "$notify_rc" -ne 0 ]; then return "$notify_rc"; fi
    return "$say_rc"
)

_notify "$@"
__notify_rc=$?
unset -f _notify
if [ -n "${BASH_SOURCE[0]}" ] && [ "${BASH_SOURCE[0]}" != "$0" ]; then
    eval "unset __notify_rc; return $__notify_rc"
fi
eval "unset __notify_rc; exit $__notify_rc"